Duke Energy (DUK) 10-K 25 Feb 21 2020 FY Annual report Financial data

Cover Page

Cover Page - USD ($)	12 Months Ended
	Dec. 31, 2020	Jan. 31, 2021	Jun. 30, 2020
Document Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	1-32853
Entity Registrant Name	DUKE ENERGY CORPORATION
Entity Tax Identification Number	20-2777218
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	550 South Tryon Street
Entity Address, City or Town	Charlotte
Entity Address, State or Province	NC
Entity Address, Postal Zip Code	28202-1803
City Area Code	704
Local Phone Number	382-3853
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 58,688,204,289
Entity Common Stock, Shares Outstanding		768,663,580
Documents Incorporated by Reference	Portions of the Duke Energy definitive proxy statement for the 2021 Annual Meeting of the Shareholders or an amendment to this Annual Report are incorporated by reference into PART III, Items 10, 11 and 13 hereof. This combined Form 10-K is filed separately by eight registrants: Duke Energy, Duke Energy Carolinas, Progress Energy, Duke Energy Progress, Duke Energy Florida, Duke Energy Ohio, Duke Energy Indiana and Piedmont (collectively the Duke Energy Registrants). Information contained herein relating to any individual registrant is filed by such registrant solely on its own behalf. Each registrant makes no representation as to information relating exclusively to the other registrants.
Entity Central Index Key	0001326160
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Common Stock
Document Information [Line Items]
Title of 12(b) Security	Common Stock, $0.001 par value
Trading Symbol	DUK
Security Exchange Name	NYSE
Junior Subordinated Debentures 5.125% Coupon Due January 2073
Document Information [Line Items]
Title of 12(b) Security	5.125% Junior Subordinated Debentures
Trading Symbol	DUKH
Security Exchange Name	NYSE
Junior Subordinated Debentures 5.625% Coupon Due September 2078
Document Information [Line Items]
Title of 12(b) Security	5.625% Junior Subordinated Debentures
Trading Symbol	DUKB
Security Exchange Name	NYSE
Depositary Share
Document Information [Line Items]
Title of 12(b) Security	Depositary Shares
Trading Symbol	DUK PR A
Security Exchange Name	NYSE
Duke Energy Carolinas
Document Information [Line Items]
Entity File Number	1-4928
Entity Registrant Name	DUKE ENERGY CAROLINAS, LLC
Entity Tax Identification Number	56-0205520
Entity Incorporation, State or Country Code	NC
Entity Address, Address Line One	526 South Church Street
Entity Address, City or Town	Charlotte
Entity Address, State or Province	NC
Entity Address, Postal Zip Code	28202-1803
City Area Code	704
Local Phone Number	382-3853
Entity Well-known Seasoned Issuer	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Central Index Key	0000030371
Progress Energy
Document Information [Line Items]
Entity File Number	1-15929
Entity Registrant Name	PROGRESS ENERGY, INC.
Entity Tax Identification Number	56-2155481
Entity Incorporation, State or Country Code	NC
Entity Address, Address Line One	410 South Wilmington Street
Entity Address, City or Town	Raleigh
Entity Address, State or Province	NC
Entity Address, Postal Zip Code	27601-1748
City Area Code	704
Local Phone Number	382-3853
Entity Well-known Seasoned Issuer	No
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Central Index Key	0001094093
Duke Energy Progress
Document Information [Line Items]
Entity File Number	1-3382
Entity Registrant Name	DUKE ENERGY PROGRESS, LLC
Entity Tax Identification Number	56-0165465
Entity Incorporation, State or Country Code	NC
Entity Address, Address Line One	410 South Wilmington Street
Entity Address, City or Town	Raleigh
Entity Address, State or Province	NC
Entity Address, Postal Zip Code	27601-1748
City Area Code	704
Local Phone Number	382-3853
Entity Well-known Seasoned Issuer	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Central Index Key	0000017797
Duke Energy Florida
Document Information [Line Items]
Entity File Number	1-3274
Entity Registrant Name	DUKE ENERGY FLORIDA, LLC
Entity Tax Identification Number	59-0247770
Entity Incorporation, State or Country Code	FL
Entity Address, Address Line One	299 First Avenue North
Entity Address, City or Town	St. Petersburg
Entity Address, State or Province	FL
Entity Address, Postal Zip Code	33701
City Area Code	704
Local Phone Number	382-3853
Entity Well-known Seasoned Issuer	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Central Index Key	0000037637
Duke Energy Ohio
Document Information [Line Items]
Entity File Number	1-1232
Entity Registrant Name	DUKE ENERGY OHIO, INC.
Entity Tax Identification Number	31-0240030
Entity Incorporation, State or Country Code	OH
Entity Address, Address Line One	139 East Fourth Street
Entity Address, City or Town	Cincinnati
Entity Address, State or Province	OH
Entity Address, Postal Zip Code	45202
City Area Code	704
Local Phone Number	382-3853
Entity Well-known Seasoned Issuer	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Central Index Key	0000020290
Duke Energy Indiana
Document Information [Line Items]
Entity File Number	1-3543
Entity Registrant Name	DUKE ENERGY INDIANA, LLC
Entity Tax Identification Number	35-0594457
Entity Incorporation, State or Country Code	IN
Entity Address, Address Line One	1000 East Main Street
Entity Address, City or Town	Plainfield
Entity Address, State or Province	IN
Entity Address, Postal Zip Code	46168
City Area Code	704
Local Phone Number	382-3853
Entity Well-known Seasoned Issuer	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Central Index Key	0000081020
Piedmont
Document Information [Line Items]
Entity File Number	1-6196
Entity Registrant Name	PIEDMONT NATURAL GAS COMPANY, INC.
Entity Tax Identification Number	56-0556998
Entity Incorporation, State or Country Code	NC
Entity Address, Address Line One	4720 Piedmont Row Drive
Entity Address, City or Town	Charlotte
Entity Address, State or Province	NC
Entity Address, Postal Zip Code	28210
City Area Code	704
Local Phone Number	364-3120
Entity Well-known Seasoned Issuer	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Central Index Key	0000078460

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating Revenues
Regulated electric		$ 21,461	$ 22,615	$ 22,097
Regulated natural gas		1,642	1,759	1,773
Nonregulated electric and other		765	705	651
Total operating revenues		23,868	25,079	24,521
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		6,051	6,826	6,831
Operation, maintenance and other		5,788	6,066	6,463
Depreciation and amortization		4,705	4,548	4,074
Property and other taxes		1,337	1,307	1,280
Impairment charges		984	(8)	402
Total operating expenses		19,325	19,366	19,747
Gains (Losses) on Sales of Other Assets and Other, net		10	(4)	(89)
Operating Income		4,553	5,709	4,685
Other Income and Expenses
Equity in (losses) earnings of unconsolidated affiliates		(2,005)	162	83
Other income and expenses, net		453	430	399
Total other income and expenses		(1,552)	592	482
Interest Expense		2,162	2,204	2,094
Income From Continuing Operations Before Income Taxes		839	4,097	3,073
Income Tax (Benefit) Expense From Continuing Operations		(236)	519	448
Income From Continuing Operations		1,075	3,578	2,625
Income (Loss) From Discontinued Operations, net of tax		7	(7)	19
Net Income		1,082	3,571	2,644
Add: Net Loss Attributable to Noncontrolling Interests		295	177	22
Net Income Attributable to Parent		1,377	3,748	2,666
Less: Preferred Dividends		107	41
Net Income Available to Common Stockholders		1,270	3,707	2,666
Other Comprehensive Income, net of tax
Pension and OPEB adjustments	[1]	6	9	(6)
Net unrealized gain on cash flow hedges	[1]	(138)	(47)	(10)
Reclassification into earnings from cash flow hedges	[1]	11	6	6
Unrealized (losses) gains on available-for-sale securities	[1]	3	8	(3)
Other Comprehensive Loss, net of tax	[1]	(118)	(24)	(13)
Comprehensive Income		964	3,547	2,631
Add: Comprehensive Loss Attributable to Noncontrolling Interests		(306)	(177)	(22)
Comprehensive Income		$ 1,163	$ 3,683	$ 2,653
Income from continuing operations available to Duke Energy Corporation common stockholders
Basic and diluted (usd per share)		$ 1.71	$ 5.07	$ 3.73
Income (Loss) from discontinued operations attributable to Duke Energy Corporation common stockholders
Basic and diluted (usd per share)		0.01	(0.01)	0.03
Net income available to Duke Energy Corporation common stockholders
Basic and diluted (usd per share)		$ 1.72	$ 5.06	$ 3.76
Weighted average shares outstanding
Basic (in shares)		737	729	708
Diluted (in shares)		738	729	708
Cost of natural gas
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		$ 460	$ 627	$ 697
Duke Energy Carolinas
Operating Revenues
Total operating revenues		7,015	7,395	7,300
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		1,682	1,804	1,821
Operation, maintenance and other		1,743	1,868	2,130
Depreciation and amortization		1,462	1,388	1,201
Property and other taxes		299	292	295
Impairment charges		476	17	192
Total operating expenses		5,662	5,369	5,639
Gains (Losses) on Sales of Other Assets and Other, net		1		(1)
Operating Income		1,354	2,026	1,660
Other Income and Expenses
Other income and expenses, net		177	151	153
Total other income and expenses		177	151	153
Interest Expense		487	463	439
Income From Continuing Operations Before Income Taxes		1,044	1,714	1,374
Income Tax (Benefit) Expense From Continuing Operations		88	311	303
Net Income Attributable to Parent		956	1,403	1,071
Other Comprehensive Income, net of tax
Reclassification into earnings from cash flow hedges				1
Other Comprehensive Loss, net of tax				1
Comprehensive Income		956	1,403	1,072
Progress Energy
Operating Revenues
Total operating revenues		10,627	11,202	10,728
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		3,479	4,024	3,976
Operation, maintenance and other		2,479	2,495	2,613
Depreciation and amortization		1,818	1,845	1,619
Property and other taxes		545	561	529
Impairment charges		495	(24)	87
Total operating expenses		8,816	8,901	8,824
Gains (Losses) on Sales of Other Assets and Other, net		9		24
Operating Income		1,820	2,301	1,928
Other Income and Expenses
Other income and expenses, net		129	141	165
Total other income and expenses		129	141	165
Interest Expense		790	862	842
Income Before Income Taxes		1,159	1,580	1,251
Income Tax (Benefit) Expense From Continuing Operations		113	253	218
Net Income		1,046	1,327	1,033
Add: Net Loss Attributable to Noncontrolling Interests		1		6
Net Income Attributable to Parent		1,045	1,327	1,027
Other Comprehensive Income, net of tax
Pension and OPEB adjustments		(1)	2	5
Net unrealized gain on cash flow hedges		5	5	6
Unrealized (losses) gains on available-for-sale securities		(1)	1	(1)
Other Comprehensive Loss, net of tax		3	8	10
Comprehensive Income		1,049	1,335	1,043
Add: Comprehensive Loss Attributable to Noncontrolling Interests		1		6
Comprehensive Income		1,048	1,335	1,037
Duke Energy Progress
Operating Revenues
Total operating revenues		5,422	5,957	5,699
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		1,743	2,012	1,892
Operation, maintenance and other		1,332	1,446	1,578
Depreciation and amortization		1,116	1,143	991
Property and other taxes		167	176	155
Impairment charges		499	12	33
Total operating expenses		4,857	4,789	4,649
Gains (Losses) on Sales of Other Assets and Other, net		8		9
Operating Income		573	1,168	1,059
Other Income and Expenses
Other income and expenses, net		75	100	87
Total other income and expenses		75	100	87
Interest Expense		269	306	319
Income From Continuing Operations Before Income Taxes		379	962	827
Income Tax (Benefit) Expense From Continuing Operations		(36)	157	160
Net Income Attributable to Parent		415	805	667
Other Comprehensive Income, net of tax
Comprehensive Income		415	805	667
Duke Energy Florida
Operating Revenues
Total operating revenues		5,188	5,231	5,021
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		1,737	2,012	2,085
Operation, maintenance and other		1,131	1,034	1,025
Depreciation and amortization		702	702	628
Property and other taxes		381	392	374
Impairment charges		(4)	(36)	54
Total operating expenses		3,947	4,104	4,166
Gains (Losses) on Sales of Other Assets and Other, net		1		1
Operating Income		1,242	1,127	856
Other Income and Expenses
Other income and expenses, net		53	48	86
Total other income and expenses		53	48	86
Interest Expense		326	328	287
Income From Continuing Operations Before Income Taxes		969	847	655
Income Tax (Benefit) Expense From Continuing Operations		198	155	101
Net Income Attributable to Parent		771	692	554
Other Comprehensive Income, net of tax
Unrealized (losses) gains on available-for-sale securities		(1)	1	(1)
Other Comprehensive Loss, net of tax		(1)	1	(1)
Comprehensive Income		770	693	553
Duke Energy Ohio
Operating Revenues
Regulated electric		1,405	1,456	1,450
Regulated natural gas		453	484	506
Nonregulated electric and other				1
Total operating revenues		1,858	1,940	1,957
Operating Expenses
Operation, maintenance and other		463	520	480
Depreciation and amortization		278	265	268
Property and other taxes		324	308	290
Total operating expenses		1,477	1,576	1,563
Gains (Losses) on Sales of Other Assets and Other, net				(106)
Operating Income		381	364	288
Other Income and Expenses
Other income and expenses, net		16	24	23
Total other income and expenses		16	24	23
Interest Expense		102	109	92
Income From Continuing Operations Before Income Taxes		295	279	219
Income Tax (Benefit) Expense From Continuing Operations		43	40	43
Income From Continuing Operations		252	239	176
Income (Loss) From Discontinued Operations, net of tax			(1)
Net Income Attributable to Parent		252	238	176
Other Comprehensive Income, net of tax
Comprehensive Income		252	238	176
Duke Energy Ohio | Cost of natural gas
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		73	95	113
Duke Energy Ohio | Electric Utilities and Infrastructure
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		339	388	412
Duke Energy Indiana
Operating Revenues
Total operating revenues		2,795	3,004	3,059
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		767	935	1,000
Operation, maintenance and other		762	790	788
Depreciation and amortization		569	525	520
Property and other taxes		81	69	78
Impairment charges				30
Total operating expenses		2,179	2,319	2,416
Operating Income		616	685	643
Other Income and Expenses
Other income and expenses, net		37	41	45
Total other income and expenses		37	41	45
Interest Expense		161	156	167
Income From Continuing Operations Before Income Taxes		492	570	521
Income Tax (Benefit) Expense From Continuing Operations		84	134	128
Net Income Attributable to Parent		408	436	393
Piedmont
Operating Revenues
Regulated natural gas		1,286	1,369	1,365
Nonregulated electric and other		11	12	10
Total operating revenues		1,297	1,381	1,375
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		386	532	584
Operation, maintenance and other		322	328	357
Depreciation and amortization		180	172	159
Property and other taxes		53	45	49
Impairment charges		7
Total operating expenses		948	1,077	1,149
Operating Income		349	304	226
Other Income and Expenses
Equity in (losses) earnings of unconsolidated affiliates		9	8	7
Other income and expenses, net		51	20	14
Total other income and expenses		60	28	21
Interest Expense		118	87	81
Income From Continuing Operations Before Income Taxes		291	245	166
Income Tax (Benefit) Expense From Continuing Operations		18	43	37
Net Income Attributable to Parent		273	202	129
Other Comprehensive Income, net of tax
Comprehensive Income		$ 273	$ 202	$ 129
[1]	Net of income tax impacts of approximately $35 million for the year ended December 31, 2020. Tax impacts are immaterial for other periods presented.

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income		$ 1,082	$ 3,571	$ 2,644
Other Comprehensive Income, net of tax
Pension and OPEB adjustments	[1]	6	9	(6)
Net unrealized losses on cash flow hedges	[1]	(138)	(47)	(10)
Reclassification into earnings from cash flow hedges	[1]	11	6	6
Unrealized gains (losses) on available-for-sale securities	[1]	3	8	(3)
Other Comprehensive Loss, net of tax	[1]	(118)	(24)	(13)
Comprehensive Income		964	3,547	2,631
Add: Comprehensive Loss Attributable to Noncontrolling Interests		306	177	22
Comprehensive Income Attributable to Duke Energy Corporation		1,270	3,724	2,653
Less: Preferred Dividends		107	41
Comprehensive Income		1,163	$ 3,683	$ 2,653
Other comprehensive income (loss), tax		$ 35
[1]	Net of income tax impacts of approximately $35 million for the year ended December 31, 2020. Tax impacts are immaterial for other periods presented.

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Current Assets
Cash and cash equivalents	$ 259	$ 311
Receivables (net of allowance for doubtful accounts)	1,009	1,066
Receivables of VIEs (net of allowance for doubtful accounts)	2,144	1,994
Inventory	3,167	3,232
Regulatory assets (includes amounts related to VIEs)	1,641	1,796
Other (including amounts related to VIEs)	462	764
Total current assets	8,682	9,163
Property, Plant and Equipment
Cost	155,580	147,654
Accumulated depreciation and amortization	(48,827)	(45,773)
Generation facilities to be retired, net	29	246
Net property, plant and equipment	106,782	102,127
Other Noncurrent Assets
Goodwill	19,303	19,303
Regulatory assets (includes amounts related to VIEs)	12,421	13,222
Nuclear decommissioning trust funds	9,114	8,140
Operating lease right-of-use assets, net	1,524	1,658
Investments in equity method unconsolidated affiliates	961	1,936
Other (including amounts related to VIEs)	3,601	3,289
Total other noncurrent assets	46,924	47,548
Total Assets	162,388	158,838
Current Liabilities
Accounts payable	3,144	3,487
Notes payable and commercial paper	2,873	3,135
Taxes accrued	482	392
Interest accrued	537	565
Current maturities of long-term debt (includes amounts related to VIEs)	4,238	3,141
Asset retirement obligations	718	881
Regulatory liabilities	1,377	784
Other	2,936	2,367
Total current liabilities	16,305	14,752
Long-Term Debt (includes amounts related to VIEs)	55,625	54,985
Other Noncurrent Liabilities
Deferred income taxes	9,244	8,878
Asset retirement obligations	12,286	12,437
Regulatory liabilities	15,029	15,264
Operating lease liabilities	1,340	1,432
Accrued pension and other post-retirement benefit costs	969	934
Investment tax credits	687	624
Other (includes amounts related to VIEs)	1,719	1,581
Total other noncurrent liabilities	41,274	41,150
Commitments and Contingencies
Equity
Common stock	1	1
Additional paid-in capital	43,767	40,881
Retained earnings	2,471	4,108
Accumulated other comprehensive (loss) income	(237)	(130)
Total Parent stockholders' equity	47,964	46,822
Noncontrolling interests	1,220	1,129
Total equity	49,184	47,951
Total Liabilities and Equity	162,388	158,838
VIEs
Current Assets
Regulatory assets (includes amounts related to VIEs)	53	52
Other (including amounts related to VIEs)	296	242
Other Noncurrent Assets
Regulatory assets (includes amounts related to VIEs)	937	989
Other (including amounts related to VIEs)	81	110
Current Liabilities
Current maturities of long-term debt (includes amounts related to VIEs)	472	216
Long-Term Debt (includes amounts related to VIEs)	3,535	3,997
Other Noncurrent Liabilities
Other (includes amounts related to VIEs)	316	228
Series A Preferred Stock
Equity
Preferred stock	973	973
Series B Preferred Stock
Equity
Preferred stock	989	989
Duke Energy Carolinas
Current Assets
Cash and cash equivalents	21	18
Receivables (net of allowance for doubtful accounts)	247	324
Receivables of VIEs (net of allowance for doubtful accounts)	696	642
Receivables from affiliated companies	124	114
Inventory	1,010	996
Regulatory assets (includes amounts related to VIEs)	473	550
Other (including amounts related to VIEs)	20	21
Total current assets	2,591	2,665
Property, Plant and Equipment
Cost	50,640	48,922
Accumulated depreciation and amortization	(17,453)	(16,525)
Net property, plant and equipment	33,187	32,397
Other Noncurrent Assets
Regulatory assets (includes amounts related to VIEs)	2,996	3,360
Nuclear decommissioning trust funds	4,977	4,359
Operating lease right-of-use assets, net	110	123
Other (including amounts related to VIEs)	1,187	1,149
Total other noncurrent assets	9,270	8,991
Total Assets	45,048	44,053
Current Liabilities
Accounts payable	1,000	954
Accounts payable to affiliated companies	199	210
Notes payable to affiliated companies	506	29
Taxes accrued	76	46
Interest accrued	117	115
Current maturities of long-term debt (includes amounts related to VIEs)	506	458
Asset retirement obligations	264	206
Regulatory liabilities	473	255
Other	546	611
Total current liabilities	3,687	2,884
Long-Term Debt (includes amounts related to VIEs)	11,412	11,142
Long-Term Debt Payable to Affiliated Companies	300	300
Other Noncurrent Liabilities
Deferred income taxes	3,842	3,921
Asset retirement obligations	5,086	5,528
Regulatory liabilities	6,535	6,423
Operating lease liabilities	97	102
Accrued pension and other post-retirement benefit costs	73	84
Investment tax credits	236	231
Other (includes amounts related to VIEs)	626	627
Total other noncurrent liabilities	16,495	16,916
Commitments and Contingencies
Equity
Member's equity	13,161	12,818
Accumulated other comprehensive (loss) income	(7)	(7)
Total member's equity	13,154	12,811
Total Liabilities and Equity	45,048	44,053
Progress Energy
Current Assets
Cash and cash equivalents	59	48
Receivables (net of allowance for doubtful accounts)	228	220
Receivables of VIEs (net of allowance for doubtful accounts)	901	830
Receivables from affiliated companies	157	76
Notes receivable from affiliated companies		164
Inventory	1,375	1,423
Regulatory assets (includes amounts related to VIEs)	758	946
Other (including amounts related to VIEs)	109	210
Total current assets	3,587	3,917
Property, Plant and Equipment
Cost	57,892	55,070
Accumulated depreciation and amortization	(18,368)	(17,159)
Generation facilities to be retired, net	29	246
Net property, plant and equipment	39,553	38,157
Other Noncurrent Assets
Goodwill	3,655	3,655
Regulatory assets (includes amounts related to VIEs)	5,775	6,346
Nuclear decommissioning trust funds	4,137	3,782
Operating lease right-of-use assets, net	690	788
Other (including amounts related to VIEs)	1,227	1,049
Total other noncurrent assets	15,484	15,620
Total Assets	58,624	57,694
Current Liabilities
Accounts payable	919	1,104
Accounts payable to affiliated companies	289	310
Notes payable to affiliated companies	2,969	1,821
Taxes accrued	121	46
Interest accrued	202	228
Current maturities of long-term debt (includes amounts related to VIEs)	1,426	1,577
Asset retirement obligations	283	485
Regulatory liabilities	640	330
Other	793	902
Total current liabilities	7,642	6,803
Long-Term Debt (includes amounts related to VIEs)	17,688	17,907
Long-Term Debt Payable to Affiliated Companies	150	150
Other Noncurrent Liabilities
Deferred income taxes	4,396	4,462
Asset retirement obligations	5,866	5,986
Regulatory liabilities	5,051	5,225
Operating lease liabilities	623	697
Accrued pension and other post-retirement benefit costs	505	488
Other (includes amounts related to VIEs)	462	383
Total other noncurrent liabilities	16,903	17,241
Commitments and Contingencies
Equity
Additional paid-in capital	9,143	9,143
Retained earnings	7,109	6,465
Accumulated other comprehensive (loss) income	(15)	(18)
Total Parent stockholders' equity	16,237	15,590
Noncontrolling interests	4	3
Total equity	16,241	15,593
Total Liabilities and Equity	58,624	57,694
Progress Energy | VIEs
Current Assets
Regulatory assets (includes amounts related to VIEs)	53	52
Other (including amounts related to VIEs)	39	39
Other Noncurrent Assets
Regulatory assets (includes amounts related to VIEs)	937	989
Current Liabilities
Current maturities of long-term debt (includes amounts related to VIEs)	305	54
Long-Term Debt (includes amounts related to VIEs)	1,252	1,632
Duke Energy Progress
Current Assets
Cash and cash equivalents	39	22
Receivables (net of allowance for doubtful accounts)	132	123
Receivables of VIEs (net of allowance for doubtful accounts)	500	489
Receivables from affiliated companies	50	52
Inventory	911	934
Regulatory assets (includes amounts related to VIEs)	492	526
Other (including amounts related to VIEs)	60	60
Total current assets	2,184	2,206
Property, Plant and Equipment
Cost	35,759	34,603
Accumulated depreciation and amortization	(12,801)	(11,915)
Generation facilities to be retired, net	29	246
Net property, plant and equipment	22,987	22,934
Other Noncurrent Assets
Regulatory assets (includes amounts related to VIEs)	3,976	4,152
Nuclear decommissioning trust funds	3,500	3,047
Operating lease right-of-use assets, net	346	387
Other (including amounts related to VIEs)	740	651
Total other noncurrent assets	8,562	8,237
Total Assets	33,733	33,377
Current Liabilities
Accounts payable	454	629
Accounts payable to affiliated companies	215	203
Notes payable to affiliated companies	295	66
Taxes accrued	85	17
Interest accrued	99	110
Current maturities of long-term debt (includes amounts related to VIEs)	603	1,006
Asset retirement obligations	283	485
Regulatory liabilities	530	236
Other	411	478
Total current liabilities	2,975	3,230
Long-Term Debt (includes amounts related to VIEs)	8,505	7,902
Long-Term Debt Payable to Affiliated Companies	150	150
Other Noncurrent Liabilities
Deferred income taxes	2,298	2,388
Asset retirement obligations	5,352	5,408
Regulatory liabilities	4,394	4,232
Operating lease liabilities	323	354
Accrued pension and other post-retirement benefit costs	242	238
Investment tax credits	132	137
Other (includes amounts related to VIEs)	102	92
Total other noncurrent liabilities	12,843	12,849
Commitments and Contingencies
Equity
Total member's equity	9,260	9,246
Total Liabilities and Equity	33,733	33,377
Duke Energy Florida
Current Assets
Cash and cash equivalents	11	17
Receivables (net of allowance for doubtful accounts)	94	96
Receivables of VIEs (net of allowance for doubtful accounts)	401	341
Receivables from affiliated companies	3
Notes receivable from affiliated companies		173
Inventory	464	489
Regulatory assets (includes amounts related to VIEs)	265	419
Other (including amounts related to VIEs)	41	58
Total current assets	1,279	1,593
Property, Plant and Equipment
Cost	22,123	20,457
Accumulated depreciation and amortization	(5,560)	(5,236)
Net property, plant and equipment	16,563	15,221
Other Noncurrent Assets
Regulatory assets (includes amounts related to VIEs)	1,799	2,194
Nuclear decommissioning trust funds	637	734
Operating lease right-of-use assets, net	344	401
Other (including amounts related to VIEs)	335	311
Total other noncurrent assets	3,115	3,640
Total Assets	20,957	20,454
Current Liabilities
Accounts payable	465	474
Accounts payable to affiliated companies	85	131
Notes payable to affiliated companies	196
Taxes accrued	82	43
Interest accrued	69	75
Current maturities of long-term debt (includes amounts related to VIEs)	823	571
Regulatory liabilities	110	94
Other	374	415
Total current liabilities	2,204	1,803
Long-Term Debt (includes amounts related to VIEs)	7,092	7,416
Other Noncurrent Liabilities
Deferred income taxes	2,191	2,179
Asset retirement obligations	514	578
Regulatory liabilities	658	993
Operating lease liabilities	300	343
Accrued pension and other post-retirement benefit costs	231	218
Other (includes amounts related to VIEs)	209	136
Total other noncurrent liabilities	4,103	4,447
Commitments and Contingencies
Equity
Member's equity	7,560	6,789
Accumulated other comprehensive (loss) income	(2)	(1)
Total member's equity	7,558	6,788
Total Liabilities and Equity	20,957	20,454
Duke Energy Florida | VIEs
Current Assets
Regulatory assets (includes amounts related to VIEs)	53	52
Other (including amounts related to VIEs)	39
Other Noncurrent Assets
Regulatory assets (includes amounts related to VIEs)	937	989
Current Liabilities
Current maturities of long-term debt (includes amounts related to VIEs)	305	54
Long-Term Debt (includes amounts related to VIEs)	1,002	1,307
Duke Energy Ohio
Current Assets
Cash and cash equivalents	14	17
Receivables (net of allowance for doubtful accounts)	98	84
Receivables from affiliated companies	102	92
Inventory	110	135
Regulatory assets (includes amounts related to VIEs)	39	49
Other (including amounts related to VIEs)	31	21
Total current assets	394	398
Property, Plant and Equipment
Cost	11,022	10,241
Accumulated depreciation and amortization	(3,013)	(2,843)
Net property, plant and equipment	8,009	7,398
Other Noncurrent Assets
Goodwill	920	920
Regulatory assets (includes amounts related to VIEs)	610	549
Operating lease right-of-use assets, net	20	21
Other (including amounts related to VIEs)	72	52
Total other noncurrent assets	1,622	1,542
Total Assets	10,025	9,338
Current Liabilities
Accounts payable	279	288
Accounts payable to affiliated companies	68	68
Notes payable to affiliated companies	169	312
Taxes accrued	247	219
Interest accrued	31	30
Current maturities of long-term debt (includes amounts related to VIEs)	50
Asset retirement obligations	3	1
Regulatory liabilities	65	64
Other	70	75
Total current liabilities	982	1,057
Long-Term Debt (includes amounts related to VIEs)	3,014	2,594
Long-Term Debt Payable to Affiliated Companies	25	25
Other Noncurrent Liabilities
Deferred income taxes	981	922
Asset retirement obligations	108	79
Regulatory liabilities	748	763
Operating lease liabilities	20	21
Accrued pension and other post-retirement benefit costs	113	100
Other (includes amounts related to VIEs)	99	94
Total other noncurrent liabilities	2,069	1,979
Commitments and Contingencies
Equity
Common stock	762	762
Additional paid-in capital	2,776	2,776
Retained earnings	397	145
Total Parent stockholders' equity	3,935	3,683
Total Liabilities and Equity	10,025	9,338
Duke Energy Indiana
Current Assets
Cash and cash equivalents	7	25
Receivables (net of allowance for doubtful accounts)	55	60
Receivables from affiliated companies	112	79
Inventory	473	517
Regulatory assets (includes amounts related to VIEs)	125	90
Other (including amounts related to VIEs)	37	60
Total current assets	809	831
Property, Plant and Equipment
Cost	17,382	16,305
Accumulated depreciation and amortization	(5,661)	(5,233)
Net property, plant and equipment	11,721	11,072
Other Noncurrent Assets
Regulatory assets (includes amounts related to VIEs)	1,203	1,082
Operating lease right-of-use assets, net	55	57
Other (including amounts related to VIEs)	253	234
Total other noncurrent assets	1,511	1,373
Total Assets	14,041	13,276
Current Liabilities
Accounts payable	188	201
Accounts payable to affiliated companies	88	87
Notes payable to affiliated companies	131	30
Taxes accrued	62	49
Interest accrued	51	58
Current maturities of long-term debt (includes amounts related to VIEs)	70	503
Asset retirement obligations	168	189
Regulatory liabilities	111	55
Other	83	112
Total current liabilities	952	1,284
Long-Term Debt (includes amounts related to VIEs)	3,871	3,404
Long-Term Debt Payable to Affiliated Companies	150	150
Other Noncurrent Liabilities
Deferred income taxes	1,228	1,150
Asset retirement obligations	1,008	643
Regulatory liabilities	1,627	1,685
Operating lease liabilities	53	55
Accrued pension and other post-retirement benefit costs	171	148
Investment tax credits	168	164
Other (includes amounts related to VIEs)	30	18
Total other noncurrent liabilities	4,285	3,863
Commitments and Contingencies
Equity
Total member's equity	4,783	4,575
Total Liabilities and Equity	14,041	13,276
Piedmont
Current Assets
Receivables (net of allowance for doubtful accounts)	250	241
Receivables from affiliated companies	10	10
Inventory	68	72
Regulatory assets (includes amounts related to VIEs)	153	73
Other (including amounts related to VIEs)	20	28
Total current assets	501	424
Property, Plant and Equipment
Cost	9,134	8,446
Accumulated depreciation and amortization	(1,749)	(1,681)
Net property, plant and equipment	7,385	6,765
Other Noncurrent Assets
Goodwill	49	49
Regulatory assets (includes amounts related to VIEs)	302	290
Operating lease right-of-use assets, net	20	24
Investments in equity method unconsolidated affiliates	88	83
Other (including amounts related to VIEs)	270	121
Total other noncurrent assets	729	567
Total Assets	8,615	7,756
Current Liabilities
Accounts payable	230	215
Accounts payable to affiliated companies	79	3
Notes payable to affiliated companies	530	476
Taxes accrued	23	24
Interest accrued	34	33
Current maturities of long-term debt (includes amounts related to VIEs)	160	0
Regulatory liabilities	88	81
Other	69	67
Total current liabilities	1,213	899
Long-Term Debt (includes amounts related to VIEs)	2,620	2,384
Other Noncurrent Liabilities
Deferred income taxes	821	708
Asset retirement obligations	20	17
Regulatory liabilities	1,044	1,131
Operating lease liabilities	19	23
Accrued pension and other post-retirement benefit costs	8	3
Other (includes amounts related to VIEs)	155	148
Total other noncurrent liabilities	2,067	2,030
Commitments and Contingencies
Equity
Common stock	1,310	1,310
Retained earnings	1,405	1,133
Total Parent stockholders' equity	2,715	2,443
Total Liabilities and Equity	$ 8,615	$ 7,756

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Allowance for doubtful accounts - receivables	$ 29	$ 22
Regulatory Assets: Current	1,641	1,796
Current Assets: Other	462	764
Other Noncurrent Assets: Regulatory assets	12,421	13,222
Other Noncurrent Assets: Other	3,601	3,289
Current maturities of long-term debt	4,238	3,141
Long-term debt	55,625	54,985
Other Noncurrent Liabilities: Other	$ 1,719	$ 1,581
Preferred stock, par value (in usd per share)	$ 0
Common stock, par value (usd per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	2,000,000,000
Common stock, shares outstanding (in shares)	769,000,000	733,000,000
VIEs
Allowance for doubtful accounts - receivables of VIEs	$ 117	$ 54
Regulatory Assets: Current	53	52
Current Assets: Other	296	242
Other Noncurrent Assets: Regulatory assets	937	989
Other Noncurrent Assets: Other	81	110
Current maturities of long-term debt	472	216
Long-term debt	3,535	3,997
Other Noncurrent Liabilities: Other	$ 316	$ 228
Series A Preferred Stock
Preferred stock, par value (in usd per share)	$ 0.001	$ 0.001
Preferred stock, depositary shares authorized (in shares)	40,000,000	40,000,000
Preferred stock, depositary shares outstanding (in shares)	40,000,000	40,000,000
Series B Preferred Stock
Preferred stock, par value (in usd per share)	$ 0.001	$ 0.001
Preferred stock, depositary shares authorized (in shares)	1,000,000	1,000,000
Preferred stock, depositary shares outstanding (in shares)	1,000,000	1,000,000
Duke Energy Carolinas
Allowance for doubtful accounts - receivables	$ 1	$ 3
Regulatory Assets: Current	473	550
Current Assets: Other	20	21
Other Noncurrent Assets: Regulatory assets	2,996	3,360
Other Noncurrent Assets: Other	1,187	1,149
Current maturities of long-term debt	506	458
Long-term debt	11,412	11,142
Other Noncurrent Liabilities: Other	626	627
Duke Energy Carolinas | VIEs
Allowance for doubtful accounts - receivables of VIEs	22	7
Progress Energy
Allowance for doubtful accounts - receivables	8	7
Regulatory Assets: Current	758	946
Current Assets: Other	109	210
Other Noncurrent Assets: Regulatory assets	5,775	6,346
Other Noncurrent Assets: Other	1,227	1,049
Current maturities of long-term debt	1,426	1,577
Long-term debt	17,688	17,907
Other Noncurrent Liabilities: Other	$ 462	$ 383
Common stock, par value (usd per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	100	100
Common stock, shares outstanding (in shares)	100	100
Progress Energy | VIEs
Allowance for doubtful accounts - receivables of VIEs	$ 29	$ 9
Regulatory Assets: Current	53	52
Current Assets: Other	39	39
Other Noncurrent Assets: Regulatory assets	937	989
Current maturities of long-term debt	305	54
Long-term debt	1,252	1,632
Duke Energy Progress
Allowance for doubtful accounts - receivables	4	3
Regulatory Assets: Current	492	526
Current Assets: Other	60	60
Other Noncurrent Assets: Regulatory assets	3,976	4,152
Other Noncurrent Assets: Other	740	651
Current maturities of long-term debt	603	1,006
Long-term debt	8,505	7,902
Other Noncurrent Liabilities: Other	102	92
Duke Energy Progress | VIEs
Allowance for doubtful accounts - receivables of VIEs	19	5
Duke Energy Florida
Allowance for doubtful accounts - receivables	4	3
Regulatory Assets: Current	265	419
Current Assets: Other	41	58
Other Noncurrent Assets: Regulatory assets	1,799	2,194
Other Noncurrent Assets: Other	335	311
Current maturities of long-term debt	823	571
Long-term debt	7,092	7,416
Other Noncurrent Liabilities: Other	209	136
Duke Energy Florida | VIEs
Allowance for doubtful accounts - receivables of VIEs	10	4
Regulatory Assets: Current	53	52
Current Assets: Other	39
Other Noncurrent Assets: Regulatory assets	937	989
Current maturities of long-term debt	305	54
Long-term debt	1,002	1,307
Duke Energy Ohio
Allowance for doubtful accounts - receivables	4	4
Regulatory Assets: Current	39	49
Current Assets: Other	31	21
Other Noncurrent Assets: Regulatory assets	610	549
Other Noncurrent Assets: Other	72	52
Current maturities of long-term debt	50
Long-term debt	3,014	2,594
Other Noncurrent Liabilities: Other	$ 99	$ 94
Common stock, par value (usd per share)	$ 8.50	$ 8.50
Common stock, shares authorized (in shares)	120,000,000	120,000,000
Common stock, shares outstanding (in shares)	90,000,000	90,000,000
Duke Energy Indiana
Allowance for doubtful accounts - receivables	$ 3	$ 3
Regulatory Assets: Current	125	90
Current Assets: Other	37	60
Other Noncurrent Assets: Regulatory assets	1,203	1,082
Other Noncurrent Assets: Other	253	234
Current maturities of long-term debt	70	503
Long-term debt	3,871	3,404
Other Noncurrent Liabilities: Other	30	18
Piedmont
Allowance for doubtful accounts - receivables	12	6
Regulatory Assets: Current	153	73
Current Assets: Other	20	28
Other Noncurrent Assets: Regulatory assets	302	290
Other Noncurrent Assets: Other	270	121
Current maturities of long-term debt	160	0
Long-term debt	2,620	2,384
Other Noncurrent Liabilities: Other	$ 155	$ 148
Common stock, shares authorized (in shares)	100	100
Common stock, shares outstanding (in shares)	100	100

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 1,082	$ 3,571	$ 2,644
Net (loss) income attributable to Duke Energy	1,377	3,748	2,666
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	5,486	5,176	4,696
Equity in losses (earnings) of unconsolidated affiliates	2,005	(162)	(83)
Equity component of AFUDC	(154)	(139)	(221)
(Gains) Losses on sales of other assets	10	(4)	(88)
Impairment charges	984	(8)	402
Deferred income taxes	54	806	1,079
Payments for asset retirement obligations	(610)	(746)	(533)
Payment for the disposal of other assets			(105)
Provision for rate refunds	(22)	60	425
Refund of AMT credit carryforwards	572	573
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	63	(48)	22
Receivables	(56)	78	(345)
Inventory	66	(122)	156
Other current assets	205	10	(721)
Increase (decrease) in
Accounts payable	(21)	(164)	479
Taxes accrued	117	(224)	23
Other current liabilities	(65)	172	270
Other assets	(398)	(559)	(1,062)
Other liabilities	(442)	(69)	(28)
Net cash provided by (used in) operating activities	8,856	8,209	7,186
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(9,907)	(11,122)	(9,389)
Contributions to equity method investments	(370)	(324)	(416)
Return of investment capital	133	11	137
Purchases of debt and equity securities	(8,011)	(3,348)	(3,762)
Proceeds from sales and maturities of debt and equity securities	7,949	3,343	3,747
Other	(398)	(517)	(377)
Net cash used in investing activities	(10,604)	(11,957)	(10,060)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	6,330	7,091	5,299
Net proceeds from Issuance of Preferred Stock and Preference Stock		1,962
Proceeds from Issuance of Common Stock	2,745	384	1,838
Payments for the redemption of long-term debt	(4,506)	(3,476)	(2,906)
Proceeds from the issuance of short-term debt with original maturities greater than 90 days	3,009	397	472
Payments for the redemption of short-term debt with original maturities greater than 90 days	(2,147)	(479)	(282)
Notes payable and commercial paper	(1,181)	(298)	981
Contributions from noncontrolling interests	426	843	41
Dividends paid	(2,812)	(2,668)	(2,471)
Other	(133)	(26)	(12)
Net cash provided by financing activities	1,731	3,730	2,960
Net (decrease) increase in cash, cash equivalents, and restricted cash	(17)	(18)	86
Cash, cash equivalents, and restricted cash at beginning of period	573	591	505
Cash, cash equivalents, and restricted cash at end of period	556	573	591
Cash and cash equivalents at beginning of period	311
Cash and cash equivalents at end of period	259	311
Supplemental Disclosures:
Cash paid for interest, net of amount capitalized	2,186	2,195	2,086
Cash received from income taxes	(585)	(651)	(266)
Significant non-cash transactions:
Accrued capital expenditures	1,116	1,356	1,112
Non-cash dividends	110	108	107
Duke Energy Carolinas
CASH FLOWS FROM OPERATING ACTIVITIES
Net (loss) income attributable to Duke Energy	956	1,403	1,071
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	1,731	1,671	1,487
Equity component of AFUDC	(62)	(42)	(73)
(Gains) Losses on sales of other assets	1		(1)
Impairment charges	476	17	192
Deferred income taxes	(260)	133	305
Payments for asset retirement obligations	(162)	(278)	(230)
Provision for rate refunds	(5)	36	182
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	(4)	(8)	2
Receivables	52	(21)	(86)
Receivables from affiliated companies	(10)	68	(87)
Inventory	(14)	(48)	25
Other current assets	209	(73)	(161)
Increase (decrease) in
Accounts payable	55	(50)	168
Accounts payable to affiliated companies	(11)	(20)	21
Taxes accrued	30	(127)	(65)
Other current liabilities	(56)	127	89
Other assets	(101)	(42)	(221)
Other liabilities	(47)	(37)	(90)
Net cash provided by (used in) operating activities	2,776	2,709	2,530
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(2,669)	(2,714)	(2,706)
Purchases of debt and equity securities	(1,602)	(1,658)	(1,810)
Proceeds from sales and maturities of debt and equity securities	1,602	1,658	1,810
Other	(164)	(204)	(147)
Net cash used in investing activities	(2,833)	(2,918)	(2,853)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	998	886	1,983
Payments for the redemption of long-term debt	(813)	(6)	(1,205)
Notes payable to affiliated companies	477	(410)	335
Distributions to parent	(600)	(275)	(750)
Other	(2)	(1)	(23)
Net cash provided by financing activities	60	194	340
Net increase (decrease) in cash and cash equivalents	3	(15)	17
Cash and cash equivalents at beginning of period	18	33	16
Cash and cash equivalents at end of period	21	18	33
Supplemental Disclosures:
Cash paid for interest, net of amount capitalized	481	433	452
Cash received from income taxes	321	122	89
Significant non-cash transactions:
Accrued capital expenditures	365	347	302
Progress Energy
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	1,046	1,327	1,033
Net (loss) income attributable to Duke Energy	1,045	1,327	1,027
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	2,327	2,207	1,987
Equity component of AFUDC	(42)	(66)	(104)
(Gains) Losses on sales of other assets	9		24
Impairment charges	495	(24)	87
Deferred income taxes	(197)	433	358
Payments for asset retirement obligations	(384)	(412)	(230)
Provision for rate refunds	2	15	122
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	(9)	(34)	18
Receivables	(69)	47	(207)
Receivables from affiliated companies	(81)	81	(137)
Inventory	49	62	121
Other current assets	223	184	(12)
Increase (decrease) in
Accounts payable	(62)	(4)	217
Accounts payable to affiliated companies	(21)	(50)	109
Taxes accrued	75	(74)	8
Other current liabilities	139	25	129
Other assets	(128)	(341)	(896)
Other liabilities	(177)	(167)	(35)
Net cash provided by (used in) operating activities	3,177	3,209	2,544
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(3,488)	(3,952)	(3,854)
Purchases of debt and equity securities	(5,998)	(1,511)	(1,753)
Proceeds from sales and maturities of debt and equity securities	6,010	1,504	1,769
Notes receivable from affiliated companies	164	(164)	240
Other	(160)	(190)	(162)
Net cash used in investing activities	(3,472)	(4,313)	(3,760)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	1,791	2,187	1,833
Payments for the redemption of long-term debt	(2,157)	(1,667)	(771)
Notes payable to affiliated companies	1,148	586	430
Dividends to parent	(400)		(250)
Other	(13)	12	(1)
Net cash provided by financing activities	369	1,118	1,241
Net (decrease) increase in cash, cash equivalents, and restricted cash	74	14	25
Cash, cash equivalents, and restricted cash at beginning of period	126	112	87
Cash, cash equivalents, and restricted cash at end of period	200	126	112
Cash and cash equivalents at beginning of period	48
Cash and cash equivalents at end of period	59	48
Supplemental Disclosures:
Cash paid for interest, net of amount capitalized	819	892	798
Cash received from income taxes	149	(79)	(348)
Significant non-cash transactions:
Accrued capital expenditures	363	447	478
Duke Energy Progress
CASH FLOWS FROM OPERATING ACTIVITIES
Net (loss) income attributable to Duke Energy	415	805	667
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	1,299	1,329	1,183
Equity component of AFUDC	(29)	(60)	(57)
(Gains) Losses on sales of other assets	8		9
Impairment charges	499	12	33
Deferred income taxes	(234)	197	236
Payments for asset retirement obligations	(304)	(390)	(195)
Provision for rate refunds	2	12	122
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	1	(6)	5
Receivables	(4)	21	(107)
Receivables from affiliated companies	2	(29)	(20)
Inventory	23	20	63
Other current assets	98	101	(201)
Increase (decrease) in
Accounts payable	(127)	32	219
Accounts payable to affiliated companies	12	(75)	99
Taxes accrued	68	(46)	(11)
Other current liabilities	157	68	46
Other assets	(207)	(205)	(465)
Other liabilities	3	37	20
Net cash provided by (used in) operating activities	1,666	1,823	1,628
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(1,581)	(2,108)	(2,220)
Purchases of debt and equity securities	(1,555)	(842)	(1,236)
Proceeds from sales and maturities of debt and equity securities	1,516	810	1,206
Other	(57)	(119)	(95)
Net cash used in investing activities	(1,677)	(2,259)	(2,345)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	1,296	1,269	845
Payments for the redemption of long-term debt	(1,085)	(605)	(3)
Notes payable to affiliated companies	229	(228)	54
Distributions to parent	(400)		(175)
Other	(12)	(1)	(1)
Net cash provided by financing activities	28	435	720
Net increase (decrease) in cash and cash equivalents	17	(1)	3
Cash and cash equivalents at beginning of period	22	23	20
Cash and cash equivalents at end of period	39	22	23
Supplemental Disclosures:
Cash paid for interest, net of amount capitalized	301	331	303
Cash received from income taxes	123	(30)	(112)
Significant non-cash transactions:
Accrued capital expenditures	149	175	220
Duke Energy Florida
CASH FLOWS FROM OPERATING ACTIVITIES
Net (loss) income attributable to Duke Energy	771	692	554
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	1,019	869	793
Equity component of AFUDC	(12)	(6)	(47)
(Gains) Losses on sales of other assets	1		1
Impairment charges	(4)	(36)	54
Deferred income taxes	27	180	159
Payments for asset retirement obligations	(80)	(22)	(35)
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	(14)	(33)	7
Receivables	(64)	26	(100)
Receivables from affiliated companies	(3)	17	(26)
Inventory	26	42	58
Other current assets	40	156	59
Increase (decrease) in
Accounts payable	66	(36)	(1)
Accounts payable to affiliated companies	(46)	40	17
Taxes accrued	39	(31)	40
Other current liabilities	(7)	(36)	82
Other assets	85	(131)	(429)
Other liabilities	(181)	(213)	(75)
Net cash provided by (used in) operating activities	1,661	1,478	1,109
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(1,907)	(1,844)	(1,634)
Purchases of debt and equity securities	(4,443)	(669)	(517)
Proceeds from sales and maturities of debt and equity securities	4,495	695	563
Notes receivable from affiliated companies	173	(173)	313
Other	(103)	(67)	(65)
Net cash used in investing activities	(1,785)	(2,058)	(1,340)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	495	918	988
Payments for the redemption of long-term debt	(572)	(262)	(769)
Notes payable to affiliated companies	196	(108)	108
Distributions to parent			(75)
Other	(1)	13	1
Net cash provided by financing activities	118	561	253
Net (decrease) increase in cash, cash equivalents, and restricted cash	(6)	(19)	22
Cash, cash equivalents, and restricted cash at beginning of period	56	75	53
Cash, cash equivalents, and restricted cash at end of period	50	56	75
Cash and cash equivalents at beginning of period	17
Cash and cash equivalents at end of period	11	17
Supplemental Disclosures:
Cash paid for interest, net of amount capitalized	321	332	270
Cash received from income taxes	138	1	(120)
Significant non-cash transactions:
Accrued capital expenditures	214	272	258
Duke Energy Ohio
CASH FLOWS FROM OPERATING ACTIVITIES
Net (loss) income attributable to Duke Energy	252	238	176
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	283	269	271
Equity component of AFUDC	(7)	(13)	(11)
(Gains) Losses on sales of other assets	0	0	(106)
Deferred income taxes	31	81	25
Payments for asset retirement obligations	(2)	(8)	(3)
Provision for rate refunds	14	7	24
(Increase) decrease in
Receivables	(13)	20	(33)
Receivables from affiliated companies	9	22	19
Inventory	25	(9)	7
Other current assets	(18)	(5)	16
Increase (decrease) in
Accounts payable	2	(17)	(19)
Accounts payable to affiliated companies	0	(10)	16
Taxes accrued	30	17	12
Other current liabilities	3	1	14
Other assets	(32)	(26)	(24)
Other liabilities	(2)	(41)	(26)
Net cash provided by (used in) operating activities	575	526	570
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(834)	(952)	(827)
Notes receivable from affiliated companies	(19)		14
Other	(48)	(68)	(89)
Net cash used in investing activities	(901)	(1,020)	(902)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	467	1,003	99
Payments for the redemption of long-term debt		(551)	(3)
Notes payable to affiliated companies	(144)	38	245
Net cash provided by financing activities	323	490	341
Net increase (decrease) in cash and cash equivalents	(3)	(4)	9
Cash and cash equivalents at beginning of period	17	21	12
Cash and cash equivalents at end of period	14	17	21
Supplemental Disclosures:
Cash paid for interest, net of amount capitalized	97	97	87
Cash received from income taxes		(37)	(6)
Significant non-cash transactions:
Accrued capital expenditures	104	109	95
Transfer of ownership interest of certain equity method investees to parent			106
Duke Energy Indiana
CASH FLOWS FROM OPERATING ACTIVITIES
Net (loss) income attributable to Duke Energy	408	436	393
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	572	531	524
Equity component of AFUDC	(23)	(18)	(32)
Impairment charges			30
Deferred income taxes	29	156	95
Payments for asset retirement obligations	(63)	(48)	(69)
Provision for rate refunds			53
(Increase) decrease in
Receivables	8	(8)	7
Receivables from affiliated companies	0	41	3
Inventory	44	(95)	28
Other current assets	(3)	76	(25)
Increase (decrease) in
Accounts payable	(12)	(10)	37
Accounts payable to affiliated companies	1	4	5
Taxes accrued	13	(25)	(52)
Other current liabilities	6	15	14
Other assets	(68)	(74)	26
Other liabilities	26	16	(31)
Net cash provided by (used in) operating activities	938	997	1,006
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(888)	(876)	(832)
Purchases of debt and equity securities	(37)	(26)	(48)
Proceeds from sales and maturities of debt and equity securities	22	20	44
Notes receivable from affiliated companies	(33)
Other	48	(49)	18
Net cash used in investing activities	(888)	(931)	(818)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	544	485
Payments for the redemption of long-term debt	(513)	(213)	(3)
Notes payable to affiliated companies	101	(137)	6
Distributions to parent	(200)	(200)	(175)
Other			(1)
Net cash provided by financing activities	(68)	(65)	(173)
Net increase (decrease) in cash and cash equivalents	(18)	1	15
Cash and cash equivalents at beginning of period	25	24	9
Cash and cash equivalents at end of period	7	25	24
Supplemental Disclosures:
Cash paid for interest, net of amount capitalized	164	150	162
Cash received from income taxes	36	(6)	75
Significant non-cash transactions:
Accrued capital expenditures	101	102	88
Piedmont
CASH FLOWS FROM OPERATING ACTIVITIES
Net (loss) income attributable to Duke Energy	273	202	129
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	182	174	161
Equity in losses (earnings) of unconsolidated affiliates	(9)	(8)	(7)
Equity component of AFUDC	(19)
Impairment charges	7
Deferred income taxes	53	136	(31)
Provision for rate refunds	(33)	2	43
(Increase) decrease in
Receivables	10	28	7
Receivables from affiliated companies		12	(15)
Inventory	3	(2)	(4)
Other current assets	(66)	(25)	71
Increase (decrease) in
Accounts payable	16	(7)	15
Accounts payable to affiliated companies	76	(35)	25
Taxes accrued	3	(60)	65
Other current liabilities	(11)	1	21
Other assets	(11)	1	3
Other liabilities	7	(10)	(5)
Net cash provided by (used in) operating activities	481	409	478
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(901)	(1,053)	(721)
Contributions to equity method investments		(16)
Return of investment capital	2	4	3
Other	(28)	(14)	(10)
Net cash used in investing activities	(929)	(1,083)	(731)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	394	596	100
Payments for the redemption of long-term debt		(350)
Notes payable to affiliated companies	54	278	(166)
Contribution from parent		150	300
Net cash provided by financing activities	448	674	234
Net increase (decrease) in cash and cash equivalents			(19)
Cash and cash equivalents at beginning of period			19
Supplemental Disclosures:
Cash paid for interest, net of amount capitalized	115	84	79
Cash received from income taxes	(36)	(31)	(16)
Significant non-cash transactions:
Accrued capital expenditures	$ 106	$ 109	$ 96

Consolidated Statements of Equi

Consolidated Statements of Equity - USD ($) $ in Millions		Total		Preferred Stock	Common Stock	Additional Paid In Capital		Retained Earnings		Net Gains (Losses) on Cash Flow Hedges		Net Unrealized Gains (Losses) on Available-for-Sale Securities		Pension and OPEB Adjustments		Common Stockholders' Equity		Noncontrolling Interests		Duke Energy Carolinas		Duke Energy CarolinasMembers Equity		Duke Energy CarolinasNet Gains (Losses) on Cash Flow Hedges	Progress Energy		Progress EnergyAdditional Paid In Capital	Progress EnergyRetained Earnings		Progress EnergyNet Gains (Losses) on Cash Flow Hedges		Progress EnergyNet Unrealized Gains (Losses) on Available-for-Sale Securities		Progress EnergyPension and OPEB Adjustments		Progress EnergyCommon Stockholders' Equity		Progress EnergyNoncontrolling Interests		Duke Energy Progress	Duke Energy ProgressMembers Equity	Duke Energy Florida		Duke Energy FloridaMembers Equity		Duke Energy FloridaNet Unrealized Gains (Losses) on Available-for-Sale Securities		Duke Energy Ohio	Duke Energy OhioCommon Stock	Duke Energy OhioAdditional Paid In Capital	Duke Energy OhioRetained Earnings	Duke Energy Indiana	Duke Energy IndianaMembers Equity	Piedmont	PiedmontCommon Stock	PiedmontRetained Earnings	Common Stock	Common StockCommon Stock	Common StockAdditional Paid In Capital	Common StockCommon Stockholders' Equity	Series A Preferred Stock	[5]	Series A Preferred StockPreferred Stock	[5]	Series A Preferred StockCommon Stockholders' Equity	[5]	Series B Preferred Stock	[5]	Series B Preferred StockPreferred Stock	[5]	Series B Preferred StockCommon Stockholders' Equity	[5]
Beginning Balance (parent) at Dec. 31, 2017		$ 41,737			$ 1	$ 38,792		$ 3,013		$ (10)		$ 12		$ (69)		$ 41,739		$ (2)							$ 13,465		$ 9,143	$ 4,350		$ (18)		$ 5		$ (12)		$ 13,468		$ (3)
Beginning Members' Equity at Dec. 31, 2017																				$ 11,361		$ 11,368		$ (7)																	$ 7,949	$ 5,618		$ 5,614		$ 4							$ 4,121
Beginning Balance (Attributable to Parent) at Dec. 31, 2017																																																$ 3,163	$ 762	$ 2,670	$ (269)			$ 1,662	$ 860	$ 802
Balance (in shares) at Dec. 31, 2017																																																										700,000,000
Net income		2,644						2,666								2,666		(22)
Net (loss) income attributable to Duke Energy		2,666																		1,071		1,071			1,027															$ 667	667	554		554				176			176	$ 393	393	129		129
Net income		2,644																							1,033			1,027								1,027		6
Contribution from parent																																																106		106				300	300
Other comprehensive income (loss), net of tax		(13)	[1]							(4)		(3)		(6)		(13)				1				1	10					6		(1)		5		10						(1)				(1)
Stock issuances, shares																																																										27,000,000
Stock issuances																																																									$ 2,003		$ 2,003	$ 2,003
Distributions/Dividends to parent		(2,578)						(2,578)								(2,578)				(750)		(750)			(250)			(250)								(250)					(175)	(75)		(75)									(175)
Distributions to noncontrolling interest in subsidiaries		(1)																(1)							(1)													(1)
Other		42	[2]					12	[2]			(12)	[2]					42	[2]						0	[3]		4	[3]			(5)	[3]			(1)	[3]	1	[3]			(1)	[4]	4	[4]	(5)	[4]
Balance (in shares) at Dec. 31, 2018																																																										727,000,000
Ending Balance (parent) at Dec. 31, 2018		43,834			1	40,795		3,113		(14)		(3)		(75)		43,817		17							14,257		9,143	5,131		(12)		(1)		(7)		14,254		3
Ending member's equity at Dec. 31, 2018																				11,683		11,689		(6)																	8,441	6,095		6,097		(2)							4,339
Ending Balance (Attributable to Parent) at Dec. 31, 2018																																																3,445	762	2,776	(93)			2,091	1,160	931
Net income		3,530						3,707								3,707		(177)
Net (loss) income attributable to Duke Energy		3,748																		1,403		1,403			1,327															805	805	692		692				$ 238			238	436	436	202		202
Net income		3,571																							1,327			1,327								1,327
Contribution from parent																																																						$ 150	150
Other comprehensive income (loss), net of tax		(24)	[1]							(41)		8		9		(24)									8					5		1		2		8						1				1
Stock issuances, shares																																																										6,000,000
Stock issuances																																																									552		552	552	$ 973		$ 973		$ 973		$ 989		$ 989		$ 989
Distributions/Dividends to parent		(2,735)						(2,735)								(2,735)				(275)		(275)																															(200)
Sale of noncontrolling interest	[6]	407				(466)				10						(456)		863
Contribution from noncontrolling interest, net of transaction costs(f)	[7]	428																428
Distributions to noncontrolling interest in subsidiaries		(4)																(4)
Other		$ 1	[8]					23	[8]	(6)	[8]	(2)	[8]	(16)	[8]	(1)	[8]	2	[8]	0		1		(1)	$ 1	[9]		7	[9]	(3)	[9]	(1)	[9]	(2)	[9]	1	[9]
Balance (in shares) at Dec. 31, 2019		733,000,000																							100																							90,000,000						100				733,000,000
Ending Balance (parent) at Dec. 31, 2019		$ 47,951		$ 1,962	1	40,881		4,108		(51)		3		(82)		46,822		1,129							$ 15,593		9,143	6,465		(10)		(1)		(7)		15,590		3
Ending member's equity at Dec. 31, 2019																				12,811		12,818		(7)																9,246	9,246	6,788		6,789		(1)						4,575	4,575
Ending Balance (Attributable to Parent) at Dec. 31, 2019		46,822																							15,590																							$ 3,683	762	2,776	145			$ 2,443	1,310	1,133
Net income		975						1,270								1,270		(295)
Net (loss) income attributable to Duke Energy		1,377																		956		956			1,045															415	415	771		771				$ 252			252	408	408	273		273
Net income		1,082																							1,046			1,045								1,045		1
Other comprehensive income (loss), net of tax		(118)	[1]							(116)		3		6		(107)		(11)							3					5		(1)		(1)		3						(1)				(1)
Stock issuances, shares																																																										36,000,000
Stock issuances																																																									$ 2,902		$ 2,902	$ 2,902
Distributions/Dividends to parent		(2,815)						(2,815)								(2,815)				(600)		(600)			(400)			(400)								(400)					(400)												(200)
Contribution from noncontrolling interest, net of transaction costs(f)	[7]	409				(17)										(17)		426
Distributions to noncontrolling interest in subsidiaries		(30)																(30)
Other		$ (90)	[10]			1	[10]	(92)	[10]							(91)	[10]	1	[10]	(13)	[11]	(13)	[11]		$ (1)			(1)								(1)					(1)													$ (1)		(1)
Balance (in shares) at Dec. 31, 2020		769,000,000																							100																							90,000,000						100				769,000,000
Ending Balance (parent) at Dec. 31, 2020		$ 49,184		$ 1,962	$ 1	$ 43,767		$ 2,471		$ (167)		$ 6		$ (76)		$ 47,964		$ 1,220							$ 16,241		$ 9,143	$ 7,109		$ (5)		$ (2)		$ (8)		$ 16,237		$ 4
Ending member's equity at Dec. 31, 2020																				$ 13,154		$ 13,161		$ (7)																$ 9,260	$ 9,260	$ 7,558		$ 7,560		$ (2)						$ 4,783	$ 4,783
Ending Balance (Attributable to Parent) at Dec. 31, 2020		$ 47,964																							$ 16,237																							$ 3,935	$ 762	$ 2,776	$ 397			$ 2,715	$ 1,310	$ 1,405
[1]	Net of income tax impacts of approximately $35 million for the year ended December 31, 2020. Tax impacts are immaterial for other periods presented.
[2]	Amounts in Retained Earnings and AOCI represent a cumulative-effect adjustment due to implementation of a new accounting standard related to Financial Instruments Classification and Measurement. See Note 1 for more information. Amount in Noncontrolling Interests primarily relates to tax equity financing activity in the Commercial Renewables segment.
[3]	Amounts in Retained Earnings and AOCI represent a cumulative-effect adjustment due to implementation of a new accounting standard related to Financial Instruments Classification and Measurement. See Note 1 for more information.
[4]	Amounts represent a cumulative-effect adjustment due to implementation of a new accounting standard related to Financial Instruments Classification and Measurement. See Note 1 for more information.
[5]	Duke Energy issued 40 million depositary shares of preferred stock, Series A, in the first quarter of 2019 and 1 million shares of preferred stock, Series B, in the third quarter of 2019.
[6]	See Note 1 for additional discussion of the transaction.
[7]	Relates to tax equity financing activity in the Commercial Renewables segment.
[8]	Amounts in Retained Earnings and AOCI primarily represent impacts to accumulated other comprehensive income due to implementation of a new accounting standard related to Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.
[9]	Amounts in Retained Earnings and AOCI primarily represent impacts to accumulated other comprehensive income due to implementation of a new accounting standard related to Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.
[10]	Amounts in Retained earnings primarily represent impacts due to implementation of a new accounting standard related to Current Estimated Credit Losses. See Note 1 for additional discussion.
[11]	Amounts primarily represent impacts due to implementation of a new accounting standard related to Credit Losses. See Note 1 for additional discussion.

Consolidated Statements of Eq_2

Consolidated Statements of Equity (Parentheticals) - Preferred Stock - shares shares in Millions	3 Months Ended
	Sep. 30, 2019	Mar. 31, 2019
Series A Preferred Stock
Stock issuances, shares		40
Series B Preferred Stock
Stock issuances, shares	1

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Index to Combined Notes To Consolidated Financial Statements The notes to the consolidated financial statements are a combined presentation. The following table indicates the registrants to which the notes apply. Applicable Notes Registrant 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Duke Energy • • • • • • • • • • • • • • • • • • • • • • • • Duke Energy Carolinas • • • • • • • • • • • • • • • • • • • • • • Progress Energy • • • • • • • • • • • • • • • • • • • • • Duke Energy Progress • • • • • • • • • • • • • • • • • • • • • Duke Energy Florida • • • • • • • • • • • • • • • • • • • • • Duke Energy Ohio • • • • • • • • • • • • • • • • • • • • Duke Energy Indiana • • • • • • • • • • • • • • • • • • • • • • Piedmont • • • • • • • • • • • • • • • • • • • • Tables within the notes may not sum across due to (i) Progress Energy's consolidation of Duke Energy Progress, Duke Energy Florida and other subsidiaries that are not registrants and (ii) subsidiaries that are not registrants but included in the consolidated Duke Energy balances. Nature of Operations and Basis of Consolidation Duke Energy is an energy company headquartered in Charlotte, North Carolina, subject to regulation by the FERC and other regulatory agencies listed below. Duke Energy operates in the U.S. primarily through its direct and indirect subsidiaries. Certain Duke Energy subsidiaries are also subsidiary registrants, including Duke Energy Carolinas; Progress Energy; Duke Energy Progress; Duke Energy Florida; Duke Energy Ohio; Duke Energy Indiana and Piedmont. When discussing Duke Energy’s consolidated financial information, it necessarily includes the results of its separate Subsidiary Registrants, which along with Duke Energy, are collectively referred to as the Duke Energy Registrants. The information in these combined notes relates to each of the Duke Energy Registrants as noted in the Index to Combined Notes to Consolidated Financial Statements. However, none of the Subsidiary Registrants make any representation as to information related solely to Duke Energy or the Subsidiary Registrants of Duke Energy other than itself. These Consolidated Financial Statements include, after eliminating intercompany transactions and balances, the accounts of the Duke Energy Registrants and subsidiaries or VIEs where the respective Duke Energy Registrants have control. See Note 17 for additional information on VIEs. These Consolidated Financial Statements also reflect the Duke Energy Registrants’ proportionate share of certain jointly owned generation and transmission facilities. See Note 8 for additional information on joint ownership. Substantially all of the Subsidiary Registrants' operations qualify for regulatory accounting. Duke Energy Carolinas is a regulated public utility primarily engaged in the generation, transmission, distribution and sale of electricity in portions of North Carolina and South Carolina. Duke Energy Carolinas is subject to the regulatory provisions of the NCUC, PSCSC, NRC and FERC. Progress Energy is a public utility holding company, which conducts operations through its wholly owned subsidiaries, Duke Energy Progress and Duke Energy Florida. Progress Energy is subject to regulation by FERC and other regulatory agencies listed below. Duke Energy Progress is a regulated public utility primarily engaged in the generation, transmission, distribution and sale of electricity in portions of North Carolina and South Carolina. Duke Energy Progress is subject to the regulatory provisions of the NCUC, PSCSC, NRC and FERC. Duke Energy Florida is a regulated public utility primarily engaged in the generation, transmission, distribution and sale of electricity in portions of Florida. Duke Energy Florida is subject to the regulatory provisions of the FPSC, NRC and FERC. Duke Energy Ohio is a regulated public utility primarily engaged in the transmission and distribution of electricity in portions of Ohio and Kentucky, the generation and sale of electricity in portions of Kentucky and the transportation and sale of natural gas in portions of Ohio and Kentucky. Duke Energy Ohio conducts competitive auctions for retail electricity supply in Ohio whereby the energy price is recovered from retail customers and recorded in Operating Revenues on the Consolidated Statements of Operations and Comprehensive Income. Operations in Kentucky are conducted through its wholly owned subsidiary, Duke Energy Kentucky. References herein to Duke Energy Ohio collectively include Duke Energy Ohio and its subsidiaries, unless otherwise noted. Duke Energy Ohio is subject to the regulatory provisions of the PUCO, KPSC and FERC. Duke Energy Indiana is a regulated public utility primarily engaged in the generation, transmission, distribution and sale of electricity in portions of Indiana. Duke Energy Indiana is subject to the regulatory provisions of the IURC and FERC. Piedmont is a regulated public utility primarily engaged in the distribution of natural gas in portions of North Carolina, South Carolina and Tennessee. Piedmont is subject to the regulatory provisions of the NCUC, PSCSC, TPUC and FERC. Certain prior year amounts have been reclassified to conform to the current year presentation. COVID-19 The COVID-19 pandemic is having a significant impact on global health and economic environments. In March 2020, the World Health Organization declared COVID-19 a global pandemic, and the federal government proclaimed that the COVID-19 outbreak in the United States constitutes a national emergency. The Duke Energy Registrants are monitoring developments closely and responding appropriately. The company incurred approximately $112 million of incremental COVID-19 costs before deferral for the year ended December 31, 2020, included in Operation, maintenance and other on the Consolidated Statements of Operations. Further, the company waived approximately $64 million of late payment fees for the year ended December 31, 2020. The company has deferred approximately $76 million of the incremental costs, which were primarily bad debt expense, personal protective equipment and cleaning supplies, and a cost component of late payment fees. See Notes 3, 6, 17, 18 and 23 for additional information as well as steps taken to mitigate the impacts to our business and customers from the COVID-19 pandemic. Other Current Assets and Liabilities The following table provides a description of amounts included in Other within Current Assets or Current Liabilities that exceed 5% of total Current Assets or Current Liabilities on the Duke Energy Registrants' Consolidated Balance Sheets at either December 31, 2020, or 2019. December 31, (in millions) Location 2020 2019 Duke Energy Other accrued liabilities Current Liabilities $ 1,455 $ 604 Accrued compensation Current Liabilities 662 862 Duke Energy Carolinas Accrued compensation Current Liabilities $ 213 $ 271 Other accrued liabilities Current Liabilities 178 147 Progress Energy Customer deposits Current Liabilities $ 347 $ 354 Duke Energy Florida Customer deposits Current Liabilities $ 203 $ 209 Duke Energy Ohio Gas Storage Current Assets $ 21 $ — Duke Energy Indiana Income taxes receivable Current Assets $ 9 $ 44 Discontinued Operations Duke Energy has elected to present cash flows of discontinued operations combined with cash flows of continuing operations. Unless otherwise noted, the notes to these consolidated financial statements exclude amounts related to discontinued operations for all periods presented. For the years ended December 31, 2020, 2019 and 2018, the Income (Loss) From Discontinued Operations, net of tax on Duke Energy's Consolidated Statements of Operations is entirely attributable to controlling interest. Noncontrolling Interest Duke Energy maintains a controlling financial interest in certain less than wholly owned nonregulated subsidiaries. As a result, Duke Energy consolidates these subsidiaries and presents the third-party investors' portion of Duke Energy's net income (loss), net assets and comprehensive income (loss) as noncontrolling interest. Noncontrolling interest is included as a component of equity on the Consolidated Balance Sheet. Several operating agreements of Duke Energy's subsidiaries with noncontrolling interest are subject to allocations of tax attributes and cash flows in accordance with contractual agreements that vary throughout the lives of the subsidiaries. Therefore, Duke Energy and the other investors' (the owners) interests in the subsidiaries are not fixed, and the subsidiaries apply the HLBV method in allocating income or loss and other comprehensive income or loss (all measured on a pretax basis) to the owners. The HLBV method measures the amounts that each owner would hypothetically claim at each balance sheet reporting date, including tax benefits realized by the owners, most of which is over the IRS recapture period, upon a hypothetical liquidation of the subsidiary at the net book value of its underlying assets. The change in the amount that each owner would hypothetically receive at the reporting date compared to the amount it would have received on the previous reporting date represents the amount of income or loss allocated to each owner for the reporting period. Other operating agreements of Duke Energy's subsidiaries with noncontrolling interest allocate profit and loss based on their pro rata shares of the ownership interest in the respective subsidiary. Therefore, Duke Energy allocates net income or loss and other comprehensive income or loss of these subsidiaries to the owners based on their pro rata shares. During the third quarter of 2019, Duke Energy completed a sale of minority interest in a portion of certain renewable assets within the Commercial Renewables Segment for pretax proceeds to Duke Energy of $415 million. The portion of Duke Energy's commercial renewables energy portfolio sold includes 49% of 37 operating wind, solar and battery storage assets and 33% of 11 operating solar assets across the U.S. Duke Energy retained control of these assets, and, therefore, no gain or loss was recognized on the Consolidated Statements of Operations. The difference between the consideration received and the carrying value of the noncontrolling interest claim on net assets is $466 million, net of tax benefit of $8 million, and was recorded to equity. The following table presents cash received for the sale of noncontrolling interest and allocated losses to noncontrolling interest for the years ended December 31, 2020, and 2019. December 31, (in millions) 2020 2019 Noncontrolling Interest Capital Contributions Cash received for the sale of noncontrolling interest to tax equity members $ 426 $ 428 Cash received for the sale of noncontrolling interest to pro rata share members — 415 Total Noncontrolling Interest Capital Contributions $ 426 $ 843 Noncontrolling Interest Allocation of Income Allocated losses to noncontrolling tax equity members utilizing the HLBV method $ 271 $ 165 Allocated losses to noncontrolling members based on pro rata shares of ownership 24 12 Total Noncontrolling Interest Allocated Losses $ 295 $ 177 2021 Sale of Minority Interest in Duke Energy Indiana In January 2021, Duke Energy entered into a definitive agreement providing for the sale of a 19.9% minority interest in Duke Energy Indiana with an affiliate of GIC, Singapore's sovereign wealth fund and an experienced investor in U.S. infrastructure. To facilitate the transaction, Duke Energy will issue and sell membership interests in Duke Energy Indiana Holdco, LLC. a newly created holding company that will own 100% of the issued and outstanding membership interests in Duke Energy Indiana. The transaction will be completed following two closings for an aggregate purchase price of approximately $2 billion. The first closing is expected to be completed in the second quarter of 2021 and Duke Energy will issue and sell 11.1% of the membership interests in exchange for 50% of the purchase price. Under the terms of the agreement, Duke Energy has the discretion to determine the timing of the second closing, but it will occur no later than January 2023. At the second closing, Duke Energy will issue and sell additional membership interests such that GIC will own 19.9% of the membership interests for the remaining 50% of the purchase price. Duke Energy will continue to operate and retain control of Duke Energy Indiana and, therefore, no gain or loss is expected to be recognized in the Consolidated Statements of Operations. Additionally, the transaction will be reflected within Duke Energy Corporations' stockholders' equity as a sale of a noncontrolling interest. Acquisitions The Duke Energy Registrants consolidate assets and liabilities from acquisitions as of the purchase date and include earnings from acquisitions in consolidated earnings after the purchase date. Significant Accounting Policies Use of Estimates In preparing financial statements that conform to GAAP, the Duke Energy Registrants must make estimates and assumptions that affect the reported amounts of assets and liabilities, the reported amounts of revenues and expenses and the disclosure of contingent assets and liabilities at the date of the financial statements. Actual results could differ from those estimates. Regulatory Accounting The majority of the Duke Energy Registrants’ operations are subject to price regulation for the sale of electricity and natural gas by state utility commissions or FERC. When prices are set on the basis of specific costs of the regulated operations and an effective franchise is in place such that sufficient natural gas or electric services can be sold to recover those costs, the Duke Energy Registrants apply regulatory accounting. Regulatory accounting changes the timing of the recognition of costs or revenues relative to a company that does not apply regulatory accounting. As a result, regulatory assets and regulatory liabilities are recognized on the Consolidated Balance Sheets. Regulatory assets and liabilities are amortized consistent with the treatment of the related cost in the ratemaking process. Regulatory assets are reviewed for recoverability each reporting period. If a regulatory asset is no longer deemed probable of recovery, the deferred cost is charged to earnings. See Note 3 for further information. Regulatory accounting rules also require recognition of a disallowance (also called "impairment") loss if it becomes probable that part of the cost of a plant under construction (or a recently completed plant or an abandoned plant) will be disallowed for ratemaking purposes and a reasonable estimate of the amount of the disallowance can be made. For example, if a cost cap is set for a plant still under construction, the amount of the disallowance is a result of a judgment as to the ultimate cost of the plant. These disallowances can require judgments on allowed future rate recovery. When it becomes probable that regulated generation, transmission or distribution assets will be abandoned, the cost of the asset is removed from plant in service. The value that may be retained as a regulatory asset on the balance sheet for the abandoned property is dependent upon amounts that may be recovered through regulated rates, including any return. As such, an impairment charge could be partially or fully offset by the establishment of a regulatory asset if rate recovery is probable. The impairment charge for a disallowance of costs for regulated plants under construction, recently completed or abandoned is based on discounted cash flows. The Duke Energy Registrants utilize cost-tracking mechanisms, commonly referred to as fuel adjustment clauses or PGA clauses. These clauses allow for the recovery of fuel and fuel-related costs, portions of purchased power, natural gas costs and hedging costs through surcharges on customer rates. The difference between the costs incurred and the surcharge revenues is recorded either as an adjustment to Operating Revenues, Operating Expenses – Fuel used in electric generation or Operating Expenses – Cost of natural gas on the Consolidated Statements of Operations, with an off-setting impact on regulatory assets or liabilities. Cash, Cash Equivalents and Restricted Cash All highly liquid investments with maturities of three months or less at the date of acquisition are considered cash equivalents. Duke Energy, Progress Energy and Duke Energy Florida have restricted cash balances related primarily to collateral assets, escrow deposits and VIEs. See Note 17 for additional information. Restricted cash amounts are included in Other within Current Assets and Other Noncurrent Assets on the Consolidated Balance Sheets. The following table presents the components of cash, cash equivalents and restricted cash included in the Consolidated Balance Sheets. December 31, 2020 December 31, 2019 Duke Duke Duke Progress Energy Duke Progress Energy Energy Energy Florida Energy Energy Florida Current Assets Cash and cash equivalents $ 259 $ 59 $ 11 $ 311 $ 48 $ 17 Other 194 39 39 222 39 39 Other Noncurrent Assets Other 103 102 — 40 39 — Total cash, cash equivalents and restricted cash $ 556 $ 200 $ 50 $ 573 $ 126 $ 56 Inventory Inventory related to regulated operations is valued at historical cost. Inventory related to nonregulated operations is valued at the lower of cost or market. Inventory is charged to expense or capitalized to property, plant and equipment when issued, primarily using the average cost method. Excess or obsolete inventory is written down to the lower of cost or net realizable value. Once inventory has been written down, it creates a new cost basis for the inventory that is not subsequently written up. Provisions for inventory write-offs were not material at December 31, 2020, and 2019, respectively. The components of inventory are presented in the tables below. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Materials and supplies $ 2,312 $ 785 $ 999 $ 673 $ 325 $ 78 $ 307 $ 12 Coal 561 186 193 131 63 16 165 — Natural gas, oil and other 294 39 183 107 76 16 1 56 Total inventory $ 3,167 $ 1,010 $ 1,375 $ 911 $ 464 $ 110 $ 473 $ 68 December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Materials and supplies $ 2,297 $ 768 $ 1,038 $ 686 $ 351 $ 79 $ 318 $ 5 Coal 586 187 186 138 48 15 198 — Natural gas, oil and other 349 41 199 110 90 41 1 67 Total inventory $ 3,232 $ 996 $ 1,423 $ 934 $ 489 $ 135 $ 517 $ 72 Investments in Debt and Equity Securities The Duke Energy Registrants classify investments in equity securities as FV-NI and investments in debt securities as AFS. Both categories are recorded at fair value on the Consolidated Balance Sheets. Realized and unrealized gains and losses on securities classified as FV-NI are reported through net income. Unrealized gains and losses for debt securities classified as AFS are included in AOCI until realized, unless it is determined the carrying value of an investment has a credit loss. For certain investments of regulated operations, such as substantially all of the NDTF, realized and unrealized gains and losses (including any credit losses) on debt securities are recorded as a regulatory asset or liability. The credit loss portion of debt securities of nonregulated operations are included in earnings. Investments in debt and equity securities are classified as either current or noncurrent based on management’s intent and ability to sell these securities, taking into consideration current market liquidity. See Note 15 for further information. Goodwill Duke Energy, Progress Energy, Duke Energy Ohio and Piedmont perform annual goodwill impairment tests as of August 31 each year at the reporting unit level, which is determined to be a business segment or one level below. Duke Energy, Progress Energy, Duke Energy Ohio and Piedmont update these tests between annual tests if events or circumstances occur that would more likely than not reduce the fair value of a reporting unit below its carrying value. See Note 11 for further information. Intangible Assets Intangible assets are included in Other in Other Noncurrent Assets on the Consolidated Balance Sheets. Generally, intangible assets are amortized using an amortization method that reflects the pattern in which the economic benefits of the intangible asset are consumed or on a straight-line basis if that pattern is not readily determinable. Amortization of intangibles is reflected in Depreciation and amortization on the Consolidated Statements of Operations. Intangible assets are subject to impairment testing and if impaired, the carrying value is accordingly reduced. RECs are used to measure compliance with renewable energy standards and are held primarily for consumption. See Note 11 for further information. Long-Lived Asset Impairments The Duke Energy Registrants evaluate long-lived assets, excluding goodwill, for impairment when circumstances indicate the carrying value of those assets may not be recoverable. An impairment exists when a long-lived asset’s carrying value exceeds the estimated undiscounted cash flows expected to result from the use and eventual disposition of the asset. The estimated cash flows may be based on alternative expected outcomes that are probability weighted. If the carrying value of the long-lived asset is not recoverable based on these estimated future undiscounted cash flows, the carrying value of the asset is written down to its then current estimated fair value and an impairment charge is recognized. The Duke Energy Registrants assess fair value of long-lived assets using various methods, including recent comparable third-party sales, internally developed discounted cash flow analysis and analysis from outside advisors. Triggering events to reassess cash flows may include, but are not limited to, significant changes in commodity prices, the condition of an asset or management’s interest in selling the asset. Equity Method Investment Impairments Investments in affiliates that are not controlled by Duke Energy, but over which it has significant influence, are accounted for using the equity method. Equity method investments are assessed for impairment whenever events or changes in circumstances indicate that the carrying amount of the investment may not be recoverable. If the decline in value is considered to be other than temporary, the investment is written down to its estimated fair value, which establishes a new cost basis in the investment. Impairment assessments use a discounted cash flow income approach and include consideration of the severity and duration of any decline in the fair value of the investments. The estimated cash flows may be based on alternative expected outcomes that are probability weighted. Key inputs that involve estimates and significant management judgment include cash flow projections, selection of a discount rate, probability weighting of potential outcomes, and whether any decline in value is considered temporary. Property, Plant and Equipment Property, plant and equipment are stated at the lower of depreciated historical cost net of any disallowances or fair value, if impaired. The Duke Energy Registrants capitalize all construction-related direct labor and material costs, as well as indirect construction costs such as general engineering, taxes and financing costs. See “Allowance for Funds Used During Construction and Interest Capitalized” for information on capitalized financing costs. Costs of renewals and betterments that extend the useful life of property, plant and equipment are also capitalized. The cost of repairs, replacements and major maintenance projects, which do not extend the useful life or increase the expected output of the asset, are expensed as incurred. Depreciation is generally computed over the estimated useful life of the asset using the composite straight-line method. Depreciation studies are conducted periodically to update composite rates and are approved by state utility commissions and/or the FERC when required. The composite weighted average depreciation rates, excluding nuclear fuel, are included in the table that follows. Years Ended December 31, 2020 2019 2018 Duke Energy 3.0 % 3.1 % 3.0 % Duke Energy Carolinas 2.8 % 2.8 % 2.8 % Progress Energy 3.2 % 3.1 % 2.9 % Duke Energy Progress 3.1 % 3.1 % 2.9 % Duke Energy Florida 3.3 % 3.1 % 3.0 % Duke Energy Ohio 2.9 % 2.6 % 2.8 % Duke Energy Indiana 3.5 % 3.3 % 3.3 % Piedmont 2.3 % 2.4 % 2.5 % In general, when the Duke Energy Registrants retire regulated property, plant and equipment, the original cost plus the cost of retirement, less salvage value and any depreciation already recognized, is charged to accumulated depreciation. However, when it becomes probable the asset will be retired substantially in advance of its original expected useful life or is abandoned, the cost of the asset and the corresponding accumulated depreciation is recognized as a separate asset. If the asset is still in operation, the net amount is classified as Generation facilities to be retired, net on the Consolidated Balance Sheets. If the asset is no longer operating, the net amount is classified in Regulatory assets on the Consolidated Balance Sheets if deemed recoverable (see discussion of long-lived asset impairments above). The carrying value of the asset is based on historical cost if the Duke Energy Registrants are allowed to recover the remaining net book value and a return equal to at least the incremental borrowing rate. If not, an impairment is recognized to the extent the net book value of the asset exceeds the present value of future revenues discounted at the incremental borrowing rate. When the Duke Energy Registrants sell entire regulated operating units, or retire or sell nonregulated properties, the original cost and accumulated depreciation and amortization balances are removed from Property, Plant and Equipment on the Consolidated Balance Sheets. Any gain or loss is recorded in earnings, unless otherwise required by the applicable regulatory body. See Note 10 for additional information. Leases Duke Energy determines if an arrangement is a lease at contract inception based on whether the arrangement involves the use of a physically distinct identified asset and whether Duke Energy has the right to obtain substantially all of the economic benefits from the use of the asset throughout the period as well as the right to direct the use of the asset. As a policy election, Duke Energy does not evaluate arrangements with initial contract terms of less than one year as leases. Operating leases are included in Operating lease ROU assets, net, Other current liabilities and Operating lease liabilities on the Consolidated Balance Sheets. Finance leases are included in Property, plant and equipment, Current maturities of long-term debt and Long-Term Debt on the Consolidated Balance Sheets. For lessee and lessor arrangements, Duke Energy has elected a policy to not separate lease and non-lease components for all asset classes. For lessor arrangements, lease and non-lease components are only combined under one arrangement and accounted for under the lease accounting framework if the non-lease components are not the predominant component of the arrangement and the lease component would be classified as an operating lease. Nuclear Fuel Nuclear fuel is classified as Property, Plant and Equipment on the Consolidated Balance Sheets. Nuclear fuel in the front-end fuel processing phase is considered work in progress and not amortized until placed in service. Amortization of nuclear fuel is included within Fuel used in electric generation and purchased power on the Consolidated Statements of Operations. Amortization is recorded using the units-of-production method. Allowance for Funds Used During Construction and Interest Capitalized For regulated operations, the debt and equity costs of financing the construction of property, plant and equipment are reflected as AFUDC and capitalized as a component of the cost of property, plant and equipment. AFUDC equity is reported on the Consolidated Statements of Operations as non-cash income in Other income and expenses, net. AFUDC debt is reported as a non-cash offset to Interest Expense. After construction is completed, the Duke Energy Registrants are permitted to recover these costs through their inclusion in rate base and the corresponding subsequent depreciation or amortization of those regulated assets. AFUDC equity, a permanent difference for income taxes, reduces the ETR when capitalized and increases the ETR when depreciated or amortized. See Note 23 for additional information. For nonregulated operations, interest is capitalized during the construction phase with an offsetting non-cash credit to Interest Expense on the Consolidated Statements of Operations. Asset Retirement Obligations AROs are recognized for legal obligations associated with the retirement of property, plant and equipment. Substantially all AROs are related to regulated operations. When recording an ARO, the present value of the projected liability is recognized in the period in which it is incurred, if a reasonable estimate of fair value can be made. The liability is accreted over time. For operating plants, the present value of the liability is added to the cost of the associated asset and depreciated over the remaining life of the asset. For retired plants, the present value of the liability is recorded as a regulatory asset unless determined not to be probable of recovery. The present value of the initial obligation and subsequent updates are based on discounted cash flows, which include estimates regarding timing of future cash flows, selection of discount rates and cost escalation rates, among other factors. These estimates are subject to change. Depreciation expense is adjusted prospectively for any changes to the carrying amount of the associated asset. The Duke Energy Registrants receive amounts to fund the cost of the ARO for regulated operations through a combination of regulated revenues and earnings on the NDTF. As a result, amounts recovered in regulated revenues, earnings on the NDTF, accretion expense and depreciation of the associated asset are netted and deferred as a regulatory asset or liability. Accounts Payable During 2020, Duke Energy established a supply chain finance program (the “program”) with a global financial institution. The program is voluntary and allows Duke Energy suppliers, at their sole discretion, to sell their receivables from Duke Energy to the financial institution at a rate that leverages Duke Energy’s credit rating and, which may result in favorable terms compared to the rate available to the supplier on their own credit rating. Suppliers participating in the program, determine at their sole discretion which invoices they will sell to the financial institution. Suppliers’ decisions on which invoices are sold do not impact Duke Energy’s payment terms, which are based on commercial terms negotiated between Duke Energy and the supplier regardless of program participation. The commercial terms negotiated between Duke Energy and its suppliers are consistent regardless of whether the supplier elects to participate in the program. Duke Energy does not issue any guarantees with respect to the program and does not participate in negotiations between suppliers and the financial institution. Duke Energy does not have an economic interest in the supplier’s decision to participate in the program and receives no interest, fees or other benefit from the financial institution based on supplier participation in the program. At December 31, 2020, $15 million, $1 million and $14 million of the outstanding Accounts payable balance for Duke Energy, Duke Energy Ohio and Piedmont, respectively, was sold to the financial institution by our suppliers. Suppliers invoices sold to the financial institution under the program totaled $45 million, $9 million and $36 million for the year ended December 31, 2020, for Duke Energy, Duke Energy Ohio and Piedmont, respectively. All activity related to amounts due to suppliers who elected to participate in the program are included within Net cash provided by operating activities on the Consolidated Statements of Cash Flows. Revenue Recognition Duke Energy recognizes revenue as customers obtain control of promised goods and services in an amount that reflects consideration expected in exchange for those g

Business Segments

Business Segments	12 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Business Segments	BUSINESS SEGMENTS Reportable segments are determined based on information used by the chief operating decision-maker in deciding how to allocate resources and evaluate the performance of the business. Duke Energy evaluates segment performance based on segment income. Segment income is defined as income from continuing operations net of income attributable to noncontrolling interests and preferred stock dividends. Segment income, as discussed below, includes intercompany revenues and expenses that are eliminated on the Consolidated Financial Statements. Certain governance costs are allocated to each segment. In addition, direct interest expense and income taxes are included in segment income. Products and services are sold between affiliate companies and reportable segments of Duke Energy at cost. Segment assets as presented in the tables that follow exclude all intercompany assets. Duke Energy Duke Energy's segment structure includes the following segments: Electric Utilities and Infrastructure, Gas Utilities and Infrastructure and Commercial Renewables. The Electric Utilities and Infrastructure segment includes Duke Energy's regulated electric utilities in the Carolinas, Florida and the Midwest. The regulated electric utilities conduct operations through the Subsidiary Registrants that are substantially all regulated and, accordingly, qualify for regulatory accounting treatment. Electric Utilities and Infrastructure also includes Duke Energy's electric transmission infrastructure investments. The Gas Utilities and Infrastructure segment includes Piedmont, Duke Energy's natural gas local distribution companies in Ohio and Kentucky, and Duke Energy's natural gas storage and midstream pipeline investments. Gas Utilities and Infrastructure's operations are substantially all regulated and, accordingly, qualify for regulatory accounting treatment. The Commercial Renewables segment is primarily comprised of nonregulated utility-scale wind and solar generation assets located throughout the U.S. The remainder of Duke Energy’s operations is presented as Other, which is primarily comprised of interest expense on holding company debt, unallocated corporate costs and Duke Energy’s wholly owned captive insurance company, Bison. Other also includes Duke Energy's interest in NMC. See Note 12 for additional information on the investment in NMC. Business segment information is presented in the following tables. Segment assets presented exclude intercompany assets. Year Ended December 31, 2020 Electric Gas Total Utilities and Utilities and Commercial Reportable (in millions) Infrastructure Infrastructure Renewables Segments Other Eliminations Total Unaffiliated Revenues $ 21,687 $ 1,653 $ 502 $ 23,842 $ 26 $ — $ 23,868 Intersegment Revenues 33 95 — 128 71 (199) — Total Revenues $ 21,720 $ 1,748 $ 502 $ 23,970 $ 97 $ (199) $ 23,868 Interest Expense $ 1,320 $ 135 $ 66 $ 1,521 $ 657 $ (16) $ 2,162 Depreciation and amortization 4,068 258 199 4,525 209 (29) 4,705 Equity in earnings (losses) of unconsolidated affiliates (1) (2,017) — (2,018) 13 — (2,005) Income tax expense (benefit) 340 (349) (65) (74) (162) — (236) Segment income (loss) (a)(b)(c) 2,669 (1,266) 286 1,689 (426) — 1,263 Less noncontrolling interest 295 Add back preferred stock dividend 107 Income from discontinued operations, net of tax 7 Net income $ 1,082 Capital investments expenditures and acquisitions $ 7,629 $ 1,309 $ 1,219 $ 10,157 $ 264 $ — $ 10,421 Segment assets 138,225 13,849 6,716 158,790 3,598 — 162,388 (a) Electric Utilities and Infrastructure includes $948 million of Impairment charges and a reversal of $152 million included in Regulated electric operating revenue related to the CCR Settlement Agreement filed with the NCUC. Additionally, Electric Utilities and Infrastructure includes $19 million of Impairment charges related to the Clemson University Combined Heat and Power Plant, $5 million of Impairment charges related to the gas pipeline assets and $16 million of shareholder contributions within Operations, maintenance and other related to Duke Energy Carolinas' and Duke Energy Progress' 2019 North Carolina rate cases. See Note 3 for additional information. (b) Gas Utilities and Infrastructure includes $2.1 billion recorded within Equity in (losses) earnings of unconsolidated affiliates and $7 million of Impairment charges related to gas pipeline investments. See Notes 3 and 12 for additional information. (c) Other includes a $98 million reversal of 2018 severance costs due to a partial settlement in the Duke Energy Carolinas' 2019 North Carolina rate case. See Note 3 and 20 for additional information. Year Ended December 31, 2019 Electric Gas Total Utilities and Utilities and Commercial Reportable (in millions) Infrastructure Infrastructure Renewables Segments Other Eliminations Total Unaffiliated Revenues $ 22,798 $ 1,770 $ 487 $ 25,055 $ 24 $ — $ 25,079 Intersegment Revenues 33 96 — 129 71 (200) — Total Revenues $ 22,831 $ 1,866 $ 487 $ 25,184 $ 95 $ (200) $ 25,079 Interest Expense $ 1,345 $ 117 $ 95 $ 1,557 $ 705 $ (58) $ 2,204 Depreciation and amortization 3,951 256 168 4,375 178 (5) 4,548 Equity in earnings (losses) of unconsolidated affiliates 9 114 (4) 119 43 — 162 Income tax expense (benefit) 785 22 (115) 692 (173) — 519 Segment income (loss) (a)(b) 3,536 432 198 4,166 (452) — 3,714 Less noncontrolling interest 177 Add back preferred stock dividend 41 Loss from discontinued operations, net of tax (7) Net income $ 3,571 Capital investments expenditures and acquisitions $ 8,263 $ 1,539 $ 1,423 $ 11,225 $ 221 $ — $ 11,446 Segment assets 135,561 13,921 6,020 155,502 3,148 188 158,838 (a) Electric Utilities and Infrastructure includes a $27 million reduction of a prior year impairment at Citrus County CC related to the plant's cost cap. See Note 3 for additional information. (b) Gas Utilities and Infrastructure includes an after-tax impairment charge of $19 million for the remaining investment in Constitution. See Note 12 for additional information. Year Ended December 31, 2018 Electric Gas Total Utilities and Utilities and Commercial Reportable (in millions) Infrastructure Infrastructure Renewables Segments Other Eliminations Total Unaffiliated Revenues $ 22,242 $ 1,783 $ 477 $ 24,502 $ 19 $ — $ 24,521 Intersegment Revenues 31 98 — 129 70 (199) — Total Revenues $ 22,273 $ 1,881 $ 477 $ 24,631 $ 89 $ (199) $ 24,521 Interest Expense $ 1,288 $ 106 $ 88 $ 1,482 $ 657 $ (45) $ 2,094 Depreciation and amortization 3,523 245 155 3,923 152 (1) 4,074 Equity in earnings (losses) of unconsolidated affiliates 5 27 (1) 31 52 — 83 Income tax expense (benefit) (a) 799 78 (147) 730 (282) — 448 Segment income (loss) (b)(c)(d)(e) 3,058 274 9 3,341 (694) — 2,647 Less noncontrolling interest 22 Income from discontinued operations, net of tax 19 Net income $ 2,644 Capital investments expenditures and acquisitions $ 8,086 $ 1,133 $ 193 $ 9,412 $ 256 $ — $ 9,668 Segment assets 125,364 12,361 4,204 141,929 3,275 188 145,392 (a) All segments include adjustments to the December 31, 2017, estimate of the income tax effects of the Tax Act. Electric Utilities and Infrastructure includes a $24 million expense, Gas Utilities and Infrastructure includes a $1 million expense, Commercial Renewables includes a $3 million benefit and Other includes a $2 million benefit. See Note 23 for additional information. (b) Electric Utilities and Infrastructure includes after-tax regulatory and legislative impairment charges of $202 million related to rate case orders, settlements or other actions of regulators or legislative bodies and an after-tax impairment charge of $46 million related to the Citrus County CC at Duke Energy Florida. See Note 3 for additional information. (c) Gas Utilities and Infrastructure includes an after-tax impairment charge of $42 million for the investment in Constitution. See Note 12 for additional information. (d) Commercial Renewables includes an impairment charge of $91 million, net of $2 million Noncontrolling interests, related to goodwill. See Note 11 for additional information. (e) Other includes $65 million of after-tax costs to achieve the Piedmont merger, $144 million of after-tax severance charges related to a companywide initiative and an $82 million after-tax loss on the sale of Beckjord described below. For additional information, see Note 1 for the Piedmont merger and Note 20 for severance charges. In February 2018, Duke Energy sold Beckjord, a nonregulated facility retired during 2014, and recorded a pretax loss of $106 million within Gains (Losses) on Sales of Other Assets and Other, net and $1 million within Operation, maintenance and other on Duke Energy's Consolidated Statements of Operations for the year ended December 31, 2018. The sale included the transfer of coal ash basins and other real property and indemnification from any and all potential future claims related to the property, whether arising under environmental laws or otherwise. Geographical Information Substantially all assets and revenues from continuing operations are within the U.S. Major Customers For the year ended December 31, 2020, revenues from one customer of Duke Energy Progress are $553 million. Duke Energy Progress has one reportable segment, Electric Utilities and Infrastructure. No other Subsidiary Registrant has an individual customer representing more than 10% of its revenues. Products and Services The following table summarizes revenues of the reportable segments by type. Retail Wholesale Retail Total (in millions) Electric Electric Natural Gas Other Revenues 2020 Electric Utilities and Infrastructure $ 18,898 $ 1,878 $ — $ 944 $ 21,720 Gas Utilities and Infrastructure — — 1,691 57 1,748 Commercial Renewables — 434 — 68 502 Total Reportable Segments $ 18,898 $ 2,312 $ 1,691 $ 1,069 $ 23,970 2019 Electric Utilities and Infrastructure $ 19,745 $ 2,231 $ — $ 855 $ 22,831 Gas Utilities and Infrastructure — — 1,782 84 1,866 Commercial Renewables — 389 — 98 487 Total Reportable Segments $ 19,745 $ 2,620 $ 1,782 $ 1,037 $ 25,184 2018 Electric Utilities and Infrastructure $ 19,013 $ 2,345 $ — $ 915 $ 22,273 Gas Utilities and Infrastructure — — 1,817 64 1,881 Commercial Renewables — 375 — 102 477 Total Reportable Segments $ 19,013 $ 2,720 $ 1,817 $ 1,081 $ 24,631 Duke Energy Ohio Duke Energy Ohio has two reportable segments, Electric Utilities and Infrastructure and Gas Utilities and Infrastructure. Electric Utilities and Infrastructure transmits and distributes electricity in portions of Ohio and generates, distributes and sells electricity in portions of Northern Kentucky. Gas Utilities and Infrastructure transports and sells natural gas in portions of Ohio and Northern Kentucky. Both reportable segments conduct operations primarily through Duke Energy Ohio and its wholly owned subsidiary, Duke Energy Kentucky. The remainder of Duke Energy Ohio's operations is presented as Other. All Duke Energy Ohio assets and revenues from continuing operations are within the U.S. Year Ended December 31, 2020 Electric Gas Total Utilities and Utilities and Reportable (in millions) Infrastructure Infrastructure Segments Other Eliminations Total Total revenues $ 1,405 $ 453 $ 1,858 $ — $ — $ 1,858 Interest expense $ 85 $ 17 $ 102 $ — $ — $ 102 Depreciation and amortization 200 78 278 — — 278 Income tax expense (benefit) 19 26 45 (2) — 43 Segment income (loss)/Net income 162 96 258 (6) — 252 Capital expenditures $ 548 $ 286 $ 834 $ — $ — $ 834 Segment assets 6,615 3,380 9,995 32 (2) 10,025 Year Ended December 31, 2019 Electric Gas Total Utilities and Utilities and Reportable (in millions) Infrastructure Infrastructure Segments Other Eliminations Total Total revenues $ 1,456 $ 484 $ 1,940 $ — $ — $ 1,940 Interest expense $ 80 $ 29 $ 109 $ — $ — $ 109 Depreciation and amortization 182 83 265 — — 265 Income tax expense (benefit) 20 21 41 (1) — 40 Segment income (loss) 159 85 244 (5) — 239 Loss from discontinued operations, net of tax (1) Net income $ 238 Capital expenditures $ 680 $ 272 $ 952 $ — $ — $ 952 Segment assets 6,188 3,116 9,304 34 — 9,338 Year Ended December 31, 2018 Electric Gas Total Utilities and Utilities and Reportable (in millions) Infrastructure Infrastructure Segments Other Eliminations Total Total revenues $ 1,450 $ 506 $ 1,956 $ 1 $ — $ 1,957 Interest expense $ 67 $ 24 $ 91 $ 1 $ — $ 92 Depreciation and amortization 183 85 268 — — 268 Income tax expense (benefit) 47 24 71 (28) — 43 Segment income (loss)/Net Income (a) 186 93 279 (103) — 176 Capital expenditures $ 655 $ 172 $ 827 $ — $ — $ 827 Segment assets 5,643 2,874 8,517 38 — 8,555 (a) Other includes the loss on the sale of Beckjord, see discussion above.

Regulatory Matters

Regulatory Matters	12 Months Ended
	Dec. 31, 2020
Regulated Operations [Abstract]
Regulatory Matters	REGULATORY MATTERS REGULATORY ASSETS AND LIABILITIES The Duke Energy Registrants record regulatory assets and liabilities that result from the ratemaking process. See Note 1 for further information. The following tables present the regulatory assets and liabilities recorded on the Consolidated Balance Sheets of Duke Energy and Progress Energy. See separate tables below for balances by individual registrant. Duke Energy Progress Energy December 31, December 31, (in millions) 2020 2019 2020 2019 Regulatory Assets AROs – coal ash $ 3,408 $ 4,084 $ 1,357 $ 1,843 AROs – nuclear and other 754 739 685 668 Accrued pension and OPEB 2,317 2,391 875 897 Storm cost deferrals 1,102 1,399 893 1,214 Nuclear asset securitized balance, net 991 1,042 991 1,042 Debt fair value adjustment 950 1,019 — — Retired generation facilities 417 331 363 266 Post-in-service carrying costs (PISCC) and deferred operating expenses 402 329 51 33 Deferred asset – Lee and Harris COLA 356 388 32 38 Hedge costs deferrals 351 356 148 129 Advanced metering infrastructure (AMI) 311 338 102 114 Demand side management (DSM)/Energy Efficiency (EE) 288 343 241 241 Vacation accrual 221 214 42 41 Deferred fuel and purchased power 213 528 162 305 COR settlement 128 133 33 35 NCEMPA deferrals 124 72 124 72 Nuclear deferral 123 107 35 40 Derivatives – natural gas supply contracts 122 117 — — CEP deferral 117 76 — — Amounts due from customers 110 36 — — Qualifying facility contract buyouts 107 121 107 121 Customer connect project 105 65 55 37 Manufactured gas plant (MGP) 104 102 — — ABSAT, coal ash basin closure 98 65 27 15 Deferred pipeline integrity costs 92 79 — — Deferred severance charges 86 — 29 — Incremental COVID-19 expenses 76 — 23 — Other 589 544 158 141 Total regulatory assets 14,062 15,018 6,533 7,292 Less: current portion 1,641 1,796 758 946 Total noncurrent regulatory assets $ 12,421 $ 13,222 $ 5,775 $ 6,346 Regulatory Liabilities Net regulatory liability related to income taxes $ 7,368 $ 7,872 $ 2,411 $ 2,595 Costs of removal 5,883 5,756 2,666 2,561 AROs – nuclear and other 1,512 1,100 — — Provision for rate refunds 344 370 123 123 Accrued pension and OPEB 177 176 — — Amounts to be refunded to customers 51 34 — — Deferred fuel and purchased power 18 1 — 1 Other 1,053 739 491 275 Total regulatory liabilities 16,406 16,048 5,691 5,555 Less: current portion 1,377 784 640 330 Total noncurrent regulatory liabilities $ 15,029 $ 15,264 $ 5,051 $ 5,225 Descriptions of regulatory assets and liabilities summarized in the tables above and below follow. See tables below for recovery and amortization periods at the separate registrants. AROs – coal ash. Represents deferred depreciation and accretion related to the legal obligation to close ash basins. The costs are deferred until recovery treatment has been determined. See Notes 1 and 9 for additional information. AROs – nuclear and other. Represents regulatory assets or liabilities, including deferred depreciation and accretion, related to legal obligations associated with the future retirement of property, plant and equipment, excluding amounts related to coal ash. The AROs relate primarily to decommissioning nuclear power facilities. The amounts also include certain deferred gains and losses on NDTF investments. See Notes 1 and 9 for additional information. Accrued pension and OPEB. Accrued pension and OPEB represent regulatory assets and liabilities related to each of the Duke Energy Registrants’ respective shares of unrecognized actuarial gains and losses and unrecognized prior service cost and credit attributable to Duke Energy’s pension plans and OPEB plans. The regulatory asset or liability is amortized with the recognition of actuarial gains and losses and prior service cost and credit to net periodic benefit costs for pension and OPEB plans. The accrued pension and OPEB regulatory assets are expected to be recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 22 for additional detail. Storm cost deferrals. Represents deferred incremental costs incurred related to major weather-related events. Nuclear asset securitized balance, net. Represents the balance associated with Crystal River Unit 3 retirement approved for recovery by the FPSC on September 15, 2015, and the upfront financing costs securitized in 2016 with issuance of the associated bonds. The regulatory asset balance is net of the AFUDC equity portion. Debt fair value adjustment. Purchase accounting adjustments recorded to state the carrying value of Progress Energy and Piedmont at fair value in connection with the 2012 and 2016 mergers, respectively. Amount is amortized over the life of the related debt. Retired generation facilities. Represents amounts to be recovered for facilities that have been retired and are probable of recovery. Post-in-service carrying costs (PISCC) and deferred operating expenses. Represents deferred depreciation and operating expenses as well as carrying costs on the portion of capital expenditures placed in service but not yet reflected in retail rates as plant in service. Deferred asset – Lee and Harris COLA. Represents deferred costs incurred for the canceled Lee and Harris nuclear projects. Hedge costs deferrals. Amounts relate to unrealized gains and losses on derivatives recorded as a regulatory asset or liability, respectively, until the contracts are settled. AMI. Represents deferred costs related to the installation of AMI meters and remaining net book value of non-AMI meters to be replaced at Duke Energy Carolinas, net book value of existing meters at Duke Energy Florida , Duke Energy Progress and Duke Energy Ohio and future recovery of net book value of electromechanical meters that have been replaced with AMI meters at Duke Energy Indiana. DSM/EE. Deferred costs related to various DSM and EE programs recoverable through various mechanisms. Vacation accrual. Represents vacation entitlement, which is generally recovered in the following year. Deferred fuel and purchased power. Represents certain energy-related costs that are recoverable or refundable as approved by the applicable regulatory body. COR settlement. Represents approved COR settlements that are being amortized over the average remaining lives, at the time of approval, of the associated assets. NCEMPA deferrals. Represents retail allocated cost deferrals and returns associated with the additional ownership interest in assets acquired from NCEMPA in 2015. Nuclear deferral. Includes amounts related to levelizing nuclear plant outage costs, which allows for the recognition of nuclear outage expenses over the refueling cycle rather than when the outage occurs, resulting in the deferral of operations and maintenance costs associated with refueling. Derivatives – natural gas supply contracts . Represents costs for certain long-dated, fixed quantity forward gas supply contracts, which are recoverable through PGA clauses. CEP deferral . Represents deferred depreciation, PISCC and deferred property tax for Duke Energy Ohio Gas capital assets for the Capital Expenditure Program (CEP). Amounts due from customers. Relates primarily to margin decoupling and IMR recovery mechanisms. Qualifying facility contract buyouts. Represents termination payments for regulatory recovery through the capacity clause. Customer connect project. Represents incremental operating expenses and carrying costs on deferred amounts related to the deployment of the new customer information system known as the Customer Connect Project. MGP. Represents remediation costs incurred at former MGP sites and the deferral of costs to be incurred at Duke Energy Ohio's East End and West End sites. ABSAT, coal ash basin closure . Represents deferred depreciation and returns associated with Ash Basin Strategic Action Team (ABSAT) capital assets related to converting the ash handling system from wet to dry. Deferred pipeline integrity costs. Represents pipeline integrity management costs in compliance with federal regulations recovered through a rider mechanism. Deferred severance charges. Represents costs incurred for employees separation from Duke Energy. Incremental COVID-19 expenses. Represents incremental costs related to ensuring continuity and quality of service in a safe manner during the COVID-19 pandemic. Net regulatory liability related to income taxes. Amounts for all registrants include regulatory liabilities related primarily to impacts from the Tax Act. See Note 23 for additional information. Amounts have no immediate impact on rate base as regulatory assets are offset by deferred tax liabilities. Costs of removal. Represents funds received from customers to cover the future removal of property, plant and equipment from retired or abandoned sites as property is retired. Also includes certain deferred gains on NDTF investments. Provisions for rate refunds. Represents estimated amounts due to customers based on recording interim rates subject to refund. Amounts to be refunded to customers. Represents required rate reductions to retail customers by the applicable regulatory body. RESTRICTIONS ON THE ABILITY OF CERTAIN SUBSIDIARIES TO MAKE DIVIDENDS, ADVANCES AND LOANS TO DUKE ENERGY As a condition to the approval of merger transactions, the NCUC, PSCSC, PUCO, KPSC and IURC imposed conditions on the ability of Duke Energy Carolinas, Duke Energy Progress, Duke Energy Ohio, Duke Energy Kentucky, Duke Energy Indiana and Piedmont to transfer funds to Duke Energy through loans or advances, as well as restricted amounts available to pay dividends to Duke Energy. Certain subsidiaries may transfer funds to the Parent by obtaining approval of the respective state regulatory commissions. These conditions imposed restrictions on the ability of the public utility subsidiaries to pay cash dividends as discussed below. Duke Energy Progress and Duke Energy Florida also have restrictions imposed by their first mortgage bond indentures, which in certain circumstances, limit their ability to make cash dividends or distributions on common stock. Amounts restricted as a result of these provisions were not material at December 31, 2020. Duke Energy Indiana has certain dividend restrictions as a result of the agreement entered in January 2021 to sell a minority interest to GIC. Duke Energy Indiana will not declare a dividend prior to the first closing, which is expected to be completed in the second quarter of 2021, and will declare dividends between the first closing and the second closing, which is required to be completed no later than January 2023, in accordance with the sale agreement. See additional information in Note 1. Additionally, certain other subsidiaries of Duke Energy have restrictions on their ability to dividend, loan or advance funds to Duke Energy due to specific legal or regulatory restrictions, including, but not limited to, minimum working capital and tangible net worth requirements. The restrictions discussed below were not a material amount of Duke Energy's and Progress Energy's net assets at December 31, 2020. Duke Energy Carolinas Duke Energy Carolinas must limit cumulative distributions subsequent to mergers to (i) the amount of retained earnings on the day prior to the closing of the mergers, plus (ii) any future earnings recorded. Duke Energy Progress Duke Energy Progress must limit cumulative distributions subsequent to the mergers between Duke Energy and Progress Energy and Duke Energy and Piedmont to (i) the amount of retained earnings on the day prior to the closing of the respective mergers, plus (ii) any future earnings recorded. Duke Energy Ohio Duke Energy Ohio will not declare and pay dividends out of capital or unearned surplus without the prior authorization of the PUCO. Duke Energy Ohio received FERC and PUCO approval to pay dividends from its equity accounts that are reflective of the amount that it would have in its retained earnings account had push-down accounting for the Cinergy merger not been applied to Duke Energy Ohio’s balance sheet. The conditions include a commitment from Duke Energy Ohio that equity, adjusted to remove the impacts of push-down accounting, will not fall below 30% of total capital. Duke Energy Kentucky is required to pay dividends solely out of retained earnings and to maintain a minimum of 35% equity in its capital structure. Duke Energy Indiana Duke Energy Indiana must limit cumulative distributions subsequent to the merger between Duke Energy and Cinergy to (i) the amount of retained earnings on the day prior to the closing of the merger, plus (ii) any future earnings recorded. In addition, Duke Energy Indiana will not declare and pay dividends out of capital or unearned surplus without prior authorization of the IURC. Piedmont Piedmont must limit cumulative distributions subsequent to the acquisition of Piedmont by Duke Energy to (i) the amount of retained earnings on the day prior to the closing of the merger, plus (ii) any future earnings recorded. RATE-RELATED INFORMATION The NCUC, PSCSC, FPSC, IURC, PUCO, TPUC and KPSC approve rates for retail electric and natural gas services within their states. The FERC approves rates for electric sales to wholesale customers served under cost-based rates (excluding Ohio and Indiana), as well as sales of transmission service. The FERC also regulates certification and siting of new interstate natural gas pipeline projects. Duke Energy Carolinas and Duke Energy Progress 2021 Coal Ash Settlement On January 22 , 2021, Duke Energy Carolinas and Duke Energy Progress entered into the Coal Combustion Residuals Settlement Agreement (the “CCR Settlement Agreement”) with the North Carolina Public Staff (Public Staff), the North Carolina Attorney General’s Office and the Sierra Club (collectively, the "Settling Parties"), which was filed with the NCUC on January 25, 2021. The CCR Settlement Agreement resolves all coal ash prudence and cost recovery issues in connection with 2019 rate cases filed by Duke Energy Carolinas and Duke Energy Progress with the NCUC, as well as the equitable sharing issue on remand from the 2017 Duke Energy Carolinas and Duke Energy Progress North Carolina rate cases as a result of the December 11, 2020, North Carolina Supreme Court opinion. The settlement also provides clarity on coal ash cost recovery in North Carolina for Duke Energy Carolinas and Duke Energy Progress through January 2030 and February 2030 (the "Term"), respectively. Duke Energy Carolinas and Duke Energy Progress agreed not to seek recovery of approximately $1 billion of systemwide deferred coal ash expenditures, but will retain the ability to earn a debt and equity return during the amortization period, which shall be five years in the pending 2019 North Carolina rate cases and will be set by the NCUC in future rate case proceedings. The equity return and the amortization period on deferred coal ash costs under the 2017 Duke Energy Carolinas and Duke Energy Progress North Carolina rate cases will remain unaffected. The equity return on deferred coal ash costs under the 2019 North Carolina rate cases and future rate cases in North Carolina will be set at 150 basis points lower than the authorized return on equity then in effect, with a capital structure composed of 48% debt and 52% equity. Duke Energy Carolinas and Duke Energy Progress retain the ability to earn a full WACC return during the deferral period, which is the period from when costs are incurred until they are recovered in rates. The Settling Parties agreed that execution by Duke Energy Carolinas and Duke Energy Progress of a settlement agreement between themselves and the NCDEQ dated December 31, 2019, (the “DEQ Settlement”) and the coal ash management plans included therein or subsequently approved by DEQ are reasonable and prudent. The Settling Parties retain the right to challenge the reasonableness and prudence of actions taken by Duke Energy Carolinas and Duke Energy Progress and costs incurred to implement the scope of work agreed upon in the DEQ Settlement, after February 1, 2020, and March 1, 2020, for Duke Energy Carolinas and Duke Energy Progress, respectively. The Settling Parties further agreed to waive rights through the Term to challenge the reasonableness or prudence of Duke Energy Carolinas’ and Duke Energy Progress’ historical coal ash management practices, and to waive the right to assert any arguments that future coal ash costs, including financing costs, shall be shared between either company and customers through equitable sharing or any other rate base or return adjustment that shares the revenue requirement burden of coal ash costs not otherwise disallowed due to imprudence. The Settling Parties agreed to a sharing arrangement for future coal ash insurance litigation proceeds between Duke Energy Carolinas and Duke Energy Progress and North Carolina customers, if achieved. The settlement is subject to the review and approval of the NCUC. The Settling Parties requested an expedited review by the NCUC and anticipate an order on the pending 2019 North Carolina rate cases for Duke Energy Carolinas and Duke Energy Progress by the second quarter of 2021. On January 29, 2021, Duke Energy Carolinas and Duke Energy Progress filed joint motions with the Settling Parties seeking approval of the CCR Settlement Agreement, along with supporting testimony and exhibits from Duke Energy Carolinas and Duke Energy Progress. On February 5, 2021, the Public Staff filed testimony and exhibits supporting the CCR Settlement Agreement. As a result of the CCR Settlement Agreement, Duke Energy Carolinas and Duke Energy Progress recorded a pretax charge of approximately $454 million and $494 million, respectively, in the fourth quarter of 2020 to Impairment charges and a reversal of approximately $50 million and $102 million, respectively, to Regulated electric operating revenues on the respective Consolidated Statements of Operations. COVID-19 Filings North Carolina On March 10, 2020, Governor Roy Cooper declared a state of emergency due to the COVID-19 pandemic. On March 19, 2020, the NCUC issued an order directing that utilities under its jurisdiction suspend disconnections for nonpayment of utility bills during the state of emergency and allow for customers to enter into payment arrangements to pay off arrearages accumulated during the state of emergency after the end of the state of emergency. Additionally, to help mitigate the financial impacts of the COVID-19 pandemic on their customers, on March 19, 2020, Duke Energy Carolinas and Duke Energy Progress filed a request with the NCUC seeking authorization to waive: (1) any late payment charges incurred by a residential or nonresidential customer, effective March 21, 2020; (2) the application of fees for checks returned for insufficient funds for residential and nonresidential customers; (3) the reconnection charge when a residential or nonresidential customer seeks to have service restored for those customers whose service was recently disconnected for nonpayment and to work with customers regarding the other requirements to restore service, including re-establishment of credit; and (4) the fees and charges associated with the use of credit cards or debit cards to pay residential electric utility bills, effective March 21, 2020. The NCUC granted the companies’ request on March 20, 2020. On July 29, 2020, the NCUC issued its Order Lifting Disconnection Moratorium and Allowing Collection of Arrearages Pursuant to Special Repayment Plans. The order contained the following: (1) public utilities may resume customer disconnections due to nonpayment for bills first rendered on or after September 1, 2020, after appropriate notice; (2) the late fee moratorium will continue through the end of the state of emergency or until further order of the Commission; (3) Duke Energy utilities may reinstate fees for checks returned for insufficient funds as well as transaction fees for use of credit cards or debit cards for bills first rendered on or after September 1, 2020; and (4) no sooner than September 1, 2020, the collection of past-due or delinquent accounts accrued up to and including August 31, 2020, may proceed subject to conditions. Duke Energy Carolinas and Duke Energy Progress resumed normal billing practices as of October 1, 2020, with the exception of the billing of late payment charges. Customers were notified of the resumption of normal billing practices, the option of deferred payment arrangements and where to find assistance, if necessary. Service disconnections for nonpayment for residential customers resumed on November 2, 2020. Duke Energy Carolinas and Duke Energy Progress filed a joint petition on August 7, 2020, with the NCUC for deferral treatment of incremental costs and waived customer fees due to the COVID-19 pandemic. Comments on the joint petition were filed on November 5, 2020, and reply comments were filed on November 30, 2020. Duke Energy Carolinas and Duke Energy Progress cannot predict the outcome of this matter. South Carolina On March 13, 2020, Governor Henry McMaster declared a state of emergency due to the COVID-19 pandemic. The governor also issued a letter on March 14, 2020, to the ORS Executive Director regarding the suspension of disconnection of essential utility services for nonpayment. On March 18, 2020, the PSCSC issued an order approving such waivers, and also approved waivers for regulations related to late fees and reconnect fees. The PSCSC's order also required utilities to track the financial impacts of actions taken pursuant to such waivers for possible reporting to the PSCSC. On May 13, 2020, the ORS filed a letter with the PSCSC that included a request from Governor McMaster that utilities proceed with developing and implementing plans for phasing in normal business operations. On May 14, 2020, the PSCSC conditionally vacated the regulation waivers regarding termination of service and suspension of disconnect fees. Prior to termination, utilities are to refer past-due customers to local organizations for assistance and/or deferred payment arrangements. Duke Energy Carolinas and Duke Energy Progress filed a report on June 30, 2020, as required by PSCSC order, reporting revenue impact, costs and savings related to COVID-19 to date. On August 14, 2020, Duke Energy Carolinas and Duke Energy Progress filed a joint petition with the PSCSC for approval of an accounting order to defer incremental COVID-19 related costs incurred through June 30, 2020, and for the ongoing months during the duration of the COVID-19 pandemic. The deferral request did not include lost revenues. Updates on cost impacts were filed on September 30, 2020, and included financial impacts through the end of August 2020. On October 16, 2020, the ORS requested the PSCSC delay taking formal action on the deferral request until the ORS and any intervenors complete discovery. The PSCSC issued an order on October 21, 2020, to grant additional time to complete discovery until January 20, 2021, and to establish a procedural schedule. Updates on cost impacts were filed on December 30, 2020, and included financial impacts through November 30, 2020. On January 15, 2021, ORS requested the PSCSC suspend the dates for the ORS report and public hearing. The ORS conferred with the companies regarding the status of the docket, and the parties mutually agreed that recently enacted federal laws addressing COVID-19 aid and recovery should be studied before further action is taken in this docket. On January 27, 2021, the PSCSC voted to grant the ORS request to suspend the virtual public hearing. ORS is to file its report on or before March 29, 2021. On August 17, 2020, Duke Energy Carolinas and Duke Energy Progress filed an update on their planned return to normal operations during the COVID-19 pandemic. Normal billing practices resumed in South Carolina as of October 1, 2020, and service disconnections for nonpayment resumed on October 12, 2020. Customers were notified of the resumption of normal billing practices, the option of payment arrangements and where to find assistance, if necessary. Duke Energy Carolinas and Duke Energy Progress cannot predict the outcome of this matter. 2020 North Carolina Storm Securitization Filings On October 26, 2020, Duke Energy Carolinas and Duke Energy Progress filed a joint petition with the NCUC, as agreed to in partial settlements reached in the 2019 North Carolina Rate Cases for Duke Energy Carolinas and Duke Energy Progress, seeking authorization for the financing of the costs of each utility's storm recovery activities required as a result of Hurricane Florence, Hurricane Michael, Hurricane Dorian and Winter Storm Diego. Specifically, Duke Energy Carolinas and Duke Energy Progress requested that the NCUC find that their storm recovery costs and related financing costs are appropriately financed by debt secured by storm recovery property, and that the Commission issue financing orders by which each utility may accomplish such financing using a securitization structure. On January 27, 2021, Duke Energy Carolinas, Duke Energy Progress and the Public Staff filed an Agreement and Stipulation of Partial Settlement, which is subject to review and approval of the NCUC, resolving certain accounting issues, including agreement to support an 18- to 20-year bond period. The total revenue requirement over a proposed 20-year bond period for the storm recovery charges is approximately $287 million for Duke Energy Carolinas and $920 million for Duke Energy Progress. A remote evidentiary hearing ended on January 29, 2021, and on February 1, 2021, the NCUC granted a motion by Duke Energy Carolinas and Duke Energy Progress for a temporary 30-day waiver of the 135-day time frame for the NCUC to issue orders on the joint petition, extending the deadline for the NCUC to issue an order to no later than April 9, 2021. Duke Energy Carolinas and Duke Energy Progress cannot predict the outcome of this matter. Duke Energy Carolinas Regulatory Assets and Liabilities The following tables present the regulatory assets and liabilities recorded on Duke Energy Carolinas' Consolidated Balance Sheets. December 31, Earns/Pays Recovery/Refund (in millions) 2020 2019 a Return Period Ends Regulatory Assets (a) AROs – coal ash $ 1,414 $ 1,696 (h) (b) Accrued pension and OPEB (c) 427 477 Yes (i) Storm cost deferrals 205 178 Yes (b) Retired generation facilities (c) 11 16 Yes 2023 PISCC (c) 32 33 Yes (b) Deferred asset – Lee COLA 324 350 (b) Hedge costs deferrals (c) 174 198 Yes 2041 AMI 154 166 Yes (b) DSM/EE 46 100 (g) (g) Vacation accrual 84 80 2021 Deferred fuel and purchased power 42 222 (e) 2022 COR settlement 95 98 Yes (b) Nuclear deferral 88 67 2022 Customer connect project 50 28 Yes (b) ABSAT, coal ash basin closure 71 50 Yes (b) Deferred severance charges 57 — 2022 Incremental COVID-19 expenses 31 — Yes (b) Other 164 151 (b) Total regulatory assets 3,469 3,910 Less: current portion 473 550 Total noncurrent regulatory assets $ 2,996 $ 3,360 Regulatory Liabilities (a) Net regulatory liability related to income taxes (d) $ 2,874 $ 3,060 (b) Costs of removal (c) 1,975 1,936 Yes (f) AROs – nuclear and other 1,512 1,100 (b) Provision for rate refunds (c) 170 175 Yes Accrued pension and OPEB (c) 32 39 Yes (i) Deferred fuel and purchased power 18 — (e) 2020 Other 427 368 (b) Total regulatory liabilities 7,008 6,678 Less: current portion 473 255 Total noncurrent regulatory liabilities $ 6,535 $ 6,423 (a) Regulatory assets and liabilities are excluded from rate base unless otherwise noted. (b) The expected recovery or refund period varies or has not been determined. (c) Included in rate base. (d) Includes regulatory liabilities related to the change in the federal tax rate as a result of the Tax Act and the change in the North Carolina tax rate, both discussed in Note 23. Portions are included in rate base. (e) Pays interest on over-recovered costs in North Carolina. Includes certain purchased power costs in North Carolina and South Carolina and costs of distributed energy in South Carolina. (f) Recovered over the life of the associated assets. (g) Includes incentives on DSM/EE investments and is recovered through an annual rider mechanism. (h) Earns a debt and equity return on coal ash expenditures for North Carolina and South Carolina retail customers as permitted by various regulatory orders. (i) Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 22 for additional detail. 2017 North Carolina Rate Case On August 25, 2017, Duke Energy Carolinas filed an application with the NCUC for a rate increase for retail customers of approximately $647 million. On February 28, 2018, Duke Energy Carolinas and the Public Staff filed an Agreement and Stipulation of Partial Settlement resolving certain portions of the proceeding. Terms of the settlement included a return on equity of 9.9% and a capital structure of 52% equity and 48% debt. On June 22, 2018, the NCUC issued an order approving the Stipulation of Partial Settlement and requiring a revenue reduction. As a result of the June 22, 2018, order, Duke Energy Carolinas recorded a pretax charge of approximately $150 million to Impairment charges and Operation, maintenance and other on the Consolidated Statements of Operations. The charge was primarily related to the denial of a return on the Lee Nuclear Project and the assessment of a $70 million cost of service penalty by reducing the annual recovery of deferred coal ash costs by $14 million per year over a five-year recovery period. The North Carolina Attorney General and other parties separately filed Notices of Appeal to the North Carolina Supreme Court. The North Carolina Supreme Court consolidated the Duke Energy Carolinas and Duke Energy Progress appeals. On December 11, 2020, the North Carolina Supreme Court issued an opinion on the consolidated appeals of the 2018 Duke Energy Carolinas and Duke Energy Progress rate case orders which affirmed, in part, and reversed and remanded, in part, the NCUC’s decisions. In the Opinion, the court upheld the NCUC's decision to include coal ash costs in the cost of service, as well as the NCUC’s discretion to allow a return on the unamortized balance of coal ash costs. The court also remanded to the NCUC a single issue to consider the assessment of support for the Public Staff’s equitable sharing argument. In response to a NCUC order seeking comments on the proposed procedure on remand, on January 11, 2021, Duke Energy Carolinas, Duke Energy Progress, the Public Staff, the North Carolina Attorney General, Sierra Club and Carolina Industrial Group for Fair Utility Rates II and III filed joint comments proposing that the NCUC not hold additional evidentiary hearings, but instead rely upon existing records in the 2017 North Carolina rate cases, or in the alternative the records in the 2019 North Carolina rate cases, in deciding the issue on remand. On January 22, 2021, Duke Energy Carolinas and Duke Energy Progress entered into the CCR Settlement Agreement with the Settling Parties, which was filed with the NCUC on January 25, 2021. For information on a proposed settlement pending before the NCUC, see "2021 Coal Ash Settlement." Duke Energy Carolinas cannot predict the outcome of this matter. 2019 North Carolina Rate Case On September 30, 2019, Duke Energy Carolinas filed an application with the NCUC for a net rate increase for retail customers of approximately $291 million, which represented an approximate 6% increase in annual base revenues. The gross rate case revenue increase request was $445 million, which was offset by an EDIT rider of $154 million to return to customers North Carolina and federal EDIT resulting from recent reductions in corporate tax rates. The request for a rate increase was driven by major capital investments subsequent to the previous base rate case, coal ash pond closure costs, accelerated coal plant depreciation and deferred 2018 storm costs. Duke Energy Carolinas requested rates be effective no later than August 1, 2020. The NCUC established a procedural schedule with an evidentiary hearing to begin on March 23, 2020. On March 16, 2020, in consideration of public health and safety as a result of the COVID-19 pandemic, Duke Energy Carolinas filed a motion with the NCUC seeking a suspension of the procedural schedule in the rate case, including issuing discovery requests, and postponement of the evidentiary hearing for 60 days. Also on March 16, 2020, the NCUC issued an Order Postponing Hearing and Addressing Procedural M

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES INSURANCE General Insurance The Duke Energy Registrants have insurance and reinsurance coverage either directly or through indemnification from Duke Energy’s captive insurance company, Bison, and its affiliates, consistent with companies engaged in similar commercial operations with similar type properties. The Duke Energy Registrants’ coverage includes (i) commercial general liability coverage for liabilities arising to third parties for bodily injury and property damage; (ii) workers’ compensation; (iii) automobile liability coverage; and (iv) property coverage for all real and personal property damage. Real and personal property damage coverage excludes electric transmission and distribution lines, but includes damages arising from boiler and machinery breakdowns, earthquakes, flood damage and extra expense, but not outage or replacement power coverage. All coverage is subject to certain deductibles or retentions, sublimits, exclusions, terms and conditions common for companies with similar types of operations. The Duke Energy Registrants self-insure their electric transmission and distribution lines against loss due to storm damage and other natural disasters. As discussed further in Note 3, Duke Energy Florida maintains a storm damage reserve and has a regulatory mechanism to recover the cost of named storms on an expedited basis. The cost of the Duke Energy Registrants’ coverage can fluctuate from year to year reflecting claims history and conditions of the insurance and reinsurance markets. In the event of a loss, terms and amounts of insurance and reinsurance available might not be adequate to cover claims and other expenses incurred. Uninsured losses and other expenses, to the extent not recovered by other sources, could have a material effect on the Duke Energy Registrants’ results of operations, cash flows or financial position. Each company is responsible to the extent losses may be excluded or exceed limits of the coverage available. Nuclear Insurance Duke Energy Carolinas owns and operates McGuire and Oconee and operates and has a partial ownership interest in Catawba. McGuire and Catawba each have two reactors. Oconee has three reactors. The other joint owners of Catawba reimburse Duke Energy Carolinas for certain expenses associated with nuclear insurance per the Catawba joint owner agreements. Duke Energy Progress owns and operates Robinson, Brunswick and Harris. Robinson and Harris each have one reactor. Brunswick has two reactors. Duke Energy Florida owns Crystal River Unit 3, which permanently ceased operation in 2013 and reached a SAFSTOR condition in January 2018 after the successful transfer of all used nuclear fuel assemblies to an on-site dry cask storage facility. In the event of a loss, terms and amounts of insurance available might not be adequate to cover property damage and other expenses incurred. Uninsured losses and other expenses, to the extent not recovered by other sources, could have a material effect on Duke Energy Carolinas’, Duke Energy Progress’ and Duke Energy Florida’s results of operations, cash flows or financial position. Each company is responsible to the extent losses may be excluded or exceed limits of the coverage available. Nuclear Liability Coverage The Price-Anderson Act requires owners of nuclear reactors to provide for public nuclear liability protection per nuclear incident up to a maximum total financial protection liability. The maximum total financial protection liability, which is approximately $13.8 billion, is subject to change every five years for inflation and for the number of licensed reactors. Total nuclear liability coverage consists of a combination of private primary nuclear liability insurance coverage and a mandatory industry risk-sharing program to provide for excess nuclear liability coverage above the maximum reasonably available private primary coverage. The U.S. Congress could impose revenue-raising measures on the nuclear industry to pay claims. Primary Liability Insurance Duke Energy Carolinas and Duke Energy Progress have purchased the maximum reasonably available private primary nuclear liability insurance as required by law, which is $450 million per station. Duke Energy Florida has purchased $100 million primary nuclear liability insurance in compliance with the law. Excess Liability Program This program provides $13.3 billion of coverage per incident through the Price-Anderson Act’s mandatory industry-wide excess secondary financial protection program of risk pooling. This amount is the product of potential cumulative retrospective premium assessments of $138 million times the current 97 licensed commercial nuclear reactors in the U.S. Under this program, licensees could be assessed retrospective premiums to compensate for public nuclear liability damages in the event of a nuclear incident at any licensed facility in the U.S. Retrospective premiums may be assessed at a rate not to exceed $20.5 million per year per licensed reactor for each incident. The assessment may be subject to state premium taxes. Nuclear Property and Accidental Outage Coverage Duke Energy Carolinas, Duke Energy Progress and Duke Energy Florida are members of Nuclear Electric Insurance Limited (NEIL), an industry mutual insurance company, which provides property damage, nuclear accident decontamination and premature decommissioning insurance for each station for losses resulting from damage to its nuclear plants, either due to accidents or acts of terrorism. Additionally, NEIL provides accidental outage coverage for losses in the event of a major accidental outage at an insured nuclear station. Pursuant to regulations of the NRC, each company’s property damage insurance policies provide that all proceeds from such insurance be applied, first, to place the plant in a safe and stable condition after a qualifying accident and second, to decontaminate the plant before any proceeds can be used for decommissioning, plant repair or restoration. Losses resulting from acts of terrorism are covered as common occurrences, such that if terrorist acts occur against one or more commercial nuclear power plants insured by NEIL within a 12-month period, they would be treated as one event and the owners of the plants where the act occurred would share one full limit of liability. The full limit of liability is currently $3.2 billion. NEIL sublimits the total aggregate for all of their policies for non-nuclear terrorist events to approximately $1.8 billion. Each nuclear facility has accident property damage, nuclear accident decontamination and premature decommissioning liability insurance from NEIL with limits of $1.5 billion, except for Crystal River Unit 3. Crystal River Unit 3’s limit is $50 million and is on an actual cash value basis. All nuclear facilities except for Catawba and Crystal River Unit 3 also share an additional $1.25 billion nuclear accident insurance limit above their dedicated underlying limit. This shared additional excess limit is not subject to reinstatement in the event of a loss. Catawba has a dedicated $1.25 billion of additional nuclear accident insurance limit above its dedicated underlying limit. Catawba and Oconee also have an additional $750 million of non-nuclear accident property damage limit. All coverages are subject to sublimits and significant deductibles. NEIL’s Accidental Outage policy provides some coverage, similar to business interruption, for losses in the event of a major accident property damage outage of a nuclear unit. Coverage is provided on a weekly limit basis after a significant waiting period deductible and at 100% of the applicable weekly limits for 52 weeks and 80% of the applicable weekly limits for up to the next 110 weeks. Coverage is provided until these applicable weekly periods are met, where the accidental outage policy limit will not exceed $490 million for McGuire and Catawba, $434 million for Harris, $420 million for Brunswick, $392 million for Oconee and $336 million for Robinson. NEIL sublimits the accidental outage recovery up to the first 104 weeks of coverage not to exceed $328 million from non-nuclear accidental property damage. Coverage amounts decrease in the event more than one unit at a station is out of service due to a common accident. All coverages are subject to sublimits and significant deductibles. Potential Retroactive Premium Assessments In the event of NEIL losses, NEIL’s board of directors may assess member companies' retroactive premiums of amounts up to 10 times their annual premiums for up to six years after a loss. NEIL has never exercised this assessment. The maximum aggregate annual retrospective premium obligations for Duke Energy Carolinas, Duke Energy Progress and Duke Energy Florida are $156 million, $93 million and $1 million, respectively. Duke Energy Carolinas' maximum assessment amount includes 100% of potential obligations to NEIL for jointly owned reactors. Duke Energy Carolinas would seek reimbursement from the joint owners for their portion of these assessment amounts. ENVIRONMENTAL The Duke Energy Registrants are subject to federal, state and local laws regarding air and water quality, hazardous and solid waste disposal, coal ash and other environmental matters. These laws can be changed from time to time, imposing new obligations on the Duke Energy Registrants. The following environmental matters impact all of the Duke Energy Registrants. Remediation Activities In addition to the ARO recorded as a result of various environmental regulations, discussed in Note 9, the Duke Energy Registrants are responsible for environmental remediation at various sites. These include certain properties that are part of ongoing operations and sites formerly owned or used by Duke Energy entities. These sites are in various stages of investigation, remediation and monitoring. Managed in conjunction with relevant federal, state and local agencies, remediation activities vary based upon site conditions and location, remediation requirements, complexity and sharing of responsibility. If remediation activities involve joint and several liability provisions, strict liability, or cost recovery or contribution actions, the Duke Energy Registrants could potentially be held responsible for environmental impacts caused by other potentially responsible parties and may also benefit from insurance policies or contractual indemnities that cover some or all cleanup costs. Liabilities are recorded when losses become probable and are reasonably estimable. The total costs that may be incurred cannot be estimated because the extent of environmental impact, allocation among potentially responsible parties, remediation alternatives and/or regulatory decisions have not yet been determined at all sites. Additional costs associated with remediation activities are likely to be incurred in the future and could be significant. Costs are typically expensed as Operation, maintenance and other in the Consolidated Statements of Operations unless regulatory recovery of the costs is deemed probable. The following tables contain information regarding reserves for probable and estimable costs related to the various environmental sites. These reserves are recorded in Other within Other Noncurrent Liabilities on the Consolidated Balance Sheets. (in millions) December 31, 2020 December 31, 2019 Reserves for Environmental Remediation Duke Energy $ 75 $ 58 Duke Energy Carolinas 19 11 Progress Energy 19 16 Duke Energy Progress 6 4 Duke Energy Florida 12 9 Duke Energy Ohio 22 19 Duke Energy Indiana 6 4 Piedmont 10 8 Additional losses in excess of recorded reserves that could be incurred for the stages of investigation, remediation and monitoring for environmental sites that have been evaluated at this time are not material except as presented in the table below. (in millions) Duke Energy $ 25 Duke Energy Carolinas 12 Duke Energy Ohio 4 Piedmont 2 LITIGATION Duke Energy Carolinas and Duke Energy Progress Coal Ash Insurance Coverage Litigation In March 2017, Duke Energy Carolinas and Duke Energy Progress filed a civil action in the North Carolina Business Court against various insurance providers. The lawsuit seeks payment for coal ash related liabilities covered by third-party liability insurance policies. The insurance policies were issued between 1971 and 1986 and provide third-party liability insurance for property damage. The civil action seeks damages for breach of contract and indemnification for costs arising from the Coal Ash Act and the EPA CCR rule at 15 coal-fired plants in North Carolina and Sout h Carolina. Fact discovery has been completed. The parties filed dispositive pretrial motions relating to key legal issues on December 4, 2020. Hearings on these motions are scheduled to begin on February 24, 2021, and trial is scheduled for January 24, 2022. Duke Energy Carolinas and Duke Energy Progress cannot predict the outcome of this matter. Duke Energy Carolinas NTE Carolinas II, LLC Litigation In November 2017, Duke Energy Carolinas entered into a standard FERC large generator interconnection agreement (LGIA) with NTE Carolinas II, LLC (NTE), a company that proposed to build a combined-cycle natural gas plant in Rockingham County, North Carolina. On September 6, 2019, Duke Energy Carolinas filed a lawsuit in Mecklenburg County Superior Court against NTE for breach of contract and alleging that NTE's failure to pay benchmark payments for Duke Energy Carolinas' transmission system upgrades required under the interconnection agreement constituted a termination of the interconnection agreement. Duke Energy Carolinas is seeking a monetary judgment against NTE because NTE failed to make multiple milestone payments. The lawsuit was moved to federal court in North Carolina. NTE filed a motion to dismiss Duke Energy Carolinas’ complaint and brought counterclaims alleging anti-competitive conduct and violations of state and federal statutes. Duke Energy Carolinas filed a motion to dismiss NTE's counterclaims. On May 21, 2020, in response to a NTE petition challenging Duke Energy Carolina's termination of the LGIA, FERC issued a ruling (i) that it has exclusive jurisdiction to determine whether a transmission provider may terminate a LGIA, (ii) FERC approval is required to terminate a conforming LGIA if objected to by the interconnection customer, and (iii) Duke Energy may not announce the termination of a conforming LGIA unless FERC has approved the termination. On August 17, 2020, the court denied both NTE’s and Duke Energy Carolinas’ Motion to Dismiss. The parties are in active discovery and trial is scheduled for June 20, 2022. Duke Energy Carolinas cannot predict the outcome of this matter. Asbestos-related Injuries and Damages Claims Duke Energy Carolinas has experienced numerous claims for indemnification and medical cost reimbursement related to asbestos exposure. These claims relate to damages for bodily injuries alleged to have arisen from exposure to or use of asbestos in connection with construction and maintenance activities conducted on its electric generation plants prior to 1985. As of December 31, 2020, there were 145 asserted claims for non-malignant cases with the cumulative relief sought of up to $39 million and 56 asserted claims for malignant cases with the cumulative relief sought of up to $20 million. Based on Duke Energy Carolinas’ experience, it is expected that the ultimate resolution of most of these claims likely will be less than the amount claimed. Duke Energy Carolinas has recognized asbestos-related reserves of $572 million and $604 million at December 31, 2020, and 2019, respectively. These reserves are classified in Other within Other Noncurrent Liabilities and Other within Current Liabilities on the Consolidated Balance Sheets. These reserves are based upon Duke Energy Carolinas' best estimate for current and future asbestos claims through 2040 and are recorded on an undiscounted basis. In light of the uncertainties inherent in a longer-term forecast, management does not believe they can reasonably estimate the indemnity and medical costs that might be incurred after 2040 related to such potential claims. It is possible Duke Energy Carolinas may incur asbestos liabilities in excess of the recorded reserves. Duke Energy Carolinas has third-party insurance to cover certain losses related to asbestos-related injuries and damages above an aggregate self-insured retention. Duke Energy Carolinas’ cumulative payments began to exceed the self-insurance retention in 2008. Future payments up to the policy limit will be reimbursed by the third-party insurance carrier. The insurance policy limit for potential future insurance recoveries indemnification and medical cost claim payments is $714 million in excess of the self-insured retention. Receivables for insurance recoveries were $704 million and $742 million at December 31, 2020, and 2019, respectively. These amounts are classified in Other within Other Noncurrent Assets and Receivables within Current Assets on the Consolidated Balance Sheets. Duke Energy Carolinas is not aware of any uncertainties regarding the legal sufficiency of insurance claims. Duke Energy Carolinas believes the insurance recovery asset is probable of recovery as the insurance carrier continues to have a strong financial strength rating. As described in Note 1, Duke Energy adopted the new guidance for credit losses effective January 1, 2020, using the modified retrospective method of adoption, which does not require restatement of prior year reported results. The reserve for credit losses for insurance receivables for the asbestos-related injuries and damages based on adoption of the new standard is $15 million for Duke Energy and Duke Energy Carolinas as of December 31, 2020. The insurance receivable is evaluated based on the risk of default and the historical losses, current conditions and expected conditions around collectability. Management evaluates the risk of default annually based on payment history, credit rating and changes in the risk of default from credit agencies. Duke Energy Progress and Duke Energy Florida Spent Nuclear Fuel Matters On June 18, 2018, Duke Energy Progress and Duke Energy Florida sued the U.S. in the U.S. Court of Federal Claims for damages incurred for the period 2014 through 2018. The lawsuit claimed the Department of Energy breached a contract in failing to accept spent nuclear fuel under the Nuclear Waste Policy Act of 1982 and asserted damages for the cost of on-site storage in the amount of $100 million and $200 million for Duke Energy Progress and Duke Energy Florida, respectively. Discovery is ongoing and a trial is expected to occur in 2021. Duke Energy Florida Power Purchase Dispute Arbitration Duke Energy Florida, on behalf of its customers, entered into a PPA for the purchase of firm capacity and energy from a qualifying facility under the Public Utilities Regulatory Policies Act of 1978. Duke Energy Florida determined the qualifying facility did not perform in accordance with the PPA, and Duke Energy Florida terminated the PPA. The qualifying facility counterparty filed a confidential American Arbitration Association (AAA) arbitration demand, challenging the termination of the PPA and seeking damages. Duke Energy Florida denies liability and is vigorously defending the arbitration claim. The final arbitration hearing occurred during the week of December 7, 2020. An arbitral award has not yet been issued. Duke Energy Florida cannot predict the outcome of this matter. Duke Energy Indiana Coal Ash Basin Closure Plan Appeal On January 27, 2020, Hoosier Environmental Council filed a Petition for Administrative Review with the Indiana Office of Environmental Adjudication (the court) challenging the Indiana Department of Environmental Management’s December 10, 2019, partial approval of Duke Energy Indiana’s ash pond closure plan. On March 11, 2020, Duke Energy Indiana filed a Motion to Dismiss. On May 5, 2020, the court denied the motion. The parties have completed discovery and will now prepare to file dispositive motions. Summary judgment briefing will be completed by March 30, 2021. If these claims survive dispositive motions, a hearing is scheduled for April 26, 2021. Duke Energy Indiana cannot predict the outcome of this matter. See Note 9 for additional information. Other Litigation and Legal Proceedings The Duke Energy Registrants are involved in other legal, tax and regulatory proceedings arising in the ordinary course of business, some of which involve significant amounts. The Duke Energy Registrants believe the final disposition of these proceedings will not have a material effect on their results of operations, cash flows or financial position. The table below presents recorded reserves based on management’s best estimate of probable loss for legal matters, excluding asbestos-related reserves. Reserves are classified on the Consolidated Balance Sheets in Other within Other Noncurrent Liabilities and Other within Current Liabilities. The reasonably possible range of loss in excess of recorded reserves is not material, other than as described above. December 31, (in millions) 2020 2019 Reserves for Legal Matters Duke Energy $ 68 $ 62 Duke Energy Carolinas 2 2 Progress Energy 61 55 Duke Energy Progress 13 12 Duke Energy Florida 28 22 Piedmont 1 1 OTHER COMMITMENTS AND CONTINGENCIES General As part of their normal business, the Duke Energy Registrants are party to various financial guarantees, performance guarantees and other contractual commitments to extend guarantees of credit and other assistance to various subsidiaries, investees and other third parties. These guarantees involve elements of performance and credit risk, which are not fully recognized on the Consolidated Balance Sheets and have uncapped maximum potential payments. See Note 7 for more information. Purchase Obligations Purchased Power Duke Energy Progress, Duke Energy Florida and Duke Energy Ohio have ongoing purchased power contracts, including renewable energy contracts, with other utilities, wholesale marketers, co-generators and qualified facilities. These purchased power contracts generally provide for capacity and energy payments. In addition, Duke Energy Progress and Duke Energy Florida have various contracts to secure transmission rights. The following table presents executory purchased power contracts with terms exceeding one year, excluding contracts classified as leases. Minimum Purchase Amount at December 31, 2020 Contract (in millions) Expiration 2021 2022 2023 2024 2025 Thereafter Total Duke Energy Progress (a) 2025-2032 $ 66 $ 73 $ 66 $ 67 $ 69 $ 69 $ 410 Duke Energy Florida (b) 2023-2025 335 354 374 262 91 — 1,416 Duke Energy Ohio (c)(d) 2022 130 55 — — — — 185 (a) Contracts represent either 100% of net plant output or vary. (b) Contracts represent 100% of net plant output. (c) Contracts represent between 1% and 11% of net plant output. (d) Excludes PPA with OVEC. See Note 17 for additional information. Gas Supply and Capacity Contracts Duke Energy Ohio and Piedmont routinely enter into long-term natural gas supply commodity and capacity commitments and other agreements that commit future cash flows to acquire services needed in their businesses. These commitments include pipeline and storage capacity contracts and natural gas supply contracts to provide service to customers. Costs arising from the natural gas supply commodity and capacity commitments, while significant, are pass-through costs to customers and are generally fully recoverable through the fuel adjustment or PGA procedures and prudence reviews in North Carolina and South Carolina and under the Tennessee Incentive Plan in Tennessee. In the Midwest, these costs are recovered via the Gas Cost Recovery Rate in Ohio or the Gas Cost Adjustment Clause in Kentucky. The time periods for fixed payments under pipeline and storage capacity contracts are u p to 15 years. The time periods for fixed payments under natural gas supply contracts are up to six years. The time period for the natural gas supply purchase commitments is up to 11 years. Certain storage and pipeline capacity contracts require the payment of demand charges that are based on rates approved by the FERC in order to maintain rights to access the natural gas storage or pipeline capacity on a firm basis during the contract term. The demand charges that are incurred in each period are recognized in the Consolidated Statements of Operations and Comprehensive Income as part of natural gas purchases and are included in Cost of natural gas. The following table presents future unconditional purchase obligations under natural gas supply and capacity contracts as of December 31, 2020. (in millions) Duke Energy Duke Energy Ohio Piedmont 2021 $ 311 $ 41 $ 270 2022 270 28 242 2023 197 20 177 2024 139 17 122 2025 125 14 111 Thereafter 662 60 602 Total $ 1,704 $ 180 $ 1,524

Leases

Leases	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Leases	LEASES As part of its operations, Duke Energy leases certain aircraft, space on communication towers, industrial equipment, fleet vehicles, fuel transportation (barges and railcars), land and office space under various terms and expiration dates. Additionally, Duke Energy Carolinas, Duke Energy Progress and Duke Energy Indiana have finance leases related to firm natural gas pipeline transportation capacity. Duke Energy Progress and Duke Energy Florida have entered into certain PPAs, which are classified as finance and operating leases. Duke Energy has certain lease agreements, which include variable lease payments that are based on the usage of an asset. These variable lease payments are not included in the measurement of the ROU assets or operating lease liabilities on the Consolidated Financial Statements. Certain Duke Energy lease agreements include options for renewal and early termination. The intent to renew a lease varies depending on the lease type and asset. Renewal options that are reasonably certain to be exercised are included in the lease measurements. The decision to terminate a lease early is dependent on various economic factors. No termination options have been included in any of the lease measurements. Duke Energy Carolinas entered into a sale-leaseback arrangement in December 2019, to construct and occupy an office tower. The lease agreement was evaluated as a sale-leaseback of real estate and it was determined that the transaction did not qualify for sale-leaseback accounting. As a result, the transaction is being accounted for as a financing. For this transaction, Duke Energy Carolinas will continue to record the real estate on the Consolidated Balance Sheets within Property, Plant and Equipment as if it were the legal owner and will continue to recognize depreciation expense over the estimated useful life. In addition, a liability will be recorded for the failed sale-leaseback obligation within Long-Term Debt on the Consolidated Balance Sheets, with the monthly lease payments commencing after the construction phase being split between interest expense and principal pay down of the debt. Duke Energy operates various renewable energy projects and sells the generated output to utilities, electric cooperatives, municipalities and commercial and industrial customers through long-term PPAs. In certain situations, these PPAs and the associated renewable energy projects qualify as operating leases. Rental income from these leases is accounted for as Nonregulated electric and other revenues in the Consolidated Statements of Operations. There are no minimum lease payments as all payments are contingent based on actual electricity generated by the renewable energy projects. Contingent lease payments were $275 million, $264 million and $268 million for the years ended December 31, 2020, 2019, and 2018, respectively. Renewable energy projects owned by Duke Energy and accounted for as operating leases had a cost basis of $3,335 million and $3,349 million and accumulated depreciation of $848 million and $721 million at December 31, 2020, and 2019, respectively. These assets are principally classified as nonregulated electric generation and transmission assets. Piedmont has certain agreements with Duke Energy Carolinas for the construction and transportation of natural gas pipelines to supply its natural gas plant needs. Piedmont accounts for these pipeline lateral contracts as sales-type leases since the present value of the sum of the lease payments equals the fair value of the assets. These pipeline lateral assets owned by Piedmont had a current net investment basis of $2 million and $4 million as of December 31, 2020, and 2019, respectively, and a long-term net investment basis of $205 million and $70 million as of December 31, 2020, and 2019, respectively. These assets are classified in Other, within Current Assets and Other Noncurrent Assets, respectively, on Piedmont's Consolidated Balance Sheets. Duke Energy Carolinas accounts for the contracts as finance leases. The activity for these contracts is eliminated in consolidation at Duke Energy. The following tables present the components of lease expense. Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Operating lease expense (a) $ 283 $ 53 $ 162 $ 72 $ 90 $ 11 $ 19 $ 7 Short-term lease expense (a) 4 — 2 1 1 — 1 — Variable lease expense (a) 30 13 13 5 8 — 1 1 Finance lease expense Amortization of leased assets (b) 119 8 24 6 18 — 1 — Interest on lease liabilities (c) 61 30 44 37 7 — — — Total finance lease expense 180 38 68 43 25 — 1 — Total lease expense $ 497 $ 104 $ 245 $ 121 $ 124 $ 11 $ 22 $ 8 (a) Included in Operations, maintenance and other or, for barges and railcars, Fuel used in electric generation and purchased power on the Consolidated Statements of Operations. (b) Included in Depreciation and amortization on the Consolidated Statements of Operations. (c) Included in Interest Expense on the Consolidated Statements of Operations. Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Operating lease expense (a) $ 292 $ 47 $ 161 $ 69 $ 92 $ 11 $ 20 $ 5 Short-term lease expense (a) 16 5 9 4 5 1 2 — Variable lease expense (a) 47 22 22 16 6 — 1 1 Finance lease expense Amortization of leased assets (b) 111 6 21 5 16 1 — — Interest on lease liabilities (c) 61 15 42 33 9 — 1 — Total finance lease expense 172 21 63 38 25 1 1 — Total lease expense $ 527 $ 95 $ 255 $ 127 $ 128 $ 13 $ 24 $ 6 (a) Included in Operations, maintenance and other or, for barges and railcars, Fuel used in electric generation and purchased power on the Consolidated Statements of Operations. (b) Included in Depreciation and amortization on the Consolidated Statements of Operations. (c) Included in Interest Expense on the Consolidated Statements of Operations. The following table presents rental expense for operating leases, as reported under the former lease standard. These amounts are included in Operation, maintenance and other and Fuel used in electric generation and purchased power on the Consolidated Statements of Operations. Year Ended (in millions) December 31, 2018 Duke Energy $ 268 Duke Energy Carolinas 49 Progress Energy 143 Duke Energy Progress 75 Duke Energy Florida 68 Duke Energy Ohio 13 Duke Energy Indiana 21 Piedmont 11 The following table presents operating lease maturities and a reconciliation of the undiscounted cash flows to operating lease liabilities. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont 2021 $ 229 $ 24 $ 99 $ 44 $ 55 $ 2 $ 5 $ 5 2022 212 22 95 40 55 2 4 5 2023 202 20 95 41 54 2 4 5 2024 186 14 95 41 54 2 4 5 2025 162 10 85 31 54 2 4 5 Thereafter 870 51 376 252 124 20 59 — Total operating lease payments 1,861 141 845 449 396 30 80 25 Less: present value discount (344) (24) (149) (95) (54) (9) (24) (2) Total operating lease liabilities (a) $ 1,517 $ 117 $ 696 $ 354 $ 342 $ 21 $ 56 $ 23 (a) Certain operating lease payments include renewal options that are reasonably certain to be exercised. The following table presents finance lease maturities and a reconciliation of the undiscounted cash flows to finance lease liabilities. December 31, 2020 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Indiana 2021 $ 186 $ 38 $ 68 $ 43 $ 25 $ 1 2022 173 38 68 43 25 1 2023 174 38 68 43 25 1 2024 119 38 52 43 9 1 2025 51 38 48 43 5 1 Thereafter 762 502 481 475 6 26 Total finance lease payments 1,465 692 785 690 95 31 Less: amounts representing interest (620) (398) (408) (394) (14) (21) Total finance lease liabilities $ 845 $ 294 $ 377 $ 296 $ 81 $ 10 The following tables contain additional information related to leases. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Classification Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Assets Operating Operating lease ROU assets, net $ 1,524 $ 110 $ 690 $ 346 $ 344 $ 20 $ 55 $ 20 Finance Net property, plant and equipment 797 312 416 297 119 — 7 — Total lease assets $ 2,321 $ 422 $ 1,106 $ 643 $ 463 $ 20 $ 62 $ 20 Liabilities Current Operating Other current liabilities $ 177 $ 20 $ 73 $ 31 $ 42 $ 1 $ 3 $ 4 Finance Current maturities of long-term debt 129 5 26 7 19 — — — Noncurrent Operating Operating lease liabilities 1,340 97 623 323 300 20 53 19 Finance Long-Term Debt 716 289 351 289 62 — 10 — Total lease liabilities $ 2,362 $ 411 $ 1,073 $ 650 $ 423 $ 21 $ 66 $ 23 December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Classification Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Assets Operating Operating lease ROU assets, net $ 1,658 $ 123 $ 788 $ 387 $ 401 $ 21 $ 57 $ 24 Finance Net property, plant and equipment 926 198 443 308 135 — 7 — Total lease assets $ 2,584 $ 321 $ 1,231 $ 695 $ 536 $ 21 $ 64 $ 24 Liabilities Current Operating Other current liabilities $ 208 $ 27 $ 95 $ 37 $ 58 $ 1 $ 3 $ 4 Finance Current maturities of long-term debt 119 7 24 6 18 — — — Noncurrent Operating Operating lease liabilities 1,432 102 697 354 343 21 55 23 Finance Long-Term Debt 850 172 381 301 80 — 10 — Total lease liabilities $ 2,609 $ 308 $ 1,197 $ 698 $ 499 $ 22 $ 68 $ 27 Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Cash paid for amounts included in the measurement of lease liabilities (a) Operating cash flows from operating leases $ 271 $ 31 $ 124 $ 52 $ 72 $ 2 $ 6 $ 5 Operating cash flows from finance leases 61 30 44 37 7 — — — Financing cash flows from finance leases 119 8 24 6 18 — 1 — Lease assets obtained in exchange for new lease liabilities (non-cash) Operating (b) $ 116 $ 17 $ — $ — $ — $ — $ 1 $ — Finance 125 125 — — — — — — (a) No amounts were classified as investing cash flows from operating leases for the year ended December 31, 2020. (b) Does not include ROU assets recorded as a result of the adoption of the new lease standard. Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Cash paid for amounts included in the measurement of lease liabilities (a) Operating cash flows from operating leases $ 285 $ 34 $ 131 $ 53 $ 78 $ 2 $ 7 $ 7 Operating cash flows from finance leases 61 15 42 33 9 — 1 — Financing cash flows from finance leases 111 6 21 5 16 1 — — Lease assets obtained in exchange for new lease liabilities (non-cash) Operating (b) $ 194 $ 44 $ 30 $ 30 $ — $ — $ — $ 1 Finance 251 76 175 175 — — — — (a) No amounts were classified as investing cash flows from operating leases for the year ended December 31, 2019. (b) Does not include ROU assets recorded as a result of the adoption of the new lease standard. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Weighted average remaining lease term (years) Operating leases 10 9 10 12 8 17 18 5 Finance leases 13 19 15 17 11 — 25 — Weighted average discount rate (a) Operating leases 3.8 % 3.4 % 3.8 % 3.9 % 3.8 % 4.2 % 4.2 % 3.6 % Finance leases 8.4 % 11.6 % 11.9 % 12.4 % 8.2 % — % 11.9 % — % (a) The discount rate is calculated using the rate implicit in a lease if it is readily determinable. Generally, the rate used by the lessor is not provided to Duke Energy and in these cases the incremental borrowing rate is used. Duke Energy will typically use its fully collateralized incremental borrowing rate as of the commencement date to calculate and record the lease. The incremental borrowing rate is influenced by the lessee’s credit rating and lease term and as such may differ for individual leases, embedded leases or portfolios of leased assets. December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Weighted average remaining lease term (years) Operating leases 11 9 10 12 8 17 18 6 Finance leases 13 19 16 18 11 — 26 — Weighted average discount rate (a) Operating leases 3.9 % 3.5 % 3.8 % 3.9 % 3.8 % 4.2 % 4.1 % 3.6 % Finance leases 8.1 % 11.8 % 11.9 % 12.4 % 8.3 % — % 11.9 % — % (a) The discount rate is calculated using the rate implicit in a lease if it is readily determinable. Generally, the rate used by the lessor is not provided to Duke Energy and in these cases the incremental borrowing rate is used. Duke Energy will typically use its fully collateralized incremental borrowing rate as of the commencement date to calculate and record the lease. The incremental borrowing rate is influenced by the lessee’s credit rating and lease term and as such may differ for individual leases, embedded leases or portfolios of leased assets.
Leases	LEASES As part of its operations, Duke Energy leases certain aircraft, space on communication towers, industrial equipment, fleet vehicles, fuel transportation (barges and railcars), land and office space under various terms and expiration dates. Additionally, Duke Energy Carolinas, Duke Energy Progress and Duke Energy Indiana have finance leases related to firm natural gas pipeline transportation capacity. Duke Energy Progress and Duke Energy Florida have entered into certain PPAs, which are classified as finance and operating leases. Duke Energy has certain lease agreements, which include variable lease payments that are based on the usage of an asset. These variable lease payments are not included in the measurement of the ROU assets or operating lease liabilities on the Consolidated Financial Statements. Certain Duke Energy lease agreements include options for renewal and early termination. The intent to renew a lease varies depending on the lease type and asset. Renewal options that are reasonably certain to be exercised are included in the lease measurements. The decision to terminate a lease early is dependent on various economic factors. No termination options have been included in any of the lease measurements. Duke Energy Carolinas entered into a sale-leaseback arrangement in December 2019, to construct and occupy an office tower. The lease agreement was evaluated as a sale-leaseback of real estate and it was determined that the transaction did not qualify for sale-leaseback accounting. As a result, the transaction is being accounted for as a financing. For this transaction, Duke Energy Carolinas will continue to record the real estate on the Consolidated Balance Sheets within Property, Plant and Equipment as if it were the legal owner and will continue to recognize depreciation expense over the estimated useful life. In addition, a liability will be recorded for the failed sale-leaseback obligation within Long-Term Debt on the Consolidated Balance Sheets, with the monthly lease payments commencing after the construction phase being split between interest expense and principal pay down of the debt. Duke Energy operates various renewable energy projects and sells the generated output to utilities, electric cooperatives, municipalities and commercial and industrial customers through long-term PPAs. In certain situations, these PPAs and the associated renewable energy projects qualify as operating leases. Rental income from these leases is accounted for as Nonregulated electric and other revenues in the Consolidated Statements of Operations. There are no minimum lease payments as all payments are contingent based on actual electricity generated by the renewable energy projects. Contingent lease payments were $275 million, $264 million and $268 million for the years ended December 31, 2020, 2019, and 2018, respectively. Renewable energy projects owned by Duke Energy and accounted for as operating leases had a cost basis of $3,335 million and $3,349 million and accumulated depreciation of $848 million and $721 million at December 31, 2020, and 2019, respectively. These assets are principally classified as nonregulated electric generation and transmission assets. Piedmont has certain agreements with Duke Energy Carolinas for the construction and transportation of natural gas pipelines to supply its natural gas plant needs. Piedmont accounts for these pipeline lateral contracts as sales-type leases since the present value of the sum of the lease payments equals the fair value of the assets. These pipeline lateral assets owned by Piedmont had a current net investment basis of $2 million and $4 million as of December 31, 2020, and 2019, respectively, and a long-term net investment basis of $205 million and $70 million as of December 31, 2020, and 2019, respectively. These assets are classified in Other, within Current Assets and Other Noncurrent Assets, respectively, on Piedmont's Consolidated Balance Sheets. Duke Energy Carolinas accounts for the contracts as finance leases. The activity for these contracts is eliminated in consolidation at Duke Energy. The following tables present the components of lease expense. Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Operating lease expense (a) $ 283 $ 53 $ 162 $ 72 $ 90 $ 11 $ 19 $ 7 Short-term lease expense (a) 4 — 2 1 1 — 1 — Variable lease expense (a) 30 13 13 5 8 — 1 1 Finance lease expense Amortization of leased assets (b) 119 8 24 6 18 — 1 — Interest on lease liabilities (c) 61 30 44 37 7 — — — Total finance lease expense 180 38 68 43 25 — 1 — Total lease expense $ 497 $ 104 $ 245 $ 121 $ 124 $ 11 $ 22 $ 8 (a) Included in Operations, maintenance and other or, for barges and railcars, Fuel used in electric generation and purchased power on the Consolidated Statements of Operations. (b) Included in Depreciation and amortization on the Consolidated Statements of Operations. (c) Included in Interest Expense on the Consolidated Statements of Operations. Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Operating lease expense (a) $ 292 $ 47 $ 161 $ 69 $ 92 $ 11 $ 20 $ 5 Short-term lease expense (a) 16 5 9 4 5 1 2 — Variable lease expense (a) 47 22 22 16 6 — 1 1 Finance lease expense Amortization of leased assets (b) 111 6 21 5 16 1 — — Interest on lease liabilities (c) 61 15 42 33 9 — 1 — Total finance lease expense 172 21 63 38 25 1 1 — Total lease expense $ 527 $ 95 $ 255 $ 127 $ 128 $ 13 $ 24 $ 6 (a) Included in Operations, maintenance and other or, for barges and railcars, Fuel used in electric generation and purchased power on the Consolidated Statements of Operations. (b) Included in Depreciation and amortization on the Consolidated Statements of Operations. (c) Included in Interest Expense on the Consolidated Statements of Operations. The following table presents rental expense for operating leases, as reported under the former lease standard. These amounts are included in Operation, maintenance and other and Fuel used in electric generation and purchased power on the Consolidated Statements of Operations. Year Ended (in millions) December 31, 2018 Duke Energy $ 268 Duke Energy Carolinas 49 Progress Energy 143 Duke Energy Progress 75 Duke Energy Florida 68 Duke Energy Ohio 13 Duke Energy Indiana 21 Piedmont 11 The following table presents operating lease maturities and a reconciliation of the undiscounted cash flows to operating lease liabilities. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont 2021 $ 229 $ 24 $ 99 $ 44 $ 55 $ 2 $ 5 $ 5 2022 212 22 95 40 55 2 4 5 2023 202 20 95 41 54 2 4 5 2024 186 14 95 41 54 2 4 5 2025 162 10 85 31 54 2 4 5 Thereafter 870 51 376 252 124 20 59 — Total operating lease payments 1,861 141 845 449 396 30 80 25 Less: present value discount (344) (24) (149) (95) (54) (9) (24) (2) Total operating lease liabilities (a) $ 1,517 $ 117 $ 696 $ 354 $ 342 $ 21 $ 56 $ 23 (a) Certain operating lease payments include renewal options that are reasonably certain to be exercised. The following table presents finance lease maturities and a reconciliation of the undiscounted cash flows to finance lease liabilities. December 31, 2020 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Indiana 2021 $ 186 $ 38 $ 68 $ 43 $ 25 $ 1 2022 173 38 68 43 25 1 2023 174 38 68 43 25 1 2024 119 38 52 43 9 1 2025 51 38 48 43 5 1 Thereafter 762 502 481 475 6 26 Total finance lease payments 1,465 692 785 690 95 31 Less: amounts representing interest (620) (398) (408) (394) (14) (21) Total finance lease liabilities $ 845 $ 294 $ 377 $ 296 $ 81 $ 10 The following tables contain additional information related to leases. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Classification Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Assets Operating Operating lease ROU assets, net $ 1,524 $ 110 $ 690 $ 346 $ 344 $ 20 $ 55 $ 20 Finance Net property, plant and equipment 797 312 416 297 119 — 7 — Total lease assets $ 2,321 $ 422 $ 1,106 $ 643 $ 463 $ 20 $ 62 $ 20 Liabilities Current Operating Other current liabilities $ 177 $ 20 $ 73 $ 31 $ 42 $ 1 $ 3 $ 4 Finance Current maturities of long-term debt 129 5 26 7 19 — — — Noncurrent Operating Operating lease liabilities 1,340 97 623 323 300 20 53 19 Finance Long-Term Debt 716 289 351 289 62 — 10 — Total lease liabilities $ 2,362 $ 411 $ 1,073 $ 650 $ 423 $ 21 $ 66 $ 23 December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Classification Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Assets Operating Operating lease ROU assets, net $ 1,658 $ 123 $ 788 $ 387 $ 401 $ 21 $ 57 $ 24 Finance Net property, plant and equipment 926 198 443 308 135 — 7 — Total lease assets $ 2,584 $ 321 $ 1,231 $ 695 $ 536 $ 21 $ 64 $ 24 Liabilities Current Operating Other current liabilities $ 208 $ 27 $ 95 $ 37 $ 58 $ 1 $ 3 $ 4 Finance Current maturities of long-term debt 119 7 24 6 18 — — — Noncurrent Operating Operating lease liabilities 1,432 102 697 354 343 21 55 23 Finance Long-Term Debt 850 172 381 301 80 — 10 — Total lease liabilities $ 2,609 $ 308 $ 1,197 $ 698 $ 499 $ 22 $ 68 $ 27 Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Cash paid for amounts included in the measurement of lease liabilities (a) Operating cash flows from operating leases $ 271 $ 31 $ 124 $ 52 $ 72 $ 2 $ 6 $ 5 Operating cash flows from finance leases 61 30 44 37 7 — — — Financing cash flows from finance leases 119 8 24 6 18 — 1 — Lease assets obtained in exchange for new lease liabilities (non-cash) Operating (b) $ 116 $ 17 $ — $ — $ — $ — $ 1 $ — Finance 125 125 — — — — — — (a) No amounts were classified as investing cash flows from operating leases for the year ended December 31, 2020. (b) Does not include ROU assets recorded as a result of the adoption of the new lease standard. Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Cash paid for amounts included in the measurement of lease liabilities (a) Operating cash flows from operating leases $ 285 $ 34 $ 131 $ 53 $ 78 $ 2 $ 7 $ 7 Operating cash flows from finance leases 61 15 42 33 9 — 1 — Financing cash flows from finance leases 111 6 21 5 16 1 — — Lease assets obtained in exchange for new lease liabilities (non-cash) Operating (b) $ 194 $ 44 $ 30 $ 30 $ — $ — $ — $ 1 Finance 251 76 175 175 — — — — (a) No amounts were classified as investing cash flows from operating leases for the year ended December 31, 2019. (b) Does not include ROU assets recorded as a result of the adoption of the new lease standard. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Weighted average remaining lease term (years) Operating leases 10 9 10 12 8 17 18 5 Finance leases 13 19 15 17 11 — 25 — Weighted average discount rate (a) Operating leases 3.8 % 3.4 % 3.8 % 3.9 % 3.8 % 4.2 % 4.2 % 3.6 % Finance leases 8.4 % 11.6 % 11.9 % 12.4 % 8.2 % — % 11.9 % — % (a) The discount rate is calculated using the rate implicit in a lease if it is readily determinable. Generally, the rate used by the lessor is not provided to Duke Energy and in these cases the incremental borrowing rate is used. Duke Energy will typically use its fully collateralized incremental borrowing rate as of the commencement date to calculate and record the lease. The incremental borrowing rate is influenced by the lessee’s credit rating and lease term and as such may differ for individual leases, embedded leases or portfolios of leased assets. December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Weighted average remaining lease term (years) Operating leases 11 9 10 12 8 17 18 6 Finance leases 13 19 16 18 11 — 26 — Weighted average discount rate (a) Operating leases 3.9 % 3.5 % 3.8 % 3.9 % 3.8 % 4.2 % 4.1 % 3.6 % Finance leases 8.1 % 11.8 % 11.9 % 12.4 % 8.3 % — % 11.9 % — % (a) The discount rate is calculated using the rate implicit in a lease if it is readily determinable. Generally, the rate used by the lessor is not provided to Duke Energy and in these cases the incremental borrowing rate is used. Duke Energy will typically use its fully collateralized incremental borrowing rate as of the commencement date to calculate and record the lease. The incremental borrowing rate is influenced by the lessee’s credit rating and lease term and as such may differ for individual leases, embedded leases or portfolios of leased assets.

Debt and Credit Facilities

Debt and Credit Facilities	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Debt and Credit Facilities	DEBT AND CREDIT FACILITIES Summary of Debt and Related Terms The following tables summarize outstanding debt. December 31, 2020 Weighted Average Duke Duke Duke Duke Duke Interest Duke Energy Progress Energy Energy Energy Energy (in millions) Rate Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Unsecured debt, maturing 2021-2078 3.71 % $ 23,669 $ 1,150 $ 3,150 $ 700 $ 350 $ 1,180 $ 403 $ 2,800 Secured debt, maturing 2021-2052 2.67 % 4,270 543 1,584 252 1,332 — — — First mortgage bonds, maturing 2021-2050 (a) 4.00 % 29,177 10,008 14,100 7,875 6,225 1,850 3,219 — Finance leases, maturing 2022-2051 (b) 6.96 % 845 294 377 296 81 — 10 — Tax-exempt bonds, maturing 2027-2041 (c) 0.75 % 477 — 48 48 — 77 352 — Notes payable and commercial paper (d) 0.51 % 3,407 — — — — — — — Money pool/intercompany borrowings — 806 3,119 445 196 194 281 530 Fair value hedge carrying value adjustment 4 4 — — — — — — Unamortized debt discount and premium, net (e) 1,217 (20) (31) (19) (11) (29) (18) (5) Unamortized debt issuance costs (f) (330) (62) (113) (44) (62) (14) (25) (15) Total debt 3.62 % $ 62,736 $ 12,723 $ 22,234 $ 9,553 $ 8,111 $ 3,258 $ 4,222 $ 3,310 Short-term notes payable and commercial paper (2,873) — — — — — — — Short-term money pool/intercompany borrowings — (506) (2,969) (295) (196) (169) (131) (530) Current maturities of long-term debt (g) (4,238) (506) (1,426) (603) (823) (50) (70) (160) Total long-term debt (g) $ 55,625 $ 11,711 $ 17,839 $ 8,655 $ 7,092 $ 3,039 $ 4,021 $ 2,620 (a) Substantially all electric utility property is mortgaged under mortgage bond indentures. (b) Duke Energy includes $24 million and $341 million of finance lease purchase accounting adjustments related to Duke Energy Progress and Duke Energy Florida, respectively, related to PPAs that are not accounted for as finance leases in their respective financial statements because of grandfathering provisions in GAAP. (c) Substantially all tax-exempt bonds are secured by first mortgage bonds, letters of credit or the Master Credit Facility. (d) Includes $625 million classified as Long-Term Debt on the Consolidated Balance Sheets due to the existence of long-term credit facilities that backstop these commercial paper balances, along with Duke Energy’s ability and intent to refinance these balances on a long-term basis. The weighted average days to maturity for Duke Energy's commercial paper program was 23 days. (e) Duke Energy includes $1,196 million and $117 million in purchase accounting adjustments related to Progress Energy and Piedmont, respectively. (f) Duke Energy includes $33 million in purchase accounting adjustments primarily related to the merger with Progress Energy. (g) Refer to Note 17 for additional information on amounts from consolidated VIEs. December 31, 2019 Weighted Average Duke Duke Duke Duke Duke Interest Duke Energy Progress Energy Energy Energy Energy (in millions) Rate Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Unsecured debt, maturing 2020-2078 4.02 % $ 22,477 $ 1,150 $ 3,650 $ 700 $ 350 $ 1,110 $ 405 $ 2,399 Secured debt, maturing 2020-2052 3.30 % 4,537 544 1,722 335 1,387 — — — First mortgage bonds, maturing 2020-2049 (a) 4.13 % 27,977 9,557 13,800 7,575 6,225 1,449 3,169 — Finance leases, maturing 2022-2051 (b) 6.60 % 969 179 405 307 98 — 10 — Tax-exempt bonds, maturing 2022-2041 (c) 2.90 % 730 243 48 48 — 77 362 — Notes payable and commercial paper (d) 1.98 % 3,588 — — — — — — — Money pool/intercompany borrowings — 329 1,970 216 — 337 180 476 Fair value hedge carrying value adjustment 5 5 — — — — — — Unamortized debt discount and premium, net (e) 1,294 (23) (29) (17) (11) (30) (19) (2) Unamortized debt issuance costs (f) (316) (55) (111) (40) (62) (12) (20) (13) Total debt 3.92 % $ 61,261 $ 11,929 $ 21,455 $ 9,124 $ 7,987 $ 2,931 $ 4,087 $ 2,860 Short-term notes payable and commercial paper (3,135) — — — — — — — Short-term money pool/intercompany borrowings — (29) (1,821) (66) — (312) (30) (476) Current maturities of long-term debt (g) (3,141) (458) (1,577) (1,006) (571) — (503) — Total long-term debt (g) $ 54,985 $ 11,442 $ 18,057 $ 8,052 $ 7,416 $ 2,619 $ 3,554 $ 2,384 (a) Substantially all electric utility property is mortgaged under mortgage bond indentures. (b) Duke Energy includes $44 million and $419 million of finance lease purchase accounting adjustments related to Duke Energy Progress and Duke Energy Florida, respectively, related to PPAs that are not accounted for as finance leases in their respective financial statements because of grandfathering provisions in GAAP. (c) Substantially all tax-exempt bonds are secured by first mortgage bonds, letters of credit or the Master Credit Facility. (d) Includes $625 million that was classified as Long-Term Debt on the Consolidated Balance Sheets due to the existence of long-term credit facilities that backstop these commercial paper balances, along with Duke Energy’s ability and intent to refinance these balances on a long-term basis. The weighted average days to maturity for Duke Energy's commercial paper programs was 14 days. (e) Duke Energy includes $1,275 million and $137 million in purchase accounting adjustments related to Progress Energy and Piedmont, respectively. (f) Duke Energy includes $37 million in purchase accounting adjustments primarily related to the merger with Progress Energy. (g) Refer to Note 17 for additional information on amounts from consolidated VIEs. Current Maturities of Long-Term Debt The following table shows the significant components of Current maturities of Long-Term Debt on the Consolidated Balance Sheets. The Duke Energy Registrants currently anticipate satisfying these obligations with cash on hand and proceeds from additional borrowings. (in millions) Maturity Date Interest Rate December 31, 2020 Unsecured Debt (a) Duke Energy (Parent) May 2021 0.721 % (b) $ 500 Piedmont June 2021 4.240 % 160 Duke Energy (Parent) September 2021 3.550 % 500 Duke Energy (Parent) September 2021 1.800 % 750 Duke Energy Florida November 2021 0.482 % (b) 200 Secured Debt Duke Energy Florida April 2021 0.972 % (b) 250 First Mortgage Bonds Duke Energy Carolinas June 2021 3.900 % 500 Duke Energy Florida August 2021 3.100 % 300 Duke Energy Progress September 2021 3.000 % 500 Duke Energy Progress September 2021 8.625 % 100 Other (c) 478 Current maturities of long-term debt $ 4,238 (a) During October 2020, Progress Energy early retired $500 million of unsecured debt with an original maturity of January 15, 2021. (b) Debt has a floating interest rate. (c) Includes finance lease obligations, amortizing debt and small bullet maturities. Maturities and Call Options The following table shows the annual maturities of long-term debt for the next five years and thereafter. Amounts presented exclude short-term notes payable, commercial paper and money pool borrowings and debt issuance costs for the Subsidiary Registrants. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy (a) Carolinas Energy Progress Florida Ohio Indiana Piedmont 2021 $ 4,238 $ 506 $ 1,426 $ 603 $ 823 $ 50 $ 70 $ 160 2022 4,905 721 1,736 1,208 78 — 84 — 2023 3,356 1,008 638 561 77 325 3 45 2024 1,344 9 76 10 66 — 4 40 2025 3,153 310 725 661 64 270 154 205 Thereafter 41,983 9,745 14,802 6,274 6,878 2,486 3,818 2,350 Total long-term debt, including current maturities $ 58,979 $ 12,299 $ 19,403 $ 9,317 $ 7,986 $ 3,131 $ 4,133 $ 2,800 (a) Excludes $1,346 million in purchase accounting adjustments related to the Progress Energy merger and the Piedmont acquisition. The Duke Energy Registrants have the ability under certain debt facilities to call and repay the obligation prior to its scheduled maturity. Therefore, the actual timing of future cash repayments could be materially different than as presented above. Short-Term Obligations Classified as Long-Term Debt Tax-exempt bonds that may be put to the Duke Energy Registrants at the option of the holder and certain commercial paper issuances and money pool borrowings are classified as Long-Term Debt on the Consolidated Balance Sheets. These tax-exempt bonds, commercial paper issuances and money pool borrowings, which are short-term obligations by nature, are classified as long-term due to Duke Energy’s intent and ability to utilize such borrowings as long-term financing. As Duke Energy’s Master Credit Facility and other bilateral letter of credit agreements have non-cancelable terms in excess of one year as of the balance sheet date, Duke Energy has the ability to refinance these short-term obligations on a long-term basis. The following tables show short-term obligations classified as long-term debt. December 31, 2020 Duke Duke Duke Duke Duke Energy Energy Energy Energy (in millions) Energy Carolinas Progress Ohio Indiana Tax-exempt bonds $ 312 $ — $ — $ 27 $ 285 Commercial paper (a) 625 300 150 25 150 Total $ 937 $ 300 $ 150 $ 52 $ 435 December 31, 2019 Duke Duke Duke Duke Duke Energy Energy Energy Energy (in millions) Energy Carolinas Progress Ohio Indiana Tax-exempt bonds $ 312 $ — $ — $ 27 $ 285 Commercial paper (a) 625 300 150 25 150 Total $ 937 $ 300 $ 150 $ 52 $ 435 (a) Progress Energy amounts are equal to Duke Energy Progress amounts. Summary of Significant Debt Issuances The following tables summarize significant debt issuances (in millions). Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Maturity Interest Duke Energy Energy Energy Energy Energy Energy Issuance Date Date Rate Energy (Parent) Carolinas Progress Florida Ohio Indiana Piedmont Unsecured Debt May 2020 (a) Jun 2030 2.450 % $ 500 $ 500 $ — $ — $ — $ — $ — $ — May 2020 (b) Jun 2050 3.350 % 400 — — — — — — 400 August 2020 (c) Feb 2022 0.400 % (d) 700 — — 700 — — — — September 2020 (e) Sep 2025 0.900 % 650 650 — — — — — — September 2020 (e) Jun 2030 2.450 % 350 350 — — — — — — First Mortgage Bonds January 2020 (f) Feb 2030 2.450 % 500 — 500 — — — — — January 2020 (f) Aug 2049 3.200 % 400 — 400 — — — — — March 2020 (g) Apr 2050 2.750 % 550 — — — — — 550 — May 2020 (b) Jun 2030 2.125 % 400 — — — — 400 — — June 2020 (b) Jun 2030 1.750 % 500 — — — 500 — — — August 2020 (h) Aug 2050 2.500 % 600 — — 600 — — — — Total issuances $ 5,550 $ 1,500 $ 900 $ 1,300 $ 500 $ 400 $ 550 $ 400 (a) Debt issued to repay $500 million borrowing made under Duke Energy (Parent) revolving credit facility in March 2020, and for general corporate purposes. (b) Debt issued to repay short-term debt and for general corporate purposes. (c) Debt issued to repay $700 million term loan due December 2020. (d) Debt issuance has a floating interest rate. (e) Debt issued to repay a portion of outstanding commercial paper, to repay a portion of Duke Energy (Parent)'s outstanding $1.7 billion term loan due March 2021 and for general corporate purposes. (f) Debt issued to repay at maturity $450 million first mortgage bonds due June 2020 and for general corporate purposes. (g) Debt issued to repay at maturity $500 million first mortgage bonds due July 2020 and to pay down short-term debt. (h) Debt issued to repay at maturity $300 million first mortgage bonds due September 2020 and for general corporate purposes. Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Maturity Interest Duke Energy Energy Energy Energy Energy Energy Issuance Date Date Rate Energy (Parent) Carolinas Progress Florida Ohio Indiana Piedmont Unsecured Debt March 2019 (a) Mar 2022 2.538 % (b) $ 300 $ 300 $ — $ — $ — $ — $ — $ — March 2019 (a) Mar 2022 3.227 % 300 300 — — — — — — May 2019 (e) Jun 2029 3.500 % 600 — — — — — — 600 June 2019 (a) Jun 2029 3.400 % 600 600 — — — — — — June 2019 (a) Jun 2049 4.200 % 600 600 — — — — — — July 2019 (g) Jul 2049 4.320 % 40 — — — — 40 — — September 2019 (g) Oct 2025 3.230 % 95 — — — — 95 — — September 2019 (g) Oct 2029 3.560 % 75 — — — — 75 — — November 2019 (h) Nov 2021 2.167 % (b) 200 — — — 200 — — — First Mortgage Bonds January 2019 (c) Feb 2029 3.650 % 400 — — — — 400 — — January 2019 (c) Feb 2049 4.300 % 400 — — — — 400 — — March 2019 (d) Mar 2029 3.450 % 600 — — 600 — — — — August 2019 (a) Aug 2029 2.450 % 450 — 450 — — — — — August 2019 (a) Aug 2049 3.200 % 350 — 350 — — — — — September 2019 (f) Oct 2049 3.250 % 500 — — — — — 500 — November 2019 (i) Dec 2029 2.500 % 700 — — — 700 — — — Total issuances $ 6,210 $ 1,800 $ 800 $ 600 $ 900 $ 1,010 $ 500 $ 600 (a) Debt issued to pay down short-term debt and for general corporate purposes. (b) Debt issuance has a floating interest rate. (c) Debt issued to repay at maturity $450 million first mortgage bonds due April 2019, pay down short-term debt and for general corporate purposes. (d) Debt issued to fund eligible green energy projects in the Carolinas. (e) Debt issued to repay in full the outstanding $350 million Piedmont unsecured term loan due September 2019, pay down short-term debt and for general corporate purposes. (f) Debt issued to retire $150 million of pollution control bonds, pay down short-term debt and for general corporate purposes. (g) Debt issued to repay at maturity $100 million debentures due October 2019, pay down short-term debt and for general corporate purposes. (h) Debt issued to fund storm restoration costs and for general corporate purposes. (i) Debt issued to reimburse the payment of existing and new Eligible Green Expenditures in Florida. AVAILABLE CREDIT FACILITIES Master Credit Facility In March 2020, Duke Energy amended its existing $8 billion Master Credit Facility to extend the termination date to March 2025. The Duke Energy Registrants, excluding Progress Energy, have borrowing capacity under the Master Credit Facility up to a specified sublimit for each borrower. Duke Energy has the unilateral ability at any time to increase or decrease the borrowing sublimits of each borrower, subject to a maximum sublimit for each borrower. The amount available under the Master Credit Facility has been reduced to backstop issuances of commercial paper, certain letters of credit and variable-rate demand tax-exempt bonds that may be put to the Duke Energy Registrants at the option of the holder. The table below includes the current borrowing sublimits and available capacity under these credit facilities. December 31, 2020 Duke Duke Duke Duke Duke Duke Duke Energy Energy Energy Energy Energy Energy (in millions) Energy (Parent) Carolinas Progress Florida Ohio Indiana Piedmont Facility size (a) $ 8,000 $ 2,650 $ 1,475 $ 1,250 $ 800 $ 625 $ 600 $ 600 Reduction to backstop issuances Commercial paper (b) (2,239) — (736) (407) (179) (176) (257) (484) Outstanding letters of credit (40) (34) (4) (2) — — — — Tax-exempt bonds (81) — — — — — (81) — Available capacity $ 5,640 $ 2,616 $ 735 $ 841 $ 621 $ 449 $ 262 $ 116 (a) Represents the sublimit of each borrower. (b) Duke Energy issued $625 million of commercial paper and loaned the proceeds through the money pool to Duke Energy Carolinas, Duke Energy Progress, Duke Energy Ohio and Duke Energy Indiana. The balances are classified as Long-Term Debt Payable to Affiliated Companies in the Consolidated Balance Sheets. Term Loan Facility In response to market volatility and ongoing liquidity impacts from COVID-19, in March 2020, Duke Energy (Parent) entered into a $1.5 billion, 364-day Term Loan Credit Agreement, borrowing the full $1.5 billion available on March 19, 2020. The term loan contained a provision for increasing the amount available for borrowing by up to $500 million. Duke Energy (Parent) exercised this provision on March 27, 2020, borrowing an additional $188 million. Proceeds were used to reduce outstanding commercial paper and for general corporate purposes. The loan was repaid by Duke Energy (Parent) as of December 31, 2020. Refer to Note 1 for additional information on the COVID-19 pandemic. Three-Year Revolving Credit Facility Duke Energy (Parent) has a $1 billion revolving credit facility. The facility had an initial termination date of June 2020, but in May 2019, Duke Energy extended the termination date of the facility to May 2022. Borrowings under this facility will be used for general corporate purposes. As of December 31, 2020, $500 million has been drawn under this facility. This balance is classified as Long-term debt on Duke Energy's Consolidated Balance Sheets. Any undrawn commitments can be drawn, and borrowings can be prepaid, at any time throughout the term of the facility. During the first quarter of 2020, an additional $500 million was drawn under this facility to manage liquidity impacts from COVID-19. The additional $500 million was paid down during the second quarter of 2020. The terms and conditions of the facility are generally consistent with those governing Duke Energy's Master Credit Facility. Duke Energy Progress Term Loan Facility In December 2018, Duke Energy Progress entered into a two-year term loan facility with commitments totaling $700 million. Borrowings under the facility were used to pay storm-related costs, pay down commercial paper and to partially finance an upcoming bond maturity. As of December 31, 2019, the entire $700 million had been drawn under the term loan and was classified as Current maturities of long-term debt on Duke Energy Progress' Consolidated Balance Sheets. In August 2020, Duke Energy Progress repaid its $700 million two-year term loan facility. Other Debt Matters In September 2019, Duke Energy filed a Form S-3 with the SEC. Under this Form S-3, which is uncapped, the Duke Energy Registrants, excluding Progress Energy, may issue debt and other securities, including preferred stock, in the future at amounts, prices and with terms to be determined at the time of future offerings. The registration statement was filed to replace a similar prior filing upon expiration of its three-year term and also allows for the issuance of common and preferred stock by Duke Energy. Duke Energy has an effective Form S-3 with the SEC to sell up to $3 billion of variable denomination floating-rate demand notes, called PremierNotes. The Form S-3 states that no more than $1.5 billion of the notes will be outstanding at any particular time. The notes are offered on a continuous basis and bear interest at a floating rate per annum determined by the Duke Energy PremierNotes Committee, or its designee, on a weekly basis. The interest rate payable on notes held by an investor may vary based on the principal amount of the investment. The notes have no stated maturity date, are non-transferable and may be redeemed in whole or in part by Duke Energy or at the investor’s option at any time. The balance as of December 31, 2020, and 2019, was $1,168 million and $1,049 million, respectively. The notes are short-term debt obligations of Duke Energy and are reflected as Notes payable and commercial paper on Duke Energy’s Consolidated Balance Sheets. Money Pool The Subsidiary Registrants, excluding Progress Energy, are eligible to receive support for their short-term borrowing needs through participation with Duke Energy and certain of its subsidiaries in a money pool arrangement. Under this arrangement, those companies with short-term funds may provide short-term loans to affiliates participating in this arrangement. The money pool is structured such that the Subsidiary Registrants, excluding Progress Energy, separately manage their cash needs and working capital requirements. Accordingly, there is no net settlement of receivables and payables between money pool participants. Duke Energy (Parent), may loan funds to its participating subsidiaries, but may not borrow funds through the money pool. Accordingly, as the money pool activity is between Duke Energy and its wholly owned subsidiaries, all money pool balances are eliminated within Duke Energy’s Consolidated Balance Sheets. Money pool receivable balances are reflected within Notes receivable from affiliated companies on the Subsidiary Registrants’ Consolidated Balance Sheets. Money pool payable balances are reflected within either Notes payable to affiliated companies or Long-Term Debt Payable to Affiliated Companies on the Subsidiary Registrants’ Consolidated Balance Sheets. Restrictive Debt Covenants The Duke Energy Registrants’ debt and credit agreements contain various financial and other covenants. Duke Energy's Master Credit Facility contains a covenant requiring the debt-to-total capitalization ratio not to exceed 65% for each borrower, excluding Piedmont, and 70% for Piedmont. Failure to meet those covenants beyond applicable grace periods could result in accelerated due dates and/or termination of the agreements. As of December 31, 2020, each of the Duke Energy Registrants was in compliance with all covenants related to their debt agreements. In addition, some credit agreements may allow for acceleration of payments or termination of the agreements due to nonpayment, or acceleration of other significant indebtedness of the borrower or some of its subsidiaries. None of the debt or credit agreements contain material adverse change clauses. Other Loans As of December 31, 2020, and 2019, Duke Energy had loans outstanding of $817 million, including $35 million at Duke Energy Progress and $777 million, including $36 million at Duke Energy Progress, respectively, against the cash surrender value of life insurance policies it owns on the lives of its executives. The amounts outstanding were carried as a reduction of the related cash surrender value that is included in Other within Other Noncurrent Assets on the Consolidated Balance Sheets.

Guarantees and Indemnifications

Guarantees and Indemnifications	12 Months Ended
	Dec. 31, 2020
Guarantees [Abstract]
Guarantees and Indemnifications	GUARANTEES AND INDEMNIFICATIONS Duke Energy has various financial and performance guarantees and indemnifications with non-consolidated entities, which are issued in the normal course of business. As discussed below, these contracts include performance guarantees, standby letters of credit, debt guarantees and indemnifications. Duke Energy enters into these arrangements to facilitate commercial transactions with third parties by enhancing the value of the transaction to the third party. At December 31, 2020, Duke Energy does not believe conditions are likely for significant performance under these guarantees, except for ACP as described below. To the extent liabilities are incurred as a result of the activities covered by the guarantees, such liabilities are included on the accompanying Consolidated Balance Sheets. On January 2, 2007, Duke Energy completed the spin-off of its previously wholly owned natural gas businesses to shareholders. Guarantees issued by Duke Energy or its affiliates, or assigned to Duke Energy prior to the spin-off, remained with Duke Energy subsequent to the spin-off. Guarantees issued by Spectra Capital or its affiliates prior to the spin-off remained with Spectra Capital subsequent to the spin-off, except for guarantees that were later assigned to Duke Energy. Duke Energy has indemnified Spectra Capital against any losses incurred under certain of the guarantee obligations that remain with Spectra Capital. At December 31, 2020, the maximum potential amount of future payments associated with these guarantees were $56 million, the majority of which expires by 2028. In October 2017, ACP executed a $3.4 billion revolving credit facility with a stated maturity date of October 2021. Duke Energy entered into a guarantee agreement to support its share of the ACP revolving credit facility. In July 2020, ACP reduced the size of the credit facility to $1.9 billion. Duke Energy's maximum exposure to loss under the terms of the guarantee is $860 million as of December 31, 2020. This amount represents 47% of the outstanding borrowings under the credit facility. Duke Energy recognized the $860 million within Other Current Liabilities on the Consolidated Balance Sheets at December 31, 2020, of which $95 million was previously recognized due the adoption of new guidance for credit losses effective January 1, 2020. See Notes 3 and 12 for more information. The remaining reserve for credit losses for financial guarantees of $4 million at December 31, 2020, is included within Other Noncurrent Liabilities on the Duke Energy's Consolidated Balance Sheets. Management considers financial guarantees for evaluation under this standard based on the anticipated amount outstanding at the time of default. The reserve for credit losses is based on the evaluation of the contingent components of financial guarantees. Management evaluates the risk of default, exposure and length of time remaining in the period for each contract. In addition to the Spectra Capital and ACP revolving credit facility guarantees above, Duke Energy has issued performance guarantees to customers and other third parties that guarantee the payment and performance of other parties, including certain non-wholly owned entities, as well as guarantees of debt of certain non-consolidated entities. If such entities were to default on payments or performance, Duke Energy would be required under the guarantees to make payments on the obligations of these entities. The maximum potential amount of future payments required under these guarantees as of December 31, 2020, was $56 million of which $53 million expire between 2021 and 2030, with the remaining performance guarantees having no contractual expiration. Additionally, certain guarantees have uncapped maximum potential payments; however, Duke Energy does not believe these guarantees will have a material effect on its results of operations, cash flows or financial position. Duke Energy uses bank-issued standby letters of credit to secure the performance of wholly owned and non-wholly owned entities to a third party or customer. Under these arrangements, Duke Energy has payment obligations to the issuing bank that are triggered by a draw by the third party or customer due to the failure of the wholly owned or non-wholly owned entity to perform according to the terms of its underlying contract. At December 31, 2020, Duke Energy had issued a total of $566 million in letters of credit, which expire between 2021 and 2023. The unused amount under these letters of credit was $76 million.

Joint Ownership of Generating a

Joint Ownership of Generating and Transmission Facilities	12 Months Ended
	Dec. 31, 2020
Joint Ownership Of Generating And Transmission Facilities [Abstract]
Joint Ownership of Generating and Transmission Facilities	JOINT OWNERSHIP OF GENERATING AND TRANSMISSION FACILITIES The Duke Energy Registrants maintain ownership interests in certain jointly owned generating and transmission facilities. The Duke Energy Registrants are entitled to a share of the generating capacity and output of each unit equal to their respective ownership interests. The Duke Energy Registrants pay their ownership share of additional construction costs, fuel inventory purchases and operating expenses. The Duke Energy Registrants share of revenues and operating costs of the jointly owned facilities is included within the corresponding line in the Consolidated Statements of Operations. Each participant in the jointly owned facilities must provide its own financing. The following table presents the Duke Energy Registrants' interest of jointly owned plant or facilities and amounts included on the Consolidated Balance Sheets. All facilities are operated by the Duke Energy Registrants and are included in the Electric Utilities and Infrastructure segment. December 31, 2020 Construction Ownership Property, Plant Accumulated Work in (in millions except for ownership interest) Interest and Equipment Depreciation Progress Duke Energy Carolinas Catawba (units 1 and 2) (a) 19.25 % $ 1,017 $ 518 $ 23 W.S. Lee CC (b) 87.27 % 632 49 1 Duke Energy Indiana Gibson (unit 5) (c) 50.05 % 447 199 4 Vermillion (d) 62.50 % 174 101 1 Transmission and local facilities (c) Various 5,817 1,508 150 (a) Jointly owned with North Carolina Municipal Power Agency Number 1, NCEMC and PMPA. (b) Jointly owned with NCEMC. (c) Jointly owned with WVPA and IMPA. (d) Jointly owned with WVPA.

Asset Retirement Obligations

Asset Retirement Obligations	12 Months Ended
	Dec. 31, 2020
Asset Retirement Obligation Disclosure [Abstract]
Asset Retirement Obligations	ASSET RETIREMENT OBLIGATIONS Duke Energy records an ARO when it has a legal obligation to incur retirement costs associated with the retirement of a long-lived asset and the obligation can be reasonably estimated. Certain assets of the Duke Energy Registrants have an indeterminate life, such as transmission and distribution facilities, and thus the fair value of the retirement obligation is not reasonably estimable. A liability for these AROs will be recorded when a fair value is determinable. The Duke Energy Registrants’ regulated operations accrue costs of removal for property that does not have an associated legal retirement obligation based on regulatory orders from state commissions. These costs of removal are recorded as a regulatory liability in accordance with regulatory accounting treatment. The Duke Energy Registrants do not accrue the estimated cost of removal for any nonregulated assets. See Note 3 for the estimated cost of removal for assets without an associated legal retirement obligation, which are included in Regulatory liabilities on the Consolidated Balance Sheets. The following table presents the AROs recorded on the Consolidated Balance Sheets. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Decommissioning of nuclear power facilities (a) $ 6,845 $ 2,695 $ 4,101 $ 3,642 $ 459 $ — $ — $ — Closure of ash impoundments 5,778 2,597 1,973 1,950 23 67 1,140 — Other 381 58 75 43 32 44 36 20 Total asset retirement obligation $ 13,004 $ 5,350 $ 6,149 $ 5,635 $ 514 $ 111 $ 1,176 $ 20 Less: Current portion 718 264 283 283 — 3 168 — Total noncurrent asset retirement obligation $ 12,286 $ 5,086 $ 5,866 $ 5,352 $ 514 $ 108 $ 1,008 $ 20 (a) Duke Energy amount includes purchase accounting adjustments related to the merger with Progress Energy. Nuclear Decommissioning Liability AROs related to nuclear decommissioning are based on site-specific cost studies. The NCUC, PSCSC and FPSC require updated cost estimates for decommissioning nuclear plants every five years. The following table summarizes information about the most recent site-specific nuclear decommissioning cost studies. Decommissioning costs are stated in 2018 or 2019 dollars, depending on the year of the cost study, and include costs to decommission plant components not subject to radioactive contamination. Annual Funding Decommissioning (in millions) Requirement (a) Costs (a) Year of Cost Study Duke Energy $ 27 $ 9,105 2018 or 2019 Duke Energy Carolinas (b)(c) — 4,365 2018 Duke Energy Progress (d) 27 4,181 2019 Duke Energy Florida (e) — 559 N/A (a) Amounts for Progress Energy equal the sum of Duke Energy Progress and Duke Energy Florida. (b) Decommissioning cost for Duke Energy Carolinas reflects its ownership interest in jointly owned reactors. Other joint owners are responsible for decommissioning costs related to their interest in the reactors. (c) Duke Energy Carolinas' site-specific nuclear decommissioning cost study completed in 2018 was filed with the NCUC and PSCSC in 2019. A new funding study was also completed and filed with the NCUC and PSCSC in 2019. (d) Duke Energy Progress' site-specific nuclear decommissioning cost study completed in 2019 was filed with the NCUC and PSCSC in March 2020. Duke Energy Progress also completed a funding study, which was filed with the NCUC and PSCSC in July 2020. (e) During 2019, Duke Energy Florida reached an agreement to transfer decommissioning work for Crystal River Unit 3 to a third party and decommissioning costs are based on the agreement with this third party rather than a cost study. Regulatory approval was received from the NRC and the FPSC in April 2020 and August 2020, respectively. See Note 3 for more information. Nuclear Decommissioning Trust Funds Duke Energy Carolinas, Duke Energy Progress and Duke Energy Florida each maintain NDTFs that are intended to pay for the decommissioning costs of their respective nuclear power plants. The NDTF investments are managed and invested in accordance with applicable requirements of various regulatory bodies including the NRC, FERC, NCUC, PSCSC, FPSC and the IRS. Use of the NDTF investments is restricted to nuclear decommissioning activities including license termination, spent fuel and site restoration. The license termination and spent fuel obligations relate to contaminated decommissioning and are recorded as AROs. The site restoration obligation relates to non-contaminated decommissioning and is recorded to cost of removal within Regulatory liabilities on the Consolidated Balance Sheets. The following table presents the fair value of NDTF assets legally restricted for purposes of settling AROs associated with nuclear decommissioning. Duke Energy Florida entered into an agreement with a third party to decommission Crystal River Unit 3 and was granted an exemption from the NRC, which allows for use of the NDTF for all aspects of nuclear decommissioning. The entire balance of Duke Energy Florida's NDTF may be applied toward license termination, spent fuel and site restoration costs incurred to decommission Crystal River Unit 3 and is excluded from the table below. See Note 16 for additional information related to the fair value of the Duke Energy Registrants' NDTFs. December 31, (in millions) 2020 2019 Duke Energy $ 7,726 $ 6,766 Duke Energy Carolinas 4,381 3,837 Duke Energy Progress 3,345 2,929 Nuclear Operating Licenses Operating licenses for nuclear units are potentially subject to extension. The following table includes the current expiration of nuclear operating licenses. Unit Year of Expiration Duke Energy Carolinas Catawba Units 1 and 2 2043 McGuire Unit 1 2041 McGuire Unit 2 2043 Oconee Units 1 and 2 2033 Oconee Unit 3 2034 Duke Energy Progress Brunswick Unit 1 2036 Brunswick Unit 2 2034 Harris 2046 Robinson 2030 The NRC has acknowledged permanent cessation of operation and permanent removal of fuel from the reactor vessel at Crystal River Unit 3. Therefore, the license no longer authorizes operation of the reactor. During 2019, Duke Energy Florida entered into an agreement for the accelerated decommissioning of Crystal River Unit 3. Regulatory approval was received from the NRC and the FPSC in April 2020 and August 2020, respectively. See Note 3 for more information. Closure of Ash Impoundments The Duke Energy Registrants are subject to state and federal regulations covering the closure of coal ash impoundments, including the EPA CCR rule and the Coal Ash Act, and other agreements. AROs recorded on the Duke Energy Registrants' Consolidated Balance Sheets include the legal obligation for closure of coal ash basins and the disposal of related ash as a result of these regulations and agreements. The ARO amount recorded on the Consolidated Balance Sheets is based upon estimated closure costs for impacted ash impoundments. The amount recorded represents the discounted cash flows for estimated closure costs based upon specific closure plans. Actual costs to be incurred will be dependent upon factors that vary from site to site. The most significant factors are the method and time frame of closure at the individual sites. Closure methods considered include removing the water from ash basins, consolidating material as necessary and capping the ash with a synthetic barrier, excavating and relocating the ash to a lined structural fill or lined landfill or recycling the ash for concrete or some other beneficial use. The ultimate method and timetable for closure will be in compliance with standards set by federal and state regulations and other agreements. The ARO amount will be adjusted as additional information is gained through the closure and post-closure process, including acceptance and approval of compliance approaches, which may change management assumptions, and may result in a material change to the balance. See ARO Liability Rollforward section below for information on revisions made to the coal ash liability during 2020 and 2019. Asset retirement costs associated with the AROs for operating plants and retired plants are included in Net property, plant and equipment and Regulatory assets, respectively, on the Consolidated Balance Sheets. See Note 3 for additional information on Regulatory assets related to AROs. Cost recovery for future expenditures will be pursued through the normal ratemaking process with federal and state utility commissions, which permit recovery of necessary and prudently incurred costs associated with Duke Energy’s regulated operations. See Note 3 for additional information on recovery of coal ash costs. ARO Liability Rollforward The following tables present changes in the liability associated with AROs. Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Balance at December 31, 2018 $ 10,467 $ 3,949 $ 5,411 $ 4,820 $ 591 $ 93 $ 722 $ 19 Accretion expense (a) 508 235 252 227 25 3 28 1 Liabilities settled (b) (895) (329) (499) (460) (39) (12) (54) — Liabilities incurred in the current year 25 18 7 — 7 — — — Revisions in estimates of cash flows (c) 3,213 1,861 1,300 1,306 (6) (4) 136 (3) Balance at December 31, 2019 13,318 5,734 6,471 5,893 578 80 832 17 Accretion expense (a) 542 258 246 225 21 4 33 1 Liabilities settled (b) (724) (198) (451) (358) (93) (2) (74) — Liabilities incurred in the current year 22 — 5 — 5 — — — Revisions in estimates of cash flows (d) (154) (444) (122) (125) 3 29 385 2 Balance at December 31, 2020 $ 13,004 $ 5,350 $ 6,149 $ 5,635 $ 514 $ 111 $ 1,176 $ 20 (a) Substantially all accretion expense for the years ended December 31, 2020, and 2019, relates to Duke Energy’s regulated operations and has been deferred in accordance with regulatory accounting treatment. (b) Amounts primarily relate to ash impoundment closures and nuclear decommissioning. (c) Amounts primarily relate to increases in closure estimates for certain ash impoundments as a result of the NCDEQ's April 1, 2019, Order and the related settlement agreement dated December 31, 2019. (d) Primarily relates to decreases due to revised basin closure cost estimates, partially offset by increases related to new closure plan approvals, post closure maintenance and beneficiation costs. Duke Energy Indiana estimates also include the impacts of closure estimates for certain ash impoundments due to the impact of Hoosier Environmental Council’s petition filed with the court challenging the Indiana Department of Environmental Management’s partial approval of Duke Energy Indiana’s ash pond closure plan. See Note 4 for more information on Hoosier Environmental Council's petition. The incremental amount recorded represents the discounted cash flows for estimated closure costs based upon the probability weightings of the potential closure methods as evaluated on a site-by-site basis.

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	PROPERTY, PLANT AND EQUIPMENT The following tables summarize the property, plant and equipment for Duke Energy and its subsidiary registrants. December 31, 2020 Average Remaining Duke Duke Duke Duke Duke Useful Life Duke Energy Progress Energy Energy Energy Energy (in millions) (Years) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Land $ 2,046 $ 536 $ 908 $ 463 $ 445 $ 171 $ 118 $ 279 Plant – Regulated Electric generation, distribution and transmission 39 117,107 44,059 50,785 31,375 19,410 6,255 16,008 — Natural gas transmission and distribution 54 10,799 — — — — 3,136 — 7,663 Other buildings and improvements 36 2,038 740 459 197 262 374 300 165 Plant – Nonregulated Electric generation, distribution and transmission 27 5,444 — — — — — — — Other buildings and improvements 10 519 — — — — — — — Nuclear fuel 3,284 1,837 1,447 1,447 — — — — Equipment 15 2,608 620 759 498 261 385 238 122 Construction in process 6,645 1,645 2,013 709 1,304 407 409 581 Other 14 5,090 1,203 1,521 1,070 441 294 309 324 Total property, plant and equipment (a)(e) 155,580 50,640 57,892 35,759 22,123 11,022 17,382 9,134 Total accumulated depreciation – regulated (b)(c) (46,216) (17,453) (18,368) (12,801) (5,560) (3,013) (5,661) (1,749) Total accumulated depreciation – nonregulated (d)(e) (2,611) — — — — — — — Generation facilities to be retired, net 29 — 29 29 — — — — Total net property, plant and equipment $ 106,782 $ 33,187 $ 39,553 $ 22,987 $ 16,563 $ 8,009 $ 11,721 $ 7,385 (a) Includes finance leases of $832 million, $335 million, $416 million, $297 million, $119 million and $10 million at Duke Energy, Duke Energy Carolinas, Progress Energy, Duke Energy Progress, Duke Energy Florida and Duke Energy Indiana, respectively, primarily within Plant – Regulated. The Progress Energy, Duke Energy Progress and Duke Energy Florida amounts are net of $141 million, $24 million and $117 million, respectively, of accumulated amortization of finance leases. (b) Includes $1,832 million, $1,010 million, $822 million and $822 million of accumulated amortization of nuclear fuel at Duke Energy, Duke Energy Carolinas, Progress Energy and Duke Energy Progress, respectively. (c) Includes accumulated amortization of finance leases of $12 million, $23 million and $3 million at Duke Energy, Duke Energy Carolinas and Duke Energy Indiana, respectively. (d) Includes accumulated amortization of finance leases of $23 million at Duke Energy. (e) Includes gross property, plant and equipment cost of consolidated VIEs of $6,394 million and accumulated depreciation of consolidated VIEs of $1,242 million at Duke Energy. In 2020, Duke Energy evaluated recoverability of its renewable merchant plants principally located in the Electric Reliability Council of Texas West market and in the PJM West market due to declining market pricing and declining long-term forecasted energy prices, primarily driven by lower forecasted natural gas prices. Duke Energy determined that the assets were not impaired because the carrying value of $210 million approximates the aggregate estimated future undiscounted cash flows. A continued decline in energy market pricing would likely result in a future impairment. Duke Energy retained 51% ownership interest in these facilities following the 2019 transaction to sell a minority interest in certain renewable assets. See Note 1 for further information. December 31, 2019 Average Remaining Duke Duke Duke Duke Duke Useful Life Duke Energy Progress Energy Energy Energy Energy (in millions) (Years) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Land $ 2,091 $ 520 $ 884 $ 449 $ 435 $ 150 $ 117 $ 388 Plant – Regulated Electric generation, distribution and transmission 39 111,739 42,723 48,142 30,018 18,124 5,838 15,032 — Natural gas transmission and distribution 54 9,839 — — — — 2,892 — 6,947 Other buildings and improvements 32 1,810 714 401 162 239 269 278 148 Plant – Nonregulated Electric generation, distribution and transmission 28 5,103 — — — — — — — Other buildings and improvements 9 488 — — — — — — — Nuclear fuel 3,253 1,891 1,362 1,362 — — — — Equipment 13 2,313 546 665 452 213 319 205 128 Construction in process 6,102 1,389 2,149 1,114 1,035 504 381 531 Other 13 4,916 1,139 1,467 1,046 411 269 292 304 Total property, plant and equipment (a)(e) 147,654 48,922 55,070 34,603 20,457 10,241 16,305 8,446 Total accumulated depreciation – regulated (b)(c) (43,419) (16,525) (17,159) (11,915) (5,236) (2,843) (5,233) (1,681) Total accumulated depreciation – nonregulated (d)(e) (2,354) — — — — — — — Generation facilities to be retired, net 246 — 246 246 — — — — Total net property, plant and equipment $ 102,127 $ 32,397 $ 38,157 $ 22,934 $ 15,221 $ 7,398 $ 11,072 $ 6,765 (a) Includes finance leases of $952 million, $211 million, $443 million, $308 million, $135 million, and $10 million at Duke Energy, Duke Energy Carolinas, Progress Energy, Duke Energy Progress, Duke Energy Florida and Duke Energy Indiana, respectively, primarily within Plant – Regulated. The Progress Energy, Duke Energy Progress and Duke Energy Florida amounts are net of $143 million, $17 million and $126 million, respectively, of accumulated amortization of finance leases. (b) Includes $1,807 million, $1,082 million, $725 million and $725 million of accumulated amortization of nuclear fuel at Duke Energy, Duke Energy Carolinas, Progress Energy and Duke Energy Progress, respectively. (c) Includes accumulated amortization of finance leases of $6 million, $13 million, and $3 million at Duke Energy, Duke Energy Carolinas and Duke Energy Indiana, respectively. (d) Includes accumulated amortization of finance leases of $20 million at Duke Energy. (e) Includes gross property, plant and equipment cost of consolidated VIEs of $5,747 million and accumulated depreciation of consolidated VIEs of $1,041 million at Duke Energy. The following tables present capitalized interest, which includes the debt component of AFUDC. Years Ended December 31, (in millions) 2020 2019 2018 Duke Energy $ 112 $ 159 $ 161 Duke Energy Carolinas 28 30 35 Progress Energy 17 31 51 Duke Energy Progress 12 28 26 Duke Energy Florida 5 3 25 Duke Energy Ohio 26 22 17 Duke Energy Indiana 10 26 27 Piedmont 8 26 17

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	GOODWILL AND INTANGIBLE ASSETS GOODWILL Duke Energy The following table presents goodwill by reportable segment for Duke Energy included on Duke Energy's Consolidated Balance Sheets at December 31, 2020, and 2019. Electric Utilities Gas Utilities Commercial (in millions) and Infrastructure and Infrastructure Renewables Total Goodwill Balance at December 31, 2019 $ 17,379 $ 1,924 $ 122 $ 19,425 Accumulated impairment charges — — (122) (122) Goodwill balance at December 31, 2019, adjusted for accumulated impairment charges $ 17,379 $ 1,924 $ — $ 19,303 Goodwill Balance at December 31, 2020 $ 17,379 $ 1,924 $ 122 $ 19,425 Accumulated impairment charges — — (122) (122) Goodwill balance at December 31, 2020, adjusted for accumulated impairment charges $ 17,379 $ 1,924 $ — $ 19,303 (a) Duke Energy evaluated the recoverability of goodwill during 2018 and 2017 and recorded impairment charges of $93 million and $29 million, respectively, related to the Commercial Renewables reporting unit included in Impairment charges on Duke Energy's Consolidated Statements of Operations. The fair value of the reporting unit was determined based on the income approach and market approach in 2018 and 2017, respectively. See "Goodwill Impairment Testing" below for the results of the 2020 goodwill impairment test. Duke Energy Ohio Duke Energy Ohio's Goodwill balance of $920 million, allocated $596 million to Electric Utilities and Infrastructure and $324 million to Gas Utilities and Infrastructure, is presented net of accumulated impairment charges of $216 million on the Consolidated Balance Sheets at December 31, 2020, and 2019. Progress Energy Progress Energy's Goodwill is included in the Electric Utilities and Infrastructure segment and there are no accumulated impairment charges. Piedmont Piedmont's Goodwill is included in the Gas Utilities and Infrastructure segment and there are no accumulated impairment charges. Goodwill Impairment Testing Duke Energy, Progress Energy, Duke Energy Ohio and Piedmont are required to perform an annual goodwill impairment test as of the same date each year and, accordingly, perform their annual impairment testing of goodwill as of August 31. Duke Energy, Progress Energy, Duke Energy Ohio and Piedmont update their test between annual tests if events or circumstances occur that would more likely than not reduce the fair value of a reporting unit below its carrying value. As the fair value for Duke Energy, Progress Energy, Duke Energy Ohio and Piedmont exceeded their respective carrying values at the date of the annual impairment analysis, no goodwill impairment charges were recorded in 2020. INTANGIBLE ASSETS The following tables show the carrying amount and accumulated amortization of intangible assets included in Other within Other Noncurrent Assets on the Consolidated Balance Sheets of the Duke Energy Registrants at December 31, 2020, and 2019. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Emission allowances $ 8 $ — $ 5 $ 2 $ 3 $ — $ 2 $ — Renewable energy certificates 196 65 130 130 — 1 — — Natural gas, coal and power contracts 24 — — — — — 24 — Renewable operating and development projects 107 — — — — — — — Other 20 — — — — — — — Total gross carrying amounts 355 65 135 132 3 1 26 — Accumulated amortization – natural gas, coal and power contracts (23) — — — — — (23) — Accumulated amortization – renewable operating and development projects (34) — — — — — — — Accumulated amortization – other (3) — — — — — — — Total accumulated amortization (60) — — — — — (23) — Total intangible assets, net $ 295 $ 65 $ 135 $ 132 $ 3 $ 1 $ 3 $ — December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Emission allowances $ 18 $ — $ 5 $ 2 $ 3 $ — $ 12 $ — Renewable energy certificates 172 53 118 118 — 1 — — Natural gas, coal and power contracts 24 — — — — — 24 — Renewable operating and development projects 89 — — — — — — — Other 2 — — — — — — — Total gross carrying amounts 305 53 123 120 3 1 36 — Accumulated amortization – natural gas, coal and power contracts (21) — — — — — (21) — Accumulated amortization – renewable operating and development projects (34) — — — — — — — Accumulated amortization – other (1) — — — — — — — Total accumulated amortization (56) — — — — — (21) — Total intangible assets, net $ 249 $ 53 $ 123 $ 120 $ 3 $ 1 $ 15 $ — Amortization Expense Amortization expense amounts for natural gas, coal and power contracts, renewable operating projects and other intangible assets are immaterial for the years ended December 31, 2020, 2019 and 2018, and are expected to be immaterial for the next five years as of December 31, 2020.

Investments in Unconsolidated A

Investments in Unconsolidated Affiliates	12 Months Ended
	Dec. 31, 2020
Equity Method Investments and Joint Ventures [Abstract]
Investments in Unconsolidated Affiliates	INVESTMENTS IN UNCONSOLIDATED AFFILIATES EQUITY METHOD INVESTMENTS Investments in affiliates that are not controlled by Duke Energy, but over which it has significant influence, are accounted for using the equity method. The following table presents Duke Energy’s investments in unconsolidated affiliates accounted for under the equity method, as well as the respective equity in earnings, by segment. Years Ended December 31, 2020 2019 2018 Equity in Equity in Equity in (in millions) Investments earnings Investments earnings Investments earnings Electric Utilities and Infrastructure $ 105 $ (1) $ 122 $ 9 $ 97 $ 6 Gas Utilities and Infrastructure 215 (2,017) 1,388 114 1,003 27 Commercial Renewables 534 — 314 (4) 201 (1) Other 107 13 112 43 108 51 Total $ 961 $ (2,005) $ 1,936 $ 162 $ 1,409 $ 83 During the years ended December 31, 2020, 2019 and 2018, Duke Energy received distributions from equity investments of $37 million, $55 million and $108 million, respectively, which are included in Other assets within Cash Flows from Operating Activities on the Consolidated Statements of Cash Flows. During the years ended December 31, 2020, 2019 and 2018, Duke Energy received distributions from equity investments of $133 million, $11 million and $137 million, respectively, which are included in Return of investment capital within Cash Flows from Investing Activities on the Consolidated Statements of Cash Flows. During the years ended December 31, 2020, 2019 and 2018, Piedmont received distributions from equity investments of $2 million, $1 million and $1 million, respectively, which are included in Other assets within Cash Flows from Operating Activities and $2 million, $4 million and $3 million, respectively, which are included within Cash Flows from Investing Activities on the Consolidated Statements of Cash Flows. Significant investments in affiliates accounted for under the equity method are discussed below. Electric Utilities and Infrastructure Duke Energy owns 50% interests in both DATC and Pioneer, which build, own and operate electric transmission facilities in North America. Gas Utilities and Infrastructure The table below outlines Duke Energy's ownership interests in natural gas pipeline companies and natural gas storage facilities. Investment Amount (in millions) Ownership December 31, Entity Name Interest 2020 2019 Pipeline Investments (a) ACP (b) 47 % $ — $ 1,179 Sabal Trail 7.5 % 120 121 Cardinal (c) 21.49 % 9 9 Storage Facilities Pine Needle (c) 45 % 27 28 Hardy Storage (c) 50 % 56 51 Other 29.68 % 3 — Total Investments (d) $ 215 $ 1,388 (a) Duke Energy recorded OTTIs of $25 million and $55 million within Equity in (losses) earnings of unconsolidated affiliates on Duke Energy's Consolidated Statements of Operations for the years ended December 31, 2019, and 2018, respectively, to completely impair its 24% ownership interest in Constitution. (b) In 2020, Duke Energy determined it would no longer continue its investment in the construction of the ACP pipeline. See Notes 3 and 7 for further information. (c) Piedmont owns the Cardinal, Pine Needle and Hardy Storage investments. (d) Duke Energy includes purchase accounting adjustments related to Piedmont. Commercial Renewables DS Cornerstone, LLC, which owns wind farm projects in the U.S. was part of a sale of minority interest in a certain portion of renewable assets in 2019. See Note 1 for more information on the sale. Prior to the sale, Duke Energy had a 50% interest in DS Cornerstone, LLC. After the sale, Duke Energy has a 26% interest in the investment. As of December 31, 2020, Duke Energy completed its acquisition of 70 distributed fuel cell projects from Bloom Energy Corporation, which approximates 43 MW of capacity serving commercial and industrial customers across the U.S. Duke Energy is not the primary beneficiary of the distributed fuel cell portfolio and does not consolidate these assets. Other Duke Energy has a 17.5% indirect economic ownership interest and 25% board representation and voting rights interest in NMC, which owns and operates a methanol and MTBE business in Jubail, Saudi Arabia. Significant Subsidiaries For the year ended December 31, 2020, Duke Energy's investment in ACP met the requirements of S-X Rule 4-08(g) to provide summarized financial information. The following table provides summary information for ACP as required under S-X Rule 1-02(bb) for the comparative periods in Duke Energy's consolidated balance sheets and consolidated statements of operations. December 31, (in millions) 2020 2019 Current assets $ 43 $ 17 Noncurrent assets 93 4,091 Current liabilities 1,965 37 Noncurrent liabilities 167 1,760 Membership interests (1,996) 2,311 Years Ended December 31, 2020 2019 2018 Net revenues $ — $ — $ — Operating loss (4,612) (5) (6) Net (loss) income (4,512) 246 138 Net (loss) income attributable to Duke Energy $ (2,121) $ 116 $ 65

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2020
Related Party Transactions [Abstract]
Related Party Transactions	RELATED PARTY TRANSACTIONS The Subsidiary Registrants engage in related party transactions in accordance with the applicable state and federal commission regulations. Refer to the Consolidated Balance Sheets of the Subsidiary Registrants for balances due to or due from related parties. Material amounts related to transactions with related parties included in the Consolidated Statements of Operations and Comprehensive Income are presented in the following table. Years Ended December 31, (in millions) 2020 2019 2018 Duke Energy Carolinas Corporate governance and shared service expenses (a) $ 753 $ 841 $ 985 Indemnification coverages (b) 20 20 22 Joint Dispatch Agreement (JDA) revenue (c) 25 60 84 JDA expense (c) 114 186 207 Intercompany natural gas purchases (d) 15 15 15 Progress Energy Corporate governance and shared service expenses (a) $ 715 $ 778 $ 906 Indemnification coverages (b) 36 37 34 JDA revenue (c) 114 186 207 JDA expense (c) 25 60 84 Intercompany natural gas purchases (d) 75 76 78 Duke Energy Progress Corporate governance and shared service expenses (a) $ 420 $ 462 $ 577 Indemnification coverages (b) 17 15 13 JDA revenue (c) 114 186 207 JDA expense (c) 25 60 84 Intercompany natural gas purchases (d) 75 76 78 Duke Energy Florida Corporate governance and shared service expenses (a) $ 295 $ 316 $ 329 Indemnification coverages (b) 19 22 21 Duke Energy Ohio Corporate governance and shared service expenses (a) $ 326 $ 354 $ 374 Indemnification coverages (b) 4 4 5 Duke Energy Indiana Corporate governance and shared service expenses (a) $ 401 $ 412 $ 405 Indemnification coverages (b) 8 7 7 Piedmont Corporate governance and shared service expenses (a) $ 140 $ 138 $ 170 Indemnification coverages (b) 3 3 2 Intercompany natural gas sales (d) 90 91 93 Natural gas storage and transportation costs (e) 23 23 25 (a) The Subsidiary Registrants are charged their proportionate share of corporate governance and other shared services costs, primarily related to human resources, employee benefits, information technology, legal and accounting fees, as well as other third-party costs. These amounts are primarily recorded in Operation, maintenance and other on the Consolidated Statements of Operations and Comprehensive Income. (b) The Subsidiary Registrants incur expenses related to certain indemnification coverages through Bison, Duke Energy’s wholly owned captive insurance subsidiary. These expenses are recorded in Operation, maintenance and other on the Consolidated Statements of Operations and Comprehensive Income. (c) Duke Energy Carolinas and Duke Energy Progress participate in a JDA, which allows the collective dispatch of power plants between the service territories to reduce customer rates. Revenues from the sale of power and expenses from the purchase of power pursuant to the JDA are recorded in Operating Revenues and Fuel used in electric generation and purchased power, respectively, on the Consolidated Statements of Operations and Comprehensive Income. (d) Piedmont provides long-term natural gas delivery service to certain Duke Energy Carolinas and Duke Energy Progress natural gas-fired generation facilities. Piedmont records the sales in Operating Revenues, and Duke Energy Carolinas and Duke Energy Progress record the related purchases as a component of Fuel used in electric generation and purchased power on their respective Consolidated Statements of Operations and Comprehensive Income. These intercompany revenues and expenses are eliminated in consolidation. (e) Piedmont has related party transactions as a customer of its equity method investments in Pine Needle, Hardy Storage, and Cardinal natural gas storage and transportation facilities. These expenses are included in Cost of natural gas on Piedmont's Consolidated Statements of Operations and Comprehensive Income. In addition to the amounts presented above, the Subsidiary Registrants have other affiliate transactions, including rental of office space, participation in a money pool arrangement, other operational transactions and their proportionate share of certain charged expenses. See Note 6 for more information regarding money pool. These transactions of the Subsidiary Registrants are incurred in the ordinary course of business and are eliminated in consolidation. As discussed in Note 17, certain trade receivables have been sold by Duke Energy Ohio and Duke Energy Indiana to CRC, an affiliate formed by a subsidiary of Duke Energy. The proceeds obtained from the sales of receivables are largely cash but do include a subordinated note from CRC for a portion of the purchase price. Intercompany Income Taxes Duke Energy and the Subsidiary Registrants file a consolidated federal income tax return and other state and jurisdictional returns. The Subsidiary Registrants have a tax sharing agreement with Duke Energy for the allocation of consolidated tax liabilities and benefits. Income taxes recorded represent amounts the Subsidiary Registrants would incur as separate C-Corporations. The following table includes the balance of intercompany income tax receivables and payables for the Subsidiary Registrants. Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Carolinas Energy Progress Florida Ohio Indiana Piedmont December 31, 2020 Intercompany income tax receivable $ — $ — $ — $ — $ — $ 9 $ 10 Intercompany income tax payable 31 33 46 35 2 — — December 31, 2019 Intercompany income tax receivable $ — $ 125 $ 28 $ — $ 9 $ 28 $ 13 Intercompany income tax payable 5 — — 2 — — —

Derivatives and Hedging

Derivatives and Hedging	12 Months Ended
	Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives and Hedging	DERIVATIVES AND HEDGING The Duke Energy Registrants use commodity and interest rate contracts to manage commodity price risk and interest rate risk. The primary use of commodity derivatives is to hedge the generation portfolio against changes in the prices of electricity and natural gas. Piedmont enters into natural gas supply contracts to provide diversification, reliability and natural gas cost benefits to its customers. Interest rate derivatives are used to manage interest rate risk associated with borrowings. All derivative instruments not identified as NPNS are recorded at fair value as assets or liabilities on the Consolidated Balance Sheets. Cash collateral related to derivative instruments executed under master netting arrangements is offset against the collateralized derivatives on the Consolidated Balance Sheets. The cash impacts of settled derivatives are recorded as operating activities on the Consolidated Statements of Cash Flows. INTEREST RATE RISK The Duke Energy Registrants are exposed to changes in interest rates as a result of their issuance or anticipated issuance of variable-rate and fixed-rate debt and commercial paper. Interest rate risk is managed by limiting variable-rate exposures to a percentage of total debt and by monitoring changes in interest rates. To manage risk associated with changes in interest rates, the Duke Energy Registrants may enter into interest rate swaps, U.S. Treasury lock agreements and other financial contracts. In anticipation of certain fixed-rate debt issuances, a series of forward-starting interest rate swaps or Treasury locks may be executed to lock in components of current market interest rates. These instruments are later terminated prior to or upon the issuance of the corresponding debt. Cash Flow Hedges For a derivative designated as hedging the exposure to variable cash flows of a future transaction, referred to as a cash flow hedge, the effective portion of the derivative's gain or loss is initially reported as a component of other comprehensive income and subsequently reclassified into earnings once the future transaction impacts earnings. Amounts for interest rate contracts are reclassified to earnings as interest expense over the term of the related debt. Gains and losses reclassified out of AOCI for the years ended December 31, 2020, 2019 and 2018, were not material. Duke Energy's interest rate derivatives designated as hedges include interest rate swaps used to hedge existing debt within the Commercial Renewables segment and forward-starting interest rate swaps not accounted for under regulatory accounting. Undesignated Contracts Undesignated contracts primarily include contracts not designated as a hedge because they are accounted for under regulatory accounting or contracts that do not qualify for hedge accounting. Duke Energy’s interest rate swaps for its regulated operations employ regulatory accounting. With regulatory accounting, the mark-to-market gains or losses on the swaps are deferred as regulatory liabilities or regulatory assets, respectively. Regulatory assets and liabilities are amortized consistent with the treatment of the related costs in the ratemaking process. The accrual of interest on the swaps is recorded as Interest Expense on the Duke Energy Registrant's Consolidated Statements of Operations and Comprehensive Income. The following tables show notional amounts of outstanding derivatives related to interest rate risk. December 31, 2020 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Cash flow hedges $ 632 $ — $ — $ — $ — $ — Undesignated contracts 1,177 400 750 750 — 27 Total notional amount (a) $ 1,809 $ 400 $ 750 $ 750 $ — $ 27 December 31, 2019 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Cash flow hedges $ 993 $ — $ — $ — $ — $ — Undesignated contracts 1,277 450 800 250 550 27 Total notional amount (a) $ 2,270 $ 450 $ 800 $ 250 $ 550 $ 27 (a) Duke Energy includes amounts related to consolidated VIEs of $632 million in cash flow hedges as of December 31, 2020, and $693 million in cash flow hedges as of December 31, 2019. COMMODITY PRICE RISK The Duke Energy Registrants are exposed to the impact of changes in the prices of electricity purchased and sold in bulk power markets and natural gas purchases, including Piedmont's natural gas supply contracts. Exposure to commodity price risk is influenced by a number of factors including the term of contracts, the liquidity of markets and delivery locations. To manage risk associated with commodity prices, the Duke Energy Registrants may enter into long-term power purchase or sales contracts and long-term natural gas supply agreements. Cash Flow Hedges For derivatives designated as hedging the exposure to variable cash flows of a future transaction, referred to as a cash flow hedge, the derivative's gain or loss is initially reported as a component of other comprehensive income and subsequently reclassified into earnings once the future transaction impacts earnings. Gains and losses reclassified out of accumulated other comprehensive income (loss) for the year ended December 31, 2020 , 2019 and 2018, w ere not material. Duke Energy’s commodity derivatives designated as hedges include long-term electricity sales in the Commercial Renewables segment. Undesignated Contracts For the Subsidiary Registrants, bulk power electricity and natural gas purchases flow through fuel adjustment clauses, formula-based contracts or other cost sharing mechanisms. Differences between the costs included in rates and the incurred costs, including undesignated derivative contracts, are largely deferred as regulatory assets or regulatory liabilities. Piedmont policies allow for the use of financial instruments to hedge commodity price risks. The strategy and objective of these hedging programs are to use the financial instruments to reduce gas cost volatility for customers. Volumes The tables below include volumes of outstanding commodity derivatives. Amounts disclosed represent the absolute value of notional volumes of commodity contracts excluding NPNS. The Duke Energy Registrants have netted contractual amounts where offsetting purchase and sale contracts exist with identical delivery locations and times of delivery. Where all commodity positions are perfectly offset, no quantities are shown. December 31, 2020 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy Carolinas Energy Progress Ohio Indiana Piedmont Electricity (GWh) (a) 35,409 — — — 2,559 10,802 — Natural gas (millions of Dth) 678 145 158 158 — 2 373 December 31, 2019 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy Carolinas Energy Progress Ohio Indiana Piedmont Electricity (GWh) 15,858 — — — 1,887 13,971 — Natural gas (millions of Dth) 704 130 160 160 — 3 411 (a) Duke Energy includes 22,048 GWh that relates to cash flow hedges. LOCATION AND FAIR VALUE OF DERIVATIVE ASSETS AND LIABILITIES RECOGNIZED IN THE CONSOLIDATED BALANCE SHEETS The following tables show the fair value and balance sheet location of derivative instruments. Although derivatives subject to master netting arrangements are netted on the Consolidated Balance Sheets, the fair values presented below are shown gross and cash collateral on the derivatives has not been netted against the fair values shown. Derivative Assets December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Commodity Contracts Not Designated as Hedging Instruments Current $ 30 $ 14 $ 9 $ 9 $ — $ 1 $ 6 $ 1 Noncurrent 13 6 6 6 — — — — Total Derivative Assets – Commodity Contracts $ 43 $ 20 $ 15 $ 15 $ — $ 1 $ 6 $ 1 Interest Rate Contracts Not Designated as Hedging Instruments Current $ 18 $ — $ 18 $ 18 $ — $ — $ — $ — Total Derivative Assets – Interest Rate Contracts $ 18 $ — $ 18 $ 18 $ — $ — $ — $ — Total Derivative Assets $ 61 $ 20 $ 33 $ 33 $ — $ 1 $ 6 $ 1 Derivative Liabilities December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Commodity Contracts Designated as Hedging Instruments Current $ 14 $ — $ — $ — $ — $ — $ — $ — Noncurrent 70 — — — — — — — Not Designated as Hedging Instruments Current $ 30 $ 13 $ 2 $ 2 $ — $ — $ 1 $ 15 Noncurrent 137 3 27 12 — — — 107 Total Derivative Liabilities – Commodity Contracts $ 251 $ 16 $ 29 $ 14 $ — $ — $ 1 $ 122 Interest Rate Contracts Designated as Hedging Instruments Current $ 15 $ — $ — $ — $ — $ — $ — $ — Noncurrent 48 — — — — — — — Not Designated as Hedging Instruments Current 5 4 — — — 1 — — Noncurrent 5 — — — — 5 — — Total Derivative Liabilities – Interest Rate Contracts $ 73 $ 4 $ — $ — $ — $ 6 $ — $ — Total Derivative Liabilities $ 324 $ 20 $ 29 $ 14 $ — $ 6 $ 1 $ 122 Derivative Assets December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Commodity Contracts Not Designated as Hedging Instruments Current $ 17 $ — $ — $ — $ — $ 3 $ 13 $ 1 Noncurrent 1 — — — — 1 — — Total Derivative Assets – Commodity Contracts $ 18 $ — $ — $ — $ — $ 4 $ 13 $ 1 Interest Rate Contracts Not Designated as Hedging Instruments Current 6 — 6 — 6 — — — Total Derivative Assets – Interest Rate Contracts $ 6 $ — $ 6 $ — $ 6 $ — $ — $ — Equity Securities Contracts Not Designated as Hedging Instruments Current $ 1 $ — $ 1 $ — $ 1 $ — $ — $ — Total Derivative Assets – Equity Securities Contracts $ 1 $ — $ 1 $ — $ 1 $ — $ — $ — Total Derivative Assets $ 25 $ — $ 7 $ — $ 7 $ 4 $ 13 $ 1 Derivative Liabilities December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Commodity Contracts Not Designated as Hedging Instruments Current $ 67 $ 33 $ 26 $ 26 $ — $ — $ 1 $ 7 Noncurrent 156 10 37 22 — — — 110 Total Derivative Liabilities – Commodity Contracts $ 223 $ 43 $ 63 $ 48 $ — $ — $ 1 $ 117 Interest Rate Contracts Designated as Hedging Instruments Current $ 19 $ — $ — $ — $ — $ — $ — $ — Noncurrent 21 — — — — — — — Not Designated as Hedging Instruments Current 8 6 1 1 — 1 — — Noncurrent 5 — — — — 5 — — Total Derivative Liabilities – Interest Rate Contracts $ 53 $ 6 $ 1 $ 1 $ — $ 6 $ — $ — Equity Securities Contracts Not Designated as Hedging Instruments Current $ 24 $ — $ 24 $ — $ 24 $ — $ — $ — Total Derivative Liabilities – Equity Securities Contracts $ 24 $ — $ 24 $ — $ 24 $ — $ — $ — Total Derivative Liabilities $ 300 $ 49 $ 88 $ 49 $ 24 $ 6 $ 1 $ 117 OFFSETTING ASSETS AND LIABILITIES The following tables present the line items on the Consolidated Balance Sheets where derivatives are reported. Substantially all of Duke Energy's outstanding derivative contracts are subject to enforceable master netting arrangements. The gross amounts offset in the tables below show the effect of these netting arrangements on financial position and include collateral posted to offset the net position. The amounts shown are calculated by counterparty. Accounts receivable or accounts payable may also be available to offset exposures in the event of bankruptcy. These amounts are not included in the tables below. Derivative Assets December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Current Gross amounts recognized $ 48 $ 14 $ 27 $ 27 $ — $ 1 $ 6 $ 1 Gross amounts offset (3) (2) (2) (2) — — — — Net amounts presented in Current Assets: Other $ 45 $ 12 $ 25 $ 25 $ — $ 1 $ 6 $ 1 Noncurrent Gross amounts recognized $ 13 $ 6 $ 6 $ 6 $ — $ — $ — $ — Gross amounts offset (5) (1) (4) (4) — — — — Net amounts presented in Other Noncurrent Assets: Other $ 8 $ 5 $ 2 $ 2 $ — $ — $ — $ — Derivative Liabilities December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Current Gross amounts recognized $ 64 $ 17 $ 2 $ 2 $ — $ 1 $ 1 $ 15 Gross amounts offset (3) (2) (2) (2) — — — — Net amounts presented in Current Liabilities: Other $ 61 $ 15 $ — $ — $ — $ 1 $ 1 $ 15 Noncurrent Gross amounts recognized $ 260 $ 3 $ 27 $ 12 $ — $ 5 $ — $ 107 Gross amounts offset (5) (1) (4) (4) — — — — Net amounts presented in Other Noncurrent Liabilities: Other $ 255 $ 2 $ 23 $ 8 $ — $ 5 $ — $ 107 Derivative Assets December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Current Gross amounts recognized $ 24 $ — $ 7 $ — $ 7 $ 3 $ 13 $ 1 Gross amounts offset (1) — (1) — (1) — — — Net amounts presented in Current Assets: Other $ 23 $ — $ 6 $ — $ 6 $ 3 $ 13 $ 1 Noncurrent Gross amounts recognized $ 1 $ — $ — $ — $ — $ 1 $ — $ — Gross amounts offset — — — — — — — — Net amounts presented in Other Noncurrent Assets: Other $ 1 $ — $ — $ — $ — $ 1 $ — $ — Derivative Liabilities December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Current Gross amounts recognized $ 118 $ 39 $ 51 $ 27 $ 24 $ 1 $ 1 $ 7 Gross amounts offset (24) — (24) — (24) — — — Net amounts presented in Current Liabilities: Other $ 94 $ 39 $ 27 $ 27 $ — $ 1 $ 1 $ 7 Noncurrent Gross amounts recognized $ 182 $ 10 $ 37 $ 22 $ — $ 5 $ — $ 110 Gross amounts offset — — — — — — — — Net amounts presented in Other Noncurrent Liabilities: Other $ 182 $ 10 $ 37 $ 22 $ — $ 5 $ — $ 110 OBJECTIVE CREDIT CONTINGENT FEATURES Certain derivative contracts contain objective credit contingent features. These features include the requirement to post cash collateral or letters of credit if specific events occur, such as a credit rating downgrade below investment grade. The following tables show information with respect to derivative contracts that are in a net liability position and contain objective credit-risk-related payment provisions. December 31, 2020 Duke Duke Duke Energy Progress Energy (in millions) Energy Carolinas Energy Progress Aggregate fair value of derivatives in a net liability position $ 24 $ 9 $ 14 $ 14 Fair value of collateral already posted — — — — Additional cash collateral or letters of credit in the event credit-risk-related contingent features were triggered 24 9 14 14 December 31, 2019 Duke Duke Duke Energy Progress Energy (in millions) Energy Carolinas Energy Progress Aggregate fair value of derivatives in a net liability position $ 79 $ 35 $ 44 $ 44 Fair value of collateral already posted — — — — Additional cash collateral or letters of credit in the event credit-risk-related contingent features were triggered 79 35 44 44 The Duke Energy Registrants have elected to offset cash collateral and fair values of derivatives. For amounts to be netted, the derivative and cash collateral must be executed with the same counterparty under the same master netting arrangement.

Investments in Debt and Equity

Investments in Debt and Equity Securities	12 Months Ended
	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Investments in Debt and Equity Securities	INVESTMENTS IN DEBT AND EQUITY SECURITIES Duke Energy’s investments in debt and equity securities are primarily comprised of investments held in (i) the NDTF at Duke Energy Carolinas, Duke Energy Progress and Duke Energy Florida, (ii) the grantor trusts at Duke Energy Progress, Duke Energy Florida and Duke Energy Indiana related to OPEB plans and (iii) Bison. The Duke Energy Registrants classify investments in debt securities as AFS and investments in equity securities as FV-NI. For investments in debt securities classified as AFS, the unrealized gains and losses are included in other comprehensive income until realized, at which time they are reported through net income. For investments in equity securities classified as FV-NI, both realized and unrealized gains and losses are reported through net income. Substantially all of Duke Energy’s investments in debt and equity securities qualify for regulatory accounting, and accordingly, all associated realized and unrealized gains and losses on these investments are deferred as a regulatory asset or liability. Duke Energy classifies the majority of investments in debt and equity securities as long term, unless otherwise noted. Investment Trusts The investments within the Investment Trusts are managed by independent investment managers with discretion to buy, sell and invest pursuant to the objectives set forth by the investment manager agreements and trust agreements. The Duke Energy Registrants have limited oversight of the day-to-day management of these investments. As a result, the ability to hold investments in unrealized loss positions is outside the control of the Duke Energy Registrants. Accordingly, all unrealized losses associated with debt securities within the Investment Trusts are recognized immediately and deferred to regulatory accounts where appropriate. Other AFS Securities Unrealized gains and losses on all other AFS securities are included in other comprehensive income until realized, unless it is determined the carrying value of an investment has a credit loss. The Duke Energy Registrants analyze all investment holdings each reporting period to determine whether a decline in fair value is related to a credit loss. If a credit loss exists, the unrealized credit loss is included in earnings. There were no material credit losses as of December 31, 2020, and 2019. Other Investments amounts are recorded in Other within Other Noncurrent Assets on the Consolidated Balance Sheets. DUKE ENERGY The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS. December 31, 2020 December 31, 2019 Gross Gross Gross Gross Unrealized Unrealized Unrealized Unrealized Holding Holding Estimated Holding Holding Estimated (in millions) Gains Losses Fair Value Gains Losses Fair Value NDTF Cash and cash equivalents $ — $ — $ 177 $ — $ — $ 101 Equity securities 4,138 54 6,235 3,523 55 5,661 Corporate debt securities 76 1 806 37 1 603 Municipal bonds 22 — 370 13 — 368 U.S. government bonds 51 — 1,361 33 1 1,256 Other debt securities 8 — 180 3 — 141 Total NDTF Investments $ 4,295 $ 55 $ 9,129 $ 3,609 $ 57 $ 8,130 Other Investments Cash and cash equivalents $ — $ — $ 127 $ — $ — $ 52 Equity securities 79 — 146 57 — 122 Corporate debt securities 8 — 110 3 — 67 Municipal bonds 5 — 86 4 — 94 U.S. government bonds — — 42 2 — 41 Other debt securities — — 47 — — 56 Total Other Investments $ 92 $ — $ 558 $ 66 $ — $ 432 Total Investments $ 4,387 $ 55 $ 9,687 $ 3,675 $ 57 $ 8,562 The table below summarizes the maturity date for debt securities. (in millions) December 31, 2020 Due in one year or less $ 149 Due after one through five years 922 Due after five through 10 years 671 Due after 10 years 1,260 Total $ 3,002 Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the years ended December 31, 2020, 2019 and 2018, were as follows. Years Ended December 31, (in millions) 2020 2019 2018 FV-NI: Realized gains $ 366 $ 172 $ 168 Realized losses 174 151 126 AFS: Realized gains 96 94 22 Realized losses 51 67 51 DUKE ENERGY CAROLINAS The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS. December 31, 2020 December 31, 2019 Gross Gross Gross Gross Unrealized Unrealized Unrealized Unrealized Holding Holding Estimated Holding Holding Estimated (in millions) Gains Losses Fair Value Gains Losses Fair Value NDTF Cash and cash equivalents $ — $ — $ 30 $ — $ — $ 21 Equity securities 2,442 23 3,685 1,914 8 3,154 Corporate debt securities 49 1 510 21 1 361 Municipal bonds 6 — 91 3 — 96 U.S. government bonds 25 — 475 16 1 578 Other debt securities 7 — 174 3 — 137 Total NDTF Investments $ 2,529 $ 24 $ 4,965 $ 1,957 $ 10 $ 4,347 The table below summarizes the maturity date for debt securities. (in millions) December 31, 2020 Due in one year or less $ 14 Due after one through five years 299 Due after five through 10 years 279 Due after 10 years 658 Total $ 1,250 Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the years ended December 31, 2020, 2019 and 2018, were as follows. Years Ended December 31, (in millions) 2020 2019 2018 FV-NI: Realized gains $ 64 $ 113 $ 89 Realized losses 99 107 73 AFS: Realized gains 60 55 19 Realized losses 37 38 35 PROGRESS ENERGY The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS. December 31, 2020 December 31, 2019 Gross Gross Gross Gross Unrealized Unrealized Unrealized Unrealized Holding Holding Estimated Holding Holding Estimated (in millions) Gains Losses Fair Value Gains Losses Fair Value NDTF Cash and cash equivalents $ — $ — $ 147 $ — $ — $ 80 Equity securities 1,696 31 2,550 1,609 47 2,507 Corporate debt securities 27 — 296 16 — 242 Municipal bonds 16 — 279 10 — 272 U.S. government bonds 26 — 886 17 — 678 Other debt securities 1 — 6 — — 4 Total NDTF Investments $ 1,766 $ 31 $ 4,164 $ 1,652 $ 47 $ 3,783 Other Investments Cash and cash equivalents $ — $ — $ 106 $ — $ — $ 49 Municipal bonds 3 — 26 3 — 51 Total Other Investments $ 3 $ — $ 132 $ 3 $ — $ 100 Total Investments $ 1,769 $ 31 $ 4,296 $ 1,655 $ 47 $ 3,883 The table below summarizes the maturity date for debt securities. (in millions) December 31, 2020 Due in one year or less $ 109 Due after one through five years 567 Due after five through 10 years 298 Due after 10 years 519 Total $ 1,493 Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the years ended December 31, 2020, 2019 and 2018, were as follows. Years Ended December 31, (in millions) 2020 2019 2018 FV-NI: Realized gains $ 302 $ 59 $ 79 Realized losses 75 44 53 AFS: Realized gains 24 36 3 Realized losses 13 29 15 DUKE ENERGY PROGRESS The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS. December 31, 2020 December 31, 2019 Gross Gross Gross Gross Unrealized Unrealized Unrealized Unrealized Holding Holding Estimated Holding Holding Estimated (in millions) Gains Losses Fair Value Gains Losses Fair Value NDTF Cash and cash equivalents $ — $ — $ 76 $ — $ — $ 53 Equity securities 1,617 31 2,459 1,258 21 2,077 Corporate debt securities 27 — 296 16 — 242 Municipal bonds 16 — 279 10 — 272 U.S. government bonds 26 — 412 16 — 403 Other debt securities 1 — 6 — — 4 Total NDTF Investments $ 1,687 $ 31 $ 3,528 $ 1,300 $ 21 $ 3,051 Other Investments Cash and cash equivalents $ — $ — $ 1 $ — $ — $ 2 Total Other Investments $ — $ — $ 1 $ — $ — $ 2 Total Investments $ 1,687 $ 31 $ 3,529 $ 1,300 $ 21 $ 3,053 The table below summarizes the maturity date for debt securities. (in millions) December 31, 2020 Due in one year or less $ 21 Due after one through five years 259 Due after five through 10 years 210 Due after 10 years 503 Total $ 993 Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the years ended December 31, 2020, 2019 and 2018, were as follows. Years Ended December 31, (in millions) 2020 2019 2018 FV-NI: Realized gains $ 52 $ 38 $ 68 Realized losses 59 33 48 AFS: Realized gains 24 7 2 Realized losses 13 5 10 DUKE ENERGY FLORIDA The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS. December 31, 2020 December 31, 2019 Gross Gross Gross Gross Unrealized Unrealized Unrealized Unrealized Holding Holding Estimated Holding Holding Estimated (in millions) Gains Losses Fair Value Gains Losses Fair Value NDTF Cash and cash equivalents $ — $ — $ 71 $ — $ — $ 27 Equity securities 79 — 91 351 26 430 U.S. government bonds — — 474 1 — 275 Total NDTF Investments (a) $ 79 $ — $ 636 $ 352 $ 26 $ 732 Other Investments Cash and cash equivalents $ — $ — $ 1 $ — $ — $ 4 Municipal bonds 3 — 26 3 — 51 Total Other Investments $ 3 $ — $ 27 $ 3 $ — $ 55 Total Investments $ 82 $ — $ 663 $ 355 $ 26 $ 787 (a) During the years ended December 31, 2020, and 2019, Duke Energy Florida continued to receive reimbursements from the NDTF for costs related to ongoing decommissioning activity of the Crystal River Unit 3. The table below summarizes the maturity date for debt securities. (in millions) December 31, 2020 Due in one year or less $ 88 Due after one through five years 308 Due after five through 10 years 88 Due after 10 years 16 Total $ 500 Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the years ended December 31, 2020, 2019 and 2018, were as follows. Years Ended December 31, (in millions) 2020 2019 2018 FV-NI: Realized gains $ 250 $ 21 $ 11 Realized losses 16 11 5 AFS: Realized gains — 29 1 Realized losses — 24 5 DUKE ENERGY INDIANA The following table presents the estimated fair value of investments in debt and equity securities; equity investments are measured at FV-NI and debt investments are classified as AFS. December 31, 2020 December 31, 2019 Gross Gross Gross Gross Unrealized Unrealized Unrealized Unrealized Holding Holding Estimated Holding Holding Estimated (in millions) Gains Losses Fair Value Gains Losses Fair Value Investments Cash and cash equivalents $ — $ — $ 1 $ — $ — $ — Equity securities 58 — 97 43 — 81 Corporate debt securities — — 3 — — 6 Municipal bonds 1 — 38 1 — 36 U.S. government bonds — — 4 — — 2 Total Investments $ 59 $ — $ 143 $ 44 $ — $ 125 The table below summarizes the maturity date for debt securities. (in millions) December 31, 2020 Due in one year or less $ 3 Due after one through five years 17 Due after five through 10 years 10 Due after 10 years 15 Total $ 45 Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the years ended December 31, 2020, 2019 and 2018, were immaterial.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	FAIR VALUE MEASUREMENTS Fair value is the exchange price to sell an asset or transfer a liability in an orderly transaction between market participants at the measurement date. The fair value definition focuses on an exit price versus the acquisition cost. Fair value measurements use market data or assumptions market participants would use in pricing the asset or liability, including assumptions about risk and the risks inherent in the inputs to the valuation technique. These inputs may be readily observable, corroborated by market data, or generally unobservable. Valuation techniques maximize the use of observable inputs and minimize use of unobservable inputs. A midmarket pricing convention (the midpoint price between bid and ask prices) is permitted for use as a practical expedient. Fair value measurements are classified in three levels based on the fair value hierarchy as defined by GAAP. Certain investments are not categorized within the fair value hierarchy. These investments are measured at fair value using the net asset value per share practical expedient. The net asset value is derived based on the investment cost, less any impairment, plus or minus changes resulting from observable price changes for an identical or similar investment of the same issuer. Fair value accounting guidance permits entities to elect to measure certain financial instruments that are not required to be accounted for at fair value, such as equity method investments or the company’s own debt, at fair value. The Duke Energy Registrants have not elected to record any of these items at fair value. Valuation methods of the primary fair value measurements disclosed below are as follows. Investments in equity securities The majority of investments in equity securities are valued using Level 1 measurements. Investments in equity securities are typically valued at the closing price in the principal active market as of the last business day of the quarter. Principal active markets for equity prices include published exchanges such as the NYSE and Nasdaq Stock Market. Foreign equity prices are translated from their trading currency using the currency exchange rate in effect at the close of the principal active market. There was no after-hours market activity that was required to be reflected in the reported fair value measurements. Investments in debt securities Most investments in debt securities are valued using Level 2 measurements because the valuations use interest rate curves and credit spreads applied to the terms of the debt instrument (maturity and coupon interest rate) and consider the counterparty credit rating. If the market for a particular fixed-income security is relatively inactive or illiquid, the measurement is Level 3. Commodity derivatives Commodity derivatives with clearinghouses are classified as Level 1. Commodity derivatives with observable forward curves are classified as Level 2. If forward price curves are not observable for the full term of the contract and the unobservable period had more than an insignificant impact on the valuation, the commodity derivative is classified as Level 3. In isolation, increases (decreases) in natural gas forward prices result in favorable (unfavorable) fair value adjustments for natural gas purchase contracts; and increases (decreases) in electricity forward prices result in unfavorable (favorable) fair value adjustments for electricity sales contracts. Duke Energy regularly evaluates and validates pricing inputs used to estimate the fair value of natural gas commodity contracts by a market participant price verification procedure. This procedure provides a comparison of internal forward commodity curves to market participant generated curves. Interest rate derivatives Most over-the-counter interest rate contract derivatives are valued using financial models that utilize observable inputs for similar instruments and are classified as Level 2. Inputs include forward interest rate curves, notional amounts, interest rates and credit quality of the counterparties. Other fair value considerations See Note 11 for a discussion of the valuation of goodwill and intangible assets. DUKE ENERGY The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Consolidated Balance Sheets. Derivative amounts in the tables below for all Duke Energy Registrants exclude cash collateral, which is disclosed in Note 14. See Note 15 for additional information related to investments by major security type for the Duke Energy Registrants. December 31, 2020 (in millions) Total Fair Value Level 1 Level 2 Level 3 Not Categorized NDTF cash and cash equivalents $ 177 $ 177 $ — $ — $ — NDTF equity securities 6,235 6,189 — — 46 NDTF debt securities 2,717 874 1,843 — — Other equity securities 146 146 — — — Other debt securities 285 37 248 — — Other cash and cash equivalents 127 127 — — — Derivative assets 61 1 53 7 — Total assets 9,748 7,551 2,144 7 46 Derivative liabilities (324) — (240) (84) — Net assets (liabilities) $ 9,424 $ 7,551 $ 1,904 $ (77) $ 46 December 31, 2019 (in millions) Total Fair Value Level 1 Level 2 Level 3 Not Categorized NDTF cash and cash equivalents $ 101 $ 101 $ — $ — $ — NDTF equity securities 5,684 5,633 — — 51 NDTF debt securities 2,368 725 1,643 — — Other equity securities 122 122 — — — Other debt securities 258 39 219 — — Other cash and cash equivalents 52 52 — — — Derivative assets 25 3 7 15 — Total assets 8,610 6,675 1,869 15 51 NDTF equity security contracts (23) — (23) — — Derivative liabilities (277) (15) (145) (117) — Net assets (liabilities) $ 8,310 $ 6,660 $ 1,701 $ (102) $ 51 The following table provides reconciliations of beginning and ending balances of assets and liabilities measured at fair value using Level 3 measurements. Derivatives (net) Years Ended December 31, (in millions) 2020 2019 Balance at beginning of period $ (102) $ (113) Total pretax realized or unrealized losses included in comprehensive income (84) — Purchases, sales, issuances and settlements: Purchases 14 37 Settlements (19) (44) Net transfers Out of Level 3 (a) 117 — Total (losses) gains included on the Consolidated Balance Sheet (3) 18 Balance at end of period $ (77) $ (102) (a) Transferred from Level 3 to Level 2 because observable market data became available. DUKE ENERGY CAROLINAS The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Consolidated Balance Sheets. December 31, 2020 (in millions) Total Fair Value Level 1 Level 2 Not Categorized NDTF cash and cash equivalents $ 30 $ 30 $ — $ — NDTF equity securities 3,685 3,639 — 46 NDTF debt securities 1,250 192 1,058 — Derivative assets 20 — 20 — Total assets 4,985 3,861 1,078 46 Derivative liabilities (20) — (20) — Net assets $ 4,965 $ 3,861 $ 1,058 $ 46 December 31, 2019 (in millions) Total Fair Value Level 1 Level 2 Not Categorized NDTF cash and cash equivalents $ 21 $ 21 $ — $ — NDTF equity securities 3,154 3,103 — 51 NDTF debt securities 1,172 206 966 — Total assets 4,347 3,330 966 51 Derivative liabilities (49) — (49) — Net assets $ 4,298 $ 3,330 $ 917 $ 51 PROGRESS ENERGY The following table provides recorded balances for assets and liabilities measured at fair value on a recurring basis on the Consolidated Balance Sheets. December 31, 2020 December 31, 2019 (in millions) Total Fair Value Level 1 Level 2 Total Fair Value Level 1 Level 2 NDTF cash and cash equivalents $ 147 $ 147 $ — $ 80 $ 80 $ — NDTF equity securities 2,550 2,550 — 2,530 2,530 — NDTF debt securities 1,467 682 785 1,196 519 677 Other debt securities 26 — 26 51 — 51 Other cash and cash equivalents 106 106 49 49 — Derivative assets 33 — 33 7 — 7 Total assets 4,329 3,485 844 3,913 3,178 735 NDTF equity security contracts — — — (23) — (23) Derivative liabilities (29) — (29) (65) — (65) Net assets $ 4,300 $ 3,485 $ 815 $ 3,825 $ 3,178 $ 647 DUKE ENERGY PROGRESS The following table provides recorded balances for assets and liabilities measured at fair value on a recurring basis on the Consolidated Balance Sheets. December 31, 2020 December 31, 2019 (in millions) Total Fair Value Level 1 Level 2 Total Fair Value Level 1 Level 2 NDTF cash and cash equivalents $ 76 $ 76 $ — $ 53 $ 53 $ — NDTF equity securities 2,459 2,459 — 2,077 2,077 — NDTF debt securities 993 237 756 921 244 677 Other cash and cash equivalents 1 1 — 2 2 — Derivative assets 33 — 33 — — — Total assets 3,562 2,773 789 3,053 2,376 677 Derivative liabilities (14) — (14) (49) — (49) Net assets $ 3,548 $ 2,773 $ 775 $ 3,004 $ 2,376 $ 628 DUKE ENERGY FLORIDA The following table provides recorded balances for assets and liabilities measured at fair value on a recurring basis on the Consolidated Balance Sheets. December 31, 2020 December 31, 2019 (in millions) Total Fair Value Level 1 Level 2 Total Fair Value Level 1 Level 2 NDTF cash and cash equivalents $ 71 $ 71 $ — $ 27 $ 27 $ — NDTF equity securities 91 91 — 453 453 — NDTF debt securities 474 445 29 275 275 — Other debt securities 26 — 26 51 — 51 Other cash and cash equivalents 1 1 — 4 4 — Derivative assets — — — 7 — 7 Total assets 663 608 55 817 759 58 NDTF equity security contracts — — — (23) — (23) Derivative liabilities — — — (1) — (1) Net assets $ 663 $ 608 $ 55 $ 793 $ 759 $ 34 DUKE ENERGY OHIO The recorded balances for assets and liabilities measured at fair value on a recurring basis on the Consolidated Balance Sheets were not material at December 31, 2020, and 2019. DUKE ENERGY INDIANA The following table provides recorded balances for assets and liabilities measured at fair value on a recurring basis on the Consolidated Balance Sheets. December 31, 2020 December 31, 2019 (in millions) Total Fair Value Level 1 Level 2 Level 3 Total Fair Value Level 1 Level 2 Level 3 Other equity securities $ 97 $ 97 $ — $ — $ 81 $ 81 $ — $ — Other debt securities 45 — 45 — 44 — 44 — Other cash equivalents 1 1 — — — — — — Derivative assets 6 — — 6 13 2 — 11 Total assets 149 98 45 6 138 83 44 11 Derivative liabilities (1) (1) — — (1) (1) — — Total assets $ 148 $ 97 $ 45 $ 6 $ 137 $ 82 $ 44 $ 11 The following table provides a reconciliation of beginning and ending balances of assets and liabilities measured at fair value using Level 3 measurements. Derivatives (net) Years Ended December 31, (in millions) 2020 2019 Balance at beginning of period $ 11 $ 22 Purchases, sales, issuances and settlements: Purchases 10 28 Settlements (13) (36) Total losses included on the Consolidated Balance Sheet (2) (3) Balance at end of period $ 6 $ 11 PIEDMONT The following table provides recorded balances for assets and liabilities measured at fair value on a recurring basis on the Consolidated Balance Sheets. December 31, 2020 December 31, 2019 (in millions) Total Fair Value Level 1 Level 2 Total Fair Value Level 1 Level 3 Derivative assets $ 1 $ 1 $ — $ 1 $ 1 $ — Derivative liabilities (122) — (122) (117) — (117) Net (liabilities) assets $ (121) $ 1 $ (122) $ (116) $ 1 $ (117) The following table provides a reconciliation of beginning and ending balances of assets and liabilities measured at fair value using Level 3 measurements. Derivatives (net) Years Ended December 31, (in millions) 2020 2019 Balance at beginning of period $ (117) $ (141) Net transfers Out of Level 3 (a) 117 — Total gains and settlements — 24 Balance at end of period $ — $ (117) (a) Transferred from Level 3 to Level 2 because observable market data became available. QUANTITATIVE INFORMATION ABOUT UNOBSERVABLE INPUTS The following tables include quantitative information about the Duke Energy Registrants' derivatives classified as Level 3. December 31, 2020 Weighted Fair Value Average Investment Type (in millions) Valuation Technique Unobservable Input Range Range Duke Energy Electricity contracts $ (84) Discounted cash flow Forward electricity curves – price per MWh $ 14.68 – $ 151.84 $ 28.84 Duke Energy Ohio FTRs 1 RTO auction pricing FTR price – per MWh 0.25 – 1.68 0.79 Duke Energy Indiana FTRs 6 RTO auction pricing FTR price – per MWh (2.40) – 7.41 1.05 Duke Energy Total Level 3 derivatives $ (77) December 31, 2019 Weighted Fair Value Average Investment Type (in millions) Valuation Technique Unobservable Input Range Range Duke Energy Ohio FTRs $ 4 RTO auction pricing FTR price – per MWh $ 0.59 – $ 3.47 $ 2.07 Duke Energy Indiana FTRs 11 RTO auction pricing FTR price – per MWh (0.66) – 9.24 1.15 Piedmont Natural gas contracts (117) Discounted cash flow Forward natural gas curves – price per MMBtu 1.59 – 2.46 1.91 Duke Energy Total Level 3 derivatives $ (102) OTHER FAIR VALUE DISCLOSURES The fair value and book value of long-term debt, including current maturities, is summarized in the following table. Estimates determined are not necessarily indicative of amounts that could have been settled in current markets. Fair value of long-term debt uses Level 2 measurements. December 31, 2020 December 31, 2019 (in millions) Book Value Fair Value Book Value Fair Value Duke Energy (a) $ 59,863 $ 69,292 $ 58,126 $ 63,062 Duke Energy Carolinas 12,218 14,917 11,900 13,516 Progress Energy 19,264 23,470 19,634 22,291 Duke Energy Progress 9,258 10,862 9,058 9,934 Duke Energy Florida 7,915 9,756 7,987 9,131 Duke Energy Ohio 3,089 3,650 2,619 2,964 Duke Energy Indiana 4,091 5,204 4,057 4,800 Piedmont 2,780 3,306 2,384 2,642 (a) Book value of long-term debt includes $1.3 billion as of December 31, 2020, and $1.5 billion as of December 31, 2019, of unamortized debt discount and premium, net in purchase accounting adjustments related to the mergers with Progress Energy and Piedmont that are excluded from fair value of long-term debt. At both December 31, 2020, and December 31, 2019, fair value of cash and cash equivalents, accounts and notes receivable, accounts payable, notes payable and commercial paper, and nonrecourse notes payable of VIEs are not materially different from their carrying amounts because of the short-term nature of these instruments and/or because the stated rates approximate market rates.

Variable Interest Entities

Variable Interest Entities	12 Months Ended
	Dec. 31, 2020
Variable Interest Entities [Abstract]
Variable Interest Entities	VARIABLE INTEREST ENTITIES A VIE is an entity that is evaluated for consolidation using more than a simple analysis of voting control. The analysis to determine whether an entity is a VIE considers contracts with an entity, credit support for an entity, the adequacy of the equity investment of an entity and the relationship of voting power to the amount of equity invested in an entity. This analysis is performed either upon the creation of a legal entity or upon the occurrence of an event requiring reevaluation, such as a significant change in an entity’s assets or activities. A qualitative analysis of control determines the party that consolidates a VIE. This assessment is based on (i) what party has the power to direct the activities of the VIE that most significantly impact its economic performance and (ii) what party has rights to receive benefits or is obligated to absorb losses that could potentially be significant to the VIE. The analysis of the party that consolidates a VIE is a continual reassessment. CONSOLIDATED VIEs The obligations of the consolidated VIEs discussed in the following paragraphs are nonrecourse to the Duke Energy Registrants. The registrants have no requirement to provide liquidity to, purchase assets of or guarantee performance of these VIEs unless noted in the following paragraphs. No financial support was provided to any of the consolidated VIEs during the years ended December 31, 2020, 2019 and 2018, or is expected to be provided in the future, that was not previously contractually required. Receivables Financing – DERF/DEPR/DEFR DERF, DEPR and DEFR are bankruptcy remote, special purpose subsidiaries of Duke Energy Carolinas, Duke Energy Progress and Duke Energy Florida, respectively. DERF, DEPR and DEFR are wholly owned LLCs with separate legal existence from their parent companies, and their assets are not generally available to creditors of their parent companies. On a revolving basis, DERF, DEPR and DEFR buy certain accounts receivable arising from the sale of electricity and related services from their parent companies. DERF, DEPR and DEFR borrow amounts under credit facilities to buy these receivables. Borrowing availability from the credit facilities is limited to the amount of qualified receivables purchased, which generally exclude receivables past due more than a predetermined number of days and reserves for expected past-due balances. The sole source of funds to satisfy the related debt obligations is cash collections from the receivables. Amounts borrowed under the credit facilities for DERF and DEPR are reflected on the Consolidated Balance Sheets as Long-Term Debt. Amounts borrowed under the credit facilities for DEFR are reflected on the Consolidated Balance Sheets as Current maturities of long-term debt. Due to the COVID-19 pandemic, as described in Note 1, the Duke Energy Registrants suspended customer disconnections for nonpayment. Since taking action to suspend customer disconnections for nonpayment, certain jurisdictions have now returned to normal operations and billing practices. The full impact of COVID-19 and the Duke Energy Registrant’s related response on customers’ ability to pay for service is uncertain. However, the level of past-due receivables at Duke Energy Carolinas, Duke Energy Progress and Duke Energy Florida have increased significantly during the COVID-19 pandemic, and it is reasonably possible eventual write-offs of customer receivables may increase over current estimates. In 2020, DERF, DEPR and DEFR executed amendments to their credit facilities to manage the impact of past-due receivables resulting from the suspension of customer disconnections from COVID-19. See Note 3 for information about COVID-19 filings with state utility commissions. The most significant activity that impacts the economic performance of DERF, DEPR and DEFR are the decisions made to manage delinquent receivables. Duke Energy Carolinas, Duke Energy Progress and Duke Energy Florida are considered the primary beneficiaries and consolidate DERF, DEPR and DEFR, respectively, as they make those decisions. Receivables Financing – CRC CRC is a bankruptcy remote, special purpose entity indirectly owned by Duke Energy. On a revolving basis, CRC buys certain accounts receivable arising from the sale of electricity, natural gas and related services from Duke Energy Ohio and Duke Energy Indiana. CRC borrows amounts under a credit facility to buy the receivables from Duke Energy Ohio and Duke Energy Indiana. Borrowing availability from the credit facility is limited to the amount of qualified receivables sold to CRC, which generally exclude receivables past due more than a predetermined number of days and reserves for expected past-due balances. The sole source of funds to satisfy the related debt obligation is cash collections from the receivables. Amounts borrowed under the credit facility are reflected on Duke Energy's Consolidated Balance Sheets as Long-Term Debt. The proceeds Duke Energy Ohio and Duke Energy Indiana receive from the sale of receivables to CRC are approximately 75% cash and 25% in the form of a subordinated note from CRC. The subordinated note is a retained interest in the receivables sold. Depending on collection experience, additional equity infusions to CRC may be required by Duke Energy to maintain a minimum equity balance of $3 million. Due to the COVID-19 pandemic, as described in Note 1, the Duke Energy Registrants suspended customer disconnections for nonpayment. Since taking action to suspend customer disconnections for nonpayment, certain jurisdictions have now returned to normal operations and billing practices. The full impact of COVID-19 and the Duke Energy Registrant’s related response on customers’ ability to pay for service is uncertain. However, the level of past-due receivables at Duke Energy Ohio and Duke Energy Indiana have increased significantly during the COVID-19 pandemic, and it is reasonably possible eventual write-offs of customer receivables may increase over current estimates. In July of 2020, CRC executed an amendment to its credit facility to manage the impact of past-due receivables resulting from the suspension of customer disconnections from COVID-19. See Note 3 for information about COVID-19 filings with state utility commissions. CRC is considered a VIE because (i) equity capitalization is insufficient to support its operations, (ii) power to direct the activities that most significantly impact the economic performance of the entity is not held by the equity holder and (iii) deficiencies in net worth of CRC are funded by Duke Energy. The most significant activities that impact the economic performance of CRC are decisions made to manage delinquent receivables. Duke Energy is considered the primary beneficiary and consolidates CRC as it makes these decisions. Neither Duke Energy Ohio nor Duke Energy Indiana consolidate CRC. Receivables Financing – Credit Facilities The following table summarizes the amounts and expiration dates of the credit facilities and associated restricted receivables described above. Duke Energy Duke Energy Duke Energy Duke Energy Carolinas Progress Florida (in millions) CRC DERF DEPR DEFR Expiration date February 2023 December 2022 April 2023 April 2021 Credit facility amount $ 350 $ 475 $ 350 $ 250 Amounts borrowed at December 31, 2020 350 364 250 250 Amounts borrowed at December 31, 2019 350 474 325 250 Restricted Receivables at December 31, 2020 547 696 500 397 Restricted Receivables at December 31, 2019 522 642 489 336 Nuclear Asset-Recovery Bonds – Duke Energy Florida Project Finance, LLC (DEFPF) DEFPF is a bankruptcy remote, wholly owned special purpose subsidiary of Duke Energy Florida. DEFPF was formed in 2016 for the sole purpose of issuing nuclear asset-recovery bonds to finance Duke Energy Florida's unrecovered regulatory asset related to Crystal River Unit 3. In 2016, DEFPF issued senior secured bonds and used the proceeds to acquire nuclear asset-recovery property from Duke Energy Florida. The nuclear asset-recovery property acquired includes the right to impose, bill, collect and adjust a non-bypassable nuclear asset-recovery charge from all Duke Energy Florida retail customers until the bonds are paid in full and all financing costs have been recovered. The nuclear asset-recovery bonds are secured by the nuclear asset-recovery property and cash collections from the nuclear asset-recovery charges are the sole source of funds to satisfy the debt obligation. The bondholders have no recourse to Duke Energy Florida. DEFPF is considered a VIE primarily because the equity capitalization is insufficient to support its operations. Duke Energy Florida has the power to direct the significant activities of the VIE as described above and therefore Duke Energy Florida is considered the primary beneficiary and consolidates DEFPF. The following table summarizes the impact of DEFPF on Duke Energy Florida's Consolidated Balance Sheets. December 31, (in millions) 2020 2019 Receivables of VIEs $ 4 $ 5 Regulatory Assets: Current 53 52 Current Assets: Other 39 39 Other Noncurrent Assets: Regulatory assets 937 989 Current Liabilities: Other 10 10 Current maturities of long-term debt 55 54 Long-Term Debt 1,002 1,057 Commercial Renewables Certain of Duke Energy’s renewable energy facilities are VIEs due to Duke Energy issuing guarantees for debt service and operations and maintenance reserves in support of debt financings. Assets are restricted and cannot be pledged as collateral or sold to third parties without prior approval of debt holders. Additionally, Duke Energy has VIEs associated with tax equity arrangements entered into with third-party investors in order to finance the cost of renewable assets eligible for tax credits. The activities that most significantly impacted the economic performance of these renewable energy facilities were decisions associated with siting, negotiating PPAs and EPC agreements, and decisions associated with ongoing operations and maintenance-related activities. Duke Energy is considered the primary beneficiary and consolidates the entities as it is responsible for all of these decisions. The table below presents material balances reported on Duke Energy's Consolidated Balance Sheets related to Commercial Renewables VIEs. December 31, (in millions) 2020 2019 Current Assets: Other $ 257 $ 203 Property, Plant and Equipment: Cost 6,394 5,747 Accumulated depreciation and amortization (1,242) (1,041) Other Noncurrent Assets: Other 67 106 Current maturities of long-term debt 167 162 Long-Term Debt 1,569 1,541 Other Noncurrent Liabilities: AROs 148 127 Other Noncurrent Liabilities: Other 316 228 NON-CONSOLIDATED VIEs The following tables summarize the impact of non-consolidated VIEs on the Consolidated Balance Sheets. December 31, 2020 Duke Energy Duke Duke Pipeline Commercial Energy Energy (in millions) Investments Renewables Total Ohio Indiana Receivables from affiliated companies $ — $ — $ — $ 83 $ 110 Investments in equity method unconsolidated affiliates — 530 530 — — Other noncurrent assets 31 — 31 — — Total assets $ 31 $ 530 $ 561 $ 83 $ 110 Other current liabilities 928 5 933 — — Other noncurrent liabilities 8 10 18 — — Total liabilities $ 936 $ 15 $ 951 $ — $ — Net assets (liabilities) $ (905) $ 515 $ (390) $ 83 $ 110 December 31, 2019 Duke Energy Duke Duke Pipeline Commercial Energy Energy (in millions) Investments Renewables Total Ohio Indiana Receivables from affiliated companies $ — $ (1) $ (1) $ 64 $ 77 Investments in equity method unconsolidated affiliates 1,179 300 1,479 — — Total assets $ 1,179 $ 299 $ 1,478 $ 64 $ 77 Taxes accrued (1) — (1) — — Other current liabilities — 4 4 — — Deferred income taxes 59 — 59 — — Other noncurrent liabilities — 11 11 — — Total liabilities $ 58 $ 15 $ 73 $ — $ — Net assets $ 1,121 $ 284 $ 1,405 $ 64 $ 77 The Duke Energy Registrants are not aware of any situations where the maximum exposure to loss significantly exceeds the carrying values shown above except for the PPA with OVEC, which is discussed below, and future exit costs associated with the cancellation of the ACP pipeline, as discussed below. Pipeline Investments Duke Energy has investments in various joint ventures to construct and operate pipeline projects. These entities are considered VIEs due to having insufficient equity to finance their own activities without subordinated financial support. Duke Energy does not have the power to direct the activities that most significantly impact the economic performance, the obligation to absorb losses or the right to receive benefits of these VIEs and therefore does not consolidate these entities. Duke Energy has a 47% ownership interest in ACP. In 2020, Duke Energy determined that it would no longer invest in the construction of the ACP pipeline. The current liability related to the cancellation of the ACP pipeline represents Duke Energy's continuing obligation to fund its share of ACP's obligations. See Notes 3, 7 and 12 for further information regarding this transaction. Commercial Renewables Duke Energy has investments in various renewable energy project entities. Some of these entities are VIEs due to Duke Energy issuing guarantees for debt service and operations and maintenance reserves in support of debt financings. Duke Energy does not consolidate these VIEs because power to direct and control key activities is shared jointly by Duke Energy and other owners. OVEC Duke Energy Ohio’s 9% ownership interest in OVEC is considered a non-consolidated VIE due to OVEC having insufficient equity to finance its activities without subordinated financial support. The activities that most significantly impact OVEC's economic performance include fuel strategy and supply activities and decisions associated with ongoing operations and maintenance-related activities. Duke Energy Ohio does not have the unilateral power to direct these activities, and therefore, does not consolidate OVEC. As a counterparty to an Inter-Company Power Agreement (ICPA), Duke Energy Ohio has a contractual arrangement to receive entitlements to capacity and energy from OVEC’s power plants through June 2040 commensurate with its power participation ratio, which is equivalent to Duke Energy Ohio's ownership interest. Costs, including fuel, operating expenses, fixed costs, debt amortization and interest expense, are allocated to counterparties to the ICPA based on their power participation ratio. The value of the ICPA is subject to variability due to fluctuation in power prices and changes in OVEC's cost of business. On March 31, 2018, FES, a subsidiary of FirstEnergy Corp. and an ICPA counterparty with a power participation ratio of 4.85%, filed for Chapter 11 bankruptcy, which could increase costs allocated to the counterparties. On July 31, 2018, the bankruptcy court rejected the FES ICPA, which means OVEC is an unsecured creditor in the FES bankruptcy proceeding. Duke Energy Ohio cannot predict the impact of the bankruptcy filing on its OVEC interests. In addition, certain proposed environmental rulemaking could result in future increased OVEC cost allocations. In July 2020, legislation was proposed to repeal HB 6. Duke Energy cannot predict the outcome of this matter. See Note 3 for additional information. CRC See discussion under Consolidated VIEs for additional information related to CRC. Amounts included in Receivables from affiliated companies in the above table for Duke Energy Ohio and Duke Energy Indiana reflect their retained interest in receivables sold to CRC. These subordinated notes held by Duke Energy Ohio and Duke Energy Indiana are stated at fair value. Carrying values of retained interests are determined by allocating carrying value of the receivables between assets sold and interests retained based on relative fair value. The allocated bases of the subordinated notes are not materially different than their face value because (i) the receivables generally turnover in less than two months, (ii) credit losses are reasonably predictable due to the broad customer base and lack of significant concentration and (iii) the equity in CRC is subordinate to all retained interests and thus would absorb losses first. The hypothetical effect on fair value of the retained interests assuming both a 10% and a 20% unfavorable variation in credit losses or discount rates is not material due to the short turnover of receivables and historically low credit loss history. Interest accrues to Duke Energy Ohio and Duke Energy Indiana on the retained interests using the acceptable yield method. This method generally approximates the stated rate on the notes since the allocated basis and the face value are nearly equivalent. An impairment charge is recorded against the carrying value of both retained interests and purchased beneficial interest whenever it is determined that an OTTI has occurred. Key assumptions used in estimating fair value are detailed in the following table. Duke Energy Ohio Duke Energy Indiana 2020 2019 2020 2019 Anticipated credit loss ratio 0.5 % 0.6 % 0.3 % 0.3 % Discount rate 1.6 % 3.3 % 1.6 % 3.3 % Receivable turnover rate 13.4 % 13.4 % 11.3 % 11.5 % The following table shows the gross and net receivables sold. Duke Energy Ohio Duke Energy Indiana December 31, December 31, (in millions) 2020 2019 2020 2019 Receivables sold $ 270 $ 253 $ 344 $ 307 Less: Retained interests 83 64 110 77 Net receivables sold $ 187 $ 189 $ 234 $ 230 The following table shows sales and cash flows related to receivables sold. Duke Energy Ohio Duke Energy Indiana Years Ended December 31, Years Ended December 31, (in millions) 2020 2019 2018 2020 2019 2018 Sales Receivables sold $ 1,905 $ 1,979 $ 1,987 $ 2,631 $ 2,837 $ 2,842 Loss recognized on sale 10 14 13 12 17 16 Cash flows Cash proceeds from receivables sold 1,875 1,993 1,967 2,586 2,860 2,815 Collection fees received 1 1 1 1 1 1 Return received on retained interests 4 6 6 5 9 9 Cash flows from sales of receivables are reflected within Cash Flows From Operating Activities and Cash Flows from Investing Activities on Duke Energy Ohio’s and Duke Energy Indiana’s Consolidated Statements of Cash Flows. Collection fees received in connection with servicing transferred accounts receivable are included in Operation, maintenance and other on Duke Energy Ohio’s and Duke Energy Indiana’s Consolidated Statements of Operations and Comprehensive Income. The loss recognized on sales of receivables is calculated monthly by multiplying receivables sold during the month by the required discount. The required discount is derived monthly utilizing a three-year weighted average formula that considers charge-off history, late charge history and turnover history on the sold receivables, as well as a component for the time value of money. The discount rate, or component for the time value of money, is the prior month-end LIBOR plus a fixed rate of 1%.

Revenue

Revenue	12 Months Ended
	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Revenue	REVENUE Duke Energy recognizes revenue consistent with amounts billed under tariff offerings or at contractually agreed upon rates based on actual physical delivery of electric or natural gas service, including estimated volumes delivered when billings have not yet occurred. As such, the majority of Duke Energy’s revenues have fixed pricing based on the contractual terms of the published tariffs, with variability in expected cash flows attributable to the customer’s volumetric demand and ultimate quantities of energy or natural gas supplied and used during the billing period. The stand-alone selling price of related sales are designed to support recovery of prudently incurred costs and an appropriate return on invested assets and are primarily governed by published tariff rates or contractual agreements approved by relevant regulatory bodies. As described in Note 1, certain excise taxes and franchise fees levied by state or local governments are required to be paid even if not collected from the customer. These taxes are recognized on a gross basis as part of revenues. Duke Energy elects to account for all other taxes net of revenues. Performance obligations are satisfied over time as energy or natural gas is delivered and consumed with billings generally occurring monthly and related payments due within 30 days, depending on regulatory requirements. In no event does the timing between payment and delivery of the goods and services exceed one year. Using this output method for revenue recognition provides a faithful depiction of the transfer of electric and natural gas service as customers obtain control of the commodity and benefit from its use at delivery. Additionally, Duke Energy has an enforceable right to consideration for energy or natural gas delivered at any discrete point in time and will recognize revenue at an amount that reflects the consideration to which Duke Energy is entitled for the energy or natural gas delivered. As described above, the majority of Duke Energy’s tariff revenues are at-will and, as such, related contracts with customers have an expected duration of one year or less and will not have future performance obligations for disclosure. Additionally, other long-term revenue streams, including wholesale contracts, generally provide services that are part of a single performance obligation, the delivery of electricity or natural gas. As such, other than material fixed consideration under long-term contracts, related disclosures for future performance obligations are also not applicable. Duke Energy earns substantially all of its revenues through its reportable segments, Electric Utilities and Infrastructure, Gas Utilities and Infrastructure and Commercial Renewables. Electric Utilities and Infrastructure Electric Utilities and Infrastructure earns the majority of its revenues through retail and wholesale electric service through the generation, transmission, distribution and sale of electricity. Duke Energy generally provides retail and wholesale electric service customers with their full electric load requirements or with supplemental load requirements when the customer has other sources of electricity. Retail electric service is generally marketed throughout Duke Energy's electric service territory through standard service offers. The standard service offers are through tariffs determined by regulators in Duke Energy's regulated service territory. Each tariff, which is assigned to customers based on customer class, has multiple components such as an energy charge, a demand charge, a basic facilities charge and applicable riders. Duke Energy considers each of these components to be aggregated into a single performance obligation for providing electric service, or in the case of distribution only customers in Duke Energy Ohio, for delivering electricity. Electricity is considered a single performance obligation satisfied over time consistent with the series guidance and is provided and consumed over the billing period, generally one month. Retail electric service is typically provided to at-will customers who can cancel service at any time, without a substantive penalty. Additionally, Duke Energy adheres to applicable regulatory requirements in each jurisdiction to ensure the collectability of amounts billed and appropriate mitigating procedures are followed when necessary. As such, revenue from contracts with customers for such contracts is equivalent to the electricity supplied and billed in that period (including unbilled estimates). Wholesale electric service is generally provided under long-term contracts using cost-based pricing. FERC regulates costs that may be recovered from customers and the amount of return companies are permitted to earn. Wholesale contracts include both energy and demand charges. For full requirements contracts, Duke Energy considers both charges as a single performance obligation for providing integrated electric service. For contracts where energy and demand charges are considered separate performance obligations, energy and demand are each a distinct performance obligation under the series guidance and are satisfied as energy is delivered and stand-ready service is provided on a monthly basis. This service represents consumption over the billing period and revenue is recognized consistent with billings and unbilled estimates, which generally occur monthly. Contractual amounts owed are typically trued up annually based upon incurred costs in accordance with FERC published filings and the specific customer’s actual peak demand. Estimates of variable consideration related to potential additional billings or refunds owed are updated quarterly. The majority of wholesale revenues are full requirements contracts where the customers purchase the substantial majority of their energy needs and do not have a fixed quantity of contractually required energy or capacity. As such, related forecasted revenues are considered optional purchases. Supplemental requirements contracts that include contracted blocks of energy and capacity at contractually fixed prices have the following estimated remaining performance obligations: Remaining Performance Obligations (in millions) 2021 2022 2023 2024 2025 Thereafter Total Progress Energy $ 93 $ 107 $ 44 $ 45 $ 7 $ 51 $ 347 Duke Energy Progress 8 8 8 8 — — 32 Duke Energy Florida 85 99 36 37 7 51 315 Duke Energy Indiana 5 — 7 12 12 24 60 Revenues for block sales are recognized monthly as energy is delivered and stand-ready service is provided, consistent with invoiced amounts and unbilled estimates. Gas Utilities and Infrastructure Gas Utilities and Infrastructure earns its revenue through retail and wholesale natural gas service through the transportation, distribution and sale of natural gas. Duke Energy generally provides retail and wholesale natural gas service customers with all natural gas load requirements. Additionally, while natural gas can be stored, substantially all natural gas provided by Duke Energy is consumed by customers simultaneously with receipt of delivery. Retail natural gas service is marketed throughout Duke Energy's natural gas service territory using published tariff rates. The tariff rates are established by regulators in Duke Energy's service territories. Each tariff, which is assigned to customers based on customer class, have multiple components, such as a commodity charge, demand charge, customer or monthly charge and transportation costs. Duke Energy considers each of these components to be aggregated into a single performance obligation for providing natural gas service. For contracts where Duke Energy provides all of the customer’s natural gas needs, the delivery of natural gas is considered a single performance obligation satisfied over time, and revenue is recognized monthly based on billings and unbilled estimates as service is provided and the commodity is consumed over the billing period. Additionally, natural gas service is typically at-will and customers can cancel service at any time, without a substantive penalty. Duke Energy also adheres to applicable regulatory requirements to ensure the collectability of amounts billed and receivable and appropriate mitigating procedures are followed when necessary. Certain long-term individually negotiated contracts exist to provide natural gas service. These contracts are regulated and approved by state commissions. The negotiated contracts have multiple components, including a natural gas and a demand charge, similar to retail natural gas contracts. Duke Energy considers each of these components to be a single performance obligation for providing natural gas service. This service represents consumption over the billing period, generally one month. Fixed capacity payments under long-term contracts for the Gas Utilities and Infrastructure segment include minimum margin contracts and supply arrangements with municipalities and power generation facilities. Revenues for related sales are recognized monthly as natural gas is delivered and stand-ready service is provided, consistent with invoiced amounts and unbilled estimates. Estimated remaining performance obligations are as follows: Remaining Performance Obligations (in millions) 2021 2022 2023 2024 2025 Thereafter Total Piedmont $ 65 $ 64 $ 61 $ 59 $ 58 $ 319 $ 626 Commercial Renewables Commercial Renewables earns the majority of its revenues through long-term PPAs and generally sells all of its wind and solar facility output, electricity and RECs to customers. The majority of these PPAs have historically been accounted for as leases. For PPAs that are not accounted for as leases, the delivery of electricity and the delivery of RECs are considered separate performance obligations. The delivery of electricity is a performance obligation satisfied over time and represents generation and consumption of the electricity over the billing period, generally one month. The delivery of RECs is a performance obligation satisfied at a point in time and represents delivery of each REC generated by the wind or solar facility. The majority of self-generated RECs are bundled with energy in Duke Energy’s contracts and, as such, related revenues are recognized as energy is generated and delivered as that pattern is consistent with Duke Energy’s performance. Commercial Renewables recognizes revenue based on the energy generated and billed for the period, generally one month, at contractual rates (including unbilled estimates) according to the invoice practical expedient. Amounts are typically due within 30 days of invoice. Commercial Renewables also earns revenues from installation of distributed solar generation resources, which is primarily composed of EPC projects to deliver functioning solar power systems, generally completed within two to 12 months from commencement of construction. The installation of distributed solar generation resources is a performance obligation that is satisfied over time. Revenue from fixed-price EPC contracts is recognized using the input method as work is performed based on the estimated ratio of incurred costs to estimated total costs. Other The remainder of Duke Energy’s operations is presented as Other, which does not include material revenues from contracts with customers. Disaggregated Revenues For the Electric and Gas Utility and Infrastructure segments, revenue by customer class is most meaningful to Duke Energy as each respective customer class collectively represents unique customer expectations of service, generally has different energy and demand requirements, and operates under tailored, regulatory approved pricing structures. Additionally, each customer class is impacted differently by weather and a variety of economic factors including the level of population growth, economic investment, employment levels, and regulatory activities in each of Duke Energy’s jurisdictions. As such, analyzing revenues disaggregated by customer class allows Duke Energy to understand the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. For the Commercial Renewables segment, the majority of revenues from contracts with customers are from selling all of the unit-contingent output at contractually defined pricing under long-term PPAs with consistent expectations regarding the timing and certainty of cash flows. Disaggregated revenues are presented as follows: Year Ended December 31, 2020 Duke Duke Duke Duke Duke (in millions) Duke Energy Progress Energy Energy Energy Energy By market or type of customer Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Electric Utilities and Infrastructure Residential $ 9,806 $ 2,997 $ 5,017 $ 2,059 $ 2,958 $ 726 $ 1,064 $ — General 6,194 2,233 2,779 1,312 1,467 442 740 — Industrial 2,859 1,137 901 649 252 137 683 — Wholesale 1,864 380 1,228 1,034 194 32 224 — Other revenues 914 281 596 294 302 82 72 — Total Electric Utilities and Infrastructure revenue from contracts with customers $ 21,637 $ 7,028 $ 10,521 $ 5,348 $ 5,173 $ 1,419 $ 2,783 $ — Gas Utilities and Infrastructure Residential $ 930 $ — $ — $ — $ — $ 300 $ — $ 630 Commercial 446 — — — — 117 — 329 Industrial 127 — — — — 17 — 110 Power Generation — — — — — — — 34 Other revenues 87 — — — — 17 — 70 Total Gas Utilities and Infrastructure revenue from contracts with customers $ 1,590 $ — $ — $ — $ — $ 451 $ — $ 1,173 Commercial Renewables Revenue from contracts with customers $ 227 $ — $ — $ — $ — $ — $ — $ — Other Revenue from contracts with customers $ 26 $ — $ — $ — $ — $ — $ — $ — Total revenue from contracts with customers $ 23,480 $ 7,028 $ 10,521 $ 5,348 $ 5,173 $ 1,870 $ 2,783 $ 1,173 Other revenue sources (a) $ 388 $ (13) $ 106 $ 74 $ 15 $ (12) $ 12 $ 124 Total revenues $ 23,868 $ 7,015 $ 10,627 $ 5,422 $ 5,188 $ 1,858 $ 2,795 $ 1,297 (a) Other revenue sources include revenues from leases, derivatives and alternative revenue programs that are not considered revenues from contracts with customers. Alternative revenue programs in certain jurisdictions include regulatory mechanisms that periodically adjust for over or under collection of related revenues. Year Ended December 31, 2019 Duke Duke Duke Duke Duke (in millions) Duke Energy Progress Energy Energy Energy Energy By market or type of customer Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Electric Utilities and Infrastructure Residential $ 9,863 $ 3,044 $ 4,998 $ 2,144 $ 2,854 $ 733 $ 1,087 $ — General 6,431 2,244 2,935 1,368 1,567 451 802 — Industrial 3,071 1,215 934 675 259 147 774 — Wholesale 2,212 462 1,468 1,281 187 46 235 — Other revenues 770 276 548 317 231 80 89 — Total Electric Utilities and Infrastructure revenue from contracts with customers $ 22,347 $ 7,241 $ 10,883 $ 5,785 $ 5,098 $ 1,457 $ 2,987 $ — Gas Utilities and Infrastructure Residential $ 976 $ — $ — $ — $ — $ 315 $ — $ 661 Commercial 508 — — — — 130 — 378 Industrial 141 — — — — 19 — 122 Power Generation — — — — — — — 51 Other revenues 129 — — — — 19 — 110 Total Gas Utilities and Infrastructure revenue from contracts with customers $ 1,754 $ — $ — $ — $ — $ 483 $ — $ 1,322 Commercial Renewables Revenue from contracts with customers $ 223 $ — $ — $ — $ — $ — $ — $ — Other Revenue from contracts with customers $ 24 $ — $ — $ — $ — $ — $ — $ — Total revenue from contracts with customers $ 24,348 $ 7,241 $ 10,883 $ 5,785 $ 5,098 $ 1,940 $ 2,987 $ 1,322 Other revenue sources (a) $ 731 $ 154 $ 319 $ 172 $ 133 $ — $ 17 $ 59 Total revenues $ 25,079 $ 7,395 $ 11,202 $ 5,957 $ 5,231 $ 1,940 $ 3,004 $ 1,381 (a) Other revenue sources include revenues from leases, derivatives and alternative revenue programs that are not considered revenues from contracts with customers. Alternative revenue programs in certain jurisdictions include regulatory mechanisms that periodically adjust for over or under collection of related revenues. Year Ended December 31, 2018 Duke Duke Duke Duke Duke (in millions) Duke Energy Progress Energy Energy Energy Energy By market or type of customer Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Electric Utilities and Infrastructure Residential $ 9,587 $ 2,981 $ 4,785 $ 2,019 $ 2,766 $ 743 $ 1,076 $ — General 6,127 2,119 2,809 1,280 1,529 422 778 — Industrial 2,974 1,180 904 642 262 131 760 — Wholesale 2,324 508 1,462 1,303 159 57 298 — Other revenues 717 320 502 320 182 73 91 — Total Electric Utilities and Infrastructure revenue from contracts with customers $ 21,729 $ 7,108 $ 10,462 $ 5,564 $ 4,898 $ 1,426 $ 3,003 $ — Gas Utilities and Infrastructure Residential $ 1,000 $ — $ — $ — $ — $ 331 $ — $ 669 Commercial 514 — — — — 135 — 378 Industrial 147 — — — — 18 — 128 Power Generation — — — — — — — 54 Other revenues 139 — — — — 19 — 120 Total Gas Utilities and Infrastructure revenue from contracts with customers $ 1,800 $ — $ — $ — $ — $ 503 $ — $ 1,349 Commercial Renewables Revenue from contracts with customers $ 209 $ — $ — $ — $ — $ — $ — $ — Other Revenue from contracts with customers $ 19 $ — $ — $ — $ — $ 1 $ — $ — Total revenue from contracts with customers $ 23,757 $ 7,108 $ 10,462 $ 5,564 $ 4,898 $ 1,930 $ 3,003 $ 1,349 Other revenue sources (a) $ 764 $ 192 $ 266 $ 135 $ 123 $ 27 $ 56 $ 26 Total revenues $ 24,521 $ 7,300 $ 10,728 $ 5,699 $ 5,021 $ 1,957 $ 3,059 $ 1,375 (a) Other revenue sources include revenues from leases, derivatives and alternative revenue programs that are not considered revenues from contracts with customers. Alternative revenue programs in certain jurisdictions include regulatory mechanisms that periodically adjust for over or under collection of related revenues. As described in Note 1, Duke Energy adopted the new guidance for credit losses effective January 1, 2020, using the modified retrospective method of adoption, which does not require restatement of prior year reported results. The following table presents the reserve for credit losses for trade and other receivables based on adoption of the new standard. Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Balance at December 31, 2019 $ 76 $ 10 $ 16 $ 8 $ 7 $ 4 $ 3 $ 6 Cumulative Change in Accounting Principle 5 1 2 1 1 — — 1 Write-Offs (58) (13) (23) (8) (14) — — (6) Credit Loss Expense 75 13 29 9 20 — — 11 Other Adjustments 48 12 13 13 — — — — Balance at December 31, 2020 $ 146 $ 23 $ 37 $ 23 $ 14 $ 4 $ 3 $ 12 Trade and other receivables are evaluated based on an estimate of the risk of loss over the life of the receivable and current and historical conditions using supportable assumptions. Management evaluates the risk of loss for trade and other receivables by comparing the historical write-off amounts to total revenue over a specified period. Historical loss rates are adjusted due to the impact of current conditions, including the impacts of COVID-19, as well as forecasted conditions over a reasonable time period. The calculated write-off rate can be applied to the receivable balance for which an established reserve does not already exist. Management reviews the assumptions and risk of loss periodically for trade and other receivables. Due to the COVID-19 pandemic, as described in Note 1, certain jurisdictions have resumed standard billing and credit practices, disconnections for nonpayment and late payment charges, all of which were previously suspended in the first quarter of 2020. The specific actions taken by each Duke Energy Registrant are described in Note 3 and the impact of COVID-19 on certain receivables financing entities are described in Note 17. The impact of COVID-19 and Duke Energy’s related response on customers’ ability to pay for service is uncertain, and it is reasonably possible eventual write-offs of customer receivables may increase over current estimates. The aging of trade receivables is presented in the table below. Duke Energy considers receivables greater than 30 days outstanding past due. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Unbilled Receivables $ 969 $ 328 $ 283 $ 167 $ 116 $ 2 $ 16 $ 86 0-30 days 1,789 445 707 398 307 60 26 149 30-60 days 185 80 54 25 29 8 3 8 60-90 days 22 1 10 4 6 2 1 3 90+ days 119 16 32 9 23 30 12 9 Deferred Payment Arrangements (a) 215 96 80 52 28 — — 7 Trade and Other Receivables $ 3,299 $ 966 $ 1,166 $ 655 $ 509 $ 102 $ 58 $ 262 (a) Due to certain customer financial hardships created by the COVID-19 pandemic and resulting stay-at-home orders, Duke Energy permitted customers to defer payment of past-due amounts through an installment payment plan over a period of several months. IMPACT OF WEATHER AND THE TIMING OF BILLING PERIODS Revenues and costs are influenced by seasonal weather patterns. Peak sales of electricity occur during the summer and winter months, which results in higher revenue and cash flows during these periods. By contrast, lower sales of electricity occur during the spring and fall, allowing for scheduled plant maintenance. Residential and general service customers are more impacted by weather than industrial customers. Estimated weather impacts are based on actual current period weather compared to normal weather conditions. Normal weather conditions are defined as the long-term average of actual historical weather conditions. Heating degree days measure the variation in weather based on the extent the average daily temperature falls below a base temperature. Cooling degree days measure the variation in weather based on the extent the average daily temperature rises above the base temperature. Each degree of temperature below the base temperature counts as one heating degree day and each degree of temperature above the base temperature counts as one cooling degree day. The estimated impact of weather on earnings for Electric Utilities and Infrastructure is based on the temperature variances from a normal condition and customers' historic usage patterns. The methodology used to estimate the impact of weather does not consider all variables that may impact customer response to weather conditions, such as humidity in the summer or wind chill in the winter. The precision of this estimate may also be impacted by applying long-term weather trends to shorter-term periods. Gas Utilities and Infrastructure's costs and revenues are influenced by seasonal patterns due to peak natural gas sales occurring during the winter months as a result of space heating requirements. Residential customers are the most impacted by weather. There are certain regulatory mechanisms for the North Carolina, South Carolina, Tennessee, Ohio and Kentucky service territories that normalize the margins collected from certain customer classes during the winter. In North Carolina, rate design provides protection from both weather and other usage variations such as conservation, while South Carolina, Tennessee and Kentucky revenues are adjusted solely based on weather. Ohio primarily employs a fixed charge each month regardless of the season and usage. UNBILLED REVENUE Unbilled revenues are recognized by applying customer billing rates to the estimated volumes of energy or natural gas delivered but not yet billed. Unbilled revenues can vary significantly from period to period as a result of seasonality, weather, customer usage patterns, customer mix, average price in effect for customer classes, timing of rendering customer bills and meter reading schedules, and the impact of weather normalization or margin decoupling mechanisms. Unbilled revenues are included within Receivables and Receivables of VIEs on the Consolidated Balance Sheets as shown in the following table. December 31, (in millions) 2020 2019 Duke Energy $ 969 $ 843 Duke Energy Carolinas 328 298 Progress Energy 283 217 Duke Energy Progress 167 122 Duke Energy Florida 116 95 Duke Energy Ohio 2 1 Duke Energy Indiana 16 16 Piedmont 86 78 Additionally, Duke Energy Ohio and Duke Energy Indiana sell, on a revolving basis, nearly all of their retail accounts receivable, including receivables for unbilled revenues, to an affiliate, CRC and account for the transfers of receivables as sales. Accordingly, the receivables sold are not reflected on the Consolidated Balance Sheets of Duke Energy Ohio and Duke Energy Indiana. See Note 17 for further information. These receivables for unbilled revenues are shown in the table below. December 31, (in millions) 2020 2019 Duke Energy Ohio $ 87 $ 82 Duke Energy Indiana 134 115

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Stockholders' Equity	STOCKHOLDERS' EQUITY Basic EPS is computed by dividing net income available to Duke Energy common stockholders, as adjusted for distributed and undistributed earnings allocated to participating securities and accumulated preferred dividends, by the weighted average number of common shares outstanding during the period. Diluted EPS is computed by dividing net income available to Duke Energy common stockholders, as adjusted for distributed and undistributed earnings allocated to participating securities and accumulated preferred dividends, by the diluted weighted average number of common shares outstanding during the period. Diluted EPS reflects the potential dilution that could occur if securities or other agreements to issue common stock, such as equity forward sale agreements, were exercised or settled. Duke Energy’s participating securities are RSUs that are entitled to dividends declared on Duke Energy common stock during the RSUs vesting periods. Dividends declared on preferred stock are recorded on the Consolidated Statements of Operations as a reduction of net income to arrive at net income available to Duke Energy common stockholders. Dividends accumulated on preferred stock are an adjustment to net income used in the calculation of basic and diluted EPS. The following table presents Duke Energy’s basic and diluted EPS calculations, the weighted average number of common shares outstanding and common and preferred share dividends declared. Years Ended December 31, (in millions, except per share amounts) 2020 2019 2018 Net Income available to Duke Energy common stockholders $ 1,270 $ 3,707 $ 2,666 Less: Income (Loss) from discontinued operations 7 (7) 19 Accumulated preferred stock dividends adjustment 1 (15) — Less: Impact of participating securities 2 5 5 Income from continuing operations available to Duke Energy common stockholders $ 1,262 $ 3,694 $ 2,642 Weighted average common shares outstanding – basic 737 729 708 Equity forwards 1 — — Weighted average common shares outstanding – diluted 738 729 708 EPS from continuing operations available to Duke Energy common stockholders Basic and Diluted $ 1.71 $ 5.07 $ 3.73 Potentially dilutive items excluded from the calculation (a) 2 2 2 Dividends declared per common share $ 3.82 $ 3.75 $ 3.64 Dividends declared on Series A preferred stock per depositary share $ 1.437 $ 1.03 $ — Dividends declared on Series B preferred stock per share $ 49.292 $ — $ — (a) Performance stock awards were not included in the dilutive securities calculation because the performance measures related to the awards had not been met. Common Stock In November 2019, Duke Energy filed a prospectus supplement and executed an Equity Distribution Agreement (EDA) under which it may sell up to $1.5 billion of its common stock through a new ATM offering program, including an equity forward sales component. Under the terms of the EDA, Duke Energy may issue and sell shares of common stock through September 2022. Separately, in November 2019, Duke Energy marketed an equity offering of 28.75 million shares of common stock through an Underwriting Agreement. In connection with the offering, Duke Energy entered into equity forward sales agreements with an initial forward price of $85.99 per share. In March 2020, Duke Energy marketed approximately 940,000 shares of common stock through an equity forward transaction under the ATM with an initial forward price of $89.76 per share. In May 2020, Duke Energy marketed approximately 903,000 shares of common stock through an equity forward transaction under the ATM with an initial forward price of $82.44 per share. In August 2020, Duke Energy marketed approximately 936,000 shares of common stock through an equity forward transaction under the ATM with an initial forward price of $79.52 per share. In December 2020, Duke Energy physically settled the equity forwards by delivering 32 million shares of common stock in exchange for net cash proceeds of approximately $2.6 billion. Preferred Stock On March 29, 2019, Duke Energy completed the issuance of 40 million depositary shares, each representing 1/1,000th share of its Series A Cumulative Redeemable Perpetual Preferred Stock, at a price of $25 per depositary share. The transaction resulted in net proceeds of $973 million after issuance costs with proceeds used for general corporate purposes and to reduce short-term debt. The preferred stock has a $25 liquidation preference per depositary share and earns dividends on a cumulative basis at a rate of 5.75% per annum. Dividends are payable quarterly in arrears on the 16th day of March, June, September and December, and began on June 16, 2019. The Series A Preferred Stock has no maturity or mandatory redemption date, is not redeemable at the option of the holders and includes separate call options. The first call option allows Duke Energy to call the Series A Preferred Stock at a redemption price of $25.50 per depositary share prior to June 15, 2024, in whole but not in part, at any time within 120 days after a ratings event where a rating agency amends, clarifies or changes the criteria it uses to assign equity credit for securities such as the preferred stock. The second call option allows Duke Energy to call the preferred stock, in whole or in part, at any time, on or after June 15, 2024, at a redemption price of $25 per depositary share. Duke Energy is also required to redeem all accumulated and unpaid dividends if either call option is exercised. On September 12, 2019, Duke Energy completed the issuance of 1 million shares of its Series B Fixed-Rate Reset Cumulative Redeemable Perpetual Preferred Stock, at a price of $1,000 per share. The transaction resulted in net proceeds of $989 million after issuance costs with proceeds being used to pay down short-term debt, repay at maturity $500 million senior notes due September 2019, and for general corporate purposes. The preferred stock has a $1,000 liquidation preference per share and earns dividends on a cumulative basis at an initial rate of 4.875% per annum. Dividends are payable semiannually in arrears on the 16th day of March and September, and began on March 16, 2020. On September 16, 2024, the First Call Date, and any fifth anniversary of the First Call Date (each a Reset Date), the dividend rate will reset based on the then current five-year U.S. Treasury rate plus a spread of 3.388%. The Series B Preferred Stock has no maturity or mandatory redemption date, is not redeemable at the option of the holders and includes separate call options. The first call option allows Duke Energy to call the Series B Preferred Stock at a redemption price of $1,020 per share, in whole but not in part, at any time within 120 days after a ratings event. The second call option allows Duke Energy to call the preferred stock, in whole or in part, on the First Call Date or any subsequent Reset Date at a redemption price in cash equal to $1,000 per share. Duke Energy is also required to redeem all accumulated and unpaid dividends if either call option is exercised. Dividends issued on its Series A and Series B Preferred Stock are subject to approval by the Board of Directors. However, the deferral of dividend payments on the preferred stock prohibits the declaration of common stock dividends. The Series A and Series B Preferred Stock rank, with respect to dividends and distributions upon liquidation or dissolution: • senior to Common Stock and to each other class or series of capital stock established after the original issue date of the Series A and Series B Preferred Stock that is expressly made subordinated to the Series A and Series B Preferred Stock; • on a parity with any class or series of capital stock established after the original issue date of the Series A and Series B Preferred Stock that is not expressly made senior or subordinated to the Series A or Series B Preferred Stock; • junior to any class or series of capital stock established after the original issue date of the Series A and Series B Preferred Stock that is expressly made senior to the Series A or Series B Preferred Stock; • junior to all existing and future indebtedness (including indebtedness outstanding under Duke Energy's credit facilities, unsecured senior notes, junior subordinated debentures and commercial paper) and other liabilities with respect to assets available to satisfy claims against Duke Energy; and • structurally subordinated to existing and future indebtedness and other liabilities of Duke Energy's subsidiaries and future preferred stock of subsidiaries.

Severance

Severance	12 Months Ended
	Dec. 31, 2020
Restructuring and Related Activities [Abstract]
Severance	SEVERANCE During 2020, as a result of partial settlements between Duke Energy Carolinas, Duke Energy Progress and the Public Staff, Duke Energy Carolinas and Duke Energy Progress deferred as Regulatory assets on the Consolidated Balance Sheets, approximately $65 million and $33 million, respectively, of previously recorded severance charges within Operation, maintenance and other on the Consolidated Statements of Operations. These severance charges were previously recorded during 2018, as Duke Energy reviewed its operations and identified opportunities for improvement to better serve its customers. This operational review included the company's workforce strategy and staffing levels to ensure the company was staffed with the right skill sets and number of teammates to execute the long-term vision for Duke Energy. As such, Duke Energy extended voluntary and involuntary severance benefits to certain employees in specific areas as a part of workforce planning and digital transformation efforts. See Note 3 for more information. The following table presents the direct and allocated severance and related charges accrued for approximately 30 e mployees in 2020, 140 employees in 2019, and 1,900 employees in 2018, by the Duke Energy Registrants within Operation, maintenance and other on the Consolidated Statements of Operations. Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Year Ended December 31, 2020 (a)(b) $ (85) $ (58) $ (28) $ (31) $ 3 $ — $ — $ — Year Ended December 31, 2019 16 8 6 3 3 — 1 1 Year Ended December 31, 2018 187 102 69 52 17 6 7 2 (a) Includes unamortized deferred severance charges of approximately $(86) million, $(57) million, $(29) million and $(29) million for Duke Energy, Duke Energy Carolinas, Progress Energy and Duke Energy Progress, respectively. (b) Includes adjustments associated with 2018 severance charges of approximately $(6) million, $(2) million, $(3) million and $(2) million for Duke Energy, Duke Energy Carolinas, Progress Energy and Duke Energy Progress, respectively. The table below presents the severance liability for past and ongoing severance plans including the plans described above. Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Balance at December 31, 2019 $ 41 $ 11 $ 13 $ 6 $ 7 $ 1 $ 2 $ — Provision/Adjustments 1 — — (2) 2 (1) — — Cash Reductions (31) (9) (10) (3) (7) — (1) — Balance at December 31, 2020 $ 11 $ 2 $ 3 $ 1 $ 2 $ — $ 1 $ —

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation	STOCK-BASED COMPENSATIONThe Duke Energy Corporation 2015 Long-Term Incentive Plan (the 2015 Plan) provides for the grant of stock-based compensation awards to employees and outside directors. The 2015 Plan reserves 10 million shares of common stock for issuance. Duke Energy has historically issued new shares upon exercising or vesting of share-based awards. However, Duke Energy may use a combination of new share issuances and open market repurchases for share-based awards that are exercised or vest in the future. Duke Energy has not determined with certainty the amount of such new share issuances or open market repurchases. The following table summarizes the total expense recognized by the Duke Energy Registrants, net of tax, for stock-based compensation. Years Ended December 31, (in millions) 2020 2019 2018 Duke Energy $ 61 $ 65 $ 56 Duke Energy Carolinas 22 24 20 Progress Energy 23 24 21 Duke Energy Progress 15 15 13 Duke Energy Florida 9 9 8 Duke Energy Ohio 4 5 4 Duke Energy Indiana 6 6 5 Piedmont 3 3 3 Duke Energy's pretax stock-based compensation costs, the tax benefit associated with stock-based compensation expense and stock-based compensation costs capitalized are included in the following table. Years Ended December 31, (in millions) 2020 2019 2018 RSU awards $ 46 $ 44 $ 43 Performance awards 38 45 35 Pretax stock-based compensation cost $ 84 $ 89 $ 78 Stock-based compensation costs capitalized 5 5 5 Stock-based compensation expense $ 79 $ 84 $ 73 Tax benefit associated with stock-based compensation expense $ 18 $ 19 $ 17 RESTRICTED STOCK UNIT AWARDS RSU awards generally vest over periods from immediate to three years. Fair value amounts are based on the market price of Duke Energy's common stock on the grant date. The following table includes information related to RSU awards. Years Ended December 31, 2020 2019 2018 Shares granted (in thousands) 498 571 649 Fair value (in millions) $ 50 $ 51 $ 49 The following table summarizes information about RSU awards outstanding. Weighted Average Shares Grant Date Fair Value (in thousands) (per share) Outstanding at December 31, 2019 1,010 $ 83 Granted 498 100 Vested (532) 82 Forfeited (37) 92 Outstanding at December 31, 2020 939 93 RSU awards expected to vest 898 93 The total grant date fair value of shares vested during the years ended December 31, 2020, 2019 and 2018, was $43 million, $49 million and $43 million, respectively. At December 31, 2020, Duke Energy had $31 million of unrecognized compensation cost, which is expected to be recognized over a weighted average period of 23 months. PERFORMANCE AWARDS Stock-based performance awards generally vest after three years if performance targets are met. The actual number of shares issued will range from zero to 200% of target shares, depending on the level of performance achieved. Performance awards contain performance conditions and a market condition. The performance conditions are based on Duke Energy's cumulative adjusted EPS and total incident case rate (total incident case rate is one of our key employee safety metrics). The market condition is based on TSR of Duke Energy relative to a predefined peer group. Relative TSR is valued using a path-dependent model that incorporates expected relative TSR into the fair value determination of Duke Energy’s performance-based share awards. The model uses three-year historical volatilities and correlations for all companies in the predefined peer group, including Duke Energy, to simulate Duke Energy’s relative TSR as of the end of the performance period. For each simulation, Duke Energy’s relative TSR associated with the simulated stock price at the end of the performance period plus expected dividends within the period results in a value per share for the award portfolio. The average of these simulations is the expected portfolio value per share. Actual life to date results of Duke Energy’s relative TSR for each grant are incorporated within the model. For performance awards granted in 2020, the model used a risk-free interest rate of 1.4%, which reflects the yield on three-year Treasury bonds as of the grant date, and an expected volatility of 13.6% based on Duke Energy's historical volatility over three years using daily stock prices. The following table includes information related to stock-based performance awards. Years Ended December 31, 2020 2019 2018 Shares granted assuming target performance (in thousands) 319 320 372 Fair value (in millions) $ 34 $ 27 $ 27 The following table summarizes information about stock-based performance awards outstanding and assumes payout at the target level. Weighted Average Shares Grant Date Fair Value (in thousands) (per share) Outstanding at December 31, 2019 1,109 $ 80 Granted 319 105 Vested (448) 81 Forfeited (18) 88 Outstanding at December 31, 2020 962 87 Stock-based performance awards expected to vest 937 87 The total grant date fair value of shares vested during the years ended December 31, 2020, and 2019, was $36 million and $23 million, respectively. At December 31, 2020, Duke Energy had $23 million of unrecognized compensation cost, which is expected to be recognized over a weighted average period of 21 months.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2020
Retirement Benefits [Abstract]
Employee Benefit Plans	EMPLOYEE BENEFIT PLANS DEFINED BENEFIT RETIREMENT PLANS Duke Energy and certain subsidiaries maintain, and the Subsidiary Registrants participate in, qualified, non-contributory defined benefit retirement plans. The Duke Energy plans cover most employees using a cash balance formula. Under a cash balance formula, a plan participant accumulates a retirement benefit consisting of pay credits based upon a percentage of current eligible earnings, age or age and years of service and interest credits. Certain employees are eligible for benefits that use a final average earnings formula. Under these final average earnings formulas, a plan participant accumulates a retirement benefit equal to the sum of percentages of their (i) highest three-year, four-year, or five-year average earnings, (ii) highest three-year, four-year, or five-year average earnings in excess of covered compensation per year of participation (maximum of 35 years) or (iii) highest three-year average earnings times years of participation in excess of 35 years. Duke Energy also maintains, and the Subsidiary Registrants participate in, non-qualified, non-contributory defined benefit retirement plans that cover certain executives. The qualified and non-qualified, non-contributory defined benefit plans are closed to new participants. Duke Energy uses a December 31 measurement date for its defined benefit retirement plan assets and obligations. Actuarial gains experienced by the defined benefit retirement plans in remeasuring plan assets as of December 31, 2020, and 2019, were attributable to actual investment performance that exceeded expected investment performance. Actuarial losses experienced by the defined benefit retirement plans in remeasuring plan obligations as of December 31, 2020, and 2019, were primarily attributable to the decrease in the discount rate used to measure plan obligations. As a result of the application of settlement accounting due to total lump-sum benefit payments exceeding the settlement threshold (defined as the sum of the service cost and interest cost on projected benefit obligation components of net periodic pension costs) for one of its qualified pension plans, Duke Energy recognized settlement charges of $94 million, primarily as a regulatory asset within Other Noncurrent Assets on the Consolidated Balance Sheets as of December 31, 2019 (an immaterial amount was recorded in Other income and expenses, net within the Consolidated Statement of Operations). Settlement charges recognized by the Subsidiary Registrants as of December 31, 2019, which represent amounts allocated by Duke Energy for employees of the Subsidiary Registrants and allocated charges for their proportionate share of settlement charges for employees of Duke Energy’s shared services affiliate, were $53 million for Duke Energy Carolinas, $26 million for Progress Energy, $20 million for Duke Energy Progress, $6 million for Duke Energy Florida, $4 million for Duke Energy Indiana, $2 million for Duke Energy Ohio and $8 million for Piedmont. The settlement charges reflect the recognition of a pro-rata portion of previously unrecognized actuarial losses, equal to the percentage of reduction in the projected benefit obligation resulting from total lump - sum benefit payments as of December 31, 2019. Settlement charges recognized as a regulatory asset within Other Noncurrent Assets on the Consolidated Balance Sheets are amortized over the average remaining service period for participants in the plan. Amortization of settlement charges is disclosed in the tables below as a component of net periodic pension costs. Net periodic benefit costs disclosed in the tables below represent the cost of the respective benefit plan for the periods presented prior to capitalization of amounts reflected as Net property, plant and equipment, on the Consolidated Balance Sheets. Only the service cost component of net periodic benefit costs is eligible to be capitalized. The remaining non-capitalized portions of net periodic benefit costs are classified as either: (1) service cost, which is recorded in Operations, maintenance and other on the Consolidated Statements of Operations; or as (2) components of non-service cost, which is recorded in Other income and expenses, net, on the Consolidated Statements of Operations. Amounts presented in the tables below for the Subsidiary Registrants represent the amounts of pension and other post-retirement benefit cost allocated by Duke Energy for employees of the Subsidiary Registrants. Additionally, the Consolidated Statements of Operations of the Subsidiary Registrants also include allocated net periodic benefit costs for their proportionate share of pension and post-retirement benefit cost for employees of Duke Energy’s shared services affiliate that provide support to the Subsidiary Registrants. However, in the tables below, these amounts are only presented within the Duke Energy column (except for amortization of settlement charges). These allocated amounts are included in the governance and shared service costs discussed in Note 13. Duke Energy’s policy is to fund amounts on an actuarial basis to provide assets sufficient to meet benefit payments to be paid to plan participants. Duke Energy does not anticipate making any contributions in 2021. The following table includes information related to the Duke Energy Registrants’ contributions to its qualified defined benefit pension plans. Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Contributions Made: 2020 $ — $ — $ — $ — $ — $ — $ — $ — 2019 77 7 57 4 53 2 2 1 2018 141 46 45 25 20 — 8 — QUALIFIED PENSION PLANS Components of Net Periodic Pension Costs Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Service cost $ 165 $ 51 $ 48 $ 27 $ 21 $ 5 $ 9 $ 6 Interest cost on projected benefit obligation 269 62 85 38 46 15 22 9 Expected return on plan assets (572) (145) (190) (87) (101) (28) (42) (21) Amortization of actuarial loss 128 28 41 18 23 6 12 9 Amortization of prior service credit (32) (8) (3) (2) (1) — (2) (9) Amortization of settlement charges 18 9 7 6 1 — 1 1 Net periodic pension costs (a)(b) $ (24) $ (3) $ (12) $ — $ (11) $ (2) $ — $ (5) Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Service cost $ 158 $ 49 $ 46 $ 26 $ 20 $ 4 $ 9 $ 5 Interest cost on projected benefit obligation 317 75 100 45 54 18 26 10 Expected return on plan assets (567) (147) (178) (88) (89) (28) (43) (22) Amortization of actuarial loss 108 24 39 15 24 4 8 8 Amortization of prior service credit (32) (8) (3) (2) (1) — (2) (9) Amortization of settlement charges 6 2 1 1 — 2 — — Net periodic pension costs (a)(b) $ (10) $ (5) $ 5 $ (3) $ 8 $ — $ (2) $ (8) Year Ended December 31, 2018 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Service cost $ 182 $ 58 $ 51 $ 29 $ 22 $ 5 $ 11 $ 7 Interest cost on projected benefit obligation 299 72 94 43 50 17 23 11 Expected return on plan assets (559) (147) (178) (85) (91) (28) (42) (22) Amortization of actuarial loss 132 29 44 21 23 5 10 11 Amortization of prior service credit (32) (8) (3) (2) (1) — (2) (10) Net periodic pension costs (a)(b) $ 22 $ 4 $ 8 $ 6 $ 3 $ (1) $ — $ (3) (a) Duke Energy amounts exclude $4 million, $4 million and $5 million for the years ended December 2020, 2019 and 2018, respectively, of regulatory asset amortization resulting from purchase accounting adjustments associated with Duke Energy's merger with Cinergy in April 2006. (b) Duke Energy Ohio amounts exclude $2 million, $2 million and $2 million for the years ended December 2020, 2019 and 2018, respectively, of regulatory asset amortization resulting from purchase accounting adjustments associated with Duke Energy's merger with Cinergy in April 2006. Amounts Recognized in Accumulated Other Comprehensive Income and Regulatory Assets Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Regulatory assets, net increase (decrease) $ (62) $ (39) $ (26) $ (30) $ 4 $ (2) $ 5 $ (1) Accumulated other comprehensive loss (income) Deferred income tax expense (benefit) $ 2 $ — $ 1 $ — $ 1 $ — $ — $ — Amortization of prior year service credit 1 — — — — — — — Amortization of prior year actuarial losses (11) — (1) — (3) — — — Net amount recognized in accumulated other comprehensive income $ (8) $ — $ — $ — $ (2) $ — $ — $ — Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Regulatory assets, net (decrease) increase $ (212) $ (156) $ (79) $ (59) $ (20) $ 12 $ 22 $ — Accumulated other comprehensive (income) loss Deferred income tax expense (benefit) $ 20 $ — $ 1 $ — $ (1) $ — $ — $ — Amortization of prior year service credit 1 — — — — — — — Amortization of prior year actuarial losses (15) — (2) — 3 — — — Net amount recognized in accumulated other comprehensive income $ 6 $ — $ (1) $ — $ 2 $ — $ — $ — Reconciliation of Funded Status to Net Amount Recognized Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Change in Projected Benefit Obligation Obligation at prior measurement date $ 8,321 $ 1,923 $ 2,608 $ 1,170 $ 1,424 $ 481 $ 693 $ 292 Service cost 157 49 46 26 20 4 8 5 Interest cost 269 62 85 38 46 15 22 9 Actuarial loss 433 83 144 50 93 21 46 14 Transfers — 8 (8) (8) — 15 — — Benefits paid (541) (137) (160) (83) (76) (34) (49) (27) Benefits paid – settlements (5) — — — — — (5) — Obligation at measurement date $ 8,634 $ 1,988 $ 2,715 $ 1,193 $ 1,507 $ 502 $ 715 $ 293 Accumulated Benefit Obligation at measurement date $ 8,577 $ 1,989 $ 2,684 $ 1,194 $ 1,476 $ 493 $ 709 $ 294 Change in Fair Value of Plan Assets Plan assets at prior measurement date $ 8,910 $ 2,263 $ 2,898 $ 1,364 $ 1,515 $ 443 $ 667 $ 335 Actual return on plan assets 973 247 319 149 166 48 71 35 Benefits paid (541) (137) (160) (83) (76) (34) (49) (27) Benefits paid – settlements (5) — — — — — (5) — Transfers — 8 (8) (8) — 15 — — Plan assets at measurement date $ 9,337 $ 2,381 $ 3,049 $ 1,422 $ 1,605 $ 472 $ 684 $ 343 Funded status of plan $ 703 $ 393 $ 334 $ 229 $ 98 $ (30) $ (31) $ 50 Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Change in Projected Benefit Obligation Obligation at prior measurement date $ 7,869 $ 1,954 $ 2,433 $ 1,125 $ 1,295 $ 435 $ 618 $ 264 Service cost 150 47 43 25 18 4 8 5 Interest cost 317 75 100 45 54 18 26 10 Actuarial loss 716 101 223 87 135 54 87 33 Transfers — 11 — — — — — — Benefits paid (731) (265) (191) (112) (78) (30) (46) (20) Obligation at measurement date $ 8,321 $ 1,923 $ 2,608 $ 1,170 $ 1,424 $ 481 $ 693 $ 292 Accumulated Benefit Obligation at measurement date $ 8,262 $ 1,923 $ 2,578 $ 1,170 $ 1,392 $ 471 $ 686 $ 292 Change in Fair Value of Plan Assets Plan assets at prior measurement date $ 8,233 $ 2,168 $ 2,606 $ 1,268 $ 1,322 $ 405 $ 611 $ 305 Employer contributions 77 7 57 4 53 2 2 1 Actual return on plan assets 1,331 342 426 204 218 66 100 49 Benefits paid (731) (265) (191) (112) (78) (30) (46) (20) Transfers — 11 — — — — — — Plan assets at measurement date $ 8,910 $ 2,263 $ 2,898 $ 1,364 $ 1,515 $ 443 $ 667 $ 335 Funded status of plan $ 589 $ 340 $ 290 $ 194 $ 91 $ (38) $ (26) $ 43 Amounts Recognized in the Consolidated Balance Sheets December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Prefunded pension (a) $ 780 $ 393 $ 379 $ 229 $ 143 $ 58 $ 79 $ 50 Noncurrent pension liability (b) $ 77 $ — $ 45 $ — $ 45 $ 88 $ 110 $ — Net asset (liability) recognized $ 703 $ 393 $ 334 $ 229 $ 98 $ (30) $ (31) $ 50 Regulatory assets $ 1,910 $ 381 $ 691 $ 283 $ 408 $ 110 $ 209 $ 80 Accumulated other comprehensive (income) loss Deferred income tax benefit $ (21) $ — $ — $ — $ — $ — $ — $ — Prior service credit (2) — — — — — — — Net actuarial loss 100 — 2 — — — — — Net amounts recognized in accumulated other comprehensive loss $ 77 $ — $ 2 $ — $ — $ — $ — $ — December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Prefunded pension (a) $ 621 $ 340 $ 322 $ 194 $ 123 $ 38 $ 57 $ 43 Noncurrent pension liability (b) $ 32 $ — $ 32 $ — $ 32 $ 76 $ 83 $ — Net asset recognized $ 589 $ 340 $ 290 $ 194 $ 91 $ (38) $ (26) $ 43 Regulatory assets $ 1,972 $ 420 $ 717 $ 313 $ 404 $ 112 $ 204 $ 81 Accumulated other comprehensive (income) loss Deferred income tax benefit $ (23) $ — $ (1) $ — $ (1) $ — $ — $ — Prior service credit (3) — — — — — — — Net actuarial loss 111 — 3 — 3 — — — Net amounts recognized in accumulated other comprehensive loss $ 85 $ — $ 2 $ — $ 2 $ — $ — $ — Amounts to be recognized in net periodic pension costs in the next year Unrecognized net actuarial loss $ 135 $ 29 $ 43 $ 19 $ 24 $ 7 $ 10 $ 9 Unrecognized prior service credit (32) (8) (3) (2) (1) (1) (2) (9) (a) Included in Other within Other Noncurrent Assets on the Consolidated Balance Sheets. (b) Included in Accrued pension and other post-retirement benefit costs on the Consolidated Balance Sheets. Information for Plans with Accumulated Benefit Obligation in Excess of Plan Assets December 31, 2020 Duke Duke Duke Duke Progress Energy Energy Energy (in millions) Energy Energy Florida Ohio Indiana Projected benefit obligation $ 4,914 $ 828 $ 828 $ 184 $ 293 Accumulated benefit obligation 4,856 796 796 176 285 Fair value of plan assets 4,837 783 783 96 183 December 31, 2019 Duke Duke Energy Energy (in millions) Ohio Indiana Projected benefit obligation $ 155 $ 260 Accumulated benefit obligation 146 252 Fair value of plan assets 79 177 Assumptions Used for Pension Benefits Accounting The discount rate used to determine the current year pension obligation and following year’s pension expense is based on a bond selection-settlement portfolio approach. This approach develops a discount rate by selecting a portfolio of high-quality corporate bonds that generate sufficient cash flow to provide for projected benefit payments of the plan. The selected bond portfolio is derived from a universe of non-callable corporate bonds rated Aa quality or higher. After the bond portfolio is selected, a single interest rate is determined that equates the present value of the plan’s projected benefit payments discounted at this rate with the market value of the bonds selected. The average remaining service period for participants in active plans and life expectancy of participants in inactive plans is 13 years for Duke Energy, Duke Energy Indiana and Duke Energy Ohio, 14 years for Progress Energy, Duke Energy Progress and Duke Energy Florida, 12 years for Duke Energy Carolinas and nine years for Piedmont. The following tables present the assumptions or range of assumptions used for pension benefit accounting. December 31, 2020 2019 2018 Benefit Obligations Discount rate 2.60% 3.30% 4.30% Interest crediting rate 4.00% 4.00% 4.00% Salary increase 3.50 % – 4.00% 3.50 % – 4.00% 3.50 % – 4.00% Net Periodic Benefit Cost Discount rate 3.30% 4.30% 3.60% Interest crediting rate 4.00% 4.00% 4.00% Salary increase 3.50 % – 4.00% 3.50 % – 4.00% 3.50 % – 4.00% Expected long-term rate of return on plan assets 6.85% 6.85% 6.50% Expected Benefit Payments Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Years ending December 31, 2021 $ 667 $ 169 $ 177 $ 94 $ 82 $ 40 $ 53 $ 29 2022 650 170 176 92 83 39 51 25 2023 655 174 181 95 85 38 49 22 2024 644 168 184 96 87 37 49 21 2025 617 163 181 93 88 35 47 19 2025-2029 2,745 677 846 399 443 154 217 83 NON-QUALIFIED PENSION PLANS The accumulated benefit obligation, which equals the projected benefit obligation for non-qualified pension plans, was $320 million for Duke Energy, $13 million for Duke Energy Carolinas, $111 million for Progress Energy, $33 million for Duke Energy Progress, $45 million for Duke Energy Florida, $4 million for Duke Energy Ohio, $2 million for Duke Energy Indiana and $4 million for Piedmont as of December 31, 2020. Employer contributions, which equal benefits paid for non-qualified pension plans, were $23 million for Duke Energy, $2 million for Duke Energy Carolinas, $8 million for Progress Energy, $3 million for Duke Energy Progress and $3 million for Duke Energy Florida for the year ended December 31, 2020. Employer contributions were not material for Duke Energy Ohio, Duke Energy Indiana or Piedmont for the year ended December 31, 2020. Net periodic pension costs for non-qualified pension plans were not material for the years ended December 31, 2020, 2019 or 2018. OTHER POST-RETIREMENT BENEFIT PLANS Duke Energy provides, and the Subsidiary Registrants participate in, some health care and life insurance benefits for retired employees on a contributory and non-contributory basis. Employees are eligible for these benefits if they have met age and service requirements at retirement, as defined in the plans. The health care benefits include medical, dental and prescription drug coverage and are subject to certain limitations, such as deductibles and copayments. Duke Energy did not make any pre-funding contributions to its other post-retirement benefit plans during the years ended December 31, 2020, 2019 or 2018. Components of Net Periodic Other Post-Retirement Benefit Costs Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Service cost $ 4 $ 1 $ 1 $ — $ — $ — $ 1 $ — Interest cost on accumulated post-retirement benefit obligation 23 5 10 5 4 1 2 1 Expected return on plan assets (13) (8) — — — — — (2) Amortization of actuarial loss 2 — 1 — 1 — 4 — Amortization of prior service credit (14) (4) (3) (1) (2) (1) (1) (2) Net periodic post-retirement benefit costs (a)(b) $ 2 $ (6) $ 9 $ 4 $ 3 $ — $ 6 $ (3) Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Service cost $ 4 $ 1 $ 1 $ — $ 1 $ — $ 1 $ — Interest cost on accumulated post-retirement benefit obligation 30 7 12 7 5 1 3 1 Expected return on plan assets (12) (7) — — — — — (1) Amortization of actuarial loss 4 2 1 — 1 — 4 — Amortization of prior service credit (19) (5) (8) (1) (7) (1) (1) (2) Net periodic post-retirement benefit costs (a)(b) $ 7 $ (2) $ 6 $ 6 $ — $ — $ 7 $ (2) Year Ended December 31, 2018 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Service cost $ 6 $ 1 $ 1 $ — $ 1 $ 1 $ 1 $ 1 Interest cost on accumulated post-retirement benefit obligation 28 7 12 6 6 1 3 1 Expected return on plan assets (13) (8) — — — — — (2) Amortization of actuarial loss 6 3 1 1 — — 4 — Amortization of prior service credit (19) (5) (8) (1) (7) (1) (1) (2) Net periodic post-retirement benefit costs (a)(b) $ 8 $ (2) $ 6 $ 6 $ — $ 1 $ 7 $ (2) (a) Duke Energy amounts exclude $6 million, $6 million and $7 million for the years ended December 2020, 2019 and 2018, respectively, of regulatory asset amortization resulting from purchase accounting adjustments associated with Duke Energy's merger with Cinergy in April 2006. (b) Duke Energy Ohio amounts exclude $1 million, $2 million and $2 million for the years ended December 2020, 2019 and 2018, respectively, of regulatory asset amortization resulting from purchase accounting adjustments associated with Duke Energy's merger with Cinergy in April 2006. Amounts Recognized in Accumulated Other Comprehensive Income and Regulatory Assets and Liabilities Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Regulatory assets, net increase (decrease) $ 9 $ — $ 9 $ 6 $ 3 $ — $ (4) $ — Regulatory liabilities, net increase (decrease) $ (10) $ (7) $ — $ — $ — $ — $ (1) $ — Accumulated other comprehensive (income) loss Deferred income tax benefit $ — $ — $ — $ — $ — $ — $ — $ — Amortization of prior year service credit 1 — — — — — — — Net amount recognized in accumulated other comprehensive income $ 1 $ — $ — $ — $ — $ — $ — $ — Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Regulatory assets, net increase (decrease) $ (127) $ — $ (127) $ (82) $ (45) $ — $ (5) $ — Regulatory liabilities, net increase (decrease) $ (152) $ 1 $ (149) $ (93) $ (56) $ (1) $ (4) $ 3 Accumulated other comprehensive (income) loss Deferred income tax benefit $ — $ — $ — $ — $ — $ — $ — $ — Amortization of prior year actuarial gain (4) — — — — — — — Net amount recognized in accumulated other comprehensive income $ (4) $ — $ — $ — $ — $ — $ — $ — Reconciliation of Funded Status to Accrued Other Post-Retirement Benefit Costs Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Change in Projected Benefit Obligation Accumulated post-retirement benefit obligation at prior measurement date $ 723 $ 175 $ 303 $ 168 $ 135 $ 29 $ 64 $ 30 Service cost 4 1 1 — — — 1 — Interest cost 23 5 10 5 4 1 2 1 Plan participants' contributions 15 3 5 3 2 1 2 — Actuarial losses 19 8 8 5 2 — 1 1 Benefits paid (75) (18) (28) (15) (13) (4) (9) (2) Accumulated post-retirement benefit obligation at measurement date $ 709 $ 174 $ 299 $ 166 $ 130 $ 27 $ 61 $ 30 Change in Fair Value of Plan Assets Plan assets at prior measurement date $ 220 $ 130 $ (1) $ (1) $ — $ 9 $ 5 $ 34 Actual return on plan assets 24 14 — — — — 1 4 Benefits paid (75) (18) (28) (15) (13) (4) (9) (2) Employer contributions 53 10 23 11 10 3 8 1 Plan participants' contributions 15 3 5 3 2 1 2 — Plan assets at measurement date $ 237 $ 139 $ (1) $ (2) $ (1) $ 9 $ 7 $ 37 Funded status of plan $ (472) $ (35) $ (300) $ (168) $ (131) $ (18) $ (54) $ 7 Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Change in Projected Benefit Obligation Accumulated post-retirement benefit obligation at prior measurement date $ 728 $ 174 $ 303 $ 166 $ 137 $ 29 $ 67 $ 30 Service cost 4 1 1 — 1 — 1 — Interest cost 30 7 12 7 5 1 3 1 Plan participants' contributions 16 3 6 3 2 1 2 — Actuarial losses 28 9 13 9 5 1 2 — Benefits paid (83) (19) (32) (17) (15) (3) (11) (1) Accumulated post-retirement benefit obligation at measurement date $ 723 $ 175 $ 303 $ 168 $ 135 $ 29 $ 64 $ 30 Change in Fair Value of Plan Assets Plan assets at prior measurement date $ 195 $ 115 $ — $ — $ — $ 8 $ 5 $ 29 Actual return on plan assets 32 20 (1) — — 1 — 6 Benefits paid (83) (19) (32) (17) (15) (3) (11) (1) Employer contributions 60 11 26 13 13 2 9 — Plan participants' contributions 16 3 6 3 2 1 2 — Plan assets at measurement date $ 220 $ 130 $ (1) $ (1) $ — $ 9 $ 5 $ 34 Funded status of plan $ (503) $ (45) $ (304) $ (169) $ (135) $ (20) $ (59) $ 4 Amounts Recognized in the Consolidated Balance Sheets December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Prefunded post-retirement benefit $ 8 $ — $ — $ — $ — $ 1 $ — $ 7 Current post-retirement liability (a) 9 — 6 4 2 2 — — Noncurrent post-retirement liability (b) 471 35 294 164 129 17 54 — Net liability (asset) recognized $ 472 $ 35 $ 300 $ 168 $ 131 $ 18 $ 54 $ (7) Regulatory assets $ 144 $ — $ 144 $ 88 $ 56 $ — $ 32 $ — Regulatory liabilities $ 139 $ 32 $ — $ — $ — $ 17 $ 62 $ 3 Accumulated other comprehensive (income) loss Deferred income tax expense $ 3 $ — $ — $ — $ — $ — $ — $ — Prior service credit (1) — — — — — — — Net actuarial gain (13) — — — — — — — Net amounts recognized in accumulated other comprehensive income $ (11) $ — $ — $ — $ — $ — $ — $ — December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Current post-retirement liability (a) $ 9 $ — $ 5 $ 3 $ 2 $ 1 $ — $ — Noncurrent post-retirement liability (b) 494 45 299 163 133 19 59 (4) Total accrued post-retirement liability $ 503 $ 45 $ 304 $ 166 $ 135 $ 20 $ 59 $ (4) Regulatory assets $ 135 $ — $ 135 $ 82 $ 53 $ — $ 36 $ — Regulatory liabilities $ 149 $ 39 $ — $ — $ — $ 17 $ 63 $ 3 Accumulated other comprehensive (income) loss Deferred income tax expense $ 3 $ — $ — $ — $ — $ — $ — $ — Prior service credit (2) — — — — — — — Net actuarial gain (13) — — — — — — — Net amounts recognized in accumulated other comprehensive income $ (12) $ — $ — $ — $ — $ — $ — $ — Amounts to be recognized in net periodic pension expense in the next year Unrecognized net actuarial loss $ 5 $ 3 $ 1 $ — $ 1 $ — $ — $ — Unrecognized prior service credit (14) (4) (3) (1) (2) (1) (1) (2) (a) Included in Other within Current Liabilities on the Consolidated Balance Sheets. (b) Included in Accrued pension and other post-retirement benefit costs on the Consolidated Balance Sheets. Assumptions Used for Other Post-Retirement Benefits Accounting The discount rate used to determine the current year other post-retirement benefits obligation and following year’s other post-retirement benefits expense is based on a bond selection-settlement portfolio approach. This approach develops a discount rate by selecting a portfolio of high-quality corporate bonds that generate sufficient cash flow to provide for projected benefit payments of the plan. The selected bond portfolio is derived from a universe of non-callable corporate bonds rated Aa quality or higher. After the bond portfolio is selected, a single interest rate is determined that equates the present value of the plan’s projected benefit payments discounted at this rate with the market value of the bonds selected. The average remaining service period of active covered employees is eight years for Duke Energy, seven years for Progress Energy, Duke Energy Florida and Duke Energy Ohio and six years for Duke Energy Carolinas, Duke Energy Progress, Duke Energy Indiana and Piedmont. The following tables present the assumptions used for other post-retirement benefits accounting. December 31, 2020 2019 2018 Benefit Obligations Discount rate 2.60 % 3.30 % 4.30 % Net Periodic Benefit Cost Discount rate 3.30 % 4.30 % 3.60 % Expected long-term rate of return on plan assets 6.85 % 6.85 % 6.50 % Assumed tax rate 23 % 23 % 35 % Assumed Health Care Cost Trend Rate December 31, 2020 2019 Health care cost trend rate assumed for next year 6.25 % 6.00 % Rate to which the cost trend is assumed to decline (the ultimate trend rate) 4.75 % 4.75 % Year that rate reaches ultimate trend 2028 2026 Expected Benefit Payments Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Years ending December 31, 2021 $ 73 $ 17 $ 28 $ 15 $ 12 $ 3 $ 8 $ 2 2022 66 16 26 14 12 3 7 2 2023 62 15 25 14 11 3 6 2 2024 58 14 24 13 11 2 6 2 2025 54 13 22 12 10 2 5 2 2026-2030 223 54 94 52 41 9 21 11 PLAN ASSETS Description and Allocations Duke Energy Master Retirement Trust Assets for both the qualified pension and other post-retirement benefits are maintained in the Duke Energy Master Retirement Trust. Approximately 98% of the Duke Energy Master Retirement Trust assets were allocated to qualified pension plans and approximately 2% were allocated to other post-retirement plans (comprised of 401(h) accounts), as of December 31, 2020, and 2019. The investment objective of the Duke Energy Master Retirement Trust is to invest in a diverse portfolio of assets that is expected to generate positive surplus return over time (i.e., asset growth greater than liability growth) subject to a prudent level of portfolio risk, for the purpose of enhancing the security of benefits for plan participants. As of December 31, 2020, Duke Energy assumes pension and other post-retirement plan assets will generate a long-term rate of return of 6.5%. The expected long-term rate of return was developed using a weighted average calculation of expected returns based primarily on future expected returns across asset classes considering the use of active asset managers, where applicable. The asset allocation targets were set after considering the investment objective and the risk profile. Equity securities are held for their higher expected returns. Debt securities are primarily held to hedge the qualified pension plan. Return seeking debt securities, hedge funds and other global securities are held for diversification. Investments within asset classes are diversified to achieve broad market participation and reduce the impact of individual managers or investments. Effective January 1, 2020, the target asset allocation for the Duke Energy Retirement Master Trust is 58% liability hedging assets and 42% return-seeking assets. Duke Energy periodically reviews its asset allocation targets, and over time, as the funded status of the benefit plans increase, the level of asset risk relative to plan liabilities may be reduced to better manage Duke Energy's benefit plan liabilities and reduce funded status volatility. The Duke Energy Master Retirement Trust is authorized to engage in the lending of certain plan assets. Securities lending is an investment management enhancement that utilizes certain existing securities of the Duke Energy Master Retirement Trust to earn additional income. Securities lending involves the loaning of securities to approved parties. In return for the loaned securities, the Duke Energy Master Retirement Trust receives collateral in the form of cash and securities as a safeguard against possible default of any borrower on the return of the loan under terms that permit the Duke Energy Master Retirement Trust to sell the securities. The Duke Energy Master Retirement Trust mitigates credit risk associated with securities lending arrangements by monitoring the fair value of the securities loaned, with additional collateral obtained or refunded as necessary. The fair value of securities on loan was approximately $482 million and $351 million at December 31, 2020, and 2019, respectively. Cash and securities obtained as collateral exceeded the fair value of the securities loaned at December 31, 2020, and 2019, respectively. Securities lending income earned by the Duke Energy Master Retirement Trust was immaterial for the years ended December 31, 2020, 2019 and 2018, respectively. Qualified pension and other post-retirement benefits for the Subsidiary Registrants are derived from the Duke Energy Master Retirement Trust, as such, each are allocated their proportionate share of the assets discussed below. The following table includes the target asset allocations by asset class at December 31, 2020, and the actual asset allocations for the Duke Energy Master Retirement Trust. Actual Allocation at Target December 31, Allocation 2020 2019 Global equity securities 28 % 30 % 27 % Global private equity securities 1 % 1 % 1 % Debt securities 58 % 55 % 57 % Return seeking debt securities 4 % 5 % 5 % Hedge funds 3 % 3 % 3 % Real estate and cash 6 % 6 % 7 % Total 100 % 100 % 100 % Other post-retirement assets Duke Energy's other post-retirement assets are comprised of Voluntary Employees' Beneficiary Association (VEBA) trusts and 401(h) accounts held within the Duke Energy Master Retirement Trust. Duke Energy's investment objective is to achieve sufficient returns, subject to a prudent level of portfolio risk, for the purpose of promoting the security of plan benefits for participants. The following table presen

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES Consolidated Appropriations Act On December 27, 2020, President Trump signed the Consolidated Appropriations Act (CAA) into law. In addition to the CAA providing funding for government operations, it also provided tax provisions to assist with COVID-19 relief, including extending certain expiring tax provisions. The Company has reviewed the provisions of the CAA and has determined that there is no material impact on the 2020 financial statements as a result of the CAA being signed into law. CARES Act On March 27, 2020, the CARES Act was enacted. The CARES Act is an emergency economic stimulus package in response to the COVID-19 pandemic. Among other provisions, the CARES Act accelerates the remaining AMT credit refund allowances resulting in taxpayers being able to immediately claim a refund in full for any AMT credit carryforwards and deferral of certain 2020 payroll taxes. In the third quarter of 2020, Duke Energy received $572 million related to these AMT credit carryforwards and $19 million of interest income. In addition, the Company has deferred approximately $117 million of payroll taxes, with 50% payable by December 31, 2021, and the remaining 50% payable by December 31, 2022. The other provisions within the CARES Act do not materially impact Duke Energy's income tax accounting. See Note 1 for information on COVID-19. Tax Act On December 22, 2017, President Trump signed the Tax Act into law. Among other provisions, the Tax Act lowered the corporate federal income tax rate from 35% to 21%, limits interest deductions outside of regulated utility operations, requires the normalization of excess deferred taxes associated with property under the average rate assumption method as a prerequisite to qualifying for accelerated depreciation and repealed the federal manufacturing deduction. The Tax Act also repealed the corporate AMT and stipulates a refund of 50% of remaining AMT credit carryforwards (to the extent the credits exceed regular tax for the year) for tax years 2018, 2019, and 2020, with all remaining AMT credits to be refunded in tax year 2021. On December 22, 2017, the SEC staff issued Staff Accounting Bulletin (SAB) 118, Income Tax Accounting Implications of the Tax Cuts and Jobs Act, which provides guidance on accounting for the Tax Act’s impact. SAB 118 provides a measurement period, which in no case should extend beyond one year from the Tax Act enactment date, during which a company acting in good faith may complete the accounting for the impacts of the Tax Act under ASC Topic 740. In accordance with SAB 118, a company must reflect the income tax effects of the Tax Act in the reporting period in which the accounting under ASC Topic 740 is complete. To the extent that a company’s accounting for certain income tax effects of the Tax Act is incomplete, a company can determine a reasonable estimate for those effects and record a provisional estimate in the financial statements in the first reporting period in which a reasonable estimate can be determined. As of December 31, 2018, the accounting for the effects of the Tax Act was complete. During the year ended December 31, 2018, Duke Energy recorded the following measurement period adjustments in accordance with SAB 118: • Additional tax expense of $23 million related to the completion of the analysis of Duke Energy’s existing regulatory liability related to deferred taxes; • A $10 million tax benefit for the remeasurement of deferred tax assets and deferred tax liabilities primarily related to the guidance on bonus depreciation issued by the IRS in August 2018, affecting the computation of the Company's 2017 Federal income tax liability; • Additional tax expense of $7 million related to the portion of the deferred tax asset as of December 31, 2017, that represents nondeductible long-term incentives under the Tax Act’s limitation on the deductibility of executive compensation; and • During the fourth quarter of 2018, the Company released the $76 million valuation allowance that it recorded in the first quarter of 2018 as a result of additional guidance published by the IRS that stated refundable AMT credits would not be subject to sequestration. • The majority of Duke Energy’s operations are regulated and it is expected that the Subsidiary Registrants will ultimately pass on the savings associated with the amount representing the remeasurement of deferred tax balances related to regulated operations to customers. For Duke Energy's regulated operations, where the reduction is expected to be returned to customers in future rates, the remeasurement has been deferred as a regulatory liability. During 2018, Duke Energy recorded an additional regulatory liability of $83 million, representing the revaluation of those deferred tax balances. The Subsidiary Registrants continue to respond to requests from regulators in various jurisdictions to determine the timing and magnitude of savings they will pass on to customers. In addition, during 2018, Duke Energy reclassified $573 million of AMT credit carryforwards from noncurrent deferred tax liabilities to a current federal income tax receivable. In 2019, Duke Energy received a refund of $573 million related to AMT credit carryforwards based on the filing of Duke Energy's 2018 income tax return in 2019 and reclassified $286 million of AMT credits from noncurrent deferred tax liabilities to a current federal income tax receivable. Income Tax Expense Components of Income Tax Expense Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Current income taxes Federal $ (281) $ 314 $ 280 $ 181 $ 148 $ 10 $ 48 $ (27) State (9) 35 29 17 24 1 7 (8) Foreign 1 — — — — — — — Total current income taxes (289) 349 309 198 172 11 55 (35) Deferred income taxes Federal 155 (171) (167) (180) 1 30 12 60 State (92) (86) (24) (49) 25 2 17 (7) Total deferred income taxes (a) 63 (257) (191) (229) 26 32 29 53 ITC amortization (10) (4) (5) (5) — — — — Income tax (benefit) expense from continuing operations (236) 88 113 (36) 198 43 84 18 Tax expense from discontinued operations 2 — — — — — — — Total income tax (benefit) expense included in Consolidated Statements of Operations $ (234) $ 88 $ 113 $ (36) $ 198 $ 43 $ 84 $ 18 (a) Total deferred income taxes includes the generation of NOL carryforwards and tax credit carryforwards of $20 million at Duke Energy Carolinas, $3 million at Duke Energy Progress, $8 million at Duke Energy Indiana, and $11 million at Piedmont. In addition, total deferred income taxes includes utilization of NOL carryforwards and tax credit carryforwards of $39 million at Progress Energy, $30 million at Duke Energy Florida and $79 million at Duke Energy. Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Current income taxes Federal $ (299) $ 164 $ (173) $ (36) $ (43) $ (41) $ (23) $ (92) State 10 13 (7) (3) 18 (1) 1 (1) Foreign 2 — — — — — — — Total current income taxes (287) 177 (180) (39) (25) (42) (22) (93) Deferred income taxes Federal 855 175 422 220 153 77 128 133 State (38) (37) 17 (18) 27 5 28 3 Total deferred income taxes (a) 817 138 439 202 180 82 156 136 ITC amortization (11) (4) (6) (6) — — — — Income tax expense from continuing operations 519 311 253 157 155 40 134 43 Tax benefit from discontinued operations (2) — — — — — — — Total income tax expense included in Consolidated Statements of Operations $ 517 $ 311 $ 253 $ 157 $ 155 $ 40 $ 134 $ 43 (a) Total deferred income taxes includes the generation of tax credit carryforwards of $8 million at Duke Energy Carolinas. In addition, total deferred income taxes includes utilization of NOL carryforwards and tax credit carryforwards of $243 million at Progress Energy, $35 million at Duke Energy Progress, $152 million at Duke Energy Florida, $25 million at Duke Energy Ohio, $60 million at Duke Energy Indiana, $90 million at Piedmont and $775 million at Duke Energy. Year Ended December 31, 2018 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Current income taxes Federal $ (647) $ (8) $ (135) $ (71) $ (49) $ 20 $ 29 $ 67 State (11) 6 (5) (5) (10) (1) 3 1 Foreign 3 — — — — — — — Total current income taxes (655) (2) (140) (76) (59) 19 32 68 Deferred income taxes Federal 1,064 299 341 256 115 21 74 (36) State 49 11 20 (17) 45 3 22 5 Total deferred income taxes (a)(b) 1,113 310 361 239 160 24 96 (31) ITC amortization (10) (5) (3) (3) — — — — Income tax expense from continuing operations 448 303 218 160 101 43 128 37 Tax benefit from discontinued operations (26) — — — — — — — Total income tax expense included in Consolidated Statements of Operations $ 422 $ 303 $ 218 $ 160 $ 101 $ 43 $ 128 $ 37 (a) Includes benefits of NOL carryforwards and tax credit carryforwards of $22 million at Duke Energy Carolinas, $293 million at Progress Energy, $59 million at Duke Energy Progress, $219 million at Duke Energy Florida, $17 million at Duke Energy Ohio, $21 million at Duke Energy Indiana and $39 million at Piedmont. In addition, total deferred income taxes includes utilization of NOL carryforwards and tax credit carryforwards of $18 million at Duke Energy. (b) For the year ended December 31, 2018, the Company has revised the December 31, 2017, estimates of the income tax effects of the Tax Act, in accordance with SAB 118. See the Statutory Rate Reconciliation section below for additional information on the Tax Act's impact on income tax expense . Duke Energy Income from Continuing Operations before Income Taxes Years Ended December 31, (in millions) 2020 2019 2018 Domestic $ 826 $ 4,053 $ 3,018 Foreign 13 44 55 Income from continuing operations before income taxes $ 839 $ 4,097 $ 3,073 Statutory Rate Reconciliation The following tables present a reconciliation of income tax expense at the U.S. federal statutory tax rate to the actual tax expense from continuing operations. Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Income tax expense, computed at the statutory rate of 21% $ 176 $ 219 $ 243 $ 80 $ 204 $ 62 $ 103 $ 61 State income tax, net of federal income tax effect (80) (40) 4 (25) 39 2 19 (12) Amortization of excess deferred income tax (276) (82) (118) (68) (49) (20) (36) (21) AFUDC equity income (48) (13) (9) (6) (3) (2) (4) (10) AFUDC equity depreciation 103 19 10 5 5 1 4 — Noncontrolling Interests 62 — — — — — — — Renewable energy PTCs (110) — — — — — — — Other tax credits (37) (13) (16) (14) (2) (1) (3) (2) Tax true up (12) (3) 1 (5) 5 — (1) 1 Other items, net (14) 1 (2) (3) (1) 1 2 1 Income tax (benefit) expense from continuing operations $ (236) $ 88 $ 113 $ (36) $ 198 $ 43 $ 84 $ 18 Effective tax rate (28.1) % 8.4 % 9.7 % (9.5) % 20.4 % 14.6 % 17.1 % 6.2 % Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Income tax expense, computed at the statutory rate of 21% $ 860 $ 360 $ 332 $ 202 $ 178 $ 59 $ 120 $ 51 State income tax, net of federal income tax effect (22) (19) 8 (17) 35 3 22 2 Amortization of excess deferred income tax (121) (29) (64) (10) (54) (12) (6) (10) AFUDC equity income (52) (9) (14) (13) (1) (3) (3) — AFUDC equity depreciation 34 19 10 5 5 1 4 — Renewable energy PTCs (120) — — — — — — — Other tax credits (23) (11) (9) (7) (2) (1) (1) (1) Tax true up (64) (9) (8) (3) (5) (7) (1) — Other items, net 27 9 (2) — (1) — (1) 1 Income tax expense from continuing operations $ 519 $ 311 $ 253 $ 157 $ 155 $ 40 $ 134 $ 43 Effective tax rate 12.7 % 18.1 % 16.0 % 16.3 % 18.3 % 14.3 % 23.5 % 17.6 % Year Ended December 31, 2018 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Income tax expense, computed at the statutory rate of 21% $ 645 $ 288 $ 263 $ 174 $ 137 $ 46 $ 109 $ 35 State income tax, net of federal income tax effect 30 14 13 (17) 28 2 20 4 Amortization of excess deferred income tax (61) — (55) (1) (54) (3) (2) — AFUDC equity income (42) (15) (22) (12) (10) (2) (2) — AFUDC equity depreciation 31 18 9 5 4 1 4 — Renewable energy PTCs (129) — — — — — — — Other tax credits (28) (7) (13) (5) (8) (1) (1) (3) Tax Act (a) 20 1 25 19 — 2 — — Other items, net (18) 4 (2) (3) 4 (2) — 1 Income tax expense from continuing operations $ 448 $ 303 $ 218 $ 160 $ 101 $ 43 $ 128 $ 37 Effective tax rate 14.6 % 22.1 % 17.4 % 19.3 % 15.4 % 19.6 % 24.6 % 22.3 % (a) For the year ended December 31, 2018, the Company revised the December 31, 2017, estimates of the income tax effects of the Tax Act, in accordance with SAB 118. Amounts primarily include but are not limited to items that are excluded for ratemaking purposes related certain wholesale fixed-rate contracts, remeasurement of nonregulated net deferred tax liabilities, Federal NOLs, and valuation allowance on foreign tax credits. Valuation allowances have been established for certain state NOL carryforwards and state income tax credits that reduce deferred tax assets to an amount that will be realized on a more-likely-than-not basis. The net change in the total valuation allowance is included in State income tax, net of federal income tax effect, in the above tables. Valuation allowances have been established for foreign tax credits that reduce deferred tax assets to an amount that will be realized on a more-likely-than-not basis. The net change in the total valuation allowance is included in Tax Act in the above tables. DEFERRED TAXES Net Deferred Income Tax Liability Components December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Deferred credits and other liabilities $ 286 $ 85 $ 87 $ 67 $ 18 $ 21 $ 7 $ 38 Lease obligations 515 96 208 120 87 5 16 5 Pension, post-retirement and other employee benefits 236 (30) 68 24 38 16 26 (5) Progress Energy merger purchase accounting adjustments (a) 441 — — — — — — — Tax credits and NOL carryforwards 3,909 285 508 179 282 16 183 29 Regulatory liabilities and deferred credits — 11 — — — 18 — — Investments and other assets — — — — — 7 — Other 93 8 14 9 4 7 1 8 Valuation allowance (586) — — — — — — — Total deferred income tax assets 4,894 455 885 399 429 90 233 75 Investments and other assets (2,267) (1,127) (669) (507) (164) — (14) (48) Accelerated depreciation rates (10,729) (3,170) (3,868) (1,778) (2,124) (1,071) (1,433) (844) Regulatory assets and deferred debits, net (1,142) — (744) (412) (332) — (14) (4) Total deferred income tax liabilities (14,138) (4,297) (5,281) (2,697) (2,620) (1,071) (1,461) (896) Net deferred income tax liabilities $ (9,244) $ (3,842) $ (4,396) $ (2,298) $ (2,191) $ (981) $ (1,228) $ (821) (a) Primarily related to lease obligations and debt fair value adjustments. The following table presents the expiration of tax credits and NOL carryforwards. December 31, 2020 (in millions) Amount Expiration Year General Business Credits $ 2,033 2024 — 2040 Federal NOL carryforwards (a) (f) 154 2024 — Indefinite Capital loss carryforward (e) 85 2024 State carryforwards and credits (b) (f) 340 2021 — Indefinite Foreign NOL carryforwards (c) 12 2027 — 2037 Foreign Tax Credits (d) 1,272 2024 — 2027 Charitable contribution carryforwards 13 2025 Total tax credits and NOL carryforwards $ 3,909 (a) A valuation allowance of $4 million has been recorded on the Federal NOL carryforwards, as presented in the Net Deferred Income Tax Liability Components table. (b) A valuation allowance of $97 million has been recorded on the state NOL and attribute carryforwards, as presented in the Net Deferred Income Tax Liability Components table. (c) A valuation allowance of $12 million has been recorded on the foreign NOL carryforwards, as presented in the Net Deferred Income Tax Liability Components table. (d) A valuation allowance of $388 million has been recorded on the foreign tax credits, as presented in the Net Deferred Income Tax Liability Components table. (e) A valuation allowance of $85 million has been recorded on the Federal capital loss carryforward, as presented in the Net Deferred Income Tax Liability Components table. (f) Indefinite carryforward for Federal NOLs, and NOLs for states that have adopted the Tax Act's NOL provisions, generated in tax years beginning after December 31, 2017. December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Deferred credits and other liabilities $ 125 $ 24 $ 25 $ 49 $ — $ 14 $ 5 $ 22 Lease obligations 462 72 193 92 102 5 17 6 Pension, post-retirement and other employee benefits 303 (5) 88 38 44 17 27 (3) Progress Energy merger purchase accounting adjustments (a) 389 — — — — — — — Tax credits and NOL carryforwards 3,925 262 486 176 253 16 176 19 Regulatory liabilities and deferred credits — — — — — 36 52 42 Investments and other assets — — — — — 10 — 2 Other 97 5 8 3 2 8 1 6 Valuation allowance (587) — — — — — — — Total deferred income tax assets 4,714 358 800 358 401 106 278 94 Investments and other assets (1,664) (981) (577) (390) (190) — (12) — Accelerated depreciation rates (10,813) (3,254) (3,798) (1,918) (1,913) (1,028) (1,416) (802) Regulatory assets and deferred debits, net (1,115) (44) (887) (438) (477) — — — Total deferred income tax liabilities (13,592) (4,279) (5,262) (2,746) (2,580) (1,028) (1,428) (802) Net deferred income tax liabilities $ (8,878) $ (3,921) $ (4,462) $ (2,388) $ (2,179) $ (922) $ (1,150) $ (708) (a) Primarily related to finance lease obligations and debt fair value adjustments. UNRECOGNIZED TAX BENEFITS The following tables present changes to unrecognized tax benefits. Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Unrecognized tax benefits – January 1 $ 126 $ 8 $ 9 $ 6 $ 3 $ 1 $ 1 $ 4 Gross decreases – tax positions in prior periods (2) — — — — — — — Gross increases – current period tax positions 4 2 1 — — — — — Reduction due to lapse of statute of limitations (3) — — — — — — (3) Total changes (1) 2 1 — — — — (3) Unrecognized tax benefits – December 31 $ 125 $ 10 $ 10 $ 6 $ 3 $ 1 $ 1 $ 1 Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Unrecognized tax benefits – January 1 $ 24 $ 6 $ 9 $ 6 $ 3 $ 1 $ 1 $ 4 Unrecognized tax benefits increases 105 2 1 1 — — — — Gross decreases – tax positions in prior periods (3) — (1) (1) — — — — Total changes 102 2 — — — — — — Unrecognized tax benefits – December 31 $ 126 $ 8 $ 9 $ 6 $ 3 $ 1 $ 1 $ 4 Year Ended December 31, 2018 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Unrecognized tax benefits – January 1 $ 25 $ 5 $ 5 $ 5 $ 5 $ 1 $ 1 $ 3 Unrecognized tax benefits increases (decreases) Gross decreases – tax positions in prior periods (2) (1) — — (4) — — — Gross increases – tax positions in prior periods 7 2 4 1 2 — — 1 Decreases due to settlements (6) — — — — — — — Total changes (1) 1 4 1 (2) — — 1 Unrecognized tax benefits – December 31 $ 24 $ 6 $ 9 $ 6 $ 3 $ 1 $ 1 $ 4 The following table includes additional information regarding the Duke Energy Registrants' unrecognized tax benefits at December 31, 2020. Duke Energy Registrants do not anticipate a material increase or decrease in unrecognized tax benefits within the next 12 months. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Amount that if recognized, would affect the effective tax rate or regulatory liability (a) $ 122 $ 10 $ 10 $ 6 $ 3 $ 1 $ 1 $ 1 (a) The Duke Energy Registrants are unable to estimate the specific amounts that would affect the ETR versus the regulatory liability. Duke Energy and its subsidiaries are no longer subject to U.S. federal examination for years before 2016. With few exceptions, Duke Energy and its subsidiaries are no longer subject to state, local or non-U.S. income tax examinations by tax authorities for years before 2016.

Other Income and Expenses, Net

Other Income and Expenses, Net	12 Months Ended
	Dec. 31, 2020
Other Income and Expenses [Abstract]
Other Income and Expenses, Net	OTHER INCOME AND EXPENSES, NET The components of Other income and expenses, net on the Consolidated Statements of Operations are as follows. Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Interest income $ 32 $ 4 $ 8 $ 2 $ 6 $ 4 $ 6 $ 17 AFUDC equity 154 62 42 29 12 7 23 19 Post in-service equity returns 27 17 8 8 — 1 1 — Nonoperating income, other 240 94 71 36 35 4 7 15 Other income and expense, net $ 453 $ 177 $ 129 $ 75 $ 53 $ 16 $ 37 $ 51 Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Interest income $ 31 $ 1 $ 11 $ — $ 11 $ 10 $ 10 $ 1 AFUDC equity 139 42 66 60 6 13 18 — Post in-service equity returns 29 20 7 7 — 1 — — Nonoperating income, other 231 88 57 33 31 — 13 19 Other income and expense, net $ 430 $ 151 $ 141 $ 100 $ 48 $ 24 $ 41 $ 20 Year Ended December 31, 2018 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Interest income $ 20 $ 1 $ 18 $ 1 $ 18 $ 7 $ 9 $ 1 AFUDC equity 221 73 104 57 47 11 32 — Post in-service equity returns 15 9 5 5 — 1 — — Nonoperating income, other 143 70 38 24 21 4 4 13 Other income and expense, net $ 399 $ 153 $ 165 $ 87 $ 86 $ 23 $ 45 $ 14

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS For information on subsequent events related to the sale of a minority interest in Duke Energy Indiana and regulatory matters, see Notes 1 and 3, respectively. In February 2021, a severe winter storm impacted certain Commercial Renewables assets in Texas. Extreme weather conditions limited the ability for these solar and wind facilities to generate and sell electricity into the Electric Reliability Council of Texas market. The financial impact of the storm is estimated to be between approximately $75 million and $100 million on a pre-tax basis.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policy)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Nature of Operations and Basis of Consolidation	Nature of Operations and Basis of Consolidation Duke Energy is an energy company headquartered in Charlotte, North Carolina, subject to regulation by the FERC and other regulatory agencies listed below. Duke Energy operates in the U.S. primarily through its direct and indirect subsidiaries. Certain Duke Energy subsidiaries are also subsidiary registrants, including Duke Energy Carolinas; Progress Energy; Duke Energy Progress; Duke Energy Florida; Duke Energy Ohio; Duke Energy Indiana and Piedmont. When discussing Duke Energy’s consolidated financial information, it necessarily includes the results of its separate Subsidiary Registrants, which along with Duke Energy, are collectively referred to as the Duke Energy Registrants. The information in these combined notes relates to each of the Duke Energy Registrants as noted in the Index to Combined Notes to Consolidated Financial Statements. However, none of the Subsidiary Registrants make any representation as to information related solely to Duke Energy or the Subsidiary Registrants of Duke Energy other than itself. These Consolidated Financial Statements include, after eliminating intercompany transactions and balances, the accounts of the Duke Energy Registrants and subsidiaries or VIEs where the respective Duke Energy Registrants have control. See Note 17 for additional information on VIEs. These Consolidated Financial Statements also reflect the Duke Energy Registrants’ proportionate share of certain jointly owned generation and transmission facilities. See Note 8 for additional information on joint ownership. Substantially all of the Subsidiary Registrants' operations qualify for regulatory accounting. Duke Energy Carolinas is a regulated public utility primarily engaged in the generation, transmission, distribution and sale of electricity in portions of North Carolina and South Carolina. Duke Energy Carolinas is subject to the regulatory provisions of the NCUC, PSCSC, NRC and FERC. Progress Energy is a public utility holding company, which conducts operations through its wholly owned subsidiaries, Duke Energy Progress and Duke Energy Florida. Progress Energy is subject to regulation by FERC and other regulatory agencies listed below. Duke Energy Progress is a regulated public utility primarily engaged in the generation, transmission, distribution and sale of electricity in portions of North Carolina and South Carolina. Duke Energy Progress is subject to the regulatory provisions of the NCUC, PSCSC, NRC and FERC. Duke Energy Florida is a regulated public utility primarily engaged in the generation, transmission, distribution and sale of electricity in portions of Florida. Duke Energy Florida is subject to the regulatory provisions of the FPSC, NRC and FERC. Duke Energy Ohio is a regulated public utility primarily engaged in the transmission and distribution of electricity in portions of Ohio and Kentucky, the generation and sale of electricity in portions of Kentucky and the transportation and sale of natural gas in portions of Ohio and Kentucky. Duke Energy Ohio conducts competitive auctions for retail electricity supply in Ohio whereby the energy price is recovered from retail customers and recorded in Operating Revenues on the Consolidated Statements of Operations and Comprehensive Income. Operations in Kentucky are conducted through its wholly owned subsidiary, Duke Energy Kentucky. References herein to Duke Energy Ohio collectively include Duke Energy Ohio and its subsidiaries, unless otherwise noted. Duke Energy Ohio is subject to the regulatory provisions of the PUCO, KPSC and FERC. Duke Energy Indiana is a regulated public utility primarily engaged in the generation, transmission, distribution and sale of electricity in portions of Indiana. Duke Energy Indiana is subject to the regulatory provisions of the IURC and FERC. Piedmont is a regulated public utility primarily engaged in the distribution of natural gas in portions of North Carolina, South Carolina and Tennessee. Piedmont is subject to the regulatory provisions of the NCUC, PSCSC, TPUC and FERC. Certain prior year amounts have been reclassified to conform to the current year presentation.
Discontinued Operations	Discontinued OperationsDuke Energy has elected to present cash flows of discontinued operations combined with cash flows of continuing operations. Unless otherwise noted, the notes to these consolidated financial statements exclude amounts related to discontinued operations for all periods presented. For the years ended December 31, 2020, 2019 and 2018, the Income (Loss) From Discontinued Operations, net of tax on Duke Energy's Consolidated Statements of Operations is entirely attributable to controlling interest.
Noncontrolling Interest	Noncontrolling Interest Duke Energy maintains a controlling financial interest in certain less than wholly owned nonregulated subsidiaries. As a result, Duke Energy consolidates these subsidiaries and presents the third-party investors' portion of Duke Energy's net income (loss), net assets and comprehensive income (loss) as noncontrolling interest. Noncontrolling interest is included as a component of equity on the Consolidated Balance Sheet. Several operating agreements of Duke Energy's subsidiaries with noncontrolling interest are subject to allocations of tax attributes and cash flows in accordance with contractual agreements that vary throughout the lives of the subsidiaries. Therefore, Duke Energy and the other investors' (the owners) interests in the subsidiaries are not fixed, and the subsidiaries apply the HLBV method in allocating income or loss and other comprehensive income or loss (all measured on a pretax basis) to the owners. The HLBV method measures the amounts that each owner would hypothetically claim at each balance sheet reporting date, including tax benefits realized by the owners, most of which is over the IRS recapture period, upon a hypothetical liquidation of the subsidiary at the net book value of its underlying assets. The change in the amount that each owner would hypothetically receive at the reporting date compared to the amount it would have received on the previous reporting date represents the amount of income or loss allocated to each owner for the reporting period.
Acquisitions	Acquisitions The Duke Energy Registrants consolidate assets and liabilities from acquisitions as of the purchase date and include earnings from acquisitions in consolidated earnings after the purchase date.
Use of Estimates	Use of Estimates In preparing financial statements that conform to GAAP, the Duke Energy Registrants must make estimates and assumptions that affect the reported amounts of assets and liabilities, the reported amounts of revenues and expenses and the disclosure of contingent assets and liabilities at the date of the financial statements. Actual results could differ from those estimates.
Regulatory Accounting	Regulatory Accounting The majority of the Duke Energy Registrants’ operations are subject to price regulation for the sale of electricity and natural gas by state utility commissions or FERC. When prices are set on the basis of specific costs of the regulated operations and an effective franchise is in place such that sufficient natural gas or electric services can be sold to recover those costs, the Duke Energy Registrants apply regulatory accounting. Regulatory accounting changes the timing of the recognition of costs or revenues relative to a company that does not apply regulatory accounting. As a result, regulatory assets and regulatory liabilities are recognized on the Consolidated Balance Sheets. Regulatory assets and liabilities are amortized consistent with the treatment of the related cost in the ratemaking process. Regulatory assets are reviewed for recoverability each reporting period. If a regulatory asset is no longer deemed probable of recovery, the deferred cost is charged to earnings. See Note 3 for further information. Regulatory accounting rules also require recognition of a disallowance (also called "impairment") loss if it becomes probable that part of the cost of a plant under construction (or a recently completed plant or an abandoned plant) will be disallowed for ratemaking purposes and a reasonable estimate of the amount of the disallowance can be made. For example, if a cost cap is set for a plant still under construction, the amount of the disallowance is a result of a judgment as to the ultimate cost of the plant. These disallowances can require judgments on allowed future rate recovery.
Regulated Fuel Costs and Purchased Power	The Duke Energy Registrants utilize cost-tracking mechanisms, commonly referred to as fuel adjustment clauses or PGA clauses. These clauses allow for the recovery of fuel and fuel-related costs, portions of purchased power, natural gas costs and hedging costs through surcharges on customer rates. The difference between the costs incurred and the surcharge revenues is recorded either as an adjustment to Operating Revenues, Operating Expenses – Fuel used in electric generation or Operating Expenses – Cost of natural gas on the Consolidated Statements of Operations, with an off-setting impact on regulatory assets or liabilities
Cash, Cash Equivalents and Restricted Cash	Cash, Cash Equivalents and Restricted CashAll highly liquid investments with maturities of three months or less at the date of acquisition are considered cash equivalents. Duke Energy, Progress Energy and Duke Energy Florida have restricted cash balances related primarily to collateral assets, escrow deposits and VIEs. See Note 17 for additional information. Restricted cash amounts are included in Other within Current Assets and Other Noncurrent Assets on the Consolidated Balance Sheets.
Inventory	InventoryInventory related to regulated operations is valued at historical cost. Inventory related to nonregulated operations is valued at the lower of cost or market. Inventory is charged to expense or capitalized to property, plant and equipment when issued, primarily using the average cost method. Excess or obsolete inventory is written down to the lower of cost or net realizable value. Once inventory has been written down, it creates a new cost basis for the inventory that is not subsequently written up. Provisions for inventory write-offs were not material at December 31, 2020, and 2019, respectively.
Investments in Debt and Equity Securities	Investments in Debt and Equity SecuritiesThe Duke Energy Registrants classify investments in equity securities as FV-NI and investments in debt securities as AFS. Both categories are recorded at fair value on the Consolidated Balance Sheets. Realized and unrealized gains and losses on securities classified as FV-NI are reported through net income. Unrealized gains and losses for debt securities classified as AFS are included in AOCI until realized, unless it is determined the carrying value of an investment has a credit loss. For certain investments of regulated operations, such as substantially all of the NDTF, realized and unrealized gains and losses (including any credit losses) on debt securities are recorded as a regulatory asset or liability. The credit loss portion of debt securities of nonregulated operations are included in earnings. Investments in debt and equity securities are classified as either current or noncurrent based on management’s intent and ability to sell these securities, taking into consideration current market liquidity.
Goodwill and Intangible Assets	Goodwill Duke Energy, Progress Energy, Duke Energy Ohio and Piedmont perform annual goodwill impairment tests as of August 31 each year at the reporting unit level, which is determined to be a business segment or one level below. Duke Energy, Progress Energy, Duke Energy Ohio and Piedmont update these tests between annual tests if events or circumstances occur that would more likely than not reduce the fair value of a reporting unit below its carrying value. See Note 11 for further information. Intangible Assets Intangible assets are included in Other in Other Noncurrent Assets on the Consolidated Balance Sheets. Generally, intangible assets are amortized using an amortization method that reflects the pattern in which the economic benefits of the intangible asset are consumed or on a straight-line basis if that pattern is not readily determinable. Amortization of intangibles is reflected in Depreciation and amortization on the Consolidated Statements of Operations. Intangible assets are subject to impairment testing and if impaired, the carrying value is accordingly reduced.
Long-Lived Asset Impairments	Long-Lived Asset Impairments The Duke Energy Registrants evaluate long-lived assets, excluding goodwill, for impairment when circumstances indicate the carrying value of those assets may not be recoverable. An impairment exists when a long-lived asset’s carrying value exceeds the estimated undiscounted cash flows expected to result from the use and eventual disposition of the asset. The estimated cash flows may be based on alternative expected outcomes that are probability weighted. If the carrying value of the long-lived asset is not recoverable based on these estimated future undiscounted cash flows, the carrying value of the asset is written down to its then current estimated fair value and an impairment charge is recognized. The Duke Energy Registrants assess fair value of long-lived assets using various methods, including recent comparable third-party sales, internally developed discounted cash flow analysis and analysis from outside advisors. Triggering events to reassess cash flows may include, but are not limited to, significant changes in commodity prices, the condition of an asset or management’s interest in selling the asset.
Equity Method Investment Impairments	Equity Method Investment Impairments Investments in affiliates that are not controlled by Duke Energy, but over which it has significant influence, are accounted for using the equity method. Equity method investments are assessed for impairment whenever events or changes in circumstances indicate that the carrying amount of the investment may not be recoverable. If the decline in value is considered to be other than temporary, the investment is written down to its estimated fair value, which establishes a new cost basis in the investment. Impairment assessments use a discounted cash flow income approach and include consideration of the severity and duration of any decline in the fair value of the investments. The estimated cash flows may be based on alternative expected outcomes that are probability weighted. Key inputs that involve estimates and significant management judgment include cash flow projections, selection of a discount rate, probability weighting of potential outcomes, and whether any decline in value is considered temporary.
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment are stated at the lower of depreciated historical cost net of any disallowances or fair value, if impaired. The Duke Energy Registrants capitalize all construction-related direct labor and material costs, as well as indirect construction costs such as general engineering, taxes and financing costs. See “Allowance for Funds Used During Construction and Interest Capitalized” for information on capitalized financing costs. Costs of renewals and betterments that extend the useful life of property, plant and equipment are also capitalized. The cost of repairs, replacements and major maintenance projects, which do not extend the useful life or increase the expected output of the asset, are expensed as incurred. Depreciation is generally computed over the estimated useful life of the asset using the composite straight-line method. Depreciation studies are conducted periodically to update composite rates and are approved by state utility commissions and/or the FERC when required. The composite weighted average depreciation rates, excluding nuclear fuel, are included in the table that follows. Years Ended December 31, 2020 2019 2018 Duke Energy 3.0 % 3.1 % 3.0 % Duke Energy Carolinas 2.8 % 2.8 % 2.8 % Progress Energy 3.2 % 3.1 % 2.9 % Duke Energy Progress 3.1 % 3.1 % 2.9 % Duke Energy Florida 3.3 % 3.1 % 3.0 % Duke Energy Ohio 2.9 % 2.6 % 2.8 % Duke Energy Indiana 3.5 % 3.3 % 3.3 % Piedmont 2.3 % 2.4 % 2.5 % In general, when the Duke Energy Registrants retire regulated property, plant and equipment, the original cost plus the cost of retirement, less salvage value and any depreciation already recognized, is charged to accumulated depreciation. However, when it becomes probable the asset will be retired substantially in advance of its original expected useful life or is abandoned, the cost of the asset and the corresponding accumulated depreciation is recognized as a separate asset. If the asset is still in operation, the net amount is classified as Generation facilities to be retired, net on the Consolidated Balance Sheets. If the asset is no longer operating, the net amount is classified in Regulatory assets on the Consolidated Balance Sheets if deemed recoverable (see discussion of long-lived asset impairments above). The carrying value of the asset is based on historical cost if the Duke Energy Registrants are allowed to recover the remaining net book value and a return equal to at least the incremental borrowing rate. If not, an impairment is recognized to the extent the net book value of the asset exceeds the present value of future revenues discounted at the incremental borrowing rate. When the Duke Energy Registrants sell entire regulated operating units, or retire or sell nonregulated properties, the original cost and accumulated depreciation and amortization balances are removed from Property, Plant and Equipment on the Consolidated Balance Sheets. Any gain or loss is recorded in earnings, unless otherwise required by the applicable regulatory body. See Note 10 for additional information.
Leases	Leases Duke Energy determines if an arrangement is a lease at contract inception based on whether the arrangement involves the use of a physically distinct identified asset and whether Duke Energy has the right to obtain substantially all of the economic benefits from the use of the asset throughout the period as well as the right to direct the use of the asset. As a policy election, Duke Energy does not evaluate arrangements with initial contract terms of less than one year as leases. Operating leases are included in Operating lease ROU assets, net, Other current liabilities and Operating lease liabilities on the Consolidated Balance Sheets. Finance leases are included in Property, plant and equipment, Current maturities of long-term debt and Long-Term Debt on the Consolidated Balance Sheets. For lessee and lessor arrangements, Duke Energy has elected a policy to not separate lease and non-lease components for all asset classes. For lessor arrangements, lease and non-lease components are only combined under one arrangement and accounted for under the lease accounting framework if the non-lease components are not the predominant component of the arrangement and the lease component would be classified as an operating lease.
Leases	Leases Duke Energy determines if an arrangement is a lease at contract inception based on whether the arrangement involves the use of a physically distinct identified asset and whether Duke Energy has the right to obtain substantially all of the economic benefits from the use of the asset throughout the period as well as the right to direct the use of the asset. As a policy election, Duke Energy does not evaluate arrangements with initial contract terms of less than one year as leases. Operating leases are included in Operating lease ROU assets, net, Other current liabilities and Operating lease liabilities on the Consolidated Balance Sheets. Finance leases are included in Property, plant and equipment, Current maturities of long-term debt and Long-Term Debt on the Consolidated Balance Sheets. For lessee and lessor arrangements, Duke Energy has elected a policy to not separate lease and non-lease components for all asset classes. For lessor arrangements, lease and non-lease components are only combined under one arrangement and accounted for under the lease accounting framework if the non-lease components are not the predominant component of the arrangement and the lease component would be classified as an operating lease.
Nuclear Fuel	Nuclear Fuel Nuclear fuel is classified as Property, Plant and Equipment on the Consolidated Balance Sheets. Nuclear fuel in the front-end fuel processing phase is considered work in progress and not amortized until placed in service. Amortization of nuclear fuel is included within Fuel used in electric generation and purchased power on the Consolidated Statements of Operations. Amortization is recorded using the units-of-production method.
Allowance for Funds Used During Construction and Interest Capitalized	Allowance for Funds Used During Construction and Interest Capitalized For regulated operations, the debt and equity costs of financing the construction of property, plant and equipment are reflected as AFUDC and capitalized as a component of the cost of property, plant and equipment. AFUDC equity is reported on the Consolidated Statements of Operations as non-cash income in Other income and expenses, net. AFUDC debt is reported as a non-cash offset to Interest Expense. After construction is completed, the Duke Energy Registrants are permitted to recover these costs through their inclusion in rate base and the corresponding subsequent depreciation or amortization of those regulated assets. AFUDC equity, a permanent difference for income taxes, reduces the ETR when capitalized and increases the ETR when depreciated or amortized. See Note 23 for additional information. For nonregulated operations, interest is capitalized during the construction phase with an offsetting non-cash credit to Interest Expense on the Consolidated Statements of Operations.
Asset Retirement Obligations	Asset Retirement Obligations AROs are recognized for legal obligations associated with the retirement of property, plant and equipment. Substantially all AROs are related to regulated operations. When recording an ARO, the present value of the projected liability is recognized in the period in which it is incurred, if a reasonable estimate of fair value can be made. The liability is accreted over time. For operating plants, the present value of the liability is added to the cost of the associated asset and depreciated over the remaining life of the asset. For retired plants, the present value of the liability is recorded as a regulatory asset unless determined not to be probable of recovery. The present value of the initial obligation and subsequent updates are based on discounted cash flows, which include estimates regarding timing of future cash flows, selection of discount rates and cost escalation rates, among other factors. These estimates are subject to change. Depreciation expense is adjusted prospectively for any changes to the carrying amount of the associated asset. The Duke Energy Registrants receive amounts to fund the cost of the ARO for regulated operations through a combination of regulated revenues and earnings on the NDTF. As a result, amounts recovered in regulated revenues, earnings on the NDTF, accretion expense and depreciation of the associated asset are netted and deferred as a regulatory asset or liability.
Revenue Recognition	Revenue Recognition Duke Energy recognizes revenue as customers obtain control of promised goods and services in an amount that reflects consideration expected in exchange for those goods or services. Generally, the delivery of electricity and natural gas results in the transfer of control to customers at the time the commodity is delivered and the amount of revenue recognized is equal to the amount billed to each customer, including estimated volumes delivered when billings have not yet occurred. See Note 18 for further information.
Derivatives and Hedging	Derivatives and Hedging Derivative and non-derivative instruments may be used in connection with commodity price and interest rate activities, including swaps, futures, forwards and options. All derivative instruments, except those that qualify for the NPNS exception, are recorded on the Consolidated Balance Sheets at fair value. Qualifying derivative instruments may be designated as either cash flow hedges or fair value hedges. Other derivative instruments (undesignated contracts) either have not been designated or do not qualify as hedges. The effective portion of the change in the fair value of cash flow hedges is recorded in AOCI. The effective portion of the change in the fair value of a fair value hedge is offset in net income by changes in the hedged item. For activity subject to regulatory accounting, gains and losses on derivative contracts are reflected as regulatory assets or liabilities and not as other comprehensive income or current period income. As a result, changes in fair value of these derivatives have no immediate earnings impact. Formal documentation, including transaction type and risk management strategy, is maintained for all contracts accounted for as a hedge. At inception and at least every three months thereafter, the hedge contract is assessed to see if it is highly effective in offsetting changes in cash flows or fair values of hedged items.
Captive Insurance Reserves	Captive Insurance Reserves Duke Energy has captive insurance subsidiaries that provide coverage, on an indemnity basis, to the Subsidiary Registrants as well as certain third parties, on a limited basis, for financial losses, primarily related to property, workers’ compensation and general liability. Liabilities include provisions for estimated losses incurred but not reported (IBNR), as well as estimated provisions for known claims. IBNR reserve estimates are primarily based upon historical loss experience, industry data and other actuarial assumptions. Reserve estimates are adjusted in future periods as actual losses differ from experience.
Unamortized Debt Premium, Discount and Expense	Unamortized Debt Premium, Discount and Expense Premiums, discounts and expenses incurred with the issuance of outstanding long-term debt are amortized over the term of the debt issue. The gain or loss on extinguishment associated with refinancing higher-cost debt obligations in the regulated operations is amortized over the remaining life of the original instrument. Amortization expense is recorded as Interest Expense in the Consolidated Statements of Operations and is reflected as Depreciation, amortization and accretion within Net cash provided by operating activities on the Consolidated Statements of Cash Flows. Premiums, discounts and expenses are presented as an adjustment to the carrying value of the debt amount and included in Long-Term Debt on the Consolidated Balance Sheets presented.
Preferred Stock	Preferred Stock Preferred stock is reviewed to determine the appropriate balance sheet classification and embedded features, such as call options, are evaluated to determine if they should be bifurcated and accounted for separately. Costs directly related to the issuance of preferred stock is recorded as a reduction of the proceeds received. The liability for the dividend is recognized when declared. The accumulated dividends on the cumulative preferred stock is recognized to net income available to Duke Energy Corporation in the EPS calculation. See Note 19 for further information.
Loss Contingencies and Environmental Liabilities	Loss Contingencies and Environmental Liabilities Contingent losses are recorded when it is probable a loss has occurred and can be reasonably estimated. When a range of the probable loss exists and no amount within the range is a better estimate than any other amount, the minimum amount in the range is recorded. Unless otherwise required by GAAP, legal fees are expensed as incurred. Environmental liabilities are recorded on an undiscounted basis when environmental remediation or other liabilities become probable and can be reasonably estimated. Environmental expenditures related to past operations that do not generate current or future revenues are expensed. Environmental expenditures related to operations that generate current or future revenues are expensed or capitalized, as appropriate. Certain environmental expenditures receive regulatory accounting treatment and are recorded as regulatory assets.
Pension and Other Post-Retirement Benefit Plans	Pension and Other Post-Retirement Benefit PlansDuke Energy maintains qualified, non-qualified and other post-retirement benefit plans. Eligible employees of the Subsidiary Registrants participate in the respective qualified, non-qualified and other post-retirement benefit plans and the Subsidiary Registrants are allocated their proportionate share of benefit costs.
Severance and Special Termination Benefits	Severance and Special Termination BenefitsDuke Energy has severance plans under which in general, the longer a terminated employee worked prior to termination the greater the amount of severance benefits. A liability for involuntary severance is recorded once an involuntary severance plan is committed to by management if involuntary severances are probable and can be reasonably estimated. For involuntary severance benefits incremental to its ongoing severance plan benefits, the fair value of the obligation is expensed at the communication date if there are no future service requirements or over the required future service period. Duke Energy also offers special termination benefits under voluntary severance programs. Special termination benefits are recorded immediately upon employee acceptance absent a significant retention period. Otherwise, the cost is recorded over the remaining service period. Employee acceptance of voluntary severance benefits is determined by management based on the facts and circumstances of the benefits being offered.
Guarantees	GuaranteesIf necessary, liabilities are recognized at the time of issuance or material modification of a guarantee for the estimated fair value of the obligation it assumes. Fair value is estimated using a probability weighted approach. The obligation is reduced over the term of the guarantee or related contract in a systematic and rational method as risk is reduced. Duke Energy recognizes a liability for the best estimate of its loss due to the nonperformance of the guaranteed party. This liability is recognized at the inception of a guarantee and is updated periodically.
Stock-Based Compensation	Stock-Based CompensationStock-based compensation represents costs related to stock-based awards granted to employees and Board of Directors members. Duke Energy recognizes stock-based compensation based upon the estimated fair value of awards, net of estimated forfeitures at the date of issuance. The recognition period for these costs begins at either the applicable service inception date or grant date and continues throughout the requisite service period. Compensation cost is recognized as expense or capitalized as a component of property, plant and equipment.
Income Taxes	Income Taxes Duke Energy and its subsidiaries file a consolidated federal income tax return and other state and foreign jurisdictional returns. The Subsidiary Registrants are parties to a tax-sharing agreement with Duke Energy. Income taxes recorded represent amounts the Subsidiary Registrants would incur as separate C-Corporations. Deferred income taxes have been provided for temporary differences between GAAP and tax bases of assets and liabilities because the differences create taxable or tax-deductible amounts for future periods. ITCs associated with regulated operations are deferred and amortized as a reduction of income tax expense over the estimated useful lives of the related properties. For ITCs associated with nonregulated operations see “Accounting for Renewable Energy Tax Credits.” Accumulated deferred income taxes are valued using the enacted tax rate expected to apply to taxable income in the periods in which the deferred tax asset or liability is expected to be settled or realized. In the event of a change in tax rates, deferred tax assets and liabilities are remeasured as of the enactment date of the new rate. To the extent that the change in the value of the deferred tax represents an obligation to customers, the impact of the remeasurement is deferred to a regulatory liability. Remaining impacts are recorded in income from continuing operations. Duke Energy's results of operations could be impacted if the estimate of the tax effect of reversing temporary differences is not reflective of actual outcomes, is modified to reflect new developments or interpretations of the tax law, revised to incorporate new accounting principles, or changes in the expected timing or manner of a reversal. Tax-related interest and penalties are recorded in Interest Expense and Other Income and Expenses, net in the Consolidated Statements of Operations.
Accounting for Renewable Energy Tax Credits	Accounting for Renewable Energy Tax Credits When Duke Energy receives ITCs on wind or solar facilities associated with its nonregulated operations, it reduces the basis of the property recorded on the Consolidated Balance Sheets by the amount of the ITC and, therefore, the ITC benefit is ultimately recognized in the statement of operations through reduced depreciation expense. Additionally, certain tax credits and government grants result in an initial tax depreciable base in excess of the book carrying value by an amount equal to one half of the ITC. Deferred tax benefits are recorded as a reduction to income tax expense in the period that the basis difference is created. When Duke Energy receives ITCs on wind or solar facilities associated with its regulated operations, the ITC is deferred and amortized as a reduction of income tax expense over the estimated useful lives of the related properties. Duke Energy receives PTCs on wind facilities that are recognized as electricity is produced and records related amounts as a reduction of income tax expense.
Excise Taxes	Excise TaxesCertain excise taxes levied by state or local governments are required to be paid even if not collected from the customer. These taxes are recognized on a gross basis. Taxes for which Duke Energy operates merely as a collection agent for the state and local government are accounted for on a net basis.
Dividend Restrictions and Unappropriated Retained Earnings	Dividend Restrictions and Unappropriated Retained Earnings Duke Energy does not have any current legal, regulatory or other restrictions on paying common stock dividends to shareholders. However, if Duke Energy were to defer dividend payments on the preferred stock, the declaration of common stock dividends would be prohibited. See Note 19 for more information. Additionally, as further described in Note 3, Duke Energy Carolinas, Duke Energy Progress, Duke Energy Ohio, Duke Energy Indiana and Piedmont have restrictions on paying dividends or otherwise advancing funds to Duke Energy due to conditions established by regulators in conjunction with merger transaction approvals. At December 31, 2020, and 2019, an insignificant amount of Duke Energy’s consolidated Retained earnings balance represents undistributed earnings of equity method investments.
New Accounting Standard	New Accounting Standards The following new accounting standard was adopted by Duke Energy Registrants in 2020. Credit Losses. In June 2016, the FASB issued new accounting guidance for credit losses. Duke Energy adopted the new accounting guidance for credit losses effective January 1, 2020, using the modified retrospective method of adoption, which does not require restatement of prior year results. Duke Energy did not adopt any practical expedients. Duke Energy recognizes allowances for credit losses based on management's estimate of losses expected to be incurred over the lives of certain assets or guarantees. Management monitors credit quality, changes in expected credit losses and the appropriateness of the allowance for credit losses on a forward-looking basis. Management reviews the risk of loss periodically as part of the existing assessment of collectability of receivables. Duke Energy reviews the credit quality of its counterparties as part of its regular risk management process and requires credit enhancements, such as deposits or letters of credit, as appropriate and as allowed by regulators. The following new accounting standard has been issued but not yet adopted by the Duke Energy Registrants as of December 31, 2020. Reference Rate Reform. In March 2020, the FASB issued new accounting guidance for reference rate reform. This guidance is elective and provides expedients to facilitate financial reporting for the anticipated transition away from the London Inter-bank Offered Rate (LIBOR) and other interbank reference rates by the end of 2021. The optional expedients are effective for modification of existing contracts or new arrangements executed between March 12, 2020, through December 31, 2022. Duke Energy has variable-rate debt and manages interest rate risk by entering into financial contracts including interest rate swaps that are generally indexed to LIBOR. Impacted financial arrangements extending beyond 2021 may require contractual amendment or termination to fully adapt to a post-LIBOR environment. Duke Energy is assessing these financial arrangements and is evaluating the use of optional expedients outlined in the new accounting guidance. Alternative index provisions are also being assessed and incorporated into new financial arrangements that extend beyond 2021. The full outcome of the transition away from LIBOR cannot be determined at this time, but is not expected to have a material impact on the financial statements.
Earnings Per Share	Basic EPS is computed by dividing net income available to Duke Energy common stockholders, as adjusted for distributed and undistributed earnings allocated to participating securities and accumulated preferred dividends, by the weighted average number of common shares outstanding during the period. Diluted EPS is computed by dividing net income available to Duke Energy common stockholders, as adjusted for distributed and undistributed earnings allocated to participating securities and accumulated preferred dividends, by the diluted weighted average number of common shares outstanding during the period. Diluted EPS reflects the potential dilution that could occur if securities or other agreements to issue common stock, such as equity forward sale agreements, were exercised or settled.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Schedule of Current and Noncurrent Assets and Liabilities	The following table provides a description of amounts included in Other within Current Assets or Current Liabilities that exceed 5% of total Current Assets or Current Liabilities on the Duke Energy Registrants' Consolidated Balance Sheets at either December 31, 2020, or 2019. December 31, (in millions) Location 2020 2019 Duke Energy Other accrued liabilities Current Liabilities $ 1,455 $ 604 Accrued compensation Current Liabilities 662 862 Duke Energy Carolinas Accrued compensation Current Liabilities $ 213 $ 271 Other accrued liabilities Current Liabilities 178 147 Progress Energy Customer deposits Current Liabilities $ 347 $ 354 Duke Energy Florida Customer deposits Current Liabilities $ 203 $ 209 Duke Energy Ohio Gas Storage Current Assets $ 21 $ — Duke Energy Indiana Income taxes receivable Current Assets $ 9 $ 44
Noncontrolling Divestitures And Allocated Losses	The following table presents cash received for the sale of noncontrolling interest and allocated losses to noncontrolling interest for the years ended December 31, 2020, and 2019. December 31, (in millions) 2020 2019 Noncontrolling Interest Capital Contributions Cash received for the sale of noncontrolling interest to tax equity members $ 426 $ 428 Cash received for the sale of noncontrolling interest to pro rata share members — 415 Total Noncontrolling Interest Capital Contributions $ 426 $ 843 Noncontrolling Interest Allocation of Income Allocated losses to noncontrolling tax equity members utilizing the HLBV method $ 271 $ 165 Allocated losses to noncontrolling members based on pro rata shares of ownership 24 12 Total Noncontrolling Interest Allocated Losses $ 295 $ 177
Schedule of Cash and Cash Equivalents	The following table presents the components of cash, cash equivalents and restricted cash included in the Consolidated Balance Sheets. December 31, 2020 December 31, 2019 Duke Duke Duke Progress Energy Duke Progress Energy Energy Energy Florida Energy Energy Florida Current Assets Cash and cash equivalents $ 259 $ 59 $ 11 $ 311 $ 48 $ 17 Other 194 39 39 222 39 39 Other Noncurrent Assets Other 103 102 — 40 39 — Total cash, cash equivalents and restricted cash $ 556 $ 200 $ 50 $ 573 $ 126 $ 56
Components of Inventory	The components of inventory are presented in the tables below. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Materials and supplies $ 2,312 $ 785 $ 999 $ 673 $ 325 $ 78 $ 307 $ 12 Coal 561 186 193 131 63 16 165 — Natural gas, oil and other 294 39 183 107 76 16 1 56 Total inventory $ 3,167 $ 1,010 $ 1,375 $ 911 $ 464 $ 110 $ 473 $ 68 December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Materials and supplies $ 2,297 $ 768 $ 1,038 $ 686 $ 351 $ 79 $ 318 $ 5 Coal 586 187 186 138 48 15 198 — Natural gas, oil and other 349 41 199 110 90 41 1 67 Total inventory $ 3,232 $ 996 $ 1,423 $ 934 $ 489 $ 135 $ 517 $ 72
Schedule of Property, Plant and Equipment	The composite weighted average depreciation rates, excluding nuclear fuel, are included in the table that follows. Years Ended December 31, 2020 2019 2018 Duke Energy 3.0 % 3.1 % 3.0 % Duke Energy Carolinas 2.8 % 2.8 % 2.8 % Progress Energy 3.2 % 3.1 % 2.9 % Duke Energy Progress 3.1 % 3.1 % 2.9 % Duke Energy Florida 3.3 % 3.1 % 3.0 % Duke Energy Ohio 2.9 % 2.6 % 2.8 % Duke Energy Indiana 3.5 % 3.3 % 3.3 % Piedmont 2.3 % 2.4 % 2.5 % The following tables summarize the property, plant and equipment for Duke Energy and its subsidiary registrants. December 31, 2020 Average Remaining Duke Duke Duke Duke Duke Useful Life Duke Energy Progress Energy Energy Energy Energy (in millions) (Years) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Land $ 2,046 $ 536 $ 908 $ 463 $ 445 $ 171 $ 118 $ 279 Plant – Regulated Electric generation, distribution and transmission 39 117,107 44,059 50,785 31,375 19,410 6,255 16,008 — Natural gas transmission and distribution 54 10,799 — — — — 3,136 — 7,663 Other buildings and improvements 36 2,038 740 459 197 262 374 300 165 Plant – Nonregulated Electric generation, distribution and transmission 27 5,444 — — — — — — — Other buildings and improvements 10 519 — — — — — — — Nuclear fuel 3,284 1,837 1,447 1,447 — — — — Equipment 15 2,608 620 759 498 261 385 238 122 Construction in process 6,645 1,645 2,013 709 1,304 407 409 581 Other 14 5,090 1,203 1,521 1,070 441 294 309 324 Total property, plant and equipment (a)(e) 155,580 50,640 57,892 35,759 22,123 11,022 17,382 9,134 Total accumulated depreciation – regulated (b)(c) (46,216) (17,453) (18,368) (12,801) (5,560) (3,013) (5,661) (1,749) Total accumulated depreciation – nonregulated (d)(e) (2,611) — — — — — — — Generation facilities to be retired, net 29 — 29 29 — — — — Total net property, plant and equipment $ 106,782 $ 33,187 $ 39,553 $ 22,987 $ 16,563 $ 8,009 $ 11,721 $ 7,385 (a) Includes finance leases of $832 million, $335 million, $416 million, $297 million, $119 million and $10 million at Duke Energy, Duke Energy Carolinas, Progress Energy, Duke Energy Progress, Duke Energy Florida and Duke Energy Indiana, respectively, primarily within Plant – Regulated. The Progress Energy, Duke Energy Progress and Duke Energy Florida amounts are net of $141 million, $24 million and $117 million, respectively, of accumulated amortization of finance leases. (b) Includes $1,832 million, $1,010 million, $822 million and $822 million of accumulated amortization of nuclear fuel at Duke Energy, Duke Energy Carolinas, Progress Energy and Duke Energy Progress, respectively. (c) Includes accumulated amortization of finance leases of $12 million, $23 million and $3 million at Duke Energy, Duke Energy Carolinas and Duke Energy Indiana, respectively. (d) Includes accumulated amortization of finance leases of $23 million at Duke Energy. (e) Includes gross property, plant and equipment cost of consolidated VIEs of $6,394 million and accumulated depreciation of consolidated VIEs of $1,242 million at Duke Energy. December 31, 2019 Average Remaining Duke Duke Duke Duke Duke Useful Life Duke Energy Progress Energy Energy Energy Energy (in millions) (Years) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Land $ 2,091 $ 520 $ 884 $ 449 $ 435 $ 150 $ 117 $ 388 Plant – Regulated Electric generation, distribution and transmission 39 111,739 42,723 48,142 30,018 18,124 5,838 15,032 — Natural gas transmission and distribution 54 9,839 — — — — 2,892 — 6,947 Other buildings and improvements 32 1,810 714 401 162 239 269 278 148 Plant – Nonregulated Electric generation, distribution and transmission 28 5,103 — — — — — — — Other buildings and improvements 9 488 — — — — — — — Nuclear fuel 3,253 1,891 1,362 1,362 — — — — Equipment 13 2,313 546 665 452 213 319 205 128 Construction in process 6,102 1,389 2,149 1,114 1,035 504 381 531 Other 13 4,916 1,139 1,467 1,046 411 269 292 304 Total property, plant and equipment (a)(e) 147,654 48,922 55,070 34,603 20,457 10,241 16,305 8,446 Total accumulated depreciation – regulated (b)(c) (43,419) (16,525) (17,159) (11,915) (5,236) (2,843) (5,233) (1,681) Total accumulated depreciation – nonregulated (d)(e) (2,354) — — — — — — — Generation facilities to be retired, net 246 — 246 246 — — — — Total net property, plant and equipment $ 102,127 $ 32,397 $ 38,157 $ 22,934 $ 15,221 $ 7,398 $ 11,072 $ 6,765 (a) Includes finance leases of $952 million, $211 million, $443 million, $308 million, $135 million, and $10 million at Duke Energy, Duke Energy Carolinas, Progress Energy, Duke Energy Progress, Duke Energy Florida and Duke Energy Indiana, respectively, primarily within Plant – Regulated. The Progress Energy, Duke Energy Progress and Duke Energy Florida amounts are net of $143 million, $17 million and $126 million, respectively, of accumulated amortization of finance leases. (b) Includes $1,807 million, $1,082 million, $725 million and $725 million of accumulated amortization of nuclear fuel at Duke Energy, Duke Energy Carolinas, Progress Energy and Duke Energy Progress, respectively. (c) Includes accumulated amortization of finance leases of $6 million, $13 million, and $3 million at Duke Energy, Duke Energy Carolinas and Duke Energy Indiana, respectively. (d) Includes accumulated amortization of finance leases of $20 million at Duke Energy. (e) Includes gross property, plant and equipment cost of consolidated VIEs of $5,747 million and accumulated depreciation of consolidated VIEs of $1,041 million at Duke Energy.
Schedule of Excise Taxes	Excise taxes accounted for on a gross basis within both Operating Revenues and Property and other taxes in the Consolidated Statements of Operations were as follows. Years Ended December 31, (in millions) 2020 2019 2018 Duke Energy $ 415 $ 421 $ 405 Duke Energy Carolinas 43 39 35 Progress Energy 249 256 241 Duke Energy Progress 26 21 19 Duke Energy Florida 223 235 222 Duke Energy Ohio 96 101 105 Duke Energy Indiana 25 23 22 Piedmont 2 2 2
Summary of Effects of New Accounting Pronouncements	Duke Energy recorded an adjustment for the cumulative effect of a change in accounting principle due to the adoption of this standard on January 1, 2020, as shown in the table below: December 31, 2020 Duke Duke Duke Duke Energy Progress Energy Energy (in millions) Energy Carolinas Energy Progress Florida Piedmont Total pretax impact to Retained Earnings $ 120 $ 16 $ 2 $ 1 $ 1 $ 1

Business Segments (Tables)

Business Segments (Tables)	12 Months Ended
	Dec. 31, 2020
Segment Reporting Information [Line Items]
Business Segment Data	Business segment information is presented in the following tables. Segment assets presented exclude intercompany assets. Year Ended December 31, 2020 Electric Gas Total Utilities and Utilities and Commercial Reportable (in millions) Infrastructure Infrastructure Renewables Segments Other Eliminations Total Unaffiliated Revenues $ 21,687 $ 1,653 $ 502 $ 23,842 $ 26 $ — $ 23,868 Intersegment Revenues 33 95 — 128 71 (199) — Total Revenues $ 21,720 $ 1,748 $ 502 $ 23,970 $ 97 $ (199) $ 23,868 Interest Expense $ 1,320 $ 135 $ 66 $ 1,521 $ 657 $ (16) $ 2,162 Depreciation and amortization 4,068 258 199 4,525 209 (29) 4,705 Equity in earnings (losses) of unconsolidated affiliates (1) (2,017) — (2,018) 13 — (2,005) Income tax expense (benefit) 340 (349) (65) (74) (162) — (236) Segment income (loss) (a)(b)(c) 2,669 (1,266) 286 1,689 (426) — 1,263 Less noncontrolling interest 295 Add back preferred stock dividend 107 Income from discontinued operations, net of tax 7 Net income $ 1,082 Capital investments expenditures and acquisitions $ 7,629 $ 1,309 $ 1,219 $ 10,157 $ 264 $ — $ 10,421 Segment assets 138,225 13,849 6,716 158,790 3,598 — 162,388 (a) Electric Utilities and Infrastructure includes $948 million of Impairment charges and a reversal of $152 million included in Regulated electric operating revenue related to the CCR Settlement Agreement filed with the NCUC. Additionally, Electric Utilities and Infrastructure includes $19 million of Impairment charges related to the Clemson University Combined Heat and Power Plant, $5 million of Impairment charges related to the gas pipeline assets and $16 million of shareholder contributions within Operations, maintenance and other related to Duke Energy Carolinas' and Duke Energy Progress' 2019 North Carolina rate cases. See Note 3 for additional information. (b) Gas Utilities and Infrastructure includes $2.1 billion recorded within Equity in (losses) earnings of unconsolidated affiliates and $7 million of Impairment charges related to gas pipeline investments. See Notes 3 and 12 for additional information. (c) Other includes a $98 million reversal of 2018 severance costs due to a partial settlement in the Duke Energy Carolinas' 2019 North Carolina rate case. See Note 3 and 20 for additional information. Year Ended December 31, 2019 Electric Gas Total Utilities and Utilities and Commercial Reportable (in millions) Infrastructure Infrastructure Renewables Segments Other Eliminations Total Unaffiliated Revenues $ 22,798 $ 1,770 $ 487 $ 25,055 $ 24 $ — $ 25,079 Intersegment Revenues 33 96 — 129 71 (200) — Total Revenues $ 22,831 $ 1,866 $ 487 $ 25,184 $ 95 $ (200) $ 25,079 Interest Expense $ 1,345 $ 117 $ 95 $ 1,557 $ 705 $ (58) $ 2,204 Depreciation and amortization 3,951 256 168 4,375 178 (5) 4,548 Equity in earnings (losses) of unconsolidated affiliates 9 114 (4) 119 43 — 162 Income tax expense (benefit) 785 22 (115) 692 (173) — 519 Segment income (loss) (a)(b) 3,536 432 198 4,166 (452) — 3,714 Less noncontrolling interest 177 Add back preferred stock dividend 41 Loss from discontinued operations, net of tax (7) Net income $ 3,571 Capital investments expenditures and acquisitions $ 8,263 $ 1,539 $ 1,423 $ 11,225 $ 221 $ — $ 11,446 Segment assets 135,561 13,921 6,020 155,502 3,148 188 158,838 (a) Electric Utilities and Infrastructure includes a $27 million reduction of a prior year impairment at Citrus County CC related to the plant's cost cap. See Note 3 for additional information. (b) Gas Utilities and Infrastructure includes an after-tax impairment charge of $19 million for the remaining investment in Constitution. See Note 12 for additional information. Year Ended December 31, 2018 Electric Gas Total Utilities and Utilities and Commercial Reportable (in millions) Infrastructure Infrastructure Renewables Segments Other Eliminations Total Unaffiliated Revenues $ 22,242 $ 1,783 $ 477 $ 24,502 $ 19 $ — $ 24,521 Intersegment Revenues 31 98 — 129 70 (199) — Total Revenues $ 22,273 $ 1,881 $ 477 $ 24,631 $ 89 $ (199) $ 24,521 Interest Expense $ 1,288 $ 106 $ 88 $ 1,482 $ 657 $ (45) $ 2,094 Depreciation and amortization 3,523 245 155 3,923 152 (1) 4,074 Equity in earnings (losses) of unconsolidated affiliates 5 27 (1) 31 52 — 83 Income tax expense (benefit) (a) 799 78 (147) 730 (282) — 448 Segment income (loss) (b)(c)(d)(e) 3,058 274 9 3,341 (694) — 2,647 Less noncontrolling interest 22 Income from discontinued operations, net of tax 19 Net income $ 2,644 Capital investments expenditures and acquisitions $ 8,086 $ 1,133 $ 193 $ 9,412 $ 256 $ — $ 9,668 Segment assets 125,364 12,361 4,204 141,929 3,275 188 145,392 (a) All segments include adjustments to the December 31, 2017, estimate of the income tax effects of the Tax Act. Electric Utilities and Infrastructure includes a $24 million expense, Gas Utilities and Infrastructure includes a $1 million expense, Commercial Renewables includes a $3 million benefit and Other includes a $2 million benefit. See Note 23 for additional information. (b) Electric Utilities and Infrastructure includes after-tax regulatory and legislative impairment charges of $202 million related to rate case orders, settlements or other actions of regulators or legislative bodies and an after-tax impairment charge of $46 million related to the Citrus County CC at Duke Energy Florida. See Note 3 for additional information. (c) Gas Utilities and Infrastructure includes an after-tax impairment charge of $42 million for the investment in Constitution. See Note 12 for additional information. (d) Commercial Renewables includes an impairment charge of $91 million, net of $2 million Noncontrolling interests, related to goodwill. See Note 11 for additional information. (e) Other includes $65 million of after-tax costs to achieve the Piedmont merger, $144 million of after-tax severance charges related to a companywide initiative and an $82 million after-tax loss on the sale of Beckjord described below. For additional information, see Note 1 for the Piedmont merger and Note 20 for severance charges.
Schedule of Revenue, By Products and Services	Products and Services The following table summarizes revenues of the reportable segments by type. Retail Wholesale Retail Total (in millions) Electric Electric Natural Gas Other Revenues 2020 Electric Utilities and Infrastructure $ 18,898 $ 1,878 $ — $ 944 $ 21,720 Gas Utilities and Infrastructure — — 1,691 57 1,748 Commercial Renewables — 434 — 68 502 Total Reportable Segments $ 18,898 $ 2,312 $ 1,691 $ 1,069 $ 23,970 2019 Electric Utilities and Infrastructure $ 19,745 $ 2,231 $ — $ 855 $ 22,831 Gas Utilities and Infrastructure — — 1,782 84 1,866 Commercial Renewables — 389 — 98 487 Total Reportable Segments $ 19,745 $ 2,620 $ 1,782 $ 1,037 $ 25,184 2018 Electric Utilities and Infrastructure $ 19,013 $ 2,345 $ — $ 915 $ 22,273 Gas Utilities and Infrastructure — — 1,817 64 1,881 Commercial Renewables — 375 — 102 477 Total Reportable Segments $ 19,013 $ 2,720 $ 1,817 $ 1,081 $ 24,631
Duke Energy Ohio
Segment Reporting Information [Line Items]
Business Segment Data	Year Ended December 31, 2020 Electric Gas Total Utilities and Utilities and Reportable (in millions) Infrastructure Infrastructure Segments Other Eliminations Total Total revenues $ 1,405 $ 453 $ 1,858 $ — $ — $ 1,858 Interest expense $ 85 $ 17 $ 102 $ — $ — $ 102 Depreciation and amortization 200 78 278 — — 278 Income tax expense (benefit) 19 26 45 (2) — 43 Segment income (loss)/Net income 162 96 258 (6) — 252 Capital expenditures $ 548 $ 286 $ 834 $ — $ — $ 834 Segment assets 6,615 3,380 9,995 32 (2) 10,025 Year Ended December 31, 2019 Electric Gas Total Utilities and Utilities and Reportable (in millions) Infrastructure Infrastructure Segments Other Eliminations Total Total revenues $ 1,456 $ 484 $ 1,940 $ — $ — $ 1,940 Interest expense $ 80 $ 29 $ 109 $ — $ — $ 109 Depreciation and amortization 182 83 265 — — 265 Income tax expense (benefit) 20 21 41 (1) — 40 Segment income (loss) 159 85 244 (5) — 239 Loss from discontinued operations, net of tax (1) Net income $ 238 Capital expenditures $ 680 $ 272 $ 952 $ — $ — $ 952 Segment assets 6,188 3,116 9,304 34 — 9,338 Year Ended December 31, 2018 Electric Gas Total Utilities and Utilities and Reportable (in millions) Infrastructure Infrastructure Segments Other Eliminations Total Total revenues $ 1,450 $ 506 $ 1,956 $ 1 $ — $ 1,957 Interest expense $ 67 $ 24 $ 91 $ 1 $ — $ 92 Depreciation and amortization 183 85 268 — — 268 Income tax expense (benefit) 47 24 71 (28) — 43 Segment income (loss)/Net Income (a) 186 93 279 (103) — 176 Capital expenditures $ 655 $ 172 $ 827 $ — $ — $ 827 Segment assets 5,643 2,874 8,517 38 — 8,555 (a) Other includes the loss on the sale of Beckjord, see discussion above.

Regulatory Matters (Tables)

Regulatory Matters (Tables)	12 Months Ended
	Dec. 31, 2020
Public Utilities, General Disclosures [Line Items]
Schedule of Regulatory Assets	The following tables present the regulatory assets and liabilities recorded on the Consolidated Balance Sheets of Duke Energy and Progress Energy. See separate tables below for balances by individual registrant. Duke Energy Progress Energy December 31, December 31, (in millions) 2020 2019 2020 2019 Regulatory Assets AROs – coal ash $ 3,408 $ 4,084 $ 1,357 $ 1,843 AROs – nuclear and other 754 739 685 668 Accrued pension and OPEB 2,317 2,391 875 897 Storm cost deferrals 1,102 1,399 893 1,214 Nuclear asset securitized balance, net 991 1,042 991 1,042 Debt fair value adjustment 950 1,019 — — Retired generation facilities 417 331 363 266 Post-in-service carrying costs (PISCC) and deferred operating expenses 402 329 51 33 Deferred asset – Lee and Harris COLA 356 388 32 38 Hedge costs deferrals 351 356 148 129 Advanced metering infrastructure (AMI) 311 338 102 114 Demand side management (DSM)/Energy Efficiency (EE) 288 343 241 241 Vacation accrual 221 214 42 41 Deferred fuel and purchased power 213 528 162 305 COR settlement 128 133 33 35 NCEMPA deferrals 124 72 124 72 Nuclear deferral 123 107 35 40 Derivatives – natural gas supply contracts 122 117 — — CEP deferral 117 76 — — Amounts due from customers 110 36 — — Qualifying facility contract buyouts 107 121 107 121 Customer connect project 105 65 55 37 Manufactured gas plant (MGP) 104 102 — — ABSAT, coal ash basin closure 98 65 27 15 Deferred pipeline integrity costs 92 79 — — Deferred severance charges 86 — 29 — Incremental COVID-19 expenses 76 — 23 — Other 589 544 158 141 Total regulatory assets 14,062 15,018 6,533 7,292 Less: current portion 1,641 1,796 758 946 Total noncurrent regulatory assets $ 12,421 $ 13,222 $ 5,775 $ 6,346 Regulatory Liabilities Net regulatory liability related to income taxes $ 7,368 $ 7,872 $ 2,411 $ 2,595 Costs of removal 5,883 5,756 2,666 2,561 AROs – nuclear and other 1,512 1,100 — — Provision for rate refunds 344 370 123 123 Accrued pension and OPEB 177 176 — — Amounts to be refunded to customers 51 34 — — Deferred fuel and purchased power 18 1 — 1 Other 1,053 739 491 275 Total regulatory liabilities 16,406 16,048 5,691 5,555 Less: current portion 1,377 784 640 330 Total noncurrent regulatory liabilities $ 15,029 $ 15,264 $ 5,051 $ 5,225
Schedule Of Regulatory Liabilities	The following tables present the regulatory assets and liabilities recorded on the Consolidated Balance Sheets of Duke Energy and Progress Energy. See separate tables below for balances by individual registrant. Duke Energy Progress Energy December 31, December 31, (in millions) 2020 2019 2020 2019 Regulatory Assets AROs – coal ash $ 3,408 $ 4,084 $ 1,357 $ 1,843 AROs – nuclear and other 754 739 685 668 Accrued pension and OPEB 2,317 2,391 875 897 Storm cost deferrals 1,102 1,399 893 1,214 Nuclear asset securitized balance, net 991 1,042 991 1,042 Debt fair value adjustment 950 1,019 — — Retired generation facilities 417 331 363 266 Post-in-service carrying costs (PISCC) and deferred operating expenses 402 329 51 33 Deferred asset – Lee and Harris COLA 356 388 32 38 Hedge costs deferrals 351 356 148 129 Advanced metering infrastructure (AMI) 311 338 102 114 Demand side management (DSM)/Energy Efficiency (EE) 288 343 241 241 Vacation accrual 221 214 42 41 Deferred fuel and purchased power 213 528 162 305 COR settlement 128 133 33 35 NCEMPA deferrals 124 72 124 72 Nuclear deferral 123 107 35 40 Derivatives – natural gas supply contracts 122 117 — — CEP deferral 117 76 — — Amounts due from customers 110 36 — — Qualifying facility contract buyouts 107 121 107 121 Customer connect project 105 65 55 37 Manufactured gas plant (MGP) 104 102 — — ABSAT, coal ash basin closure 98 65 27 15 Deferred pipeline integrity costs 92 79 — — Deferred severance charges 86 — 29 — Incremental COVID-19 expenses 76 — 23 — Other 589 544 158 141 Total regulatory assets 14,062 15,018 6,533 7,292 Less: current portion 1,641 1,796 758 946 Total noncurrent regulatory assets $ 12,421 $ 13,222 $ 5,775 $ 6,346 Regulatory Liabilities Net regulatory liability related to income taxes $ 7,368 $ 7,872 $ 2,411 $ 2,595 Costs of removal 5,883 5,756 2,666 2,561 AROs – nuclear and other 1,512 1,100 — — Provision for rate refunds 344 370 123 123 Accrued pension and OPEB 177 176 — — Amounts to be refunded to customers 51 34 — — Deferred fuel and purchased power 18 1 — 1 Other 1,053 739 491 275 Total regulatory liabilities 16,406 16,048 5,691 5,555 Less: current portion 1,377 784 640 330 Total noncurrent regulatory liabilities $ 15,029 $ 15,264 $ 5,051 $ 5,225
Schedule of Potential Plant Retirements	The table below contains the net carrying value of generating facilities planned for retirement or included in recent IRPs as evaluated for potential retirement. Dollar amounts in the table below are included in Net property, plant and equipment on the Consolidated Balance Sheets as of December 31, 2020, and exclude capitalized asset retirement costs. Remaining Net Capacity Book Value (in MW) (in millions) Duke Energy Carolinas Allen Steam Station Units 1-3 (a) 604 $ 113 Allen Steam Station Units 4-5 (b) 526 338 Cliffside Unit 5 (b) 546 350 Duke Energy Progress Mayo Unit 1 (b) 746 676 Roxboro Units 3-4 (b) 1,409 484 Duke Energy Florida Crystal River Units 4-5 (c) 1,430 1,696 Duke Energy Indiana Gallagher Units 2 and 4 (d) 280 102 Gibson Units 1-5 (e) 2,845 1,866 Cayuga Units 1-2 (e) 1,005 777 Total Duke Energy 9,391 $ 6,402 (a) As part of the 2015 resolution of a lawsuit involving alleged New Source Review violations, Duke Energy Carolinas must retire Allen Steam Station Units 1 through 3 by December 31, 2024. The long-term energy options considered in the IRP could result in retirement of these units earlier than their current estimated useful lives. Unit 3 with a capacity of 270 MW and a net book value of $26 million at December 31, 2020, is expected to be retired in March 2021. (b) These units are included in the IRP filed by Duke Energy Carolinas and Duke Energy Progress in North Carolina and South Carolina on September 1, 2020. The long-term energy options considered in the IRP could result in retirement of these units earlier than their current estimated useful lives. In 2019, Duke Energy Carolinas and Duke Energy Progress filed North Carolina rate cases that included depreciation studies that accelerate end-of-life dates for these plants. A decision by NCUC is expected by the end of the first quarter 2021. (c) On January 14, 2021, Duke Energy Florida filed a settlement agreement with the FPSC, which proposed depreciation rates reflecting retirement dates for Duke Energy Florida's last two coal-fired generating facilities, Crystal River Units 4-5, eight years ahead of schedule in 2034 rather than in 2042, in support of Duke Energy's carbon reduction goals. A request for the FPSC to hold a hearing has been made and a decision by the FPSC is expected in the second quarter 2021. (d) Duke Energy Indiana committed to either retire or stop burning coal at Gallagher Units 2 and 4 by December 31, 2022, as part of the 2016 settlement of Edwardsport IGCC matters. In February 2021, upon approval by MISO of a new retirement date, Duke Energy Indiana determined it would modify the retirement date to June 1, 2021. (e) On July 1, 2019, Duke Energy Indiana filed its 2018 IRP with the IURC. The 2018 IRP included scenarios evaluating the potential retirement of coal-fired generating units at Gibson and Cayuga. The rate case filed July 2, 2019, included proposed depreciation rates reflecting retirement dates from 2026 to 2038. The depreciation rates reflecting these updated retirement dates were approved by the IURC as part of the rate case order issued on June 29, 2020.
Duke Energy Carolinas
Public Utilities, General Disclosures [Line Items]
Schedule of Regulatory Assets	The following tables present the regulatory assets and liabilities recorded on Duke Energy Carolinas' Consolidated Balance Sheets. December 31, Earns/Pays Recovery/Refund (in millions) 2020 2019 a Return Period Ends Regulatory Assets (a) AROs – coal ash $ 1,414 $ 1,696 (h) (b) Accrued pension and OPEB (c) 427 477 Yes (i) Storm cost deferrals 205 178 Yes (b) Retired generation facilities (c) 11 16 Yes 2023 PISCC (c) 32 33 Yes (b) Deferred asset – Lee COLA 324 350 (b) Hedge costs deferrals (c) 174 198 Yes 2041 AMI 154 166 Yes (b) DSM/EE 46 100 (g) (g) Vacation accrual 84 80 2021 Deferred fuel and purchased power 42 222 (e) 2022 COR settlement 95 98 Yes (b) Nuclear deferral 88 67 2022 Customer connect project 50 28 Yes (b) ABSAT, coal ash basin closure 71 50 Yes (b) Deferred severance charges 57 — 2022 Incremental COVID-19 expenses 31 — Yes (b) Other 164 151 (b) Total regulatory assets 3,469 3,910 Less: current portion 473 550 Total noncurrent regulatory assets $ 2,996 $ 3,360 Regulatory Liabilities (a) Net regulatory liability related to income taxes (d) $ 2,874 $ 3,060 (b) Costs of removal (c) 1,975 1,936 Yes (f) AROs – nuclear and other 1,512 1,100 (b) Provision for rate refunds (c) 170 175 Yes Accrued pension and OPEB (c) 32 39 Yes (i) Deferred fuel and purchased power 18 — (e) 2020 Other 427 368 (b) Total regulatory liabilities 7,008 6,678 Less: current portion 473 255 Total noncurrent regulatory liabilities $ 6,535 $ 6,423 (a) Regulatory assets and liabilities are excluded from rate base unless otherwise noted. (b) The expected recovery or refund period varies or has not been determined. (c) Included in rate base. (d) Includes regulatory liabilities related to the change in the federal tax rate as a result of the Tax Act and the change in the North Carolina tax rate, both discussed in Note 23. Portions are included in rate base. (e) Pays interest on over-recovered costs in North Carolina. Includes certain purchased power costs in North Carolina and South Carolina and costs of distributed energy in South Carolina. (f) Recovered over the life of the associated assets. (g) Includes incentives on DSM/EE investments and is recovered through an annual rider mechanism. (h) Earns a debt and equity return on coal ash expenditures for North Carolina and South Carolina retail customers as permitted by various regulatory orders. (i) Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 22 for additional detail.
Schedule Of Regulatory Liabilities	The following tables present the regulatory assets and liabilities recorded on Duke Energy Carolinas' Consolidated Balance Sheets. December 31, Earns/Pays Recovery/Refund (in millions) 2020 2019 a Return Period Ends Regulatory Assets (a) AROs – coal ash $ 1,414 $ 1,696 (h) (b) Accrued pension and OPEB (c) 427 477 Yes (i) Storm cost deferrals 205 178 Yes (b) Retired generation facilities (c) 11 16 Yes 2023 PISCC (c) 32 33 Yes (b) Deferred asset – Lee COLA 324 350 (b) Hedge costs deferrals (c) 174 198 Yes 2041 AMI 154 166 Yes (b) DSM/EE 46 100 (g) (g) Vacation accrual 84 80 2021 Deferred fuel and purchased power 42 222 (e) 2022 COR settlement 95 98 Yes (b) Nuclear deferral 88 67 2022 Customer connect project 50 28 Yes (b) ABSAT, coal ash basin closure 71 50 Yes (b) Deferred severance charges 57 — 2022 Incremental COVID-19 expenses 31 — Yes (b) Other 164 151 (b) Total regulatory assets 3,469 3,910 Less: current portion 473 550 Total noncurrent regulatory assets $ 2,996 $ 3,360 Regulatory Liabilities (a) Net regulatory liability related to income taxes (d) $ 2,874 $ 3,060 (b) Costs of removal (c) 1,975 1,936 Yes (f) AROs – nuclear and other 1,512 1,100 (b) Provision for rate refunds (c) 170 175 Yes Accrued pension and OPEB (c) 32 39 Yes (i) Deferred fuel and purchased power 18 — (e) 2020 Other 427 368 (b) Total regulatory liabilities 7,008 6,678 Less: current portion 473 255 Total noncurrent regulatory liabilities $ 6,535 $ 6,423 (a) Regulatory assets and liabilities are excluded from rate base unless otherwise noted. (b) The expected recovery or refund period varies or has not been determined. (c) Included in rate base. (d) Includes regulatory liabilities related to the change in the federal tax rate as a result of the Tax Act and the change in the North Carolina tax rate, both discussed in Note 23. Portions are included in rate base. (e) Pays interest on over-recovered costs in North Carolina. Includes certain purchased power costs in North Carolina and South Carolina and costs of distributed energy in South Carolina. (f) Recovered over the life of the associated assets. (g) Includes incentives on DSM/EE investments and is recovered through an annual rider mechanism. (h) Earns a debt and equity return on coal ash expenditures for North Carolina and South Carolina retail customers as permitted by various regulatory orders. (i) Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 22 for additional detail.
Duke Energy Progress
Public Utilities, General Disclosures [Line Items]
Schedule of Regulatory Assets	The following tables present the regulatory assets and liabilities recorded on Duke Energy Progress' Consolidated Balance Sheets. December 31, Earns/Pays Recovery/Refund (in millions) 2020 2019 a Return Period Ends Regulatory Assets (a) AROs – coal ash $ 1,347 $ 1,834 (h) (b) AROs – nuclear and other 683 509 (c) Accrued pension and OPEB 393 423 (k) Storm cost deferrals (d) 785 801 Yes (b) Retired generation facilities 189 83 Yes (b) PISCC and deferred operating expenses 51 33 Yes 2054 Deferred asset – Harris COLA 32 38 (b) Hedge costs deferrals 89 85 (b) AMI 57 61 Yes (b) DSM/EE (e) 224 216 (i) (i) Vacation accrual 42 41 2021 Deferred fuel and purchased power 158 266 (f) 2022 COR settlement 33 35 Yes (e) NCEMPA deferrals 124 72 (g) 2042 Nuclear deferral 35 40 2022 Customer connect project 25 17 Yes (b) ABSAT, coal ash basin closure 27 15 Yes (b) Deferred severance charges 29 — 2022 Incremental COVID-19 expenses 23 — Yes (b) Other 122 109 (b) Total regulatory assets 4,468 4,678 Less: current portion 492 526 Total noncurrent regulatory assets $ 3,976 $ 4,152 Regulatory Liabilities (a) Net regulatory liability related to income taxes (l) $ 1,662 $ 1,802 (b) Costs of removal 2,666 2,294 Yes (j) Provision for rate refunds 123 123 Yes Other 473 249 (b) Total regulatory liabilities 4,924 4,468 Less: current portion 530 236 Total noncurrent regulatory liabilities $ 4,394 $ 4,232 (a) Regulatory assets and liabilities are excluded from rate base unless otherwise noted. (b) The expected recovery or refund period varies or has not been determined. (c) Recovery period for costs related to nuclear facilities runs through the decommissioning period of each unit. (d) South Carolina storm costs are included in rate base. (e) Included in rate base. (f) Pays interest on over-recovered costs in North Carolina. Includes certain purchased power costs in North Carolina and South Carolina and costs of distributed energy in South Carolina. (g) South Carolina retail allocated costs are earning a return. (h) Earns a debt and equity return on coal ash expenditures for North Carolina and South Carolina retail customers as permitted by various regulatory orders. (i) Includes incentives on DSM/EE investments and is recovered through an annual rider mechanism. (j) Recovered over the life of the associated assets. (k) Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 22 for additional detail. (l) Includes regulatory liabilities related to the change in the federal tax rate as a result of the Tax Act and the change in the North Carolina tax rate, both discussed in Note 23. Portions are included in rate base.
Schedule Of Regulatory Liabilities	The following tables present the regulatory assets and liabilities recorded on Duke Energy Progress' Consolidated Balance Sheets. December 31, Earns/Pays Recovery/Refund (in millions) 2020 2019 a Return Period Ends Regulatory Assets (a) AROs – coal ash $ 1,347 $ 1,834 (h) (b) AROs – nuclear and other 683 509 (c) Accrued pension and OPEB 393 423 (k) Storm cost deferrals (d) 785 801 Yes (b) Retired generation facilities 189 83 Yes (b) PISCC and deferred operating expenses 51 33 Yes 2054 Deferred asset – Harris COLA 32 38 (b) Hedge costs deferrals 89 85 (b) AMI 57 61 Yes (b) DSM/EE (e) 224 216 (i) (i) Vacation accrual 42 41 2021 Deferred fuel and purchased power 158 266 (f) 2022 COR settlement 33 35 Yes (e) NCEMPA deferrals 124 72 (g) 2042 Nuclear deferral 35 40 2022 Customer connect project 25 17 Yes (b) ABSAT, coal ash basin closure 27 15 Yes (b) Deferred severance charges 29 — 2022 Incremental COVID-19 expenses 23 — Yes (b) Other 122 109 (b) Total regulatory assets 4,468 4,678 Less: current portion 492 526 Total noncurrent regulatory assets $ 3,976 $ 4,152 Regulatory Liabilities (a) Net regulatory liability related to income taxes (l) $ 1,662 $ 1,802 (b) Costs of removal 2,666 2,294 Yes (j) Provision for rate refunds 123 123 Yes Other 473 249 (b) Total regulatory liabilities 4,924 4,468 Less: current portion 530 236 Total noncurrent regulatory liabilities $ 4,394 $ 4,232 (a) Regulatory assets and liabilities are excluded from rate base unless otherwise noted. (b) The expected recovery or refund period varies or has not been determined. (c) Recovery period for costs related to nuclear facilities runs through the decommissioning period of each unit. (d) South Carolina storm costs are included in rate base. (e) Included in rate base. (f) Pays interest on over-recovered costs in North Carolina. Includes certain purchased power costs in North Carolina and South Carolina and costs of distributed energy in South Carolina. (g) South Carolina retail allocated costs are earning a return. (h) Earns a debt and equity return on coal ash expenditures for North Carolina and South Carolina retail customers as permitted by various regulatory orders. (i) Includes incentives on DSM/EE investments and is recovered through an annual rider mechanism. (j) Recovered over the life of the associated assets. (k) Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 22 for additional detail. (l) Includes regulatory liabilities related to the change in the federal tax rate as a result of the Tax Act and the change in the North Carolina tax rate, both discussed in Note 23. Portions are included in rate base.
Duke Energy Florida
Public Utilities, General Disclosures [Line Items]
Schedule of Regulatory Assets	The following tables present the regulatory assets and liabilities recorded on Duke Energy Florida's Consolidated Balance Sheets. December 31, Earns/Pays Recovery/Refund (in millions) 2020 2019 a Return Period Ends Regulatory Assets (a) AROs – coal ash (c) $ 10 $ 9 (b) AROs – nuclear and other (c) 2 159 Yes (b) Accrued pension and OPEB (c) 482 474 Yes (g) Storm cost deferrals (c) 108 413 (e) (b) Nuclear asset securitized balance, net 991 1,042 2036 Retired generation facilities (c) 174 183 Yes (b) Hedge costs deferrals 59 44 Yes 2038 AMI (c) 45 53 Yes 2032 DSM/EE (c) 17 25 Yes 2025 Deferred fuel and purchased power 4 39 (f) 2022 Qualifying facility contract buyouts 107 121 Yes 2034 Customer connect project 30 20 2037 Other 35 31 (d) (b) Total regulatory assets 2,064 2,613 Less: current portion 265 419 Total noncurrent regulatory assets $ 1,799 $ 2,194 Regulatory Liabilities (a) Net regulatory liability related to income taxes (c) $ 749 $ 793 (b) Costs of removal (c) — 267 (d) (b) Deferred fuel and purchased power (c) — 1 (f) Other 19 26 (d) (b) Total regulatory liabilities 768 1,087 Less: current portion 110 94 Total noncurrent regulatory liabilities $ 658 $ 993 (a) Regulatory assets and liabilities are excluded from rate base unless otherwise noted. (b) The expected recovery or refund period varies or has not been determined. (c) Included in rate base. (d) Certain costs earn/pay a return. (e) Earns a debt return/interest once collections begin. (f) Earns commercial paper rate. (g) Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 22 for additional detail.
Schedule Of Regulatory Liabilities	The following tables present the regulatory assets and liabilities recorded on Duke Energy Florida's Consolidated Balance Sheets. December 31, Earns/Pays Recovery/Refund (in millions) 2020 2019 a Return Period Ends Regulatory Assets (a) AROs – coal ash (c) $ 10 $ 9 (b) AROs – nuclear and other (c) 2 159 Yes (b) Accrued pension and OPEB (c) 482 474 Yes (g) Storm cost deferrals (c) 108 413 (e) (b) Nuclear asset securitized balance, net 991 1,042 2036 Retired generation facilities (c) 174 183 Yes (b) Hedge costs deferrals 59 44 Yes 2038 AMI (c) 45 53 Yes 2032 DSM/EE (c) 17 25 Yes 2025 Deferred fuel and purchased power 4 39 (f) 2022 Qualifying facility contract buyouts 107 121 Yes 2034 Customer connect project 30 20 2037 Other 35 31 (d) (b) Total regulatory assets 2,064 2,613 Less: current portion 265 419 Total noncurrent regulatory assets $ 1,799 $ 2,194 Regulatory Liabilities (a) Net regulatory liability related to income taxes (c) $ 749 $ 793 (b) Costs of removal (c) — 267 (d) (b) Deferred fuel and purchased power (c) — 1 (f) Other 19 26 (d) (b) Total regulatory liabilities 768 1,087 Less: current portion 110 94 Total noncurrent regulatory liabilities $ 658 $ 993 (a) Regulatory assets and liabilities are excluded from rate base unless otherwise noted. (b) The expected recovery or refund period varies or has not been determined. (c) Included in rate base. (d) Certain costs earn/pay a return. (e) Earns a debt return/interest once collections begin. (f) Earns commercial paper rate. (g) Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 22 for additional detail.
Duke Energy Ohio
Public Utilities, General Disclosures [Line Items]
Schedule of Regulatory Assets	The following tables present the regulatory assets and liabilities recorded on Duke Energy Ohio's Consolidated Balance Sheets. December 31, Earns/Pays Recovery/Refund (in millions) 2020 2019 a Return Period Ends Regulatory Assets (a) AROs – coal ash $ 22 $ 16 Yes (b) Accrued pension and OPEB 149 155 (g) Storm cost deferrals 4 7 2023 PISCC and deferred operating expenses (c) 16 17 Yes 2083 Hedge costs deferrals 7 6 (b) AMI 36 40 (b) DSM/EE 1 2 (f) (e) Vacation accrual 6 5 2021 Deferred fuel and purchased power — 1 2021 CEP deferral 117 76 Yes (b) MGP 104 102 (b) Deferred pipeline integrity costs 21 17 Yes (b) Other 166 154 (b) Total regulatory assets 649 598 Less: current portion 39 49 Total noncurrent regulatory assets $ 610 $ 549 Regulatory Liabilities (a) Net regulatory liability related to income taxes $ 628 $ 654 (b) Costs of removal 68 86 (d) Provision for rate refunds 45 31 (b) Accrued pension and OPEB 17 16 (g) Other 55 40 (b) Total regulatory liabilities 813 827 Less: current portion 65 64 Total noncurrent regulatory liabilities $ 748 $ 763 (a) Regulatory assets and liabilities are excluded from rate base unless otherwise noted. (b) The expected recovery or refund period varies or has not been determined. (c) Included in rate base. (d) Recovery over the life of the associated assets. (e) Recovered via a rider mechanism. (f) Includes incentives on DSM/EE investments. (g) Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 22 for additional detail.
Schedule Of Regulatory Liabilities	The following tables present the regulatory assets and liabilities recorded on Duke Energy Ohio's Consolidated Balance Sheets. December 31, Earns/Pays Recovery/Refund (in millions) 2020 2019 a Return Period Ends Regulatory Assets (a) AROs – coal ash $ 22 $ 16 Yes (b) Accrued pension and OPEB 149 155 (g) Storm cost deferrals 4 7 2023 PISCC and deferred operating expenses (c) 16 17 Yes 2083 Hedge costs deferrals 7 6 (b) AMI 36 40 (b) DSM/EE 1 2 (f) (e) Vacation accrual 6 5 2021 Deferred fuel and purchased power — 1 2021 CEP deferral 117 76 Yes (b) MGP 104 102 (b) Deferred pipeline integrity costs 21 17 Yes (b) Other 166 154 (b) Total regulatory assets 649 598 Less: current portion 39 49 Total noncurrent regulatory assets $ 610 $ 549 Regulatory Liabilities (a) Net regulatory liability related to income taxes $ 628 $ 654 (b) Costs of removal 68 86 (d) Provision for rate refunds 45 31 (b) Accrued pension and OPEB 17 16 (g) Other 55 40 (b) Total regulatory liabilities 813 827 Less: current portion 65 64 Total noncurrent regulatory liabilities $ 748 $ 763 (a) Regulatory assets and liabilities are excluded from rate base unless otherwise noted. (b) The expected recovery or refund period varies or has not been determined. (c) Included in rate base. (d) Recovery over the life of the associated assets. (e) Recovered via a rider mechanism. (f) Includes incentives on DSM/EE investments. (g) Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 22 for additional detail.
Schedule of MISO Exit Fee Obligations	The following table provides a reconciliation of the beginning and ending balance of Duke Energy Ohio’s recorded liability for its exit obligation and share of MTEP costs recorded in Other within Current Liabilities and Other Noncurrent Liabilities on the Consolidated Balance Sheets. The retail portions of MTEP costs billed by MISO are recovered by Duke Energy Ohio through a non-bypassable rider. As of December 31, 2020, and 2019, $37 million and $40 million, respectively, are recorded in Regulatory assets on Duke Energy Ohio's Consolidated Balance Sheets. Provisions/ Cash (in millions) December 31, 2019 Adjustments Reductions December 31, 2020 Duke Energy Ohio $ 54 $ (1) $ (3) $ 50
Duke Energy Indiana
Public Utilities, General Disclosures [Line Items]
Schedule of Regulatory Assets	The following tables present the regulatory assets and liabilities recorded on Duke Energy Indiana's Consolidated Balance Sheets. December 31, Earns/Pays Recovery/Refund (in millions) 2020 2019 a Return Period Ends Regulatory Assets (a) AROs – coal ash $ 615 $ 529 Yes (b) Accrued pension and OPEB 245 243 (e) Retired generation facilities (c) 43 49 Yes 2030 PISCC and deferred operating expenses (c) 303 246 Yes (b) Hedge costs deferrals 22 23 (b) AMI 19 18 2031 Vacation accrual 12 12 2021 Deferred fuel and purchased power 9 — 2021 Other 60 52 (b) Total regulatory assets 1,328 1,172 Less: current portion 125 90 Total noncurrent regulatory assets $ 1,203 $ 1,082 Regulatory Liabilities (a) Net regulatory liability related to income taxes $ 956 $ 1,008 (b) Costs of removal 599 599 (d) Accrued pension and OPEB 100 90 (e) Amounts to be refunded to customers 17 — (b) Other 66 43 (b) Total regulatory liabilities 1,738 1,740 Less: current portion 111 55 Total noncurrent regulatory liabilities $ 1,627 $ 1,685 (a) Regulatory assets and liabilities are excluded from rate base unless otherwise noted. (b) The expected recovery or refund period varies or has not been determined. (c) Included in rate base. (d) Refunded over the life of the associated assets. (e) Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 22 for additional detail.
Schedule Of Regulatory Liabilities	The following tables present the regulatory assets and liabilities recorded on Duke Energy Indiana's Consolidated Balance Sheets. December 31, Earns/Pays Recovery/Refund (in millions) 2020 2019 a Return Period Ends Regulatory Assets (a) AROs – coal ash $ 615 $ 529 Yes (b) Accrued pension and OPEB 245 243 (e) Retired generation facilities (c) 43 49 Yes 2030 PISCC and deferred operating expenses (c) 303 246 Yes (b) Hedge costs deferrals 22 23 (b) AMI 19 18 2031 Vacation accrual 12 12 2021 Deferred fuel and purchased power 9 — 2021 Other 60 52 (b) Total regulatory assets 1,328 1,172 Less: current portion 125 90 Total noncurrent regulatory assets $ 1,203 $ 1,082 Regulatory Liabilities (a) Net regulatory liability related to income taxes $ 956 $ 1,008 (b) Costs of removal 599 599 (d) Accrued pension and OPEB 100 90 (e) Amounts to be refunded to customers 17 — (b) Other 66 43 (b) Total regulatory liabilities 1,738 1,740 Less: current portion 111 55 Total noncurrent regulatory liabilities $ 1,627 $ 1,685 (a) Regulatory assets and liabilities are excluded from rate base unless otherwise noted. (b) The expected recovery or refund period varies or has not been determined. (c) Included in rate base. (d) Refunded over the life of the associated assets. (e) Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 22 for additional detail.
Piedmont
Public Utilities, General Disclosures [Line Items]
Schedule of Regulatory Assets	The following tables present the regulatory assets and liabilities recorded on Piedmont's Consolidated Balance Sheets. December 31, Earns/Pays Recovery/Refund (in millions) 2020 2019 a Return Period Ends Regulatory Assets (a) AROs – nuclear and other $ 20 $ 16 (d) Accrued pension and OPEB (c) 88 90 (f) Vacation accrual 12 12 2021 Derivatives – natural gas supply contracts (e) 122 117 Amounts due from customers 110 36 Yes (b) Deferred pipeline integrity costs (c) 71 62 2023 Other 32 30 (b) Total regulatory assets 455 363 Less: current portion 153 73 Total noncurrent regulatory assets $ 302 $ 290 Regulatory Liabilities (a) Net regulatory liability related to income taxes $ 499 $ 555 (b) Costs of removal 575 574 (d) Provision for rate refunds 6 41 Yes Accrued pension and OPEB (c) 3 3 (f) Amounts to be refunded to customers 34 34 Yes (b) Other 15 5 (b) Total regulatory liabilities 1,132 1,212 Less: current portion 88 81 Total noncurrent regulatory liabilities $ 1,044 $ 1,131 (a) Regulatory assets and liabilities are excluded from rate base unless otherwise noted. (b) The expected recovery or refund period varies or has not been determined. (c) Included in rate base. (d) Recovery over the life of the associated assets. (e) Balance will fluctuate with changes in the market. Current contracts extend into 2031. (f) Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 22 for additional detail.
Schedule Of Regulatory Liabilities	The following tables present the regulatory assets and liabilities recorded on Piedmont's Consolidated Balance Sheets. December 31, Earns/Pays Recovery/Refund (in millions) 2020 2019 a Return Period Ends Regulatory Assets (a) AROs – nuclear and other $ 20 $ 16 (d) Accrued pension and OPEB (c) 88 90 (f) Vacation accrual 12 12 2021 Derivatives – natural gas supply contracts (e) 122 117 Amounts due from customers 110 36 Yes (b) Deferred pipeline integrity costs (c) 71 62 2023 Other 32 30 (b) Total regulatory assets 455 363 Less: current portion 153 73 Total noncurrent regulatory assets $ 302 $ 290 Regulatory Liabilities (a) Net regulatory liability related to income taxes $ 499 $ 555 (b) Costs of removal 575 574 (d) Provision for rate refunds 6 41 Yes Accrued pension and OPEB (c) 3 3 (f) Amounts to be refunded to customers 34 34 Yes (b) Other 15 5 (b) Total regulatory liabilities 1,132 1,212 Less: current portion 88 81 Total noncurrent regulatory liabilities $ 1,044 $ 1,131 (a) Regulatory assets and liabilities are excluded from rate base unless otherwise noted. (b) The expected recovery or refund period varies or has not been determined. (c) Included in rate base. (d) Recovery over the life of the associated assets. (e) Balance will fluctuate with changes in the market. Current contracts extend into 2031. (f) Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 22 for additional detail.

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Schedule of Legal Reserves	The following tables contain information regarding reserves for probable and estimable costs related to the various environmental sites. These reserves are recorded in Other within Other Noncurrent Liabilities on the Consolidated Balance Sheets. (in millions) December 31, 2020 December 31, 2019 Reserves for Environmental Remediation Duke Energy $ 75 $ 58 Duke Energy Carolinas 19 11 Progress Energy 19 16 Duke Energy Progress 6 4 Duke Energy Florida 12 9 Duke Energy Ohio 22 19 Duke Energy Indiana 6 4 Piedmont 10 8 The table below presents recorded reserves based on management’s best estimate of probable loss for legal matters, excluding asbestos-related reserves. Reserves are classified on the Consolidated Balance Sheets in Other within Other Noncurrent Liabilities and Other within Current Liabilities. The reasonably possible range of loss in excess of recorded reserves is not material, other than as described above. December 31, (in millions) 2020 2019 Reserves for Legal Matters Duke Energy $ 68 $ 62 Duke Energy Carolinas 2 2 Progress Energy 61 55 Duke Energy Progress 13 12 Duke Energy Florida 28 22 Piedmont 1 1
Schedule of Additional Possible Losses in Excess of Recorded Environmental Reserves	Additional losses in excess of recorded reserves that could be incurred for the stages of investigation, remediation and monitoring for environmental sites that have been evaluated at this time are not material except as presented in the table below. (in millions) Duke Energy $ 25 Duke Energy Carolinas 12 Duke Energy Ohio 4 Piedmont 2
Schedule of Purchase Power Obligations	The following table presents executory purchased power contracts with terms exceeding one year, excluding contracts classified as leases. Minimum Purchase Amount at December 31, 2020 Contract (in millions) Expiration 2021 2022 2023 2024 2025 Thereafter Total Duke Energy Progress (a) 2025-2032 $ 66 $ 73 $ 66 $ 67 $ 69 $ 69 $ 410 Duke Energy Florida (b) 2023-2025 335 354 374 262 91 — 1,416 Duke Energy Ohio (c)(d) 2022 130 55 — — — — 185 (a) Contracts represent either 100% of net plant output or vary. (b) Contracts represent 100% of net plant output. (c) Contracts represent between 1% and 11% of net plant output. (d) Excludes PPA with OVEC. See Note 17 for additional information.
Schedule of Natural Gas Supply Contract Commitments	The following table presents future unconditional purchase obligations under natural gas supply and capacity contracts as of December 31, 2020. (in millions) Duke Energy Duke Energy Ohio Piedmont 2021 $ 311 $ 41 $ 270 2022 270 28 242 2023 197 20 177 2024 139 17 122 2025 125 14 111 Thereafter 662 60 602 Total $ 1,704 $ 180 $ 1,524

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Lease Costs and Cash Flows Information	The following tables present the components of lease expense. Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Operating lease expense (a) $ 283 $ 53 $ 162 $ 72 $ 90 $ 11 $ 19 $ 7 Short-term lease expense (a) 4 — 2 1 1 — 1 — Variable lease expense (a) 30 13 13 5 8 — 1 1 Finance lease expense Amortization of leased assets (b) 119 8 24 6 18 — 1 — Interest on lease liabilities (c) 61 30 44 37 7 — — — Total finance lease expense 180 38 68 43 25 — 1 — Total lease expense $ 497 $ 104 $ 245 $ 121 $ 124 $ 11 $ 22 $ 8 (a) Included in Operations, maintenance and other or, for barges and railcars, Fuel used in electric generation and purchased power on the Consolidated Statements of Operations. (b) Included in Depreciation and amortization on the Consolidated Statements of Operations. (c) Included in Interest Expense on the Consolidated Statements of Operations. Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Operating lease expense (a) $ 292 $ 47 $ 161 $ 69 $ 92 $ 11 $ 20 $ 5 Short-term lease expense (a) 16 5 9 4 5 1 2 — Variable lease expense (a) 47 22 22 16 6 — 1 1 Finance lease expense Amortization of leased assets (b) 111 6 21 5 16 1 — — Interest on lease liabilities (c) 61 15 42 33 9 — 1 — Total finance lease expense 172 21 63 38 25 1 1 — Total lease expense $ 527 $ 95 $ 255 $ 127 $ 128 $ 13 $ 24 $ 6 (a) Included in Operations, maintenance and other or, for barges and railcars, Fuel used in electric generation and purchased power on the Consolidated Statements of Operations. (b) Included in Depreciation and amortization on the Consolidated Statements of Operations. (c) Included in Interest Expense on the Consolidated Statements of Operations. Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Cash paid for amounts included in the measurement of lease liabilities (a) Operating cash flows from operating leases $ 271 $ 31 $ 124 $ 52 $ 72 $ 2 $ 6 $ 5 Operating cash flows from finance leases 61 30 44 37 7 — — — Financing cash flows from finance leases 119 8 24 6 18 — 1 — Lease assets obtained in exchange for new lease liabilities (non-cash) Operating (b) $ 116 $ 17 $ — $ — $ — $ — $ 1 $ — Finance 125 125 — — — — — — (a) No amounts were classified as investing cash flows from operating leases for the year ended December 31, 2020. (b) Does not include ROU assets recorded as a result of the adoption of the new lease standard. Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Cash paid for amounts included in the measurement of lease liabilities (a) Operating cash flows from operating leases $ 285 $ 34 $ 131 $ 53 $ 78 $ 2 $ 7 $ 7 Operating cash flows from finance leases 61 15 42 33 9 — 1 — Financing cash flows from finance leases 111 6 21 5 16 1 — — Lease assets obtained in exchange for new lease liabilities (non-cash) Operating (b) $ 194 $ 44 $ 30 $ 30 $ — $ — $ — $ 1 Finance 251 76 175 175 — — — — (a) No amounts were classified as investing cash flows from operating leases for the year ended December 31, 2019.
Schedule of Rent Expense	The following table presents rental expense for operating leases, as reported under the former lease standard. These amounts are included in Operation, maintenance and other and Fuel used in electric generation and purchased power on the Consolidated Statements of Operations. Year Ended (in millions) December 31, 2018 Duke Energy $ 268 Duke Energy Carolinas 49 Progress Energy 143 Duke Energy Progress 75 Duke Energy Florida 68 Duke Energy Ohio 13 Duke Energy Indiana 21 Piedmont 11
Operating Lease Maturities	The following table presents operating lease maturities and a reconciliation of the undiscounted cash flows to operating lease liabilities. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont 2021 $ 229 $ 24 $ 99 $ 44 $ 55 $ 2 $ 5 $ 5 2022 212 22 95 40 55 2 4 5 2023 202 20 95 41 54 2 4 5 2024 186 14 95 41 54 2 4 5 2025 162 10 85 31 54 2 4 5 Thereafter 870 51 376 252 124 20 59 — Total operating lease payments 1,861 141 845 449 396 30 80 25 Less: present value discount (344) (24) (149) (95) (54) (9) (24) (2) Total operating lease liabilities (a) $ 1,517 $ 117 $ 696 $ 354 $ 342 $ 21 $ 56 $ 23 (a) Certain operating lease payments include renewal options that are reasonably certain to be exercised.
Maturities of Finance Lease Liabilities	The following table presents finance lease maturities and a reconciliation of the undiscounted cash flows to finance lease liabilities. December 31, 2020 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Indiana 2021 $ 186 $ 38 $ 68 $ 43 $ 25 $ 1 2022 173 38 68 43 25 1 2023 174 38 68 43 25 1 2024 119 38 52 43 9 1 2025 51 38 48 43 5 1 Thereafter 762 502 481 475 6 26 Total finance lease payments 1,465 692 785 690 95 31 Less: amounts representing interest (620) (398) (408) (394) (14) (21) Total finance lease liabilities $ 845 $ 294 $ 377 $ 296 $ 81 $ 10
Balance Sheet Amounts Recorded for Operating and Finance Leases	The following tables contain additional information related to leases. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Classification Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Assets Operating Operating lease ROU assets, net $ 1,524 $ 110 $ 690 $ 346 $ 344 $ 20 $ 55 $ 20 Finance Net property, plant and equipment 797 312 416 297 119 — 7 — Total lease assets $ 2,321 $ 422 $ 1,106 $ 643 $ 463 $ 20 $ 62 $ 20 Liabilities Current Operating Other current liabilities $ 177 $ 20 $ 73 $ 31 $ 42 $ 1 $ 3 $ 4 Finance Current maturities of long-term debt 129 5 26 7 19 — — — Noncurrent Operating Operating lease liabilities 1,340 97 623 323 300 20 53 19 Finance Long-Term Debt 716 289 351 289 62 — 10 — Total lease liabilities $ 2,362 $ 411 $ 1,073 $ 650 $ 423 $ 21 $ 66 $ 23 December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Classification Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Assets Operating Operating lease ROU assets, net $ 1,658 $ 123 $ 788 $ 387 $ 401 $ 21 $ 57 $ 24 Finance Net property, plant and equipment 926 198 443 308 135 — 7 — Total lease assets $ 2,584 $ 321 $ 1,231 $ 695 $ 536 $ 21 $ 64 $ 24 Liabilities Current Operating Other current liabilities $ 208 $ 27 $ 95 $ 37 $ 58 $ 1 $ 3 $ 4 Finance Current maturities of long-term debt 119 7 24 6 18 — — — Noncurrent Operating Operating lease liabilities 1,432 102 697 354 343 21 55 23 Finance Long-Term Debt 850 172 381 301 80 — 10 — Total lease liabilities $ 2,609 $ 308 $ 1,197 $ 698 $ 499 $ 22 $ 68 $ 27
Supplemental Lease Information	December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Weighted average remaining lease term (years) Operating leases 10 9 10 12 8 17 18 5 Finance leases 13 19 15 17 11 — 25 — Weighted average discount rate (a) Operating leases 3.8 % 3.4 % 3.8 % 3.9 % 3.8 % 4.2 % 4.2 % 3.6 % Finance leases 8.4 % 11.6 % 11.9 % 12.4 % 8.2 % — % 11.9 % — % (a) The discount rate is calculated using the rate implicit in a lease if it is readily determinable. Generally, the rate used by the lessor is not provided to Duke Energy and in these cases the incremental borrowing rate is used. Duke Energy will typically use its fully collateralized incremental borrowing rate as of the commencement date to calculate and record the lease. The incremental borrowing rate is influenced by the lessee’s credit rating and lease term and as such may differ for individual leases, embedded leases or portfolios of leased assets. December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Weighted average remaining lease term (years) Operating leases 11 9 10 12 8 17 18 6 Finance leases 13 19 16 18 11 — 26 — Weighted average discount rate (a) Operating leases 3.9 % 3.5 % 3.8 % 3.9 % 3.8 % 4.2 % 4.1 % 3.6 % Finance leases 8.1 % 11.8 % 11.9 % 12.4 % 8.3 % — % 11.9 % — % (a) The discount rate is calculated using the rate implicit in a lease if it is readily determinable. Generally, the rate used by the lessor is not provided to Duke Energy and in these cases the incremental borrowing rate is used. Duke Energy will typically use its fully collateralized incremental borrowing rate as of the commencement date to calculate and record the lease. The incremental borrowing rate is influenced by the lessee’s credit rating and lease term and as such may differ for individual leases, embedded leases or portfolios of leased assets.

Debt and Credit Facilities (Tab

Debt and Credit Facilities (Tables)	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Schedule of Debt	The following tables summarize outstanding debt. December 31, 2020 Weighted Average Duke Duke Duke Duke Duke Interest Duke Energy Progress Energy Energy Energy Energy (in millions) Rate Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Unsecured debt, maturing 2021-2078 3.71 % $ 23,669 $ 1,150 $ 3,150 $ 700 $ 350 $ 1,180 $ 403 $ 2,800 Secured debt, maturing 2021-2052 2.67 % 4,270 543 1,584 252 1,332 — — — First mortgage bonds, maturing 2021-2050 (a) 4.00 % 29,177 10,008 14,100 7,875 6,225 1,850 3,219 — Finance leases, maturing 2022-2051 (b) 6.96 % 845 294 377 296 81 — 10 — Tax-exempt bonds, maturing 2027-2041 (c) 0.75 % 477 — 48 48 — 77 352 — Notes payable and commercial paper (d) 0.51 % 3,407 — — — — — — — Money pool/intercompany borrowings — 806 3,119 445 196 194 281 530 Fair value hedge carrying value adjustment 4 4 — — — — — — Unamortized debt discount and premium, net (e) 1,217 (20) (31) (19) (11) (29) (18) (5) Unamortized debt issuance costs (f) (330) (62) (113) (44) (62) (14) (25) (15) Total debt 3.62 % $ 62,736 $ 12,723 $ 22,234 $ 9,553 $ 8,111 $ 3,258 $ 4,222 $ 3,310 Short-term notes payable and commercial paper (2,873) — — — — — — — Short-term money pool/intercompany borrowings — (506) (2,969) (295) (196) (169) (131) (530) Current maturities of long-term debt (g) (4,238) (506) (1,426) (603) (823) (50) (70) (160) Total long-term debt (g) $ 55,625 $ 11,711 $ 17,839 $ 8,655 $ 7,092 $ 3,039 $ 4,021 $ 2,620 (a) Substantially all electric utility property is mortgaged under mortgage bond indentures. (b) Duke Energy includes $24 million and $341 million of finance lease purchase accounting adjustments related to Duke Energy Progress and Duke Energy Florida, respectively, related to PPAs that are not accounted for as finance leases in their respective financial statements because of grandfathering provisions in GAAP. (c) Substantially all tax-exempt bonds are secured by first mortgage bonds, letters of credit or the Master Credit Facility. (d) Includes $625 million classified as Long-Term Debt on the Consolidated Balance Sheets due to the existence of long-term credit facilities that backstop these commercial paper balances, along with Duke Energy’s ability and intent to refinance these balances on a long-term basis. The weighted average days to maturity for Duke Energy's commercial paper program was 23 days. (e) Duke Energy includes $1,196 million and $117 million in purchase accounting adjustments related to Progress Energy and Piedmont, respectively. (f) Duke Energy includes $33 million in purchase accounting adjustments primarily related to the merger with Progress Energy. (g) Refer to Note 17 for additional information on amounts from consolidated VIEs. December 31, 2019 Weighted Average Duke Duke Duke Duke Duke Interest Duke Energy Progress Energy Energy Energy Energy (in millions) Rate Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Unsecured debt, maturing 2020-2078 4.02 % $ 22,477 $ 1,150 $ 3,650 $ 700 $ 350 $ 1,110 $ 405 $ 2,399 Secured debt, maturing 2020-2052 3.30 % 4,537 544 1,722 335 1,387 — — — First mortgage bonds, maturing 2020-2049 (a) 4.13 % 27,977 9,557 13,800 7,575 6,225 1,449 3,169 — Finance leases, maturing 2022-2051 (b) 6.60 % 969 179 405 307 98 — 10 — Tax-exempt bonds, maturing 2022-2041 (c) 2.90 % 730 243 48 48 — 77 362 — Notes payable and commercial paper (d) 1.98 % 3,588 — — — — — — — Money pool/intercompany borrowings — 329 1,970 216 — 337 180 476 Fair value hedge carrying value adjustment 5 5 — — — — — — Unamortized debt discount and premium, net (e) 1,294 (23) (29) (17) (11) (30) (19) (2) Unamortized debt issuance costs (f) (316) (55) (111) (40) (62) (12) (20) (13) Total debt 3.92 % $ 61,261 $ 11,929 $ 21,455 $ 9,124 $ 7,987 $ 2,931 $ 4,087 $ 2,860 Short-term notes payable and commercial paper (3,135) — — — — — — — Short-term money pool/intercompany borrowings — (29) (1,821) (66) — (312) (30) (476) Current maturities of long-term debt (g) (3,141) (458) (1,577) (1,006) (571) — (503) — Total long-term debt (g) $ 54,985 $ 11,442 $ 18,057 $ 8,052 $ 7,416 $ 2,619 $ 3,554 $ 2,384 (a) Substantially all electric utility property is mortgaged under mortgage bond indentures. (b) Duke Energy includes $44 million and $419 million of finance lease purchase accounting adjustments related to Duke Energy Progress and Duke Energy Florida, respectively, related to PPAs that are not accounted for as finance leases in their respective financial statements because of grandfathering provisions in GAAP. (c) Substantially all tax-exempt bonds are secured by first mortgage bonds, letters of credit or the Master Credit Facility. (d) Includes $625 million that was classified as Long-Term Debt on the Consolidated Balance Sheets due to the existence of long-term credit facilities that backstop these commercial paper balances, along with Duke Energy’s ability and intent to refinance these balances on a long-term basis. The weighted average days to maturity for Duke Energy's commercial paper programs was 14 days. (e) Duke Energy includes $1,275 million and $137 million in purchase accounting adjustments related to Progress Energy and Piedmont, respectively. (f) Duke Energy includes $37 million in purchase accounting adjustments primarily related to the merger with Progress Energy. (g) Refer to Note 17 for additional information on amounts from consolidated VIEs. The following table shows the significant components of Current maturities of Long-Term Debt on the Consolidated Balance Sheets. The Duke Energy Registrants currently anticipate satisfying these obligations with cash on hand and proceeds from additional borrowings. (in millions) Maturity Date Interest Rate December 31, 2020 Unsecured Debt (a) Duke Energy (Parent) May 2021 0.721 % (b) $ 500 Piedmont June 2021 4.240 % 160 Duke Energy (Parent) September 2021 3.550 % 500 Duke Energy (Parent) September 2021 1.800 % 750 Duke Energy Florida November 2021 0.482 % (b) 200 Secured Debt Duke Energy Florida April 2021 0.972 % (b) 250 First Mortgage Bonds Duke Energy Carolinas June 2021 3.900 % 500 Duke Energy Florida August 2021 3.100 % 300 Duke Energy Progress September 2021 3.000 % 500 Duke Energy Progress September 2021 8.625 % 100 Other (c) 478 Current maturities of long-term debt $ 4,238 (a) During October 2020, Progress Energy early retired $500 million of unsecured debt with an original maturity of January 15, 2021. (b) Debt has a floating interest rate. (c) Includes finance lease obligations, amortizing debt and small bullet maturities. December 31, 2020 Duke Duke Duke Duke Duke Energy Energy Energy Energy (in millions) Energy Carolinas Progress Ohio Indiana Tax-exempt bonds $ 312 $ — $ — $ 27 $ 285 Commercial paper (a) 625 300 150 25 150 Total $ 937 $ 300 $ 150 $ 52 $ 435 December 31, 2019 Duke Duke Duke Duke Duke Energy Energy Energy Energy (in millions) Energy Carolinas Progress Ohio Indiana Tax-exempt bonds $ 312 $ — $ — $ 27 $ 285 Commercial paper (a) 625 300 150 25 150 Total $ 937 $ 300 $ 150 $ 52 $ 435 (a) Progress Energy amounts are equal to Duke Energy Progress amounts.
Schedule of Maturities of Long-term Debt	The following table shows the annual maturities of long-term debt for the next five years and thereafter. Amounts presented exclude short-term notes payable, commercial paper and money pool borrowings and debt issuance costs for the Subsidiary Registrants. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy (a) Carolinas Energy Progress Florida Ohio Indiana Piedmont 2021 $ 4,238 $ 506 $ 1,426 $ 603 $ 823 $ 50 $ 70 $ 160 2022 4,905 721 1,736 1,208 78 — 84 — 2023 3,356 1,008 638 561 77 325 3 45 2024 1,344 9 76 10 66 — 4 40 2025 3,153 310 725 661 64 270 154 205 Thereafter 41,983 9,745 14,802 6,274 6,878 2,486 3,818 2,350 Total long-term debt, including current maturities $ 58,979 $ 12,299 $ 19,403 $ 9,317 $ 7,986 $ 3,131 $ 4,133 $ 2,800 (a) Excludes $1,346 million in purchase accounting adjustments related to the Progress Energy merger and the Piedmont acquisition.
Schedule of Long-term Debt Instruments	The following tables summarize significant debt issuances (in millions). Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Maturity Interest Duke Energy Energy Energy Energy Energy Energy Issuance Date Date Rate Energy (Parent) Carolinas Progress Florida Ohio Indiana Piedmont Unsecured Debt May 2020 (a) Jun 2030 2.450 % $ 500 $ 500 $ — $ — $ — $ — $ — $ — May 2020 (b) Jun 2050 3.350 % 400 — — — — — — 400 August 2020 (c) Feb 2022 0.400 % (d) 700 — — 700 — — — — September 2020 (e) Sep 2025 0.900 % 650 650 — — — — — — September 2020 (e) Jun 2030 2.450 % 350 350 — — — — — — First Mortgage Bonds January 2020 (f) Feb 2030 2.450 % 500 — 500 — — — — — January 2020 (f) Aug 2049 3.200 % 400 — 400 — — — — — March 2020 (g) Apr 2050 2.750 % 550 — — — — — 550 — May 2020 (b) Jun 2030 2.125 % 400 — — — — 400 — — June 2020 (b) Jun 2030 1.750 % 500 — — — 500 — — — August 2020 (h) Aug 2050 2.500 % 600 — — 600 — — — — Total issuances $ 5,550 $ 1,500 $ 900 $ 1,300 $ 500 $ 400 $ 550 $ 400 (a) Debt issued to repay $500 million borrowing made under Duke Energy (Parent) revolving credit facility in March 2020, and for general corporate purposes. (b) Debt issued to repay short-term debt and for general corporate purposes. (c) Debt issued to repay $700 million term loan due December 2020. (d) Debt issuance has a floating interest rate. (e) Debt issued to repay a portion of outstanding commercial paper, to repay a portion of Duke Energy (Parent)'s outstanding $1.7 billion term loan due March 2021 and for general corporate purposes. (f) Debt issued to repay at maturity $450 million first mortgage bonds due June 2020 and for general corporate purposes. (g) Debt issued to repay at maturity $500 million first mortgage bonds due July 2020 and to pay down short-term debt. (h) Debt issued to repay at maturity $300 million first mortgage bonds due September 2020 and for general corporate purposes. Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Maturity Interest Duke Energy Energy Energy Energy Energy Energy Issuance Date Date Rate Energy (Parent) Carolinas Progress Florida Ohio Indiana Piedmont Unsecured Debt March 2019 (a) Mar 2022 2.538 % (b) $ 300 $ 300 $ — $ — $ — $ — $ — $ — March 2019 (a) Mar 2022 3.227 % 300 300 — — — — — — May 2019 (e) Jun 2029 3.500 % 600 — — — — — — 600 June 2019 (a) Jun 2029 3.400 % 600 600 — — — — — — June 2019 (a) Jun 2049 4.200 % 600 600 — — — — — — July 2019 (g) Jul 2049 4.320 % 40 — — — — 40 — — September 2019 (g) Oct 2025 3.230 % 95 — — — — 95 — — September 2019 (g) Oct 2029 3.560 % 75 — — — — 75 — — November 2019 (h) Nov 2021 2.167 % (b) 200 — — — 200 — — — First Mortgage Bonds January 2019 (c) Feb 2029 3.650 % 400 — — — — 400 — — January 2019 (c) Feb 2049 4.300 % 400 — — — — 400 — — March 2019 (d) Mar 2029 3.450 % 600 — — 600 — — — — August 2019 (a) Aug 2029 2.450 % 450 — 450 — — — — — August 2019 (a) Aug 2049 3.200 % 350 — 350 — — — — — September 2019 (f) Oct 2049 3.250 % 500 — — — — — 500 — November 2019 (i) Dec 2029 2.500 % 700 — — — 700 — — — Total issuances $ 6,210 $ 1,800 $ 800 $ 600 $ 900 $ 1,010 $ 500 $ 600 (a) Debt issued to pay down short-term debt and for general corporate purposes. (b) Debt issuance has a floating interest rate. (c) Debt issued to repay at maturity $450 million first mortgage bonds due April 2019, pay down short-term debt and for general corporate purposes. (d) Debt issued to fund eligible green energy projects in the Carolinas. (e) Debt issued to repay in full the outstanding $350 million Piedmont unsecured term loan due September 2019, pay down short-term debt and for general corporate purposes. (f) Debt issued to retire $150 million of pollution control bonds, pay down short-term debt and for general corporate purposes. (g) Debt issued to repay at maturity $100 million debentures due October 2019, pay down short-term debt and for general corporate purposes. (h) Debt issued to fund storm restoration costs and for general corporate purposes. (i) Debt issued to reimburse the payment of existing and new Eligible Green Expenditures in Florida.
Schedule Of Line Of Credit Facilities	The table below includes the current borrowing sublimits and available capacity under these credit facilities. December 31, 2020 Duke Duke Duke Duke Duke Duke Duke Energy Energy Energy Energy Energy Energy (in millions) Energy (Parent) Carolinas Progress Florida Ohio Indiana Piedmont Facility size (a) $ 8,000 $ 2,650 $ 1,475 $ 1,250 $ 800 $ 625 $ 600 $ 600 Reduction to backstop issuances Commercial paper (b) (2,239) — (736) (407) (179) (176) (257) (484) Outstanding letters of credit (40) (34) (4) (2) — — — — Tax-exempt bonds (81) — — — — — (81) — Available capacity $ 5,640 $ 2,616 $ 735 $ 841 $ 621 $ 449 $ 262 $ 116 (a) Represents the sublimit of each borrower. (b) Duke Energy issued $625 million of commercial paper and loaned the proceeds through the money pool to Duke Energy Carolinas, Duke Energy Progress, Duke Energy Ohio and Duke Energy Indiana. The balances are classified as Long-Term Debt Payable to Affiliated Companies in the Consolidated Balance Sheets.

Joint Ownership of Generating_2

Joint Ownership of Generating and Transmission Facilities (Tables)	12 Months Ended
	Dec. 31, 2020
Joint Ownership Of Generating And Transmission Facilities [Abstract]
Schedule Joint Ownership of Generating and Transmission Facilities	The following table presents the Duke Energy Registrants' interest of jointly owned plant or facilities and amounts included on the Consolidated Balance Sheets. All facilities are operated by the Duke Energy Registrants and are included in the Electric Utilities and Infrastructure segment. December 31, 2020 Construction Ownership Property, Plant Accumulated Work in (in millions except for ownership interest) Interest and Equipment Depreciation Progress Duke Energy Carolinas Catawba (units 1 and 2) (a) 19.25 % $ 1,017 $ 518 $ 23 W.S. Lee CC (b) 87.27 % 632 49 1 Duke Energy Indiana Gibson (unit 5) (c) 50.05 % 447 199 4 Vermillion (d) 62.50 % 174 101 1 Transmission and local facilities (c) Various 5,817 1,508 150 (a) Jointly owned with North Carolina Municipal Power Agency Number 1, NCEMC and PMPA. (b) Jointly owned with NCEMC. (c) Jointly owned with WVPA and IMPA. (d) Jointly owned with WVPA.

Asset Retirement Obligations (T

Asset Retirement Obligations (Tables)	12 Months Ended
	Dec. 31, 2020
Asset Retirement Obligation Disclosure [Abstract]
Schedule of Asset Retirement Obligations by Category	The following table presents the AROs recorded on the Consolidated Balance Sheets. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Decommissioning of nuclear power facilities (a) $ 6,845 $ 2,695 $ 4,101 $ 3,642 $ 459 $ — $ — $ — Closure of ash impoundments 5,778 2,597 1,973 1,950 23 67 1,140 — Other 381 58 75 43 32 44 36 20 Total asset retirement obligation $ 13,004 $ 5,350 $ 6,149 $ 5,635 $ 514 $ 111 $ 1,176 $ 20 Less: Current portion 718 264 283 283 — 3 168 — Total noncurrent asset retirement obligation $ 12,286 $ 5,086 $ 5,866 $ 5,352 $ 514 $ 108 $ 1,008 $ 20 (a) Duke Energy amount includes purchase accounting adjustments related to the merger with Progress Energy.
Public Utilities General Disclosures	The following table summarizes information about the most recent site-specific nuclear decommissioning cost studies. Decommissioning costs are stated in 2018 or 2019 dollars, depending on the year of the cost study, and include costs to decommission plant components not subject to radioactive contamination. Annual Funding Decommissioning (in millions) Requirement (a) Costs (a) Year of Cost Study Duke Energy $ 27 $ 9,105 2018 or 2019 Duke Energy Carolinas (b)(c) — 4,365 2018 Duke Energy Progress (d) 27 4,181 2019 Duke Energy Florida (e) — 559 N/A (a) Amounts for Progress Energy equal the sum of Duke Energy Progress and Duke Energy Florida. (b) Decommissioning cost for Duke Energy Carolinas reflects its ownership interest in jointly owned reactors. Other joint owners are responsible for decommissioning costs related to their interest in the reactors. (c) Duke Energy Carolinas' site-specific nuclear decommissioning cost study completed in 2018 was filed with the NCUC and PSCSC in 2019. A new funding study was also completed and filed with the NCUC and PSCSC in 2019. (d) Duke Energy Progress' site-specific nuclear decommissioning cost study completed in 2019 was filed with the NCUC and PSCSC in March 2020. Duke Energy Progress also completed a funding study, which was filed with the NCUC and PSCSC in July 2020. (e) During 2019, Duke Energy Florida reached an agreement to transfer decommissioning work for Crystal River Unit 3 to a third party and decommissioning costs are based on the agreement with this third party rather than a cost study. Regulatory approval was received from the NRC and the FPSC in April 2020 and August 2020, respectively. See Note 3 for more information. The following table presents the fair value of NDTF assets legally restricted for purposes of settling AROs associated with nuclear decommissioning. Duke Energy Florida entered into an agreement with a third party to decommission Crystal River Unit 3 and was granted an exemption from the NRC, which allows for use of the NDTF for all aspects of nuclear decommissioning. The entire balance of Duke Energy Florida's NDTF may be applied toward license termination, spent fuel and site restoration costs incurred to decommission Crystal River Unit 3 and is excluded from the table below. See Note 16 for additional information related to the fair value of the Duke Energy Registrants' NDTFs. December 31, (in millions) 2020 2019 Duke Energy $ 7,726 $ 6,766 Duke Energy Carolinas 4,381 3,837 Duke Energy Progress 3,345 2,929 Unit Year of Expiration Duke Energy Carolinas Catawba Units 1 and 2 2043 McGuire Unit 1 2041 McGuire Unit 2 2043 Oconee Units 1 and 2 2033 Oconee Unit 3 2034 Duke Energy Progress Brunswick Unit 1 2036 Brunswick Unit 2 2034 Harris 2046 Robinson 2030
Rollforward Schedule of Asset Retirement Obligations	The following tables present changes in the liability associated with AROs. Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Balance at December 31, 2018 $ 10,467 $ 3,949 $ 5,411 $ 4,820 $ 591 $ 93 $ 722 $ 19 Accretion expense (a) 508 235 252 227 25 3 28 1 Liabilities settled (b) (895) (329) (499) (460) (39) (12) (54) — Liabilities incurred in the current year 25 18 7 — 7 — — — Revisions in estimates of cash flows (c) 3,213 1,861 1,300 1,306 (6) (4) 136 (3) Balance at December 31, 2019 13,318 5,734 6,471 5,893 578 80 832 17 Accretion expense (a) 542 258 246 225 21 4 33 1 Liabilities settled (b) (724) (198) (451) (358) (93) (2) (74) — Liabilities incurred in the current year 22 — 5 — 5 — — — Revisions in estimates of cash flows (d) (154) (444) (122) (125) 3 29 385 2 Balance at December 31, 2020 $ 13,004 $ 5,350 $ 6,149 $ 5,635 $ 514 $ 111 $ 1,176 $ 20 (a) Substantially all accretion expense for the years ended December 31, 2020, and 2019, relates to Duke Energy’s regulated operations and has been deferred in accordance with regulatory accounting treatment. (b) Amounts primarily relate to ash impoundment closures and nuclear decommissioning. (c) Amounts primarily relate to increases in closure estimates for certain ash impoundments as a result of the NCDEQ's April 1, 2019, Order and the related settlement agreement dated December 31, 2019. (d) Primarily relates to decreases due to revised basin closure cost estimates, partially offset by increases related to new closure plan approvals, post closure maintenance and beneficiation costs. Duke Energy Indiana estimates also include the impacts of closure estimates for certain ash impoundments due to the impact of Hoosier Environmental Council’s petition filed with the court challenging the Indiana Department of Environmental Management’s partial approval of Duke Energy Indiana’s ash pond closure plan. See Note 4 for more information on Hoosier Environmental Council's petition. The incremental amount recorded represents the discounted cash flows for estimated closure costs based upon the probability weightings of the potential closure methods as evaluated on a site-by-site basis.

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant and Equipment	The composite weighted average depreciation rates, excluding nuclear fuel, are included in the table that follows. Years Ended December 31, 2020 2019 2018 Duke Energy 3.0 % 3.1 % 3.0 % Duke Energy Carolinas 2.8 % 2.8 % 2.8 % Progress Energy 3.2 % 3.1 % 2.9 % Duke Energy Progress 3.1 % 3.1 % 2.9 % Duke Energy Florida 3.3 % 3.1 % 3.0 % Duke Energy Ohio 2.9 % 2.6 % 2.8 % Duke Energy Indiana 3.5 % 3.3 % 3.3 % Piedmont 2.3 % 2.4 % 2.5 % The following tables summarize the property, plant and equipment for Duke Energy and its subsidiary registrants. December 31, 2020 Average Remaining Duke Duke Duke Duke Duke Useful Life Duke Energy Progress Energy Energy Energy Energy (in millions) (Years) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Land $ 2,046 $ 536 $ 908 $ 463 $ 445 $ 171 $ 118 $ 279 Plant – Regulated Electric generation, distribution and transmission 39 117,107 44,059 50,785 31,375 19,410 6,255 16,008 — Natural gas transmission and distribution 54 10,799 — — — — 3,136 — 7,663 Other buildings and improvements 36 2,038 740 459 197 262 374 300 165 Plant – Nonregulated Electric generation, distribution and transmission 27 5,444 — — — — — — — Other buildings and improvements 10 519 — — — — — — — Nuclear fuel 3,284 1,837 1,447 1,447 — — — — Equipment 15 2,608 620 759 498 261 385 238 122 Construction in process 6,645 1,645 2,013 709 1,304 407 409 581 Other 14 5,090 1,203 1,521 1,070 441 294 309 324 Total property, plant and equipment (a)(e) 155,580 50,640 57,892 35,759 22,123 11,022 17,382 9,134 Total accumulated depreciation – regulated (b)(c) (46,216) (17,453) (18,368) (12,801) (5,560) (3,013) (5,661) (1,749) Total accumulated depreciation – nonregulated (d)(e) (2,611) — — — — — — — Generation facilities to be retired, net 29 — 29 29 — — — — Total net property, plant and equipment $ 106,782 $ 33,187 $ 39,553 $ 22,987 $ 16,563 $ 8,009 $ 11,721 $ 7,385 (a) Includes finance leases of $832 million, $335 million, $416 million, $297 million, $119 million and $10 million at Duke Energy, Duke Energy Carolinas, Progress Energy, Duke Energy Progress, Duke Energy Florida and Duke Energy Indiana, respectively, primarily within Plant – Regulated. The Progress Energy, Duke Energy Progress and Duke Energy Florida amounts are net of $141 million, $24 million and $117 million, respectively, of accumulated amortization of finance leases. (b) Includes $1,832 million, $1,010 million, $822 million and $822 million of accumulated amortization of nuclear fuel at Duke Energy, Duke Energy Carolinas, Progress Energy and Duke Energy Progress, respectively. (c) Includes accumulated amortization of finance leases of $12 million, $23 million and $3 million at Duke Energy, Duke Energy Carolinas and Duke Energy Indiana, respectively. (d) Includes accumulated amortization of finance leases of $23 million at Duke Energy. (e) Includes gross property, plant and equipment cost of consolidated VIEs of $6,394 million and accumulated depreciation of consolidated VIEs of $1,242 million at Duke Energy. December 31, 2019 Average Remaining Duke Duke Duke Duke Duke Useful Life Duke Energy Progress Energy Energy Energy Energy (in millions) (Years) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Land $ 2,091 $ 520 $ 884 $ 449 $ 435 $ 150 $ 117 $ 388 Plant – Regulated Electric generation, distribution and transmission 39 111,739 42,723 48,142 30,018 18,124 5,838 15,032 — Natural gas transmission and distribution 54 9,839 — — — — 2,892 — 6,947 Other buildings and improvements 32 1,810 714 401 162 239 269 278 148 Plant – Nonregulated Electric generation, distribution and transmission 28 5,103 — — — — — — — Other buildings and improvements 9 488 — — — — — — — Nuclear fuel 3,253 1,891 1,362 1,362 — — — — Equipment 13 2,313 546 665 452 213 319 205 128 Construction in process 6,102 1,389 2,149 1,114 1,035 504 381 531 Other 13 4,916 1,139 1,467 1,046 411 269 292 304 Total property, plant and equipment (a)(e) 147,654 48,922 55,070 34,603 20,457 10,241 16,305 8,446 Total accumulated depreciation – regulated (b)(c) (43,419) (16,525) (17,159) (11,915) (5,236) (2,843) (5,233) (1,681) Total accumulated depreciation – nonregulated (d)(e) (2,354) — — — — — — — Generation facilities to be retired, net 246 — 246 246 — — — — Total net property, plant and equipment $ 102,127 $ 32,397 $ 38,157 $ 22,934 $ 15,221 $ 7,398 $ 11,072 $ 6,765 (a) Includes finance leases of $952 million, $211 million, $443 million, $308 million, $135 million, and $10 million at Duke Energy, Duke Energy Carolinas, Progress Energy, Duke Energy Progress, Duke Energy Florida and Duke Energy Indiana, respectively, primarily within Plant – Regulated. The Progress Energy, Duke Energy Progress and Duke Energy Florida amounts are net of $143 million, $17 million and $126 million, respectively, of accumulated amortization of finance leases. (b) Includes $1,807 million, $1,082 million, $725 million and $725 million of accumulated amortization of nuclear fuel at Duke Energy, Duke Energy Carolinas, Progress Energy and Duke Energy Progress, respectively. (c) Includes accumulated amortization of finance leases of $6 million, $13 million, and $3 million at Duke Energy, Duke Energy Carolinas and Duke Energy Indiana, respectively. (d) Includes accumulated amortization of finance leases of $20 million at Duke Energy. (e) Includes gross property, plant and equipment cost of consolidated VIEs of $5,747 million and accumulated depreciation of consolidated VIEs of $1,041 million at Duke Energy.
Schedule Of Capitalized Interest	The following tables present capitalized interest, which includes the debt component of AFUDC. Years Ended December 31, (in millions) 2020 2019 2018 Duke Energy $ 112 $ 159 $ 161 Duke Energy Carolinas 28 30 35 Progress Energy 17 31 51 Duke Energy Progress 12 28 26 Duke Energy Florida 5 3 25 Duke Energy Ohio 26 22 17 Duke Energy Indiana 10 26 27 Piedmont 8 26 17

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill By Reportable Operating Segment	The following table presents goodwill by reportable segment for Duke Energy included on Duke Energy's Consolidated Balance Sheets at December 31, 2020, and 2019. Electric Utilities Gas Utilities Commercial (in millions) and Infrastructure and Infrastructure Renewables Total Goodwill Balance at December 31, 2019 $ 17,379 $ 1,924 $ 122 $ 19,425 Accumulated impairment charges — — (122) (122) Goodwill balance at December 31, 2019, adjusted for accumulated impairment charges $ 17,379 $ 1,924 $ — $ 19,303 Goodwill Balance at December 31, 2020 $ 17,379 $ 1,924 $ 122 $ 19,425 Accumulated impairment charges — — (122) (122) Goodwill balance at December 31, 2020, adjusted for accumulated impairment charges $ 17,379 $ 1,924 $ — $ 19,303
Schedule of Intangible Assets	The following tables show the carrying amount and accumulated amortization of intangible assets included in Other within Other Noncurrent Assets on the Consolidated Balance Sheets of the Duke Energy Registrants at December 31, 2020, and 2019. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Emission allowances $ 8 $ — $ 5 $ 2 $ 3 $ — $ 2 $ — Renewable energy certificates 196 65 130 130 — 1 — — Natural gas, coal and power contracts 24 — — — — — 24 — Renewable operating and development projects 107 — — — — — — — Other 20 — — — — — — — Total gross carrying amounts 355 65 135 132 3 1 26 — Accumulated amortization – natural gas, coal and power contracts (23) — — — — — (23) — Accumulated amortization – renewable operating and development projects (34) — — — — — — — Accumulated amortization – other (3) — — — — — — — Total accumulated amortization (60) — — — — — (23) — Total intangible assets, net $ 295 $ 65 $ 135 $ 132 $ 3 $ 1 $ 3 $ — December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Emission allowances $ 18 $ — $ 5 $ 2 $ 3 $ — $ 12 $ — Renewable energy certificates 172 53 118 118 — 1 — — Natural gas, coal and power contracts 24 — — — — — 24 — Renewable operating and development projects 89 — — — — — — — Other 2 — — — — — — — Total gross carrying amounts 305 53 123 120 3 1 36 — Accumulated amortization – natural gas, coal and power contracts (21) — — — — — (21) — Accumulated amortization – renewable operating and development projects (34) — — — — — — — Accumulated amortization – other (1) — — — — — — — Total accumulated amortization (56) — — — — — (21) — Total intangible assets, net $ 249 $ 53 $ 123 $ 120 $ 3 $ 1 $ 15 $ —

Investments in Unconsolidated_2

Investments in Unconsolidated Affiliates (Tables)	12 Months Ended
	Dec. 31, 2020
Equity Method Investments and Joint Ventures [Abstract]
Investments in Equity Method Unconsolidated Affiliates	The following table presents Duke Energy’s investments in unconsolidated affiliates accounted for under the equity method, as well as the respective equity in earnings, by segment. Years Ended December 31, 2020 2019 2018 Equity in Equity in Equity in (in millions) Investments earnings Investments earnings Investments earnings Electric Utilities and Infrastructure $ 105 $ (1) $ 122 $ 9 $ 97 $ 6 Gas Utilities and Infrastructure 215 (2,017) 1,388 114 1,003 27 Commercial Renewables 534 — 314 (4) 201 (1) Other 107 13 112 43 108 51 Total $ 961 $ (2,005) $ 1,936 $ 162 $ 1,409 $ 83 The table below outlines Duke Energy's ownership interests in natural gas pipeline companies and natural gas storage facilities. Investment Amount (in millions) Ownership December 31, Entity Name Interest 2020 2019 Pipeline Investments (a) ACP (b) 47 % $ — $ 1,179 Sabal Trail 7.5 % 120 121 Cardinal (c) 21.49 % 9 9 Storage Facilities Pine Needle (c) 45 % 27 28 Hardy Storage (c) 50 % 56 51 Other 29.68 % 3 — Total Investments (d) $ 215 $ 1,388 (a) Duke Energy recorded OTTIs of $25 million and $55 million within Equity in (losses) earnings of unconsolidated affiliates on Duke Energy's Consolidated Statements of Operations for the years ended December 31, 2019, and 2018, respectively, to completely impair its 24% ownership interest in Constitution. (b) In 2020, Duke Energy determined it would no longer continue its investment in the construction of the ACP pipeline. See Notes 3 and 7 for further information. (c) Piedmont owns the Cardinal, Pine Needle and Hardy Storage investments. (d) Duke Energy includes purchase accounting adjustments related to Piedmont. For the year ended December 31, 2020, Duke Energy's investment in ACP met the requirements of S-X Rule 4-08(g) to provide summarized financial information. The following table provides summary information for ACP as required under S-X Rule 1-02(bb) for the comparative periods in Duke Energy's consolidated balance sheets and consolidated statements of operations. December 31, (in millions) 2020 2019 Current assets $ 43 $ 17 Noncurrent assets 93 4,091 Current liabilities 1,965 37 Noncurrent liabilities 167 1,760 Membership interests (1,996) 2,311 Years Ended December 31, 2020 2019 2018 Net revenues $ — $ — $ — Operating loss (4,612) (5) (6) Net (loss) income (4,512) 246 138 Net (loss) income attributable to Duke Energy $ (2,121) $ 116 $ 65

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2020
Related Party Transactions [Abstract]
Related Party Transactions, Other Revenue and Expense	Material amounts related to transactions with related parties included in the Consolidated Statements of Operations and Comprehensive Income are presented in the following table. Years Ended December 31, (in millions) 2020 2019 2018 Duke Energy Carolinas Corporate governance and shared service expenses (a) $ 753 $ 841 $ 985 Indemnification coverages (b) 20 20 22 Joint Dispatch Agreement (JDA) revenue (c) 25 60 84 JDA expense (c) 114 186 207 Intercompany natural gas purchases (d) 15 15 15 Progress Energy Corporate governance and shared service expenses (a) $ 715 $ 778 $ 906 Indemnification coverages (b) 36 37 34 JDA revenue (c) 114 186 207 JDA expense (c) 25 60 84 Intercompany natural gas purchases (d) 75 76 78 Duke Energy Progress Corporate governance and shared service expenses (a) $ 420 $ 462 $ 577 Indemnification coverages (b) 17 15 13 JDA revenue (c) 114 186 207 JDA expense (c) 25 60 84 Intercompany natural gas purchases (d) 75 76 78 Duke Energy Florida Corporate governance and shared service expenses (a) $ 295 $ 316 $ 329 Indemnification coverages (b) 19 22 21 Duke Energy Ohio Corporate governance and shared service expenses (a) $ 326 $ 354 $ 374 Indemnification coverages (b) 4 4 5 Duke Energy Indiana Corporate governance and shared service expenses (a) $ 401 $ 412 $ 405 Indemnification coverages (b) 8 7 7 Piedmont Corporate governance and shared service expenses (a) $ 140 $ 138 $ 170 Indemnification coverages (b) 3 3 2 Intercompany natural gas sales (d) 90 91 93 Natural gas storage and transportation costs (e) 23 23 25 (a) The Subsidiary Registrants are charged their proportionate share of corporate governance and other shared services costs, primarily related to human resources, employee benefits, information technology, legal and accounting fees, as well as other third-party costs. These amounts are primarily recorded in Operation, maintenance and other on the Consolidated Statements of Operations and Comprehensive Income. (b) The Subsidiary Registrants incur expenses related to certain indemnification coverages through Bison, Duke Energy’s wholly owned captive insurance subsidiary. These expenses are recorded in Operation, maintenance and other on the Consolidated Statements of Operations and Comprehensive Income. (c) Duke Energy Carolinas and Duke Energy Progress participate in a JDA, which allows the collective dispatch of power plants between the service territories to reduce customer rates. Revenues from the sale of power and expenses from the purchase of power pursuant to the JDA are recorded in Operating Revenues and Fuel used in electric generation and purchased power, respectively, on the Consolidated Statements of Operations and Comprehensive Income. (d) Piedmont provides long-term natural gas delivery service to certain Duke Energy Carolinas and Duke Energy Progress natural gas-fired generation facilities. Piedmont records the sales in Operating Revenues, and Duke Energy Carolinas and Duke Energy Progress record the related purchases as a component of Fuel used in electric generation and purchased power on their respective Consolidated Statements of Operations and Comprehensive Income. These intercompany revenues and expenses are eliminated in consolidation. (e) Piedmont has related party transactions as a customer of its equity method investments in Pine Needle, Hardy Storage, and Cardinal natural gas storage and transportation facilities. These expenses are included in Cost of natural gas on Piedmont's Consolidated Statements of Operations and Comprehensive Income. Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Carolinas Energy Progress Florida Ohio Indiana Piedmont December 31, 2020 Intercompany income tax receivable $ — $ — $ — $ — $ — $ 9 $ 10 Intercompany income tax payable 31 33 46 35 2 — — December 31, 2019 Intercompany income tax receivable $ — $ 125 $ 28 $ — $ 9 $ 28 $ 13 Intercompany income tax payable 5 — — 2 — — —

Derivatives and Hedging (Tables

Derivatives and Hedging (Tables)	12 Months Ended
	Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Notional Amounts of Outstanding Derivative Positions	The following tables show notional amounts of outstanding derivatives related to interest rate risk. December 31, 2020 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Cash flow hedges $ 632 $ — $ — $ — $ — $ — Undesignated contracts 1,177 400 750 750 — 27 Total notional amount (a) $ 1,809 $ 400 $ 750 $ 750 $ — $ 27 December 31, 2019 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Cash flow hedges $ 993 $ — $ — $ — $ — $ — Undesignated contracts 1,277 450 800 250 550 27 Total notional amount (a) $ 2,270 $ 450 $ 800 $ 250 $ 550 $ 27 (a) Duke Energy includes amounts related to consolidated VIEs of $632 million in cash flow hedges as of December 31, 2020, and $693 million in cash flow hedges as of December 31, 2019. The tables below include volumes of outstanding commodity derivatives. Amounts disclosed represent the absolute value of notional volumes of commodity contracts excluding NPNS. The Duke Energy Registrants have netted contractual amounts where offsetting purchase and sale contracts exist with identical delivery locations and times of delivery. Where all commodity positions are perfectly offset, no quantities are shown. December 31, 2020 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy Carolinas Energy Progress Ohio Indiana Piedmont Electricity (GWh) (a) 35,409 — — — 2,559 10,802 — Natural gas (millions of Dth) 678 145 158 158 — 2 373 December 31, 2019 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy Carolinas Energy Progress Ohio Indiana Piedmont Electricity (GWh) 15,858 — — — 1,887 13,971 — Natural gas (millions of Dth) 704 130 160 160 — 3 411 (a) Duke Energy includes 22,048 GWh that relates to cash flow hedges.
Location and Fair Value of Derivatives Recognized in the Consolidated Balance Sheets	The following tables show the fair value and balance sheet location of derivative instruments. Although derivatives subject to master netting arrangements are netted on the Consolidated Balance Sheets, the fair values presented below are shown gross and cash collateral on the derivatives has not been netted against the fair values shown. Derivative Assets December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Commodity Contracts Not Designated as Hedging Instruments Current $ 30 $ 14 $ 9 $ 9 $ — $ 1 $ 6 $ 1 Noncurrent 13 6 6 6 — — — — Total Derivative Assets – Commodity Contracts $ 43 $ 20 $ 15 $ 15 $ — $ 1 $ 6 $ 1 Interest Rate Contracts Not Designated as Hedging Instruments Current $ 18 $ — $ 18 $ 18 $ — $ — $ — $ — Total Derivative Assets – Interest Rate Contracts $ 18 $ — $ 18 $ 18 $ — $ — $ — $ — Total Derivative Assets $ 61 $ 20 $ 33 $ 33 $ — $ 1 $ 6 $ 1 Derivative Liabilities December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Commodity Contracts Designated as Hedging Instruments Current $ 14 $ — $ — $ — $ — $ — $ — $ — Noncurrent 70 — — — — — — — Not Designated as Hedging Instruments Current $ 30 $ 13 $ 2 $ 2 $ — $ — $ 1 $ 15 Noncurrent 137 3 27 12 — — — 107 Total Derivative Liabilities – Commodity Contracts $ 251 $ 16 $ 29 $ 14 $ — $ — $ 1 $ 122 Interest Rate Contracts Designated as Hedging Instruments Current $ 15 $ — $ — $ — $ — $ — $ — $ — Noncurrent 48 — — — — — — — Not Designated as Hedging Instruments Current 5 4 — — — 1 — — Noncurrent 5 — — — — 5 — — Total Derivative Liabilities – Interest Rate Contracts $ 73 $ 4 $ — $ — $ — $ 6 $ — $ — Total Derivative Liabilities $ 324 $ 20 $ 29 $ 14 $ — $ 6 $ 1 $ 122 Derivative Assets December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Commodity Contracts Not Designated as Hedging Instruments Current $ 17 $ — $ — $ — $ — $ 3 $ 13 $ 1 Noncurrent 1 — — — — 1 — — Total Derivative Assets – Commodity Contracts $ 18 $ — $ — $ — $ — $ 4 $ 13 $ 1 Interest Rate Contracts Not Designated as Hedging Instruments Current 6 — 6 — 6 — — — Total Derivative Assets – Interest Rate Contracts $ 6 $ — $ 6 $ — $ 6 $ — $ — $ — Equity Securities Contracts Not Designated as Hedging Instruments Current $ 1 $ — $ 1 $ — $ 1 $ — $ — $ — Total Derivative Assets – Equity Securities Contracts $ 1 $ — $ 1 $ — $ 1 $ — $ — $ — Total Derivative Assets $ 25 $ — $ 7 $ — $ 7 $ 4 $ 13 $ 1 Derivative Liabilities December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Commodity Contracts Not Designated as Hedging Instruments Current $ 67 $ 33 $ 26 $ 26 $ — $ — $ 1 $ 7 Noncurrent 156 10 37 22 — — — 110 Total Derivative Liabilities – Commodity Contracts $ 223 $ 43 $ 63 $ 48 $ — $ — $ 1 $ 117 Interest Rate Contracts Designated as Hedging Instruments Current $ 19 $ — $ — $ — $ — $ — $ — $ — Noncurrent 21 — — — — — — — Not Designated as Hedging Instruments Current 8 6 1 1 — 1 — — Noncurrent 5 — — — — 5 — — Total Derivative Liabilities – Interest Rate Contracts $ 53 $ 6 $ 1 $ 1 $ — $ 6 $ — $ — Equity Securities Contracts Not Designated as Hedging Instruments Current $ 24 $ — $ 24 $ — $ 24 $ — $ — $ — Total Derivative Liabilities – Equity Securities Contracts $ 24 $ — $ 24 $ — $ 24 $ — $ — $ — Total Derivative Liabilities $ 300 $ 49 $ 88 $ 49 $ 24 $ 6 $ 1 $ 117
Offsetting Assets	The following tables present the line items on the Consolidated Balance Sheets where derivatives are reported. Substantially all of Duke Energy's outstanding derivative contracts are subject to enforceable master netting arrangements. The gross amounts offset in the tables below show the effect of these netting arrangements on financial position and include collateral posted to offset the net position. The amounts shown are calculated by counterparty. Accounts receivable or accounts payable may also be available to offset exposures in the event of bankruptcy. These amounts are not included in the tables below. Derivative Assets December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Current Gross amounts recognized $ 48 $ 14 $ 27 $ 27 $ — $ 1 $ 6 $ 1 Gross amounts offset (3) (2) (2) (2) — — — — Net amounts presented in Current Assets: Other $ 45 $ 12 $ 25 $ 25 $ — $ 1 $ 6 $ 1 Noncurrent Gross amounts recognized $ 13 $ 6 $ 6 $ 6 $ — $ — $ — $ — Gross amounts offset (5) (1) (4) (4) — — — — Net amounts presented in Other Noncurrent Assets: Other $ 8 $ 5 $ 2 $ 2 $ — $ — $ — $ — Derivative Assets December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Current Gross amounts recognized $ 24 $ — $ 7 $ — $ 7 $ 3 $ 13 $ 1 Gross amounts offset (1) — (1) — (1) — — — Net amounts presented in Current Assets: Other $ 23 $ — $ 6 $ — $ 6 $ 3 $ 13 $ 1 Noncurrent Gross amounts recognized $ 1 $ — $ — $ — $ — $ 1 $ — $ — Gross amounts offset — — — — — — — — Net amounts presented in Other Noncurrent Assets: Other $ 1 $ — $ — $ — $ — $ 1 $ — $ —
Offsetting Liabilities	Derivative Liabilities December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Current Gross amounts recognized $ 64 $ 17 $ 2 $ 2 $ — $ 1 $ 1 $ 15 Gross amounts offset (3) (2) (2) (2) — — — — Net amounts presented in Current Liabilities: Other $ 61 $ 15 $ — $ — $ — $ 1 $ 1 $ 15 Noncurrent Gross amounts recognized $ 260 $ 3 $ 27 $ 12 $ — $ 5 $ — $ 107 Gross amounts offset (5) (1) (4) (4) — — — — Net amounts presented in Other Noncurrent Liabilities: Other $ 255 $ 2 $ 23 $ 8 $ — $ 5 $ — $ 107 Derivative Liabilities December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Current Gross amounts recognized $ 118 $ 39 $ 51 $ 27 $ 24 $ 1 $ 1 $ 7 Gross amounts offset (24) — (24) — (24) — — — Net amounts presented in Current Liabilities: Other $ 94 $ 39 $ 27 $ 27 $ — $ 1 $ 1 $ 7 Noncurrent Gross amounts recognized $ 182 $ 10 $ 37 $ 22 $ — $ 5 $ — $ 110 Gross amounts offset — — — — — — — — Net amounts presented in Other Noncurrent Liabilities: Other $ 182 $ 10 $ 37 $ 22 $ — $ 5 $ — $ 110
Derivative Contracts with Contingent Credit Features	The following tables show information with respect to derivative contracts that are in a net liability position and contain objective credit-risk-related payment provisions. December 31, 2020 Duke Duke Duke Energy Progress Energy (in millions) Energy Carolinas Energy Progress Aggregate fair value of derivatives in a net liability position $ 24 $ 9 $ 14 $ 14 Fair value of collateral already posted — — — — Additional cash collateral or letters of credit in the event credit-risk-related contingent features were triggered 24 9 14 14 December 31, 2019 Duke Duke Duke Energy Progress Energy (in millions) Energy Carolinas Energy Progress Aggregate fair value of derivatives in a net liability position $ 79 $ 35 $ 44 $ 44 Fair value of collateral already posted — — — — Additional cash collateral or letters of credit in the event credit-risk-related contingent features were triggered 79 35 44 44

Investments in Debt and Equit_2

Investments in Debt and Equity Securities (Tables)	12 Months Ended
	Dec. 31, 2020
Investment [Line Items]
Summary of Investments in Debt and Equity Securities	The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS. December 31, 2020 December 31, 2019 Gross Gross Gross Gross Unrealized Unrealized Unrealized Unrealized Holding Holding Estimated Holding Holding Estimated (in millions) Gains Losses Fair Value Gains Losses Fair Value NDTF Cash and cash equivalents $ — $ — $ 177 $ — $ — $ 101 Equity securities 4,138 54 6,235 3,523 55 5,661 Corporate debt securities 76 1 806 37 1 603 Municipal bonds 22 — 370 13 — 368 U.S. government bonds 51 — 1,361 33 1 1,256 Other debt securities 8 — 180 3 — 141 Total NDTF Investments $ 4,295 $ 55 $ 9,129 $ 3,609 $ 57 $ 8,130 Other Investments Cash and cash equivalents $ — $ — $ 127 $ — $ — $ 52 Equity securities 79 — 146 57 — 122 Corporate debt securities 8 — 110 3 — 67 Municipal bonds 5 — 86 4 — 94 U.S. government bonds — — 42 2 — 41 Other debt securities — — 47 — — 56 Total Other Investments $ 92 $ — $ 558 $ 66 $ — $ 432 Total Investments $ 4,387 $ 55 $ 9,687 $ 3,675 $ 57 $ 8,562
Investments Classified by Contractual Maturity Date	The table below summarizes the maturity date for debt securities. (in millions) December 31, 2020 Due in one year or less $ 149 Due after one through five years 922 Due after five through 10 years 671 Due after 10 years 1,260 Total $ 3,002
Schedule of Realized Gain (Loss)	Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the years ended December 31, 2020, 2019 and 2018, were as follows. Years Ended December 31, (in millions) 2020 2019 2018 FV-NI: Realized gains $ 366 $ 172 $ 168 Realized losses 174 151 126 AFS: Realized gains 96 94 22 Realized losses 51 67 51
Duke Energy Carolinas
Investment [Line Items]
Summary of Investments in Debt and Equity Securities	The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS. December 31, 2020 December 31, 2019 Gross Gross Gross Gross Unrealized Unrealized Unrealized Unrealized Holding Holding Estimated Holding Holding Estimated (in millions) Gains Losses Fair Value Gains Losses Fair Value NDTF Cash and cash equivalents $ — $ — $ 30 $ — $ — $ 21 Equity securities 2,442 23 3,685 1,914 8 3,154 Corporate debt securities 49 1 510 21 1 361 Municipal bonds 6 — 91 3 — 96 U.S. government bonds 25 — 475 16 1 578 Other debt securities 7 — 174 3 — 137 Total NDTF Investments $ 2,529 $ 24 $ 4,965 $ 1,957 $ 10 $ 4,347
Investments Classified by Contractual Maturity Date	The table below summarizes the maturity date for debt securities. (in millions) December 31, 2020 Due in one year or less $ 14 Due after one through five years 299 Due after five through 10 years 279 Due after 10 years 658 Total $ 1,250
Schedule of Realized Gain (Loss)	Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the years ended December 31, 2020, 2019 and 2018, were as follows. Years Ended December 31, (in millions) 2020 2019 2018 FV-NI: Realized gains $ 64 $ 113 $ 89 Realized losses 99 107 73 AFS: Realized gains 60 55 19 Realized losses 37 38 35
Progress Energy
Investment [Line Items]
Summary of Investments in Debt and Equity Securities	The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS. December 31, 2020 December 31, 2019 Gross Gross Gross Gross Unrealized Unrealized Unrealized Unrealized Holding Holding Estimated Holding Holding Estimated (in millions) Gains Losses Fair Value Gains Losses Fair Value NDTF Cash and cash equivalents $ — $ — $ 147 $ — $ — $ 80 Equity securities 1,696 31 2,550 1,609 47 2,507 Corporate debt securities 27 — 296 16 — 242 Municipal bonds 16 — 279 10 — 272 U.S. government bonds 26 — 886 17 — 678 Other debt securities 1 — 6 — — 4 Total NDTF Investments $ 1,766 $ 31 $ 4,164 $ 1,652 $ 47 $ 3,783 Other Investments Cash and cash equivalents $ — $ — $ 106 $ — $ — $ 49 Municipal bonds 3 — 26 3 — 51 Total Other Investments $ 3 $ — $ 132 $ 3 $ — $ 100 Total Investments $ 1,769 $ 31 $ 4,296 $ 1,655 $ 47 $ 3,883
Investments Classified by Contractual Maturity Date	The table below summarizes the maturity date for debt securities. (in millions) December 31, 2020 Due in one year or less $ 109 Due after one through five years 567 Due after five through 10 years 298 Due after 10 years 519 Total $ 1,493
Schedule of Realized Gain (Loss)	Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the years ended December 31, 2020, 2019 and 2018, were as follows. Years Ended December 31, (in millions) 2020 2019 2018 FV-NI: Realized gains $ 302 $ 59 $ 79 Realized losses 75 44 53 AFS: Realized gains 24 36 3 Realized losses 13 29 15
Duke Energy Progress
Investment [Line Items]
Summary of Investments in Debt and Equity Securities	The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS. December 31, 2020 December 31, 2019 Gross Gross Gross Gross Unrealized Unrealized Unrealized Unrealized Holding Holding Estimated Holding Holding Estimated (in millions) Gains Losses Fair Value Gains Losses Fair Value NDTF Cash and cash equivalents $ — $ — $ 76 $ — $ — $ 53 Equity securities 1,617 31 2,459 1,258 21 2,077 Corporate debt securities 27 — 296 16 — 242 Municipal bonds 16 — 279 10 — 272 U.S. government bonds 26 — 412 16 — 403 Other debt securities 1 — 6 — — 4 Total NDTF Investments $ 1,687 $ 31 $ 3,528 $ 1,300 $ 21 $ 3,051 Other Investments Cash and cash equivalents $ — $ — $ 1 $ — $ — $ 2 Total Other Investments $ — $ — $ 1 $ — $ — $ 2 Total Investments $ 1,687 $ 31 $ 3,529 $ 1,300 $ 21 $ 3,053
Investments Classified by Contractual Maturity Date	The table below summarizes the maturity date for debt securities. (in millions) December 31, 2020 Due in one year or less $ 21 Due after one through five years 259 Due after five through 10 years 210 Due after 10 years 503 Total $ 993
Schedule of Realized Gain (Loss)	Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the years ended December 31, 2020, 2019 and 2018, were as follows. Years Ended December 31, (in millions) 2020 2019 2018 FV-NI: Realized gains $ 52 $ 38 $ 68 Realized losses 59 33 48 AFS: Realized gains 24 7 2 Realized losses 13 5 10
Duke Energy Florida
Investment [Line Items]
Summary of Investments in Debt and Equity Securities	The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS. December 31, 2020 December 31, 2019 Gross Gross Gross Gross Unrealized Unrealized Unrealized Unrealized Holding Holding Estimated Holding Holding Estimated (in millions) Gains Losses Fair Value Gains Losses Fair Value NDTF Cash and cash equivalents $ — $ — $ 71 $ — $ — $ 27 Equity securities 79 — 91 351 26 430 U.S. government bonds — — 474 1 — 275 Total NDTF Investments (a) $ 79 $ — $ 636 $ 352 $ 26 $ 732 Other Investments Cash and cash equivalents $ — $ — $ 1 $ — $ — $ 4 Municipal bonds 3 — 26 3 — 51 Total Other Investments $ 3 $ — $ 27 $ 3 $ — $ 55 Total Investments $ 82 $ — $ 663 $ 355 $ 26 $ 787 (a) During the years ended December 31, 2020, and 2019, Duke Energy Florida continued to receive reimbursements from the NDTF for costs related to ongoing decommissioning activity of the Crystal River Unit 3.
Investments Classified by Contractual Maturity Date	The table below summarizes the maturity date for debt securities. (in millions) December 31, 2020 Due in one year or less $ 88 Due after one through five years 308 Due after five through 10 years 88 Due after 10 years 16 Total $ 500
Schedule of Realized Gain (Loss)	Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the years ended December 31, 2020, 2019 and 2018, were as follows. Years Ended December 31, (in millions) 2020 2019 2018 FV-NI: Realized gains $ 250 $ 21 $ 11 Realized losses 16 11 5 AFS: Realized gains — 29 1 Realized losses — 24 5
Duke Energy Indiana
Investment [Line Items]
Summary of Investments in Debt and Equity Securities	The following table presents the estimated fair value of investments in debt and equity securities; equity investments are measured at FV-NI and debt investments are classified as AFS. December 31, 2020 December 31, 2019 Gross Gross Gross Gross Unrealized Unrealized Unrealized Unrealized Holding Holding Estimated Holding Holding Estimated (in millions) Gains Losses Fair Value Gains Losses Fair Value Investments Cash and cash equivalents $ — $ — $ 1 $ — $ — $ — Equity securities 58 — 97 43 — 81 Corporate debt securities — — 3 — — 6 Municipal bonds 1 — 38 1 — 36 U.S. government bonds — — 4 — — 2 Total Investments $ 59 $ — $ 143 $ 44 $ — $ 125
Investments Classified by Contractual Maturity Date	The table below summarizes the maturity date for debt securities. (in millions) December 31, 2020 Due in one year or less $ 3 Due after one through five years 17 Due after five through 10 years 10 Due after 10 years 15 Total $ 45

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Measurement Amounts For Assets And Liabilities	The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Consolidated Balance Sheets. Derivative amounts in the tables below for all Duke Energy Registrants exclude cash collateral, which is disclosed in Note 14. See Note 15 for additional information related to investments by major security type for the Duke Energy Registrants. December 31, 2020 (in millions) Total Fair Value Level 1 Level 2 Level 3 Not Categorized NDTF cash and cash equivalents $ 177 $ 177 $ — $ — $ — NDTF equity securities 6,235 6,189 — — 46 NDTF debt securities 2,717 874 1,843 — — Other equity securities 146 146 — — — Other debt securities 285 37 248 — — Other cash and cash equivalents 127 127 — — — Derivative assets 61 1 53 7 — Total assets 9,748 7,551 2,144 7 46 Derivative liabilities (324) — (240) (84) — Net assets (liabilities) $ 9,424 $ 7,551 $ 1,904 $ (77) $ 46 December 31, 2019 (in millions) Total Fair Value Level 1 Level 2 Level 3 Not Categorized NDTF cash and cash equivalents $ 101 $ 101 $ — $ — $ — NDTF equity securities 5,684 5,633 — — 51 NDTF debt securities 2,368 725 1,643 — — Other equity securities 122 122 — — — Other debt securities 258 39 219 — — Other cash and cash equivalents 52 52 — — — Derivative assets 25 3 7 15 — Total assets 8,610 6,675 1,869 15 51 NDTF equity security contracts (23) — (23) — — Derivative liabilities (277) (15) (145) (117) — Net assets (liabilities) $ 8,310 $ 6,660 $ 1,701 $ (102) $ 51
Reconciliation Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Unobservable Inputs	The following table provides reconciliations of beginning and ending balances of assets and liabilities measured at fair value using Level 3 measurements. Derivatives (net) Years Ended December 31, (in millions) 2020 2019 Balance at beginning of period $ (102) $ (113) Total pretax realized or unrealized losses included in comprehensive income (84) — Purchases, sales, issuances and settlements: Purchases 14 37 Settlements (19) (44) Net transfers Out of Level 3 (a) 117 — Total (losses) gains included on the Consolidated Balance Sheet (3) 18 Balance at end of period $ (77) $ (102) (a) Transferred from Level 3 to Level 2 because observable market data became available.
Quantitative Information Table - Level 3	The following tables include quantitative information about the Duke Energy Registrants' derivatives classified as Level 3. December 31, 2020 Weighted Fair Value Average Investment Type (in millions) Valuation Technique Unobservable Input Range Range Duke Energy Electricity contracts $ (84) Discounted cash flow Forward electricity curves – price per MWh $ 14.68 – $ 151.84 $ 28.84 Duke Energy Ohio FTRs 1 RTO auction pricing FTR price – per MWh 0.25 – 1.68 0.79 Duke Energy Indiana FTRs 6 RTO auction pricing FTR price – per MWh (2.40) – 7.41 1.05 Duke Energy Total Level 3 derivatives $ (77) December 31, 2019 Weighted Fair Value Average Investment Type (in millions) Valuation Technique Unobservable Input Range Range Duke Energy Ohio FTRs $ 4 RTO auction pricing FTR price – per MWh $ 0.59 – $ 3.47 $ 2.07 Duke Energy Indiana FTRs 11 RTO auction pricing FTR price – per MWh (0.66) – 9.24 1.15 Piedmont Natural gas contracts (117) Discounted cash flow Forward natural gas curves – price per MMBtu 1.59 – 2.46 1.91 Duke Energy Total Level 3 derivatives $ (102)
Schedule of Long-term debt Fair Value	The fair value and book value of long-term debt, including current maturities, is summarized in the following table. Estimates determined are not necessarily indicative of amounts that could have been settled in current markets. Fair value of long-term debt uses Level 2 measurements. December 31, 2020 December 31, 2019 (in millions) Book Value Fair Value Book Value Fair Value Duke Energy (a) $ 59,863 $ 69,292 $ 58,126 $ 63,062 Duke Energy Carolinas 12,218 14,917 11,900 13,516 Progress Energy 19,264 23,470 19,634 22,291 Duke Energy Progress 9,258 10,862 9,058 9,934 Duke Energy Florida 7,915 9,756 7,987 9,131 Duke Energy Ohio 3,089 3,650 2,619 2,964 Duke Energy Indiana 4,091 5,204 4,057 4,800 Piedmont 2,780 3,306 2,384 2,642 (a) Book value of long-term debt includes $1.3 billion as of December 31, 2020, and $1.5 billion as of December 31, 2019, of unamortized debt discount and premium, net in purchase accounting adjustments related to the mergers with Progress Energy and Piedmont that are excluded from fair value of long-term debt.
Duke Energy Carolinas
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Measurement Amounts For Assets And Liabilities	The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Consolidated Balance Sheets. December 31, 2020 (in millions) Total Fair Value Level 1 Level 2 Not Categorized NDTF cash and cash equivalents $ 30 $ 30 $ — $ — NDTF equity securities 3,685 3,639 — 46 NDTF debt securities 1,250 192 1,058 — Derivative assets 20 — 20 — Total assets 4,985 3,861 1,078 46 Derivative liabilities (20) — (20) — Net assets $ 4,965 $ 3,861 $ 1,058 $ 46 December 31, 2019 (in millions) Total Fair Value Level 1 Level 2 Not Categorized NDTF cash and cash equivalents $ 21 $ 21 $ — $ — NDTF equity securities 3,154 3,103 — 51 NDTF debt securities 1,172 206 966 — Total assets 4,347 3,330 966 51 Derivative liabilities (49) — (49) — Net assets $ 4,298 $ 3,330 $ 917 $ 51
Progress Energy
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Measurement Amounts For Assets And Liabilities	The following table provides recorded balances for assets and liabilities measured at fair value on a recurring basis on the Consolidated Balance Sheets. December 31, 2020 December 31, 2019 (in millions) Total Fair Value Level 1 Level 2 Total Fair Value Level 1 Level 2 NDTF cash and cash equivalents $ 147 $ 147 $ — $ 80 $ 80 $ — NDTF equity securities 2,550 2,550 — 2,530 2,530 — NDTF debt securities 1,467 682 785 1,196 519 677 Other debt securities 26 — 26 51 — 51 Other cash and cash equivalents 106 106 49 49 — Derivative assets 33 — 33 7 — 7 Total assets 4,329 3,485 844 3,913 3,178 735 NDTF equity security contracts — — — (23) — (23) Derivative liabilities (29) — (29) (65) — (65) Net assets $ 4,300 $ 3,485 $ 815 $ 3,825 $ 3,178 $ 647
Duke Energy Progress
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Measurement Amounts For Assets And Liabilities	The following table provides recorded balances for assets and liabilities measured at fair value on a recurring basis on the Consolidated Balance Sheets. December 31, 2020 December 31, 2019 (in millions) Total Fair Value Level 1 Level 2 Total Fair Value Level 1 Level 2 NDTF cash and cash equivalents $ 76 $ 76 $ — $ 53 $ 53 $ — NDTF equity securities 2,459 2,459 — 2,077 2,077 — NDTF debt securities 993 237 756 921 244 677 Other cash and cash equivalents 1 1 — 2 2 — Derivative assets 33 — 33 — — — Total assets 3,562 2,773 789 3,053 2,376 677 Derivative liabilities (14) — (14) (49) — (49) Net assets $ 3,548 $ 2,773 $ 775 $ 3,004 $ 2,376 $ 628
Duke Energy Florida
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Measurement Amounts For Assets And Liabilities	The following table provides recorded balances for assets and liabilities measured at fair value on a recurring basis on the Consolidated Balance Sheets. December 31, 2020 December 31, 2019 (in millions) Total Fair Value Level 1 Level 2 Total Fair Value Level 1 Level 2 NDTF cash and cash equivalents $ 71 $ 71 $ — $ 27 $ 27 $ — NDTF equity securities 91 91 — 453 453 — NDTF debt securities 474 445 29 275 275 — Other debt securities 26 — 26 51 — 51 Other cash and cash equivalents 1 1 — 4 4 — Derivative assets — — — 7 — 7 Total assets 663 608 55 817 759 58 NDTF equity security contracts — — — (23) — (23) Derivative liabilities — — — (1) — (1) Net assets $ 663 $ 608 $ 55 $ 793 $ 759 $ 34
Duke Energy Indiana
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Measurement Amounts For Assets And Liabilities	The following table provides recorded balances for assets and liabilities measured at fair value on a recurring basis on the Consolidated Balance Sheets. December 31, 2020 December 31, 2019 (in millions) Total Fair Value Level 1 Level 2 Level 3 Total Fair Value Level 1 Level 2 Level 3 Other equity securities $ 97 $ 97 $ — $ — $ 81 $ 81 $ — $ — Other debt securities 45 — 45 — 44 — 44 — Other cash equivalents 1 1 — — — — — — Derivative assets 6 — — 6 13 2 — 11 Total assets 149 98 45 6 138 83 44 11 Derivative liabilities (1) (1) — — (1) (1) — — Total assets $ 148 $ 97 $ 45 $ 6 $ 137 $ 82 $ 44 $ 11
Reconciliation Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Unobservable Inputs	The following table provides a reconciliation of beginning and ending balances of assets and liabilities measured at fair value using Level 3 measurements. Derivatives (net) Years Ended December 31, (in millions) 2020 2019 Balance at beginning of period $ 11 $ 22 Purchases, sales, issuances and settlements: Purchases 10 28 Settlements (13) (36) Total losses included on the Consolidated Balance Sheet (2) (3) Balance at end of period $ 6 $ 11
Piedmont
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Measurement Amounts For Assets And Liabilities	The following table provides recorded balances for assets and liabilities measured at fair value on a recurring basis on the Consolidated Balance Sheets. December 31, 2020 December 31, 2019 (in millions) Total Fair Value Level 1 Level 2 Total Fair Value Level 1 Level 3 Derivative assets $ 1 $ 1 $ — $ 1 $ 1 $ — Derivative liabilities (122) — (122) (117) — (117) Net (liabilities) assets $ (121) $ 1 $ (122) $ (116) $ 1 $ (117)
Reconciliation Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Unobservable Inputs	The following table provides a reconciliation of beginning and ending balances of assets and liabilities measured at fair value using Level 3 measurements. Derivatives (net) Years Ended December 31, (in millions) 2020 2019 Balance at beginning of period $ (117) $ (141) Net transfers Out of Level 3 (a) 117 — Total gains and settlements — 24 Balance at end of period $ — $ (117) (a) Transferred from Level 3 to Level 2 because observable market data became available.

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	12 Months Ended
	Dec. 31, 2020
Consolidated VIEs
Variable Interest Entity [Line Items]
Schedule Of Variable Interest Entities	The following table summarizes the amounts and expiration dates of the credit facilities and associated restricted receivables described above. Duke Energy Duke Energy Duke Energy Duke Energy Carolinas Progress Florida (in millions) CRC DERF DEPR DEFR Expiration date February 2023 December 2022 April 2023 April 2021 Credit facility amount $ 350 $ 475 $ 350 $ 250 Amounts borrowed at December 31, 2020 350 364 250 250 Amounts borrowed at December 31, 2019 350 474 325 250 Restricted Receivables at December 31, 2020 547 696 500 397 Restricted Receivables at December 31, 2019 522 642 489 336
Consolidated VIEs | DEFPF
Variable Interest Entity [Line Items]
Schedule Of Variable Interest Entities	The following table summarizes the impact of DEFPF on Duke Energy Florida's Consolidated Balance Sheets. December 31, (in millions) 2020 2019 Receivables of VIEs $ 4 $ 5 Regulatory Assets: Current 53 52 Current Assets: Other 39 39 Other Noncurrent Assets: Regulatory assets 937 989 Current Liabilities: Other 10 10 Current maturities of long-term debt 55 54 Long-Term Debt 1,002 1,057
Consolidated VIEs | Commercial Renewables
Variable Interest Entity [Line Items]
Schedule Of Variable Interest Entities	The table below presents material balances reported on Duke Energy's Consolidated Balance Sheets related to Commercial Renewables VIEs. December 31, (in millions) 2020 2019 Current Assets: Other $ 257 $ 203 Property, Plant and Equipment: Cost 6,394 5,747 Accumulated depreciation and amortization (1,242) (1,041) Other Noncurrent Assets: Other 67 106 Current maturities of long-term debt 167 162 Long-Term Debt 1,569 1,541 Other Noncurrent Liabilities: AROs 148 127 Other Noncurrent Liabilities: Other 316 228
Non-consolidated VIEs
Variable Interest Entity [Line Items]
Schedule Of Variable Interest Entities	The following tables summarize the impact of non-consolidated VIEs on the Consolidated Balance Sheets. December 31, 2020 Duke Energy Duke Duke Pipeline Commercial Energy Energy (in millions) Investments Renewables Total Ohio Indiana Receivables from affiliated companies $ — $ — $ — $ 83 $ 110 Investments in equity method unconsolidated affiliates — 530 530 — — Other noncurrent assets 31 — 31 — — Total assets $ 31 $ 530 $ 561 $ 83 $ 110 Other current liabilities 928 5 933 — — Other noncurrent liabilities 8 10 18 — — Total liabilities $ 936 $ 15 $ 951 $ — $ — Net assets (liabilities) $ (905) $ 515 $ (390) $ 83 $ 110 December 31, 2019 Duke Energy Duke Duke Pipeline Commercial Energy Energy (in millions) Investments Renewables Total Ohio Indiana Receivables from affiliated companies $ — $ (1) $ (1) $ 64 $ 77 Investments in equity method unconsolidated affiliates 1,179 300 1,479 — — Total assets $ 1,179 $ 299 $ 1,478 $ 64 $ 77 Taxes accrued (1) — (1) — — Other current liabilities — 4 4 — — Deferred income taxes 59 — 59 — — Other noncurrent liabilities — 11 11 — — Total liabilities $ 58 $ 15 $ 73 $ — $ — Net assets $ 1,121 $ 284 $ 1,405 $ 64 $ 77
Non-consolidated VIEs | CRC
Variable Interest Entity [Line Items]
Schedule Of Variable Interest Entities	Key assumptions used in estimating fair value are detailed in the following table. Duke Energy Ohio Duke Energy Indiana 2020 2019 2020 2019 Anticipated credit loss ratio 0.5 % 0.6 % 0.3 % 0.3 % Discount rate 1.6 % 3.3 % 1.6 % 3.3 % Receivable turnover rate 13.4 % 13.4 % 11.3 % 11.5 % The following table shows the gross and net receivables sold. Duke Energy Ohio Duke Energy Indiana December 31, December 31, (in millions) 2020 2019 2020 2019 Receivables sold $ 270 $ 253 $ 344 $ 307 Less: Retained interests 83 64 110 77 Net receivables sold $ 187 $ 189 $ 234 $ 230 The following table shows sales and cash flows related to receivables sold. Duke Energy Ohio Duke Energy Indiana Years Ended December 31, Years Ended December 31, (in millions) 2020 2019 2018 2020 2019 2018 Sales Receivables sold $ 1,905 $ 1,979 $ 1,987 $ 2,631 $ 2,837 $ 2,842 Loss recognized on sale 10 14 13 12 17 16 Cash flows Cash proceeds from receivables sold 1,875 1,993 1,967 2,586 2,860 2,815 Collection fees received 1 1 1 1 1 1 Return received on retained interests 4 6 6 5 9 9

Revenue (Tables)

Revenue (Tables)	12 Months Ended
	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction	Supplemental requirements contracts that include contracted blocks of energy and capacity at contractually fixed prices have the following estimated remaining performance obligations: Remaining Performance Obligations (in millions) 2021 2022 2023 2024 2025 Thereafter Total Progress Energy $ 93 $ 107 $ 44 $ 45 $ 7 $ 51 $ 347 Duke Energy Progress 8 8 8 8 — — 32 Duke Energy Florida 85 99 36 37 7 51 315 Duke Energy Indiana 5 — 7 12 12 24 60 Remaining Performance Obligations (in millions) 2021 2022 2023 2024 2025 Thereafter Total Piedmont $ 65 $ 64 $ 61 $ 59 $ 58 $ 319 $ 626
Disaggregation of Revenue	Disaggregated revenues are presented as follows: Year Ended December 31, 2020 Duke Duke Duke Duke Duke (in millions) Duke Energy Progress Energy Energy Energy Energy By market or type of customer Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Electric Utilities and Infrastructure Residential $ 9,806 $ 2,997 $ 5,017 $ 2,059 $ 2,958 $ 726 $ 1,064 $ — General 6,194 2,233 2,779 1,312 1,467 442 740 — Industrial 2,859 1,137 901 649 252 137 683 — Wholesale 1,864 380 1,228 1,034 194 32 224 — Other revenues 914 281 596 294 302 82 72 — Total Electric Utilities and Infrastructure revenue from contracts with customers $ 21,637 $ 7,028 $ 10,521 $ 5,348 $ 5,173 $ 1,419 $ 2,783 $ — Gas Utilities and Infrastructure Residential $ 930 $ — $ — $ — $ — $ 300 $ — $ 630 Commercial 446 — — — — 117 — 329 Industrial 127 — — — — 17 — 110 Power Generation — — — — — — — 34 Other revenues 87 — — — — 17 — 70 Total Gas Utilities and Infrastructure revenue from contracts with customers $ 1,590 $ — $ — $ — $ — $ 451 $ — $ 1,173 Commercial Renewables Revenue from contracts with customers $ 227 $ — $ — $ — $ — $ — $ — $ — Other Revenue from contracts with customers $ 26 $ — $ — $ — $ — $ — $ — $ — Total revenue from contracts with customers $ 23,480 $ 7,028 $ 10,521 $ 5,348 $ 5,173 $ 1,870 $ 2,783 $ 1,173 Other revenue sources (a) $ 388 $ (13) $ 106 $ 74 $ 15 $ (12) $ 12 $ 124 Total revenues $ 23,868 $ 7,015 $ 10,627 $ 5,422 $ 5,188 $ 1,858 $ 2,795 $ 1,297 (a) Other revenue sources include revenues from leases, derivatives and alternative revenue programs that are not considered revenues from contracts with customers. Alternative revenue programs in certain jurisdictions include regulatory mechanisms that periodically adjust for over or under collection of related revenues. Year Ended December 31, 2019 Duke Duke Duke Duke Duke (in millions) Duke Energy Progress Energy Energy Energy Energy By market or type of customer Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Electric Utilities and Infrastructure Residential $ 9,863 $ 3,044 $ 4,998 $ 2,144 $ 2,854 $ 733 $ 1,087 $ — General 6,431 2,244 2,935 1,368 1,567 451 802 — Industrial 3,071 1,215 934 675 259 147 774 — Wholesale 2,212 462 1,468 1,281 187 46 235 — Other revenues 770 276 548 317 231 80 89 — Total Electric Utilities and Infrastructure revenue from contracts with customers $ 22,347 $ 7,241 $ 10,883 $ 5,785 $ 5,098 $ 1,457 $ 2,987 $ — Gas Utilities and Infrastructure Residential $ 976 $ — $ — $ — $ — $ 315 $ — $ 661 Commercial 508 — — — — 130 — 378 Industrial 141 — — — — 19 — 122 Power Generation — — — — — — — 51 Other revenues 129 — — — — 19 — 110 Total Gas Utilities and Infrastructure revenue from contracts with customers $ 1,754 $ — $ — $ — $ — $ 483 $ — $ 1,322 Commercial Renewables Revenue from contracts with customers $ 223 $ — $ — $ — $ — $ — $ — $ — Other Revenue from contracts with customers $ 24 $ — $ — $ — $ — $ — $ — $ — Total revenue from contracts with customers $ 24,348 $ 7,241 $ 10,883 $ 5,785 $ 5,098 $ 1,940 $ 2,987 $ 1,322 Other revenue sources (a) $ 731 $ 154 $ 319 $ 172 $ 133 $ — $ 17 $ 59 Total revenues $ 25,079 $ 7,395 $ 11,202 $ 5,957 $ 5,231 $ 1,940 $ 3,004 $ 1,381 (a) Other revenue sources include revenues from leases, derivatives and alternative revenue programs that are not considered revenues from contracts with customers. Alternative revenue programs in certain jurisdictions include regulatory mechanisms that periodically adjust for over or under collection of related revenues. Year Ended December 31, 2018 Duke Duke Duke Duke Duke (in millions) Duke Energy Progress Energy Energy Energy Energy By market or type of customer Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Electric Utilities and Infrastructure Residential $ 9,587 $ 2,981 $ 4,785 $ 2,019 $ 2,766 $ 743 $ 1,076 $ — General 6,127 2,119 2,809 1,280 1,529 422 778 — Industrial 2,974 1,180 904 642 262 131 760 — Wholesale 2,324 508 1,462 1,303 159 57 298 — Other revenues 717 320 502 320 182 73 91 — Total Electric Utilities and Infrastructure revenue from contracts with customers $ 21,729 $ 7,108 $ 10,462 $ 5,564 $ 4,898 $ 1,426 $ 3,003 $ — Gas Utilities and Infrastructure Residential $ 1,000 $ — $ — $ — $ — $ 331 $ — $ 669 Commercial 514 — — — — 135 — 378 Industrial 147 — — — — 18 — 128 Power Generation — — — — — — — 54 Other revenues 139 — — — — 19 — 120 Total Gas Utilities and Infrastructure revenue from contracts with customers $ 1,800 $ — $ — $ — $ — $ 503 $ — $ 1,349 Commercial Renewables Revenue from contracts with customers $ 209 $ — $ — $ — $ — $ — $ — $ — Other Revenue from contracts with customers $ 19 $ — $ — $ — $ — $ 1 $ — $ — Total revenue from contracts with customers $ 23,757 $ 7,108 $ 10,462 $ 5,564 $ 4,898 $ 1,930 $ 3,003 $ 1,349 Other revenue sources (a) $ 764 $ 192 $ 266 $ 135 $ 123 $ 27 $ 56 $ 26 Total revenues $ 24,521 $ 7,300 $ 10,728 $ 5,699 $ 5,021 $ 1,957 $ 3,059 $ 1,375 (a) Other revenue sources include revenues from leases, derivatives and alternative revenue programs that are not considered revenues from contracts with customers. Alternative revenue programs in certain jurisdictions include regulatory mechanisms that periodically adjust for over or under collection of related revenues.
Accounts Receivable, Allowance for Credit Loss	The following table presents the reserve for credit losses for trade and other receivables based on adoption of the new standard. Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Balance at December 31, 2019 $ 76 $ 10 $ 16 $ 8 $ 7 $ 4 $ 3 $ 6 Cumulative Change in Accounting Principle 5 1 2 1 1 — — 1 Write-Offs (58) (13) (23) (8) (14) — — (6) Credit Loss Expense 75 13 29 9 20 — — 11 Other Adjustments 48 12 13 13 — — — — Balance at December 31, 2020 $ 146 $ 23 $ 37 $ 23 $ 14 $ 4 $ 3 $ 12
Financing Receivable, Past Due	The aging of trade receivables is presented in the table below. Duke Energy considers receivables greater than 30 days outstanding past due. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Unbilled Receivables $ 969 $ 328 $ 283 $ 167 $ 116 $ 2 $ 16 $ 86 0-30 days 1,789 445 707 398 307 60 26 149 30-60 days 185 80 54 25 29 8 3 8 60-90 days 22 1 10 4 6 2 1 3 90+ days 119 16 32 9 23 30 12 9 Deferred Payment Arrangements (a) 215 96 80 52 28 — — 7 Trade and Other Receivables $ 3,299 $ 966 $ 1,166 $ 655 $ 509 $ 102 $ 58 $ 262 (a) Due to certain customer financial hardships created by the COVID-19 pandemic and resulting stay-at-home orders, Duke Energy permitted customers to defer payment of past-due amounts through an installment payment plan over a period of several months.
Schedule Of Unbilled Revenues With Restricted Receivables	Unbilled revenues are included within Receivables and Receivables of VIEs on the Consolidated Balance Sheets as shown in the following table. December 31, (in millions) 2020 2019 Duke Energy $ 969 $ 843 Duke Energy Carolinas 328 298 Progress Energy 283 217 Duke Energy Progress 167 122 Duke Energy Florida 116 95 Duke Energy Ohio 2 1 Duke Energy Indiana 16 16 Piedmont 86 78 December 31, (in millions) 2020 2019 Duke Energy Ohio $ 87 $ 82 Duke Energy Indiana 134 115

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Schedule Of Earnings Per Share	The following table presents Duke Energy’s basic and diluted EPS calculations, the weighted average number of common shares outstanding and common and preferred share dividends declared. Years Ended December 31, (in millions, except per share amounts) 2020 2019 2018 Net Income available to Duke Energy common stockholders $ 1,270 $ 3,707 $ 2,666 Less: Income (Loss) from discontinued operations 7 (7) 19 Accumulated preferred stock dividends adjustment 1 (15) — Less: Impact of participating securities 2 5 5 Income from continuing operations available to Duke Energy common stockholders $ 1,262 $ 3,694 $ 2,642 Weighted average common shares outstanding – basic 737 729 708 Equity forwards 1 — — Weighted average common shares outstanding – diluted 738 729 708 EPS from continuing operations available to Duke Energy common stockholders Basic and Diluted $ 1.71 $ 5.07 $ 3.73 Potentially dilutive items excluded from the calculation (a) 2 2 2 Dividends declared per common share $ 3.82 $ 3.75 $ 3.64 Dividends declared on Series A preferred stock per depositary share $ 1.437 $ 1.03 $ — Dividends declared on Series B preferred stock per share $ 49.292 $ — $ — (a) Performance stock awards were not included in the dilutive securities calculation because the performance measures related to the awards had not been met.

Severance (Tables)

Severance (Tables)	12 Months Ended
	Dec. 31, 2020
Restructuring and Related Activities [Abstract]
Schedule of Severance Expense	The following table presents the direct and allocated severance and related charges accrued for approximately 30 e mployees in 2020, 140 employees in 2019, and 1,900 employees in 2018, by the Duke Energy Registrants within Operation, maintenance and other on the Consolidated Statements of Operations. Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Year Ended December 31, 2020 (a)(b) $ (85) $ (58) $ (28) $ (31) $ 3 $ — $ — $ — Year Ended December 31, 2019 16 8 6 3 3 — 1 1 Year Ended December 31, 2018 187 102 69 52 17 6 7 2 (a) Includes unamortized deferred severance charges of approximately $(86) million, $(57) million, $(29) million and $(29) million for Duke Energy, Duke Energy Carolinas, Progress Energy and Duke Energy Progress, respectively. (b) Includes adjustments associated with 2018 severance charges of approximately $(6) million, $(2) million, $(3) million and $(2) million for Duke Energy, Duke Energy Carolinas, Progress Energy and Duke Energy Progress, respectively.
Schedule of Severance Liability	The table below presents the severance liability for past and ongoing severance plans including the plans described above. Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Balance at December 31, 2019 $ 41 $ 11 $ 13 $ 6 $ 7 $ 1 $ 2 $ — Provision/Adjustments 1 — — (2) 2 (1) — — Cash Reductions (31) (9) (10) (3) (7) — (1) — Balance at December 31, 2020 $ 11 $ 2 $ 3 $ 1 $ 2 $ — $ 1 $ —

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Schedule Of Total Stock-Based Compensation Expense, net of tax	The following table summarizes the total expense recognized by the Duke Energy Registrants, net of tax, for stock-based compensation. Years Ended December 31, (in millions) 2020 2019 2018 Duke Energy $ 61 $ 65 $ 56 Duke Energy Carolinas 22 24 20 Progress Energy 23 24 21 Duke Energy Progress 15 15 13 Duke Energy Florida 9 9 8 Duke Energy Ohio 4 5 4 Duke Energy Indiana 6 6 5 Piedmont 3 3 3
Schedule Of Stock-Based Compensation Expense	Duke Energy's pretax stock-based compensation costs, the tax benefit associated with stock-based compensation expense and stock-based compensation costs capitalized are included in the following table. Years Ended December 31, (in millions) 2020 2019 2018 RSU awards $ 46 $ 44 $ 43 Performance awards 38 45 35 Pretax stock-based compensation cost $ 84 $ 89 $ 78 Stock-based compensation costs capitalized 5 5 5 Stock-based compensation expense $ 79 $ 84 $ 73 Tax benefit associated with stock-based compensation expense $ 18 $ 19 $ 17
Schedule of Share-based Compensation, Restricted Stock Units Award Activity	The following table includes information related to RSU awards. Years Ended December 31, 2020 2019 2018 Shares granted (in thousands) 498 571 649 Fair value (in millions) $ 50 $ 51 $ 49 The following table summarizes information about RSU awards outstanding. Weighted Average Shares Grant Date Fair Value (in thousands) (per share) Outstanding at December 31, 2019 1,010 $ 83 Granted 498 100 Vested (532) 82 Forfeited (37) 92 Outstanding at December 31, 2020 939 93 RSU awards expected to vest 898 93
Schedule of Performance Awards	The following table includes information related to stock-based performance awards. Years Ended December 31, 2020 2019 2018 Shares granted assuming target performance (in thousands) 319 320 372 Fair value (in millions) $ 34 $ 27 $ 27
Schedule of Nonvested Performance-based Units Activity	The following table summarizes information about stock-based performance awards outstanding and assumes payout at the target level. Weighted Average Shares Grant Date Fair Value (in thousands) (per share) Outstanding at December 31, 2019 1,109 $ 80 Granted 319 105 Vested (448) 81 Forfeited (18) 88 Outstanding at December 31, 2020 962 87 Stock-based performance awards expected to vest 937 87

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Pension Plan Contributions	The following table includes information related to the Duke Energy Registrants’ contributions to its qualified defined benefit pension plans. Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Contributions Made: 2020 $ — $ — $ — $ — $ — $ — $ — $ — 2019 77 7 57 4 53 2 2 1 2018 141 46 45 25 20 — 8 —
Fair Value and Allocation of Plan Assets	The following table includes the target asset allocations by asset class at December 31, 2020, and the actual asset allocations for the Duke Energy Master Retirement Trust. Actual Allocation at Target December 31, Allocation 2020 2019 Global equity securities 28 % 30 % 27 % Global private equity securities 1 % 1 % 1 % Debt securities 58 % 55 % 57 % Return seeking debt securities 4 % 5 % 5 % Hedge funds 3 % 3 % 3 % Real estate and cash 6 % 6 % 7 % Total 100 % 100 % 100 % The following table presents target and actual asset allocations for the VEBA trusts at December 31, 2020. Actual Allocation at Target December 31, Allocation 2020 2019 U.S. equity securities 30 % 36 % 35 % Non-U.S. equity securities 6 % 6 % 9 % Real estate 2 % 2 % 2 % Debt securities 45 % 42 % 37 % Cash 17 % 14 % 17 % Total 100 % 100 % 100 % The following tables provide the fair value measurement amounts for the Duke Energy Master Retirement Trust qualified pension and other post-retirement assets. December 31, 2020 Total Fair Not (in millions) Value Level 1 Level 2 Level 3 Categorized (b) Equity securities $ 3,202 $ 3,162 $ — $ — $ 40 Corporate debt securities 4,162 — 4,162 — — Short-term investment funds 397 247 150 — — Partnership interests 97 — — — 97 Hedge funds 198 — — — 198 U.S. government securities 1,164 — 1,164 — — Governments bonds – foreign 73 — 73 — — Cash 98 98 — — — Net pending transactions and other investments 88 34 54 — — Total assets (a) $ 9,479 $ 3,541 $ 5,603 $ — $ 335 (a) Duke Energy Carolinas, Progress Energy, Duke Energy Progress, Duke Energy Florida, Duke Energy Ohio, Duke Energy Indiana and Piedmont were allocated approximately 26%, 32%, 15%, 17%, 5%, 7% and 4%, respectively, of the Duke Energy Master Retirement Trust at December 31, 2020. Accordingly, all amounts included in the table above are allocable to the Subsidiary Registrants using these percentages. (b) Certain investments that are measured at fair value using the net asset value per share practical expedient have not been categorized in the fair value hierarchy. December 31, 2019 Total Fair Not (in millions) Value Level 1 Level 2 Level 3 Categorized (b) Equity securities $ 2,730 $ 2,712 $ — $ — $ 18 Corporate debt securities 3,999 — 3,999 — — Short-term investment funds 545 455 90 — — Partnership interests 104 — — — 104 Hedge funds 206 — — — 206 U.S. government securities 1,231 — 1,231 — — Guaranteed investment contracts 11 — — 11 — Governments bonds – foreign 78 — 78 — — Cash 75 75 — — — Net pending transactions and other investments 46 (43) 89 — — Total assets (a) $ 9,025 $ 3,199 $ 5,487 $ 11 $ 328 (a) Duke Energy Carolinas, Progress Energy, Duke Energy Progress, Duke Energy Florida, Duke Energy Ohio, Duke Energy Indiana and Piedmont were allocated approximately 26%, 31%, 15%, 17%, 5%, 7% and 4%, respectively, of the Duke Energy Master Retirement Trust at December 31, 2019. Accordingly, all amounts included in the table above are allocable to the Subsidiary Registrants using these percentages. (b) Certain investments that are measured at fair value using the net asset value per share practical expedient have not been categorized in the fair value hierarchy. The following tables provide the fair value measurement amounts for VEBA trust assets. December 31, 2020 Total Fair (in millions) Value Level 2 Cash and cash equivalents $ 5 $ 5 Real estate 1 1 Equity securities 23 23 Debt securities 19 19 Total assets $ 48 $ 48 December 31, 2019 Total Fair (in millions) Value Level 2 Cash and cash equivalents $ 9 $ 9 Real estate 1 1 Equity securities 22 22 Debt securities 18 18 Total assets $ 50 $ 50
Master Trust Level 3 Rollforward	The following table provides a reconciliation of beginning and ending balances of Duke Energy Master Retirement Trust qualified pension and other post-retirement assets at fair value on a recurring basis where the determination of fair value includes significant unobservable inputs (Level 3). (in millions) 2020 2019 Balance at January 1 $ 11 $ 27 Sales (12) (18) Total gains and other, net 1 2 Transfer of Level 3 assets to other classifications — — Balance at December 31 $ — $ 11
Employee Savings Plan Matching Contributions	The following table includes pretax employer matching contributions made by Duke Energy and expensed by the Subsidiary Registrants. Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Years ended December 31, 2020 $ 213 $ 67 $ 57 $ 38 $ 19 $ 5 $ 11 $ 13 2019 214 66 58 38 20 5 11 13 2018 213 68 58 40 19 4 10 12
Pension Plan | Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Components of Net Periodic Pension Costs	Components of Net Periodic Pension Costs Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Service cost $ 165 $ 51 $ 48 $ 27 $ 21 $ 5 $ 9 $ 6 Interest cost on projected benefit obligation 269 62 85 38 46 15 22 9 Expected return on plan assets (572) (145) (190) (87) (101) (28) (42) (21) Amortization of actuarial loss 128 28 41 18 23 6 12 9 Amortization of prior service credit (32) (8) (3) (2) (1) — (2) (9) Amortization of settlement charges 18 9 7 6 1 — 1 1 Net periodic pension costs (a)(b) $ (24) $ (3) $ (12) $ — $ (11) $ (2) $ — $ (5) Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Service cost $ 158 $ 49 $ 46 $ 26 $ 20 $ 4 $ 9 $ 5 Interest cost on projected benefit obligation 317 75 100 45 54 18 26 10 Expected return on plan assets (567) (147) (178) (88) (89) (28) (43) (22) Amortization of actuarial loss 108 24 39 15 24 4 8 8 Amortization of prior service credit (32) (8) (3) (2) (1) — (2) (9) Amortization of settlement charges 6 2 1 1 — 2 — — Net periodic pension costs (a)(b) $ (10) $ (5) $ 5 $ (3) $ 8 $ — $ (2) $ (8) Year Ended December 31, 2018 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Service cost $ 182 $ 58 $ 51 $ 29 $ 22 $ 5 $ 11 $ 7 Interest cost on projected benefit obligation 299 72 94 43 50 17 23 11 Expected return on plan assets (559) (147) (178) (85) (91) (28) (42) (22) Amortization of actuarial loss 132 29 44 21 23 5 10 11 Amortization of prior service credit (32) (8) (3) (2) (1) — (2) (10) Net periodic pension costs (a)(b) $ 22 $ 4 $ 8 $ 6 $ 3 $ (1) $ — $ (3) (a) Duke Energy amounts exclude $4 million, $4 million and $5 million for the years ended December 2020, 2019 and 2018, respectively, of regulatory asset amortization resulting from purchase accounting adjustments associated with Duke Energy's merger with Cinergy in April 2006. (b) Duke Energy Ohio amounts exclude $2 million, $2 million and $2 million for the years ended December 2020, 2019 and 2018, respectively, of regulatory asset amortization resulting from purchase accounting adjustments associated with Duke Energy's merger with Cinergy in April 2006.
Amounts Recognized in AOCI and Regulatory Assets and Liabilities	Amounts Recognized in Accumulated Other Comprehensive Income and Regulatory Assets Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Regulatory assets, net increase (decrease) $ (62) $ (39) $ (26) $ (30) $ 4 $ (2) $ 5 $ (1) Accumulated other comprehensive loss (income) Deferred income tax expense (benefit) $ 2 $ — $ 1 $ — $ 1 $ — $ — $ — Amortization of prior year service credit 1 — — — — — — — Amortization of prior year actuarial losses (11) — (1) — (3) — — — Net amount recognized in accumulated other comprehensive income $ (8) $ — $ — $ — $ (2) $ — $ — $ — Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Regulatory assets, net (decrease) increase $ (212) $ (156) $ (79) $ (59) $ (20) $ 12 $ 22 $ — Accumulated other comprehensive (income) loss Deferred income tax expense (benefit) $ 20 $ — $ 1 $ — $ (1) $ — $ — $ — Amortization of prior year service credit 1 — — — — — — — Amortization of prior year actuarial losses (15) — (2) — 3 — — — Net amount recognized in accumulated other comprehensive income $ 6 $ — $ (1) $ — $ 2 $ — $ — $ —
Reconciliation of Funded Status to Net Amount Recognized	Reconciliation of Funded Status to Net Amount Recognized Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Change in Projected Benefit Obligation Obligation at prior measurement date $ 8,321 $ 1,923 $ 2,608 $ 1,170 $ 1,424 $ 481 $ 693 $ 292 Service cost 157 49 46 26 20 4 8 5 Interest cost 269 62 85 38 46 15 22 9 Actuarial loss 433 83 144 50 93 21 46 14 Transfers — 8 (8) (8) — 15 — — Benefits paid (541) (137) (160) (83) (76) (34) (49) (27) Benefits paid – settlements (5) — — — — — (5) — Obligation at measurement date $ 8,634 $ 1,988 $ 2,715 $ 1,193 $ 1,507 $ 502 $ 715 $ 293 Accumulated Benefit Obligation at measurement date $ 8,577 $ 1,989 $ 2,684 $ 1,194 $ 1,476 $ 493 $ 709 $ 294 Change in Fair Value of Plan Assets Plan assets at prior measurement date $ 8,910 $ 2,263 $ 2,898 $ 1,364 $ 1,515 $ 443 $ 667 $ 335 Actual return on plan assets 973 247 319 149 166 48 71 35 Benefits paid (541) (137) (160) (83) (76) (34) (49) (27) Benefits paid – settlements (5) — — — — — (5) — Transfers — 8 (8) (8) — 15 — — Plan assets at measurement date $ 9,337 $ 2,381 $ 3,049 $ 1,422 $ 1,605 $ 472 $ 684 $ 343 Funded status of plan $ 703 $ 393 $ 334 $ 229 $ 98 $ (30) $ (31) $ 50 Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Change in Projected Benefit Obligation Obligation at prior measurement date $ 7,869 $ 1,954 $ 2,433 $ 1,125 $ 1,295 $ 435 $ 618 $ 264 Service cost 150 47 43 25 18 4 8 5 Interest cost 317 75 100 45 54 18 26 10 Actuarial loss 716 101 223 87 135 54 87 33 Transfers — 11 — — — — — — Benefits paid (731) (265) (191) (112) (78) (30) (46) (20) Obligation at measurement date $ 8,321 $ 1,923 $ 2,608 $ 1,170 $ 1,424 $ 481 $ 693 $ 292 Accumulated Benefit Obligation at measurement date $ 8,262 $ 1,923 $ 2,578 $ 1,170 $ 1,392 $ 471 $ 686 $ 292 Change in Fair Value of Plan Assets Plan assets at prior measurement date $ 8,233 $ 2,168 $ 2,606 $ 1,268 $ 1,322 $ 405 $ 611 $ 305 Employer contributions 77 7 57 4 53 2 2 1 Actual return on plan assets 1,331 342 426 204 218 66 100 49 Benefits paid (731) (265) (191) (112) (78) (30) (46) (20) Transfers — 11 — — — — — — Plan assets at measurement date $ 8,910 $ 2,263 $ 2,898 $ 1,364 $ 1,515 $ 443 $ 667 $ 335 Funded status of plan $ 589 $ 340 $ 290 $ 194 $ 91 $ (38) $ (26) $ 43
Amounts Recognized in the Consolidated Balance Sheet	Amounts Recognized in the Consolidated Balance Sheets December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Prefunded pension (a) $ 780 $ 393 $ 379 $ 229 $ 143 $ 58 $ 79 $ 50 Noncurrent pension liability (b) $ 77 $ — $ 45 $ — $ 45 $ 88 $ 110 $ — Net asset (liability) recognized $ 703 $ 393 $ 334 $ 229 $ 98 $ (30) $ (31) $ 50 Regulatory assets $ 1,910 $ 381 $ 691 $ 283 $ 408 $ 110 $ 209 $ 80 Accumulated other comprehensive (income) loss Deferred income tax benefit $ (21) $ — $ — $ — $ — $ — $ — $ — Prior service credit (2) — — — — — — — Net actuarial loss 100 — 2 — — — — — Net amounts recognized in accumulated other comprehensive loss $ 77 $ — $ 2 $ — $ — $ — $ — $ — December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Prefunded pension (a) $ 621 $ 340 $ 322 $ 194 $ 123 $ 38 $ 57 $ 43 Noncurrent pension liability (b) $ 32 $ — $ 32 $ — $ 32 $ 76 $ 83 $ — Net asset recognized $ 589 $ 340 $ 290 $ 194 $ 91 $ (38) $ (26) $ 43 Regulatory assets $ 1,972 $ 420 $ 717 $ 313 $ 404 $ 112 $ 204 $ 81 Accumulated other comprehensive (income) loss Deferred income tax benefit $ (23) $ — $ (1) $ — $ (1) $ — $ — $ — Prior service credit (3) — — — — — — — Net actuarial loss 111 — 3 — 3 — — — Net amounts recognized in accumulated other comprehensive loss $ 85 $ — $ 2 $ — $ 2 $ — $ — $ — Amounts to be recognized in net periodic pension costs in the next year Unrecognized net actuarial loss $ 135 $ 29 $ 43 $ 19 $ 24 $ 7 $ 10 $ 9 Unrecognized prior service credit (32) (8) (3) (2) (1) (1) (2) (9) (a) Included in Other within Other Noncurrent Assets on the Consolidated Balance Sheets. (b) Included in Accrued pension and other post-retirement benefit costs on the Consolidated Balance Sheets.
Information for Plans with Accumulated Benefit Obligation in Excess of Plan Assets	Information for Plans with Accumulated Benefit Obligation in Excess of Plan Assets December 31, 2020 Duke Duke Duke Duke Progress Energy Energy Energy (in millions) Energy Energy Florida Ohio Indiana Projected benefit obligation $ 4,914 $ 828 $ 828 $ 184 $ 293 Accumulated benefit obligation 4,856 796 796 176 285 Fair value of plan assets 4,837 783 783 96 183 December 31, 2019 Duke Duke Energy Energy (in millions) Ohio Indiana Projected benefit obligation $ 155 $ 260 Accumulated benefit obligation 146 252 Fair value of plan assets 79 177
Assumptions Used for Pension Benefits Accounting	The following tables present the assumptions or range of assumptions used for pension benefit accounting. December 31, 2020 2019 2018 Benefit Obligations Discount rate 2.60% 3.30% 4.30% Interest crediting rate 4.00% 4.00% 4.00% Salary increase 3.50 % – 4.00% 3.50 % – 4.00% 3.50 % – 4.00% Net Periodic Benefit Cost Discount rate 3.30% 4.30% 3.60% Interest crediting rate 4.00% 4.00% 4.00% Salary increase 3.50 % – 4.00% 3.50 % – 4.00% 3.50 % – 4.00% Expected long-term rate of return on plan assets 6.85% 6.85% 6.50%
Expected Benefit Payments	Expected Benefit Payments Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Years ending December 31, 2021 $ 667 $ 169 $ 177 $ 94 $ 82 $ 40 $ 53 $ 29 2022 650 170 176 92 83 39 51 25 2023 655 174 181 95 85 38 49 22 2024 644 168 184 96 87 37 49 21 2025 617 163 181 93 88 35 47 19 2025-2029 2,745 677 846 399 443 154 217 83
Other Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Components of Net Periodic Pension Costs	Components of Net Periodic Other Post-Retirement Benefit Costs Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Service cost $ 4 $ 1 $ 1 $ — $ — $ — $ 1 $ — Interest cost on accumulated post-retirement benefit obligation 23 5 10 5 4 1 2 1 Expected return on plan assets (13) (8) — — — — — (2) Amortization of actuarial loss 2 — 1 — 1 — 4 — Amortization of prior service credit (14) (4) (3) (1) (2) (1) (1) (2) Net periodic post-retirement benefit costs (a)(b) $ 2 $ (6) $ 9 $ 4 $ 3 $ — $ 6 $ (3) Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Service cost $ 4 $ 1 $ 1 $ — $ 1 $ — $ 1 $ — Interest cost on accumulated post-retirement benefit obligation 30 7 12 7 5 1 3 1 Expected return on plan assets (12) (7) — — — — — (1) Amortization of actuarial loss 4 2 1 — 1 — 4 — Amortization of prior service credit (19) (5) (8) (1) (7) (1) (1) (2) Net periodic post-retirement benefit costs (a)(b) $ 7 $ (2) $ 6 $ 6 $ — $ — $ 7 $ (2) Year Ended December 31, 2018 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Service cost $ 6 $ 1 $ 1 $ — $ 1 $ 1 $ 1 $ 1 Interest cost on accumulated post-retirement benefit obligation 28 7 12 6 6 1 3 1 Expected return on plan assets (13) (8) — — — — — (2) Amortization of actuarial loss 6 3 1 1 — — 4 — Amortization of prior service credit (19) (5) (8) (1) (7) (1) (1) (2) Net periodic post-retirement benefit costs (a)(b) $ 8 $ (2) $ 6 $ 6 $ — $ 1 $ 7 $ (2) (a) Duke Energy amounts exclude $6 million, $6 million and $7 million for the years ended December 2020, 2019 and 2018, respectively, of regulatory asset amortization resulting from purchase accounting adjustments associated with Duke Energy's merger with Cinergy in April 2006. (b) Duke Energy Ohio amounts exclude $1 million, $2 million and $2 million for the years ended December 2020, 2019 and 2018, respectively, of regulatory asset amortization resulting from purchase accounting adjustments associated with Duke Energy's merger with Cinergy in April 2006.
Amounts Recognized in AOCI and Regulatory Assets and Liabilities	Amounts Recognized in Accumulated Other Comprehensive Income and Regulatory Assets and Liabilities Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Regulatory assets, net increase (decrease) $ 9 $ — $ 9 $ 6 $ 3 $ — $ (4) $ — Regulatory liabilities, net increase (decrease) $ (10) $ (7) $ — $ — $ — $ — $ (1) $ — Accumulated other comprehensive (income) loss Deferred income tax benefit $ — $ — $ — $ — $ — $ — $ — $ — Amortization of prior year service credit 1 — — — — — — — Net amount recognized in accumulated other comprehensive income $ 1 $ — $ — $ — $ — $ — $ — $ — Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Regulatory assets, net increase (decrease) $ (127) $ — $ (127) $ (82) $ (45) $ — $ (5) $ — Regulatory liabilities, net increase (decrease) $ (152) $ 1 $ (149) $ (93) $ (56) $ (1) $ (4) $ 3 Accumulated other comprehensive (income) loss Deferred income tax benefit $ — $ — $ — $ — $ — $ — $ — $ — Amortization of prior year actuarial gain (4) — — — — — — — Net amount recognized in accumulated other comprehensive income $ (4) $ — $ — $ — $ — $ — $ — $ —
Reconciliation of Funded Status to Net Amount Recognized	Reconciliation of Funded Status to Accrued Other Post-Retirement Benefit Costs Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Change in Projected Benefit Obligation Accumulated post-retirement benefit obligation at prior measurement date $ 723 $ 175 $ 303 $ 168 $ 135 $ 29 $ 64 $ 30 Service cost 4 1 1 — — — 1 — Interest cost 23 5 10 5 4 1 2 1 Plan participants' contributions 15 3 5 3 2 1 2 — Actuarial losses 19 8 8 5 2 — 1 1 Benefits paid (75) (18) (28) (15) (13) (4) (9) (2) Accumulated post-retirement benefit obligation at measurement date $ 709 $ 174 $ 299 $ 166 $ 130 $ 27 $ 61 $ 30 Change in Fair Value of Plan Assets Plan assets at prior measurement date $ 220 $ 130 $ (1) $ (1) $ — $ 9 $ 5 $ 34 Actual return on plan assets 24 14 — — — — 1 4 Benefits paid (75) (18) (28) (15) (13) (4) (9) (2) Employer contributions 53 10 23 11 10 3 8 1 Plan participants' contributions 15 3 5 3 2 1 2 — Plan assets at measurement date $ 237 $ 139 $ (1) $ (2) $ (1) $ 9 $ 7 $ 37 Funded status of plan $ (472) $ (35) $ (300) $ (168) $ (131) $ (18) $ (54) $ 7 Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Change in Projected Benefit Obligation Accumulated post-retirement benefit obligation at prior measurement date $ 728 $ 174 $ 303 $ 166 $ 137 $ 29 $ 67 $ 30 Service cost 4 1 1 — 1 — 1 — Interest cost 30 7 12 7 5 1 3 1 Plan participants' contributions 16 3 6 3 2 1 2 — Actuarial losses 28 9 13 9 5 1 2 — Benefits paid (83) (19) (32) (17) (15) (3) (11) (1) Accumulated post-retirement benefit obligation at measurement date $ 723 $ 175 $ 303 $ 168 $ 135 $ 29 $ 64 $ 30 Change in Fair Value of Plan Assets Plan assets at prior measurement date $ 195 $ 115 $ — $ — $ — $ 8 $ 5 $ 29 Actual return on plan assets 32 20 (1) — — 1 — 6 Benefits paid (83) (19) (32) (17) (15) (3) (11) (1) Employer contributions 60 11 26 13 13 2 9 — Plan participants' contributions 16 3 6 3 2 1 2 — Plan assets at measurement date $ 220 $ 130 $ (1) $ (1) $ — $ 9 $ 5 $ 34 Funded status of plan $ (503) $ (45) $ (304) $ (169) $ (135) $ (20) $ (59) $ 4
Amounts Recognized in the Consolidated Balance Sheet	Amounts Recognized in the Consolidated Balance Sheets December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Prefunded post-retirement benefit $ 8 $ — $ — $ — $ — $ 1 $ — $ 7 Current post-retirement liability (a) 9 — 6 4 2 2 — — Noncurrent post-retirement liability (b) 471 35 294 164 129 17 54 — Net liability (asset) recognized $ 472 $ 35 $ 300 $ 168 $ 131 $ 18 $ 54 $ (7) Regulatory assets $ 144 $ — $ 144 $ 88 $ 56 $ — $ 32 $ — Regulatory liabilities $ 139 $ 32 $ — $ — $ — $ 17 $ 62 $ 3 Accumulated other comprehensive (income) loss Deferred income tax expense $ 3 $ — $ — $ — $ — $ — $ — $ — Prior service credit (1) — — — — — — — Net actuarial gain (13) — — — — — — — Net amounts recognized in accumulated other comprehensive income $ (11) $ — $ — $ — $ — $ — $ — $ — December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Current post-retirement liability (a) $ 9 $ — $ 5 $ 3 $ 2 $ 1 $ — $ — Noncurrent post-retirement liability (b) 494 45 299 163 133 19 59 (4) Total accrued post-retirement liability $ 503 $ 45 $ 304 $ 166 $ 135 $ 20 $ 59 $ (4) Regulatory assets $ 135 $ — $ 135 $ 82 $ 53 $ — $ 36 $ — Regulatory liabilities $ 149 $ 39 $ — $ — $ — $ 17 $ 63 $ 3 Accumulated other comprehensive (income) loss Deferred income tax expense $ 3 $ — $ — $ — $ — $ — $ — $ — Prior service credit (2) — — — — — — — Net actuarial gain (13) — — — — — — — Net amounts recognized in accumulated other comprehensive income $ (12) $ — $ — $ — $ — $ — $ — $ — Amounts to be recognized in net periodic pension expense in the next year Unrecognized net actuarial loss $ 5 $ 3 $ 1 $ — $ 1 $ — $ — $ — Unrecognized prior service credit (14) (4) (3) (1) (2) (1) (1) (2) (a) Included in Other within Current Liabilities on the Consolidated Balance Sheets. (b) Included in Accrued pension and other post-retirement benefit costs on the Consolidated Balance Sheets.
Assumptions Used for Pension Benefits Accounting	The following tables present the assumptions used for other post-retirement benefits accounting. December 31, 2020 2019 2018 Benefit Obligations Discount rate 2.60 % 3.30 % 4.30 % Net Periodic Benefit Cost Discount rate 3.30 % 4.30 % 3.60 % Expected long-term rate of return on plan assets 6.85 % 6.85 % 6.50 % Assumed tax rate 23 % 23 % 35 %
Assumed Health Care Cost Trend Rate	Assumed Health Care Cost Trend Rate December 31, 2020 2019 Health care cost trend rate assumed for next year 6.25 % 6.00 % Rate to which the cost trend is assumed to decline (the ultimate trend rate) 4.75 % 4.75 % Year that rate reaches ultimate trend 2028 2026
Expected Benefit Payments	Expected Benefit Payments Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Years ending December 31, 2021 $ 73 $ 17 $ 28 $ 15 $ 12 $ 3 $ 8 $ 2 2022 66 16 26 14 12 3 7 2 2023 62 15 25 14 11 3 6 2 2024 58 14 24 13 11 2 6 2 2025 54 13 22 12 10 2 5 2 2026-2030 223 54 94 52 41 9 21 11

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense (Benefit)	Components of Income Tax Expense Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Current income taxes Federal $ (281) $ 314 $ 280 $ 181 $ 148 $ 10 $ 48 $ (27) State (9) 35 29 17 24 1 7 (8) Foreign 1 — — — — — — — Total current income taxes (289) 349 309 198 172 11 55 (35) Deferred income taxes Federal 155 (171) (167) (180) 1 30 12 60 State (92) (86) (24) (49) 25 2 17 (7) Total deferred income taxes (a) 63 (257) (191) (229) 26 32 29 53 ITC amortization (10) (4) (5) (5) — — — — Income tax (benefit) expense from continuing operations (236) 88 113 (36) 198 43 84 18 Tax expense from discontinued operations 2 — — — — — — — Total income tax (benefit) expense included in Consolidated Statements of Operations $ (234) $ 88 $ 113 $ (36) $ 198 $ 43 $ 84 $ 18 (a) Total deferred income taxes includes the generation of NOL carryforwards and tax credit carryforwards of $20 million at Duke Energy Carolinas, $3 million at Duke Energy Progress, $8 million at Duke Energy Indiana, and $11 million at Piedmont. In addition, total deferred income taxes includes utilization of NOL carryforwards and tax credit carryforwards of $39 million at Progress Energy, $30 million at Duke Energy Florida and $79 million at Duke Energy. Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Current income taxes Federal $ (299) $ 164 $ (173) $ (36) $ (43) $ (41) $ (23) $ (92) State 10 13 (7) (3) 18 (1) 1 (1) Foreign 2 — — — — — — — Total current income taxes (287) 177 (180) (39) (25) (42) (22) (93) Deferred income taxes Federal 855 175 422 220 153 77 128 133 State (38) (37) 17 (18) 27 5 28 3 Total deferred income taxes (a) 817 138 439 202 180 82 156 136 ITC amortization (11) (4) (6) (6) — — — — Income tax expense from continuing operations 519 311 253 157 155 40 134 43 Tax benefit from discontinued operations (2) — — — — — — — Total income tax expense included in Consolidated Statements of Operations $ 517 $ 311 $ 253 $ 157 $ 155 $ 40 $ 134 $ 43 (a) Total deferred income taxes includes the generation of tax credit carryforwards of $8 million at Duke Energy Carolinas. In addition, total deferred income taxes includes utilization of NOL carryforwards and tax credit carryforwards of $243 million at Progress Energy, $35 million at Duke Energy Progress, $152 million at Duke Energy Florida, $25 million at Duke Energy Ohio, $60 million at Duke Energy Indiana, $90 million at Piedmont and $775 million at Duke Energy. Year Ended December 31, 2018 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Current income taxes Federal $ (647) $ (8) $ (135) $ (71) $ (49) $ 20 $ 29 $ 67 State (11) 6 (5) (5) (10) (1) 3 1 Foreign 3 — — — — — — — Total current income taxes (655) (2) (140) (76) (59) 19 32 68 Deferred income taxes Federal 1,064 299 341 256 115 21 74 (36) State 49 11 20 (17) 45 3 22 5 Total deferred income taxes (a)(b) 1,113 310 361 239 160 24 96 (31) ITC amortization (10) (5) (3) (3) — — — — Income tax expense from continuing operations 448 303 218 160 101 43 128 37 Tax benefit from discontinued operations (26) — — — — — — — Total income tax expense included in Consolidated Statements of Operations $ 422 $ 303 $ 218 $ 160 $ 101 $ 43 $ 128 $ 37 (a) Includes benefits of NOL carryforwards and tax credit carryforwards of $22 million at Duke Energy Carolinas, $293 million at Progress Energy, $59 million at Duke Energy Progress, $219 million at Duke Energy Florida, $17 million at Duke Energy Ohio, $21 million at Duke Energy Indiana and $39 million at Piedmont. In addition, total deferred income taxes includes utilization of NOL carryforwards and tax credit carryforwards of $18 million at Duke Energy. (b) For the year ended December 31, 2018, the Company has revised the December 31, 2017, estimates of the income tax effects of the Tax Act, in accordance with SAB 118. See the Statutory Rate Reconciliation section below for additional information on the Tax Act's impact on income tax expense .
Schedule of Income before Income Tax, Domestic and Foreign	Duke Energy Income from Continuing Operations before Income Taxes Years Ended December 31, (in millions) 2020 2019 2018 Domestic $ 826 $ 4,053 $ 3,018 Foreign 13 44 55 Income from continuing operations before income taxes $ 839 $ 4,097 $ 3,073
Summary of Effective Tax Rates	The following tables present a reconciliation of income tax expense at the U.S. federal statutory tax rate to the actual tax expense from continuing operations. Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Income tax expense, computed at the statutory rate of 21% $ 176 $ 219 $ 243 $ 80 $ 204 $ 62 $ 103 $ 61 State income tax, net of federal income tax effect (80) (40) 4 (25) 39 2 19 (12) Amortization of excess deferred income tax (276) (82) (118) (68) (49) (20) (36) (21) AFUDC equity income (48) (13) (9) (6) (3) (2) (4) (10) AFUDC equity depreciation 103 19 10 5 5 1 4 — Noncontrolling Interests 62 — — — — — — — Renewable energy PTCs (110) — — — — — — — Other tax credits (37) (13) (16) (14) (2) (1) (3) (2) Tax true up (12) (3) 1 (5) 5 — (1) 1 Other items, net (14) 1 (2) (3) (1) 1 2 1 Income tax (benefit) expense from continuing operations $ (236) $ 88 $ 113 $ (36) $ 198 $ 43 $ 84 $ 18 Effective tax rate (28.1) % 8.4 % 9.7 % (9.5) % 20.4 % 14.6 % 17.1 % 6.2 % Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Income tax expense, computed at the statutory rate of 21% $ 860 $ 360 $ 332 $ 202 $ 178 $ 59 $ 120 $ 51 State income tax, net of federal income tax effect (22) (19) 8 (17) 35 3 22 2 Amortization of excess deferred income tax (121) (29) (64) (10) (54) (12) (6) (10) AFUDC equity income (52) (9) (14) (13) (1) (3) (3) — AFUDC equity depreciation 34 19 10 5 5 1 4 — Renewable energy PTCs (120) — — — — — — — Other tax credits (23) (11) (9) (7) (2) (1) (1) (1) Tax true up (64) (9) (8) (3) (5) (7) (1) — Other items, net 27 9 (2) — (1) — (1) 1 Income tax expense from continuing operations $ 519 $ 311 $ 253 $ 157 $ 155 $ 40 $ 134 $ 43 Effective tax rate 12.7 % 18.1 % 16.0 % 16.3 % 18.3 % 14.3 % 23.5 % 17.6 % Year Ended December 31, 2018 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Income tax expense, computed at the statutory rate of 21% $ 645 $ 288 $ 263 $ 174 $ 137 $ 46 $ 109 $ 35 State income tax, net of federal income tax effect 30 14 13 (17) 28 2 20 4 Amortization of excess deferred income tax (61) — (55) (1) (54) (3) (2) — AFUDC equity income (42) (15) (22) (12) (10) (2) (2) — AFUDC equity depreciation 31 18 9 5 4 1 4 — Renewable energy PTCs (129) — — — — — — — Other tax credits (28) (7) (13) (5) (8) (1) (1) (3) Tax Act (a) 20 1 25 19 — 2 — — Other items, net (18) 4 (2) (3) 4 (2) — 1 Income tax expense from continuing operations $ 448 $ 303 $ 218 $ 160 $ 101 $ 43 $ 128 $ 37 Effective tax rate 14.6 % 22.1 % 17.4 % 19.3 % 15.4 % 19.6 % 24.6 % 22.3 % (a) For the year ended December 31, 2018, the Company revised the December 31, 2017, estimates of the income tax effects of the Tax Act, in accordance with SAB 118. Amounts primarily include but are not limited to items that are excluded for ratemaking purposes related certain wholesale fixed-rate contracts, remeasurement of nonregulated net deferred tax liabilities, Federal NOLs, and valuation allowance on foreign tax credits.
Schedule of Deferred Tax Assets and Liabilities	Net Deferred Income Tax Liability Components December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Deferred credits and other liabilities $ 286 $ 85 $ 87 $ 67 $ 18 $ 21 $ 7 $ 38 Lease obligations 515 96 208 120 87 5 16 5 Pension, post-retirement and other employee benefits 236 (30) 68 24 38 16 26 (5) Progress Energy merger purchase accounting adjustments (a) 441 — — — — — — — Tax credits and NOL carryforwards 3,909 285 508 179 282 16 183 29 Regulatory liabilities and deferred credits — 11 — — — 18 — — Investments and other assets — — — — — 7 — Other 93 8 14 9 4 7 1 8 Valuation allowance (586) — — — — — — — Total deferred income tax assets 4,894 455 885 399 429 90 233 75 Investments and other assets (2,267) (1,127) (669) (507) (164) — (14) (48) Accelerated depreciation rates (10,729) (3,170) (3,868) (1,778) (2,124) (1,071) (1,433) (844) Regulatory assets and deferred debits, net (1,142) — (744) (412) (332) — (14) (4) Total deferred income tax liabilities (14,138) (4,297) (5,281) (2,697) (2,620) (1,071) (1,461) (896) Net deferred income tax liabilities $ (9,244) $ (3,842) $ (4,396) $ (2,298) $ (2,191) $ (981) $ (1,228) $ (821) (a) Primarily related to lease obligations and debt fair value adjustments. December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Deferred credits and other liabilities $ 125 $ 24 $ 25 $ 49 $ — $ 14 $ 5 $ 22 Lease obligations 462 72 193 92 102 5 17 6 Pension, post-retirement and other employee benefits 303 (5) 88 38 44 17 27 (3) Progress Energy merger purchase accounting adjustments (a) 389 — — — — — — — Tax credits and NOL carryforwards 3,925 262 486 176 253 16 176 19 Regulatory liabilities and deferred credits — — — — — 36 52 42 Investments and other assets — — — — — 10 — 2 Other 97 5 8 3 2 8 1 6 Valuation allowance (587) — — — — — — — Total deferred income tax assets 4,714 358 800 358 401 106 278 94 Investments and other assets (1,664) (981) (577) (390) (190) — (12) — Accelerated depreciation rates (10,813) (3,254) (3,798) (1,918) (1,913) (1,028) (1,416) (802) Regulatory assets and deferred debits, net (1,115) (44) (887) (438) (477) — — — Total deferred income tax liabilities (13,592) (4,279) (5,262) (2,746) (2,580) (1,028) (1,428) (802) Net deferred income tax liabilities $ (8,878) $ (3,921) $ (4,462) $ (2,388) $ (2,179) $ (922) $ (1,150) $ (708) (a) Primarily related to finance lease obligations and debt fair value adjustments.
Summary of Tax Credit Carryforwards	The following table presents the expiration of tax credits and NOL carryforwards. December 31, 2020 (in millions) Amount Expiration Year General Business Credits $ 2,033 2024 — 2040 Federal NOL carryforwards (a) (f) 154 2024 — Indefinite Capital loss carryforward (e) 85 2024 State carryforwards and credits (b) (f) 340 2021 — Indefinite Foreign NOL carryforwards (c) 12 2027 — 2037 Foreign Tax Credits (d) 1,272 2024 — 2027 Charitable contribution carryforwards 13 2025 Total tax credits and NOL carryforwards $ 3,909 (a) A valuation allowance of $4 million has been recorded on the Federal NOL carryforwards, as presented in the Net Deferred Income Tax Liability Components table. (b) A valuation allowance of $97 million has been recorded on the state NOL and attribute carryforwards, as presented in the Net Deferred Income Tax Liability Components table. (c) A valuation allowance of $12 million has been recorded on the foreign NOL carryforwards, as presented in the Net Deferred Income Tax Liability Components table. (d) A valuation allowance of $388 million has been recorded on the foreign tax credits, as presented in the Net Deferred Income Tax Liability Components table. (e) A valuation allowance of $85 million has been recorded on the Federal capital loss carryforward, as presented in the Net Deferred Income Tax Liability Components table. (f) Indefinite carryforward for Federal NOLs, and NOLs for states that have adopted the Tax Act's NOL provisions, generated in tax years beginning after December 31, 2017.
Schedule of Unrecognized Tax Benefits Roll Forward	The following tables present changes to unrecognized tax benefits. Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Unrecognized tax benefits – January 1 $ 126 $ 8 $ 9 $ 6 $ 3 $ 1 $ 1 $ 4 Gross decreases – tax positions in prior periods (2) — — — — — — — Gross increases – current period tax positions 4 2 1 — — — — — Reduction due to lapse of statute of limitations (3) — — — — — — (3) Total changes (1) 2 1 — — — — (3) Unrecognized tax benefits – December 31 $ 125 $ 10 $ 10 $ 6 $ 3 $ 1 $ 1 $ 1 Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Unrecognized tax benefits – January 1 $ 24 $ 6 $ 9 $ 6 $ 3 $ 1 $ 1 $ 4 Unrecognized tax benefits increases 105 2 1 1 — — — — Gross decreases – tax positions in prior periods (3) — (1) (1) — — — — Total changes 102 2 — — — — — — Unrecognized tax benefits – December 31 $ 126 $ 8 $ 9 $ 6 $ 3 $ 1 $ 1 $ 4 Year Ended December 31, 2018 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Unrecognized tax benefits – January 1 $ 25 $ 5 $ 5 $ 5 $ 5 $ 1 $ 1 $ 3 Unrecognized tax benefits increases (decreases) Gross decreases – tax positions in prior periods (2) (1) — — (4) — — — Gross increases – tax positions in prior periods 7 2 4 1 2 — — 1 Decreases due to settlements (6) — — — — — — — Total changes (1) 1 4 1 (2) — — 1 Unrecognized tax benefits – December 31 $ 24 $ 6 $ 9 $ 6 $ 3 $ 1 $ 1 $ 4
Summary of Income Tax Contingencies	The following table includes additional information regarding the Duke Energy Registrants' unrecognized tax benefits at December 31, 2020. Duke Energy Registrants do not anticipate a material increase or decrease in unrecognized tax benefits within the next 12 months. December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Amount that if recognized, would affect the effective tax rate or regulatory liability (a) $ 122 $ 10 $ 10 $ 6 $ 3 $ 1 $ 1 $ 1 (a) The Duke Energy Registrants are unable to estimate the specific amounts that would affect the ETR versus the regulatory liability.

Other Income and Expenses, Net

Other Income and Expenses, Net (Tables)	12 Months Ended
	Dec. 31, 2020
Other Income and Expenses [Abstract]
Schedule of Other Income and Expenses, Net	The components of Other income and expenses, net on the Consolidated Statements of Operations are as follows. Year Ended December 31, 2020 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Interest income $ 32 $ 4 $ 8 $ 2 $ 6 $ 4 $ 6 $ 17 AFUDC equity 154 62 42 29 12 7 23 19 Post in-service equity returns 27 17 8 8 — 1 1 — Nonoperating income, other 240 94 71 36 35 4 7 15 Other income and expense, net $ 453 $ 177 $ 129 $ 75 $ 53 $ 16 $ 37 $ 51 Year Ended December 31, 2019 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Interest income $ 31 $ 1 $ 11 $ — $ 11 $ 10 $ 10 $ 1 AFUDC equity 139 42 66 60 6 13 18 — Post in-service equity returns 29 20 7 7 — 1 — — Nonoperating income, other 231 88 57 33 31 — 13 19 Other income and expense, net $ 430 $ 151 $ 141 $ 100 $ 48 $ 24 $ 41 $ 20 Year Ended December 31, 2018 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Interest income $ 20 $ 1 $ 18 $ 1 $ 18 $ 7 $ 9 $ 1 AFUDC equity 221 73 104 57 47 11 32 — Post in-service equity returns 15 9 5 5 — 1 — — Nonoperating income, other 143 70 38 24 21 4 4 13 Other income and expense, net $ 399 $ 153 $ 165 $ 87 $ 86 $ 23 $ 45 $ 14

Summary of Significant Accoun_4

Summary of Significant Accounting Policies (COVID 19) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Noncontrolling Interest [Line Items]
Operation, maintenance and other	$ 5,788	$ 6,066	$ 6,463
Incremental COVID-19 costs
Noncontrolling Interest [Line Items]
Operation, maintenance and other	112
Waived late payment fees	64
Deferred costs	$ 76

Summary of Significant Accoun_5

Summary of Significant Accounting Policies (Other Assets and Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Current Liabilities
Organization And Basis Of Presentation [Line Items]
Other accrued liabilities	$ 1,455	$ 604
Accrued compensation	662	862
Duke Energy Carolinas | Current Liabilities
Organization And Basis Of Presentation [Line Items]
Other accrued liabilities	178	147
Accrued compensation	213	271
Progress Energy | Current Liabilities
Organization And Basis Of Presentation [Line Items]
Customer deposits	347	354
Duke Energy Florida | Current Liabilities
Organization And Basis Of Presentation [Line Items]
Customer deposits	203	209
Duke Energy Ohio | Current Assets
Organization And Basis Of Presentation [Line Items]
Gas Storage	21	0
Duke Energy Indiana | Current Assets
Organization And Basis Of Presentation [Line Items]
Income taxes receivable	$ 9	$ 44

Summary of Significant Accoun_6

Summary of Significant Accounting Policies (Noncontrolling Interest) (Details) - Noncontrolling Interests $ in Millions	1 Months Ended	3 Months Ended
	Jan. 31, 2021USD ($)	Sep. 30, 2019USD ($)asset	Jan. 31, 2023	Jun. 30, 2021
Duke Energy Indiana [Member] | Subsequent Event
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Value of sale of parent interest	$ 2,000
Percentage sold	19.90%
Holding company ownership of interest	100.00%
Ownership interest sold			19.90%	11.10%
Proceed of purchase price for exchange in interest			50.00%	50.00%
Renewables
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Value of sale of parent interest		$ 415
Ownership interest change		466
Tax benefit from sale of interest		$ 8
Wind and Solar Storage
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Percentage sold		49.00%
Number of assets sold | asset		37
Operating Solar Assets
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Percentage sold		33.00%
Number of assets sold | asset		11

Summary of Significant Accoun_7

Summary of Significant Accounting Policies (Schedule of Cash Received and Allocated Losses from Subsidiaries, Noncontrolling Interest) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash received for the sale of noncontrolling interest to tax equity members	$ 426	$ 428
Cash received for the sale of noncontrolling interest to pro rata share members		415
Total Noncontrolling Interest Capital Contributions	426	843	$ 41
Allocated losses to noncontrolling tax equity members utilizing the HLBV method	271	165
Allocated losses to noncontrolling members based on pro rata shares of ownership	24	12
Total Noncontrolling Interest Allocated Losses	$ 295	$ 177

Summary of Significant Accoun_8

Summary of Significant Accounting Policies (Schedule of Cash and Cash Equivalents) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current Assets
Cash and cash equivalents	$ 259	$ 311
Other	194	222
Other Noncurrent Assets
Other	103	40
Total cash, cash equivalents and restricted cash	556	573	$ 591	$ 505
Progress Energy
Current Assets
Cash and cash equivalents	59	48
Other	39	39
Other Noncurrent Assets
Other	102	39
Total cash, cash equivalents and restricted cash	200	126	112	87
Duke Energy Florida
Current Assets
Cash and cash equivalents	11	17
Other	39	39
Other Noncurrent Assets
Total cash, cash equivalents and restricted cash	$ 50	$ 56	$ 75	$ 53

Summary of Significant Accoun_9

Summary of Significant Accounting Policies (Inventory) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Public Utilities, Inventory [Line Items]
Materials and supplies	$ 2,312	$ 2,297
Coal	561	586
Natural gas, oil, other	294	349
Total inventory	3,167	3,232
Duke Energy Carolinas
Public Utilities, Inventory [Line Items]
Materials and supplies	785	768
Coal	186	187
Natural gas, oil, other	39	41
Total inventory	1,010	996
Progress Energy
Public Utilities, Inventory [Line Items]
Materials and supplies	999	1,038
Coal	193	186
Natural gas, oil, other	183	199
Total inventory	1,375	1,423
Duke Energy Progress
Public Utilities, Inventory [Line Items]
Materials and supplies	673	686
Coal	131	138
Natural gas, oil, other	107	110
Total inventory	911	934
Duke Energy Florida
Public Utilities, Inventory [Line Items]
Materials and supplies	325	351
Coal	63	48
Natural gas, oil, other	76	90
Total inventory	464	489
Duke Energy Ohio
Public Utilities, Inventory [Line Items]
Materials and supplies	78	79
Coal	16	15
Natural gas, oil, other	16	41
Total inventory	110	135
Duke Energy Indiana
Public Utilities, Inventory [Line Items]
Materials and supplies	307	318
Coal	165	198
Natural gas, oil, other	1	1
Total inventory	473	517
Piedmont
Public Utilities, Inventory [Line Items]
Materials and supplies	12	5
Natural gas, oil, other	56	67
Total inventory	$ 68	$ 72

Summary of Significant Accou_10

Summary of Significant Accounting Policies (Property, Plant and Equipment) (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Public Utility, Property, Plant and Equipment [Line Items]
Weighted-average depreciation rate	3.00%	3.10%	3.00%
Duke Energy Carolinas
Public Utility, Property, Plant and Equipment [Line Items]
Weighted-average depreciation rate	2.80%	2.80%	2.80%
Progress Energy
Public Utility, Property, Plant and Equipment [Line Items]
Weighted-average depreciation rate	3.20%	3.10%	2.90%
Duke Energy Progress
Public Utility, Property, Plant and Equipment [Line Items]
Weighted-average depreciation rate	3.10%	3.10%	2.90%
Duke Energy Florida
Public Utility, Property, Plant and Equipment [Line Items]
Weighted-average depreciation rate	3.30%	3.10%	3.00%
Duke Energy Ohio
Public Utility, Property, Plant and Equipment [Line Items]
Weighted-average depreciation rate	2.90%	2.60%	2.80%
Duke Energy Indiana
Public Utility, Property, Plant and Equipment [Line Items]
Weighted-average depreciation rate	3.50%	3.30%	3.30%
Piedmont
Public Utility, Property, Plant and Equipment [Line Items]
Weighted-average depreciation rate	2.30%	2.40%	2.50%

Summary of Significant Accou_11

Summary of Significant Accounting Policies (Payables) (Details) $ in Millions	Dec. 31, 2020USD ($)
Payables [Line Items]
Payables sold by suppliers	$ 15
Cumulative payables sold by suppliers	45
Duke Energy Ohio
Payables [Line Items]
Payables sold by suppliers	1
Cumulative payables sold by suppliers	9
Piedmont
Payables [Line Items]
Payables sold by suppliers	14
Cumulative payables sold by suppliers	$ 36

Summary of Significant Accou_12

Summary of Significant Accounting Policies (Excise Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Organization And Basis Of Presentation [Line Items]
Excise taxes	$ 415	$ 421	$ 405
Duke Energy Carolinas
Organization And Basis Of Presentation [Line Items]
Excise taxes	43	39	35
Progress Energy
Organization And Basis Of Presentation [Line Items]
Excise taxes	249	256	241
Duke Energy Progress
Organization And Basis Of Presentation [Line Items]
Excise taxes	26	21	19
Duke Energy Florida
Organization And Basis Of Presentation [Line Items]
Excise taxes	223	235	222
Duke Energy Ohio
Organization And Basis Of Presentation [Line Items]
Excise taxes	96	101	105
Duke Energy Indiana
Organization And Basis Of Presentation [Line Items]
Excise taxes	25	23	22
Piedmont
Organization And Basis Of Presentation [Line Items]
Excise taxes	$ 2	$ 2	$ 2

Summary of Significant Accou_13

Summary of Significant Accounting Policies (Expected Reserve for Credit Losses) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	$ 49,184	$ 47,951	$ 43,834	$ 41,737
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	2,471	4,108	3,113	3,013
Cumulative Effect, Period of Adoption, Adjustment | Revision of Prior Period, Accounting Standards Update, Adjustment | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	120
Duke Energy Carolinas | Cumulative Effect, Period of Adoption, Adjustment | Revision of Prior Period, Accounting Standards Update, Adjustment | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	16
Progress Energy
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	16,241	15,593	14,257	13,465
Progress Energy | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	7,109	$ 6,465	$ 5,131	$ 4,350
Progress Energy | Cumulative Effect, Period of Adoption, Adjustment | Revision of Prior Period, Accounting Standards Update, Adjustment | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	2
Duke Energy Progress | Cumulative Effect, Period of Adoption, Adjustment | Revision of Prior Period, Accounting Standards Update, Adjustment | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	1
Duke Energy Florida | Cumulative Effect, Period of Adoption, Adjustment | Revision of Prior Period, Accounting Standards Update, Adjustment | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	1
Piedmont | Cumulative Effect, Period of Adoption, Adjustment | Revision of Prior Period, Accounting Standards Update, Adjustment | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	$ 1

Business Segments (Business Seg

Business Segments (Business Segment Data) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	$ 23,868	$ 25,079	$ 24,521
Interest expense	2,162	2,204	2,094
Depreciation and amortization	4,705	4,548	4,074
Equity in (losses) earnings of unconsolidated affiliates	(2,005)	162	83
Income tax expense (benefit) from continuing operations	(236)	519	448
Segment income (loss)	1,263	3,714	2,647
Add back noncontrolling interests component	295	177	22
Add back preferred stock dividend	107	41
Loss from discontinued operations, net of tax	7	(7)	19
Net income (loss)	1,377	3,748	2,666
Capital expenditures	10,421	11,446	9,668
Segment assets	162,388	158,838	145,392
Segment Reporting Information Assets [Abstract]
After-tax severance charges	(85)	16	187
Duke Energy Ohio
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	1,858	1,940	1,957
Interest expense	102	109	92
Depreciation and amortization	278	265	268
Income tax expense (benefit) from continuing operations	43	40	43
Segment income (loss)	252	239	176
Loss from discontinued operations, net of tax		(1)
Net income (loss)	252	238	176
Capital expenditures	834	952	827
Segment assets	10,025	9,338	8,555
Segment Reporting Information Assets [Abstract]
After-tax severance charges			6
Eliminations
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	(199)	(200)	(199)
Interest expense	(16)	(58)	(45)
Depreciation and amortization	(29)	(5)	(1)
Segment assets		188	188
Eliminations | Duke Energy Ohio
Segment Reporting Information, Profit (Loss) [Abstract]
Segment assets	(2)
Electric Utilities and Infrastructure
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	21,687	22,798	22,242
Equity in (losses) earnings of unconsolidated affiliates	(1)	9	6
Segment Reporting Information Assets [Abstract]
After tax impairment charge	948
Reduction of prior year impairment	152
Tax Act				$ 24
Shareholder Contribution expense	16
Electric Utilities and Infrastructure | After-tax impairment charge
Segment Reporting Information Assets [Abstract]
After tax impairment charge			46
Electric Utilities and Infrastructure | Regulatory settlements
Segment Reporting Information Assets [Abstract]
Regulatory settlement charges			202
Electric Utilities and Infrastructure | Clemson University Combined Heat and Power Plant
Segment Reporting Information Assets [Abstract]
After tax impairment charge	19
Electric Utilities and Infrastructure | Gas Pipeline Assets
Segment Reporting Information Assets [Abstract]
After tax impairment charge	5
Electric Utilities and Infrastructure | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	21,720	22,831	22,273
Interest expense	1,320	1,345	1,288
Depreciation and amortization	4,068	3,951	3,523
Equity in (losses) earnings of unconsolidated affiliates	(1)	9	5
Income tax expense (benefit) from continuing operations	340	785	799
Segment income (loss)	2,669	3,536	3,058
Capital expenditures	7,629	8,263	8,086
Segment assets	138,225	135,561	125,364
Segment Reporting Information Assets [Abstract]
Reduction of prior year impairment		27
Electric Utilities and Infrastructure | Operating Segments | Duke Energy Ohio
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	1,405	1,456	1,450
Interest expense	85	80	67
Depreciation and amortization	200	182	183
Income tax expense (benefit) from continuing operations	19	20	47
Segment income (loss)	162	159	186
Capital expenditures	548	680	655
Segment assets	6,615	6,188	5,643
Electric Utilities and Infrastructure | Eliminations
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	33	33	31
Gas Utilities and Infrastructure
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	1,653	1,770	1,783
Equity in (losses) earnings of unconsolidated affiliates	(2,017)	114	27
Segment Reporting Information Assets [Abstract]
After tax impairment charge	7
Tax Act				1
Gas Utilities and Infrastructure | After-tax impairment charge
Segment Reporting Information, Profit (Loss) [Abstract]
Equity in (losses) earnings of unconsolidated affiliates	2,100
Segment Reporting Information Assets [Abstract]
After tax impairment charge		19	42
Gas Utilities and Infrastructure | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	1,748	1,866	1,881
Interest expense	135	117	106
Depreciation and amortization	258	256	245
Equity in (losses) earnings of unconsolidated affiliates	(2,017)	114	27
Income tax expense (benefit) from continuing operations	(349)	22	78
Segment income (loss)	(1,266)	432	274
Capital expenditures	1,309	1,539	1,133
Segment assets	13,849	13,921	12,361
Gas Utilities and Infrastructure | Operating Segments | Duke Energy Ohio
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	453	484	506
Interest expense	17	29	24
Depreciation and amortization	78	83	85
Income tax expense (benefit) from continuing operations	26	21	24
Segment income (loss)	96	85	93
Capital expenditures	286	272	172
Segment assets	3,380	3,116	2,874
Gas Utilities and Infrastructure | Eliminations
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	95	96	98
Commercial Renewables
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	502	487	477
Equity in (losses) earnings of unconsolidated affiliates		(4)	(1)
Segment Reporting Information Assets [Abstract]
Tax Act				3
Commercial Renewables | Noncontrolling Interests
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues			91
Segment Reporting Information Assets [Abstract]
After tax impairment charge			2
Commercial Renewables | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	502	487	477
Interest expense	66	95	88
Depreciation and amortization	199	168	155
Equity in (losses) earnings of unconsolidated affiliates		(4)	(1)
Income tax expense (benefit) from continuing operations	(65)	(115)	(147)
Segment income (loss)	286	198	9
Capital expenditures	1,219	1,423	193
Segment assets	6,716	6,020	4,204
Total Reportable Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	23,842	25,055	24,502
Total Reportable Segments | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	23,970	25,184	24,631
Interest expense	1,521	1,557	1,482
Depreciation and amortization	4,525	4,375	3,923
Equity in (losses) earnings of unconsolidated affiliates	(2,018)	119	31
Income tax expense (benefit) from continuing operations	(74)	692	730
Segment income (loss)	1,689	4,166	3,341
Capital expenditures	10,157	11,225	9,412
Segment assets	158,790	155,502	141,929
Total Reportable Segments | Operating Segments | Duke Energy Ohio
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	1,858	1,940	1,956
Interest expense	102	109	91
Depreciation and amortization	278	265	268
Income tax expense (benefit) from continuing operations	45	41	71
Segment income (loss)	258	244	279
Capital expenditures	834	952	827
Segment assets	9,995	9,304	8,517
Total Reportable Segments | Eliminations
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	128	129	129
Other
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	26	24	19
Segment Reporting Information Assets [Abstract]
Tax Act				$ 2
Costs to achieve mergers, acquisition costs			65
Other | Other
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	97	95	89
Interest expense	657	705	657
Depreciation and amortization	209	178	152
Equity in (losses) earnings of unconsolidated affiliates	13	43	52
Income tax expense (benefit) from continuing operations	(162)	(173)	(282)
Segment income (loss)	(426)	(452)	(694)
Capital expenditures	264	221	256
Segment assets	3,598	3,148	3,275
Other | Other | Duke Energy Ohio
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues			1
Interest expense			1
Income tax expense (benefit) from continuing operations	(2)	(1)	(28)
Segment income (loss)	(6)	(5)	(103)
Segment assets	32	34	38
Other | Eliminations
Segment Reporting Information, Profit (Loss) [Abstract]
Revenues	71	71	70
Other
Segment Reporting Information, Profit (Loss) [Abstract]
Equity in (losses) earnings of unconsolidated affiliates	13	$ 43	51
Segment Reporting Information Assets [Abstract]
After-tax severance charges			144
Loss in disposal			$ 82
Severance Charge Reversal	$ 98

Business Segments (Narrative) (

Business Segments (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)segment	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Segment Reporting Information [Line Items]
Loss on sale	$ (10)	$ 4	$ 89
Operation, maintenance and other	5,788	6,066	6,463
Revenues	23,868	25,079	24,521
Duke Energy Progress
Segment Reporting Information [Line Items]
Loss on sale	(8)		(9)
Operation, maintenance and other	1,332	1,446	1,578
Revenues	$ 5,422	5,957	5,699
Number of reportable segments | segment	1
Duke Energy Ohio
Segment Reporting Information [Line Items]
Loss on sale			106
Operation, maintenance and other	$ 463	520	480
Revenues	$ 1,858	$ 1,940	1,957
Number of reportable segments | segment	2
Revenues | Duke Energy Progress | Customer Concentration | One customer
Segment Reporting Information [Line Items]
Revenues	$ 553
Beckjord
Segment Reporting Information [Line Items]
Loss on sale			106
Operation, maintenance and other			$ 1

Business Segments (Schedule of

Business Segments (Schedule of Revenue, By Products and Services) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Revenues	$ 23,868	$ 25,079	$ 24,521
Electric Utilities and Infrastructure
Segment Reporting Information [Line Items]
Revenues	21,687	22,798	22,242
Gas Utilities and Infrastructure
Segment Reporting Information [Line Items]
Revenues	1,653	1,770	1,783
Commercial Renewables
Segment Reporting Information [Line Items]
Revenues	502	487	477
Total Reportable Segments
Segment Reporting Information [Line Items]
Revenues	23,842	25,055	24,502
Retail Electric
Segment Reporting Information [Line Items]
Revenues	18,898	19,745	19,013
Retail Electric | Electric Utilities and Infrastructure
Segment Reporting Information [Line Items]
Revenues	18,898	19,745	19,013
Wholesale Electric
Segment Reporting Information [Line Items]
Revenues	2,312	2,620	2,720
Wholesale Electric | Electric Utilities and Infrastructure
Segment Reporting Information [Line Items]
Revenues	1,878	2,231	2,345
Wholesale Electric | Commercial Renewables
Segment Reporting Information [Line Items]
Revenues	434	389	375
Retail Natural Gas
Segment Reporting Information [Line Items]
Revenues	1,691	1,782	1,817
Retail Natural Gas | Gas Utilities and Infrastructure
Segment Reporting Information [Line Items]
Revenues	1,691	1,782	1,817
Other
Segment Reporting Information [Line Items]
Revenues	1,069	1,037	1,081
Other | Electric Utilities and Infrastructure
Segment Reporting Information [Line Items]
Revenues	944	855	915
Other | Gas Utilities and Infrastructure
Segment Reporting Information [Line Items]
Revenues	57	84	64
Other | Commercial Renewables
Segment Reporting Information [Line Items]
Revenues	68	98	102
Operating Segments | Electric Utilities and Infrastructure
Segment Reporting Information [Line Items]
Revenues	21,720	22,831	22,273
Operating Segments | Gas Utilities and Infrastructure
Segment Reporting Information [Line Items]
Revenues	1,748	1,866	1,881
Operating Segments | Commercial Renewables
Segment Reporting Information [Line Items]
Revenues	502	487	477
Operating Segments | Total Reportable Segments
Segment Reporting Information [Line Items]
Revenues	$ 23,970	$ 25,184	$ 24,631

Regulatory Matters (Schedule of

Regulatory Matters (Schedule of Regulatory Assets and Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	$ 14,062	$ 15,018
Less: current portion	1,641	1,796
Total noncurrent regulatory assets	12,421	13,222
Total regulatory liabilities	16,406	16,048
Less: current portion	1,377	784
Total noncurrent regulatory liabilities	15,029	15,264
Net regulatory liability related to income taxes
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	7,368	7,872
Costs of removal
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	5,883	5,756
AROs – nuclear and other
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	1,512	1,100
Provision for rate refunds
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	344	370
Accrued pension and OPEB
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	177	176
Amounts to be refunded to customers
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	51	34
Deferred fuel and purchased power
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	18	1
Other
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	1,053	739
AROs – coal ash
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	3,408	4,084
AROs – nuclear and other
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	754	739
Accrued pension and OPEB
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	2,317	2,391
Storm cost deferrals
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	1,102	1,399
Nuclear asset securitized balance, net
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	991	1,042
Debt fair value adjustment
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	950	1,019
Retired generation facilities
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	417	331
Post-in-service carrying costs (PISCC) and deferred operating expenses
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	402	329
Deferred asset – Lee and Harris COLA
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	356	388
Hedge costs deferrals
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	351	356
Advanced metering infrastructure (AMI)
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	311	338
Demand side management (DSM)/Energy Efficiency (EE)
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	288	343
Vacation accrual
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	221	214
Deferred fuel and purchased power
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	213	528
COR settlement
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	128	133
NCEMPA deferrals
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	124	72
Nuclear deferral
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	123	107
Derivatives – natural gas supply contracts
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	122	117
CEP deferral
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	117	76
Amounts due from customers
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	110	36
Qualifying facility contract buyouts
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	107	121
Customer connect project
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	105	65
Manufactured gas plant (MGP)
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	104	102
ABSAT, coal ash basin closure
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	98	65
Deferred pipeline integrity costs
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	92	79
Deferred severance charges
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	86
Incremental COVID-19 expenses
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	76
Other
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	589	544
Progress Energy
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	6,533	7,292
Less: current portion	758	946
Total noncurrent regulatory assets	5,775	6,346
Total regulatory liabilities	5,691	5,555
Less: current portion	640	330
Total noncurrent regulatory liabilities	5,051	5,225
Progress Energy | Net regulatory liability related to income taxes
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	2,411	2,595
Progress Energy | Costs of removal
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	2,666	2,561
Progress Energy | Provision for rate refunds
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	123	123
Progress Energy | Deferred fuel and purchased power
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities		1
Progress Energy | Other
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	491	275
Progress Energy | AROs – coal ash
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	1,357	1,843
Progress Energy | AROs – nuclear and other
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	685	668
Progress Energy | Accrued pension and OPEB
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	875	897
Progress Energy | Storm cost deferrals
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	893	1,214
Progress Energy | Nuclear asset securitized balance, net
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	991	1,042
Progress Energy | Retired generation facilities
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	363	266
Progress Energy | Post-in-service carrying costs (PISCC) and deferred operating expenses
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	51	33
Progress Energy | Deferred asset – Lee and Harris COLA
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	32	38
Progress Energy | Hedge costs deferrals
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	148	129
Progress Energy | Advanced metering infrastructure (AMI)
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	102	114
Progress Energy | Demand side management (DSM)/Energy Efficiency (EE)
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	241	241
Progress Energy | Vacation accrual
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	42	41
Progress Energy | Deferred fuel and purchased power
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	162	305
Progress Energy | COR settlement
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	33	35
Progress Energy | NCEMPA deferrals
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	124	72
Progress Energy | Nuclear deferral
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	35	40
Progress Energy | Qualifying facility contract buyouts
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	107	121
Progress Energy | Customer connect project
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	55	37
Progress Energy | ABSAT, coal ash basin closure
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	27	15
Progress Energy | Deferred severance charges
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	29
Progress Energy | Incremental COVID-19 expenses
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	23
Progress Energy | Other
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	158	141
Duke Energy Carolinas
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	3,469	3,910
Less: current portion	473	550
Total noncurrent regulatory assets	2,996	3,360
Total regulatory liabilities	7,008	6,678
Less: current portion	473	255
Total noncurrent regulatory liabilities	6,535	6,423
Duke Energy Carolinas | Net regulatory liability related to income taxes
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	2,874	3,060
Duke Energy Carolinas | Costs of removal
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	1,975	1,936
Duke Energy Carolinas | AROs – nuclear and other
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	1,512	1,100
Duke Energy Carolinas | Provision for rate refunds
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	170	175
Duke Energy Carolinas | Accrued pension and OPEB
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	32	39
Duke Energy Carolinas | Deferred fuel and purchased power
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	18
Duke Energy Carolinas | Other
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	427	368
Duke Energy Carolinas | AROs – coal ash
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	1,414	1,696
Duke Energy Carolinas | Accrued pension and OPEB
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	427	477
Duke Energy Carolinas | Storm cost deferrals
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	205	178
Duke Energy Carolinas | Retired generation facilities
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	11	16
Duke Energy Carolinas | Post-in-service carrying costs (PISCC) and deferred operating expenses
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	32	33
Duke Energy Carolinas | Deferred asset – Lee and Harris COLA
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	324	350
Duke Energy Carolinas | Hedge costs deferrals
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	174	198
Duke Energy Carolinas | Advanced metering infrastructure (AMI)
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	154	166
Duke Energy Carolinas | Demand side management (DSM)/Energy Efficiency (EE)
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	46	100
Duke Energy Carolinas | Vacation accrual
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	84	80
Duke Energy Carolinas | Deferred fuel and purchased power
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	42	222
Duke Energy Carolinas | COR settlement
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	95	98
Duke Energy Carolinas | Nuclear deferral
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	88	67
Duke Energy Carolinas | Customer connect project
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	50	28
Duke Energy Carolinas | ABSAT, coal ash basin closure
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	71	50
Duke Energy Carolinas | Deferred severance charges
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	57
Duke Energy Carolinas | Incremental COVID-19 expenses
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	31
Duke Energy Carolinas | Other
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	164	151
Duke Energy Progress
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	4,468	4,678
Less: current portion	492	526
Total noncurrent regulatory assets	3,976	4,152
Total regulatory liabilities	4,924	4,468
Less: current portion	530	236
Total noncurrent regulatory liabilities	4,394	4,232
Duke Energy Progress | Net regulatory liability related to income taxes
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	1,662	1,802
Duke Energy Progress | Costs of removal
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	2,666	2,294
Duke Energy Progress | Provision for rate refunds
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	123	123
Duke Energy Progress | Other
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	473	249
Duke Energy Progress | AROs – coal ash
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	1,347	1,834
Duke Energy Progress | AROs – nuclear and other
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	683	509
Duke Energy Progress | Accrued pension and OPEB
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	393	423
Duke Energy Progress | Storm cost deferrals
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	785	801
Duke Energy Progress | Retired generation facilities
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	189	83
Duke Energy Progress | Post-in-service carrying costs (PISCC) and deferred operating expenses
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	51	33
Duke Energy Progress | Deferred asset – Lee and Harris COLA
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	32	38
Duke Energy Progress | Hedge costs deferrals
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	89	85
Duke Energy Progress | Advanced metering infrastructure (AMI)
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	57	61
Duke Energy Progress | Demand side management (DSM)/Energy Efficiency (EE)
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	224	216
Duke Energy Progress | Vacation accrual
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	42	41
Duke Energy Progress | Deferred fuel and purchased power
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	158	266
Duke Energy Progress | COR settlement
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	33	35
Duke Energy Progress | NCEMPA deferrals
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	124	72
Duke Energy Progress | Nuclear deferral
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	35	40
Duke Energy Progress | Customer connect project
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	25	17
Duke Energy Progress | ABSAT, coal ash basin closure
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	27	15
Duke Energy Progress | Deferred severance charges
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	29
Duke Energy Progress | Incremental COVID-19 expenses
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	23
Duke Energy Progress | Other
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	122	109
Duke Energy Florida
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	2,064	2,613
Less: current portion	265	419
Total noncurrent regulatory assets	1,799	2,194
Total regulatory liabilities	768	1,087
Less: current portion	110	94
Total noncurrent regulatory liabilities	658	993
Duke Energy Florida | Net regulatory liability related to income taxes
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	749	793
Duke Energy Florida | Costs of removal
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities		267
Duke Energy Florida | Deferred fuel and purchased power
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities		1
Duke Energy Florida | Other
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	19	26
Duke Energy Florida | AROs – coal ash
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	10	9
Duke Energy Florida | AROs – nuclear and other
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	2	159
Duke Energy Florida | Accrued pension and OPEB
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	482	474
Duke Energy Florida | Storm cost deferrals
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	108	413
Duke Energy Florida | Nuclear asset securitized balance, net
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	991	1,042
Duke Energy Florida | Retired generation facilities
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	174	183
Duke Energy Florida | Hedge costs deferrals
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	59	44
Duke Energy Florida | Advanced metering infrastructure (AMI)
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	45	53
Duke Energy Florida | Demand side management (DSM)/Energy Efficiency (EE)
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	17	25
Duke Energy Florida | Deferred fuel and purchased power
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	4	39
Duke Energy Florida | Qualifying facility contract buyouts
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	107	121
Duke Energy Florida | Customer connect project
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	30	20
Duke Energy Florida | Other
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	35	31
Duke Energy Ohio
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	649	598
Less: current portion	39	49
Total noncurrent regulatory assets	610	549
Total regulatory liabilities	813	827
Less: current portion	65	64
Total noncurrent regulatory liabilities	748	763
Duke Energy Ohio | Net regulatory liability related to income taxes
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	628	654
Duke Energy Ohio | Costs of removal
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	68	86
Duke Energy Ohio | Provision for rate refunds
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	45	31
Duke Energy Ohio | Accrued pension and OPEB
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	17	16
Duke Energy Ohio | Other
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	55	40
Duke Energy Ohio | AROs – coal ash
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	22	16
Duke Energy Ohio | Accrued pension and OPEB
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	149	155
Duke Energy Ohio | Storm cost deferrals
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	4	7
Duke Energy Ohio | Post-in-service carrying costs (PISCC) and deferred operating expenses
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	16	17
Duke Energy Ohio | Hedge costs deferrals
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	7	6
Duke Energy Ohio | Advanced metering infrastructure (AMI)
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	36	40
Duke Energy Ohio | Demand side management (DSM)/Energy Efficiency (EE)
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	1	2
Duke Energy Ohio | Vacation accrual
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	6	5
Duke Energy Ohio | Deferred fuel and purchased power
Regulatory Assets Liabilities [Line Items]
Total regulatory assets		1
Duke Energy Ohio | CEP deferral
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	117	76
Duke Energy Ohio | Manufactured gas plant (MGP)
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	104	102
Duke Energy Ohio | Deferred pipeline integrity costs
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	21	17
Duke Energy Ohio | Other
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	166	154
Duke Energy Indiana
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	1,328	1,172
Less: current portion	125	90
Total noncurrent regulatory assets	1,203	1,082
Total regulatory liabilities	1,738	1,740
Less: current portion	111	55
Total noncurrent regulatory liabilities	1,627	1,685
Duke Energy Indiana | Net regulatory liability related to income taxes
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	956	1,008
Duke Energy Indiana | Costs of removal
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	599	599
Duke Energy Indiana | Accrued pension and OPEB
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	100	90
Duke Energy Indiana | Amounts to be refunded to customers
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	17
Duke Energy Indiana | Other
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	66	43
Duke Energy Indiana | AROs – coal ash
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	615	529
Duke Energy Indiana | Accrued pension and OPEB
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	245	243
Duke Energy Indiana | Retired generation facilities
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	43	49
Duke Energy Indiana | Post-in-service carrying costs (PISCC) and deferred operating expenses
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	303	246
Duke Energy Indiana | Hedge costs deferrals
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	22	23
Duke Energy Indiana | Advanced metering infrastructure (AMI)
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	19	18
Duke Energy Indiana | Vacation accrual
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	12	12
Duke Energy Indiana | Deferred fuel and purchased power
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	9
Duke Energy Indiana | Other
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	60	52
Piedmont
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	455	363
Less: current portion	153	73
Total noncurrent regulatory assets	302	290
Total regulatory liabilities	1,132	1,212
Less: current portion	88	81
Total noncurrent regulatory liabilities	1,044	1,131
Piedmont | Net regulatory liability related to income taxes
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	499	555
Piedmont | Costs of removal
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	575	574
Piedmont | Provision for rate refunds
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	6	41
Piedmont | Accrued pension and OPEB
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	3	3
Piedmont | Amounts to be refunded to customers
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	34	34
Piedmont | Other
Regulatory Assets Liabilities [Line Items]
Total regulatory liabilities	15	5
Piedmont | AROs – nuclear and other
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	20	16
Piedmont | Accrued pension and OPEB
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	88	90
Piedmont | Vacation accrual
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	12	12
Piedmont | Derivatives – natural gas supply contracts
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	122	117
Piedmont | Amounts due from customers
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	110	36
Piedmont | Deferred pipeline integrity costs
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	71	62
Piedmont | Other
Regulatory Assets Liabilities [Line Items]
Total regulatory assets	$ 32	$ 30

Regulatory Matters (Narrative)

Regulatory Matters (Narrative) (Details) - USD ($) $ in Millions	Jan. 22, 2021	Oct. 26, 2020	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Public Utilities, General Disclosures [Line Items]
Impairment charges				$ 984	$ (8)	$ 402
Duke Energy Ohio
Public Utilities, General Disclosures [Line Items]
Limit of total capital			30.00%	30.00%
Duke Energy Kentucky
Public Utilities, General Disclosures [Line Items]
Required minimum equity capital structure			35.00%	35.00%
Duke Energy Carolinas
Public Utilities, General Disclosures [Line Items]
Impairment charges				$ 476	17	192
Duke Energy Carolinas | North Carolina Utilities Commission
Public Utilities, General Disclosures [Line Items]
Requested rate increase (decrease), amended, amount		$ 287
Duke Energy Carolinas | CCR Settlement Agreement
Public Utilities, General Disclosures [Line Items]
Impairment charges			$ 454
Reversal of regulated electric operating revenues			50
Duke Energy Progress
Public Utilities, General Disclosures [Line Items]
Impairment charges				$ 499	$ 12	$ 33
Duke Energy Progress | North Carolina Utilities Commission
Public Utilities, General Disclosures [Line Items]
Requested rate increase (decrease), amended, amount		$ 920
Duke Energy Progress | CCR Settlement Agreement
Public Utilities, General Disclosures [Line Items]
Impairment charges			494
Reversal of regulated electric operating revenues			$ 102
Duke Energy Carolinas and Duke Energy Progress | CCR Settlement Agreement | Subsequent Event
Public Utilities, General Disclosures [Line Items]
Recovery costs not sought	$ 1,000
Recovery costs amortization period	5 years
Equity return on deferred coal ash cost future cases	1.50%
Duke Energy Carolinas and Duke Energy Progress | CCR Settlement Agreement | NCUC | Subsequent Event
Public Utilities, General Disclosures [Line Items]
Requested capital structure, percentage	48.00%
Requested debt structure, percentage	52.00%

Regulatory Matters (Duke Energy

Regulatory Matters (Duke Energy Carolinas Narrative) (Details) - USD ($) $ in Millions

Oct. 26, 2020

Jul. 31, 2020

Sep. 30, 2019

May 21, 2019

Nov. 08, 2018

Jun. 22, 2018

Feb. 28, 2018

Aug. 25, 2017

Mar. 31, 2018

Dec. 31, 2020

Dec. 31, 2019

Dec. 31, 2018

Public Utilities, General Disclosures [Line Items]

Impairment charges

$ 984

$ (8)

$ 402

Regulatory assets

14,062

15,018

AROs – coal ash

Public Utilities, General Disclosures [Line Items]

Regulatory assets

3,408

4,084

Duke Energy Carolinas

Public Utilities, General Disclosures [Line Items]

Impairment charges

476

17

$ 192

Regulatory assets

3,469

3,910

Duke Energy Carolinas | AROs – coal ash

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 1,414

$ 1,696

Duke Energy Carolinas | NCUC | 2017 North Carolina Rate Case

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease)

$ 647

Requested return on equity, percentage

9.90%

Requested capital structure, percentage

52.00%

Requested debt structure, percentage

48.00%

Impairment charges

$ 150

$ 14

Management penalty assessed

70

Recovery costs reduction

$ 14

Recovery period

5 years

Duke Energy Carolinas | NCUC | 2019 North Carolina Rate Case

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease)

$ 291

Requested rate increase (decrease), percent

6.00%

Requested gross rate case revenue increase

$ 445

Requested EDIT rider decrease

$ 154

Duke Energy Carolinas | North Carolina Utilities Commission

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amended, amount

$ 287

Duke Energy Carolinas | North Carolina Utilities Commission | 2019 North Carolina Rate Case, Additional Agreement and Stipulation of Partial Settlement

Public Utilities, General Disclosures [Line Items]

Requested return on equity, percentage

9.60%

Requested capital structure, percentage

52.00%

Requested debt structure, percentage

48.00%

Requested rate increase (decrease), amended, amount

$ 800

Duke Energy Carolinas | North Carolina Utilities Commission | 2019 North Carolina Rate Case, Additional Agreement and Stipulation of Partial Settlement, Estimated Annual Revenue Requirement

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amended, amount

$ 45

Duke Energy Carolinas | PSCSC | 2018 South Carolina Rate Case

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease)

$ 168

Approved return on equity, percentage

9.50%

Approved capital structure, percentage

53.00%

Approved debt structure, percentage

47.00%

Tax benefit from change in enacted tax rates

$ (66)

Measurement period adjustment

$ (45)

Duke Energy Carolinas | PSCSC | 2018 South Carolina Rate Case | Deferred project costs

Public Utilities, General Disclosures [Line Items]

Recovery period

12 years

Regulatory assets

$ 125

Duke Energy Carolinas | PSCSC | 2018 South Carolina Rate Case | AROs – coal ash

Public Utilities, General Disclosures [Line Items]

Regulatory assets

96

Denied recovery costs

115

Duke Energy Carolinas | PSCSC | 2018 South Carolina Rate Case | State | North Carolina DOR

Public Utilities, General Disclosures [Line Items]

Approved decrease through EDIT Rider

$ 17

Regulatory Matters (Duke Ener_2

Regulatory Matters (Duke Energy Progress Narrative) (Details) $ in Millions

Oct. 26, 2020USD ($)

Oct. 16, 2020

Jul. 31, 2020USD ($)

Jun. 17, 2020USD ($)

Oct. 30, 2019USD ($)

Oct. 11, 2019

Sep. 30, 2019USD ($)

May 21, 2019USD ($)

Nov. 08, 2018USD ($)

Jun. 22, 2018USD ($)

Feb. 28, 2018

Nov. 22, 2017

Aug. 25, 2017USD ($)

Jun. 01, 2017USD ($)

Mar. 31, 2018USD ($)

Dec. 31, 2020USD ($)

Dec. 31, 2019USD ($)

Dec. 31, 2018USD ($)

Jul. 27, 2020MW

Jul. 01, 2020USD ($)

Feb. 07, 2020USD ($)

Jan. 29, 2020USD ($)MW

Public Utilities, General Disclosures [Line Items]

Impairment charges

$ 984

$ (8)

$ 402

Regulatory assets

14,062

15,018

Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Impairment charges

499

12

33

Regulatory assets

4,468

4,678

Duke Energy Carolinas

Public Utilities, General Disclosures [Line Items]

Impairment charges

476

17

$ 192

Regulatory assets

3,469

3,910

North Carolina Utilities Commission | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amended, amount

$ 920

North Carolina Utilities Commission | Duke Energy Carolinas

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amended, amount

$ 287

2017 North Carolina Rate Case | NCUC | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease)

$ 477

Requested rate increase (decrease), amended, amount

$ 420

Requested return on equity, percentage

9.90%

Requested capital structure, percentage

52.00%

Requested debt structure, percentage

48.00%

Impairment charges

$ 68

2017 North Carolina Rate Case | NCUC | Duke Energy Carolinas

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease)

$ 647

Requested return on equity, percentage

9.90%

Requested capital structure, percentage

52.00%

Requested debt structure, percentage

48.00%

Impairment charges

$ 150

$ 14

2019 North Carolina Rate Case | NCUC | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease)

$ 464

Requested rate increase (decrease), percent

12.30%

Requested gross rate case revenue increase

$ 586

Requested rate increase (decrease), rider reduction, tax cuts and jobs act and return deferred revenue

122

Requested EDIT rider decrease

$ 120

2019 North Carolina Rate Case | NCUC | Duke Energy Carolinas

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease)

$ 291

Requested rate increase (decrease), percent

6.00%

Requested gross rate case revenue increase

$ 445

Requested EDIT rider decrease

154

2019 North Carolina Rate Case, Additional Agreement and Stipulation of Partial Settlement | North Carolina Utilities Commission | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amended, amount

$ 500

Requested return on equity, percentage

9.60%

Requested capital structure, percentage

52.00%

Requested debt structure, percentage

48.00%

2019 North Carolina Rate Case, Additional Agreement and Stipulation of Partial Settlement | North Carolina Utilities Commission | Duke Energy Carolinas

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amended, amount

$ 800

Requested return on equity, percentage

9.60%

Requested capital structure, percentage

52.00%

Requested debt structure, percentage

48.00%

Hurricane Dorian Storm Damage | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Estimated storm costs - operation maintenance

168

Estimated storm costs - capital investments

$ 4

Hurricane Dorian Storm Damage | PSCSC | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Storm deferral - operation maintenance

$ 22

Storm deferral - requested supplemental true-up

$ 17

2018 South Carolina Rate Case | PSCSC | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease)

$ 59

Approved return on equity, percentage

9.50%

Approved capital structure, percentage

53.00%

Approved debt structure, percentage

47.00%

Tax benefit from change in enacted tax rates

$ (17)

Measurement period adjustment

$ (12)

2018 South Carolina Rate Case | PSCSC | Duke Energy Carolinas

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease)

$ 168

Approved return on equity, percentage

9.50%

Approved capital structure, percentage

53.00%

Approved debt structure, percentage

47.00%

Tax benefit from change in enacted tax rates

$ (66)

Measurement period adjustment

(45)

Western Carolinas Modernization Plan | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Solar generation capacity plants (in MW) | MW

5

FERC Return on Equity Complaint, North Carolina Eastern Municipal Power Agency | FERC | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Approved return on equity, percentage

11.00%

FERC Return on Equity Complaint, North Carolina Electric Membership Corporation | FERC | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Approved return on equity, percentage

11.00%

2019 North Carolina Rate Case, Additional Agreement and Stipulation of Partial Settlement, Estimated Annual Revenue Requirement | North Carolina Utilities Commission | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amended, amount

$ 25

2019 North Carolina Rate Case, Additional Agreement and Stipulation of Partial Settlement, Estimated Annual Revenue Requirement | North Carolina Utilities Commission | Duke Energy Carolinas

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amended, amount

$ 45

Storm cost deferrals

Public Utilities, General Disclosures [Line Items]

Regulatory assets

1,102

1,399

Storm cost deferrals | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Regulatory assets

785

801

Storm cost deferrals | Duke Energy Carolinas

Public Utilities, General Disclosures [Line Items]

Regulatory assets

205

178

Storm cost deferrals | Hurricane Dorian Storm Damage | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Regulatory assets

145

179

AROs – coal ash

Public Utilities, General Disclosures [Line Items]

Regulatory assets

3,408

4,084

AROs – coal ash | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Regulatory assets

1,347

1,834

AROs – coal ash | Duke Energy Carolinas

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 1,414

$ 1,696

AROs – coal ash | 2018 South Carolina Rate Case | PSCSC | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Regulatory assets

4

Denied recovery costs

65

AROs – coal ash | 2018 South Carolina Rate Case | PSCSC | Duke Energy Carolinas

Public Utilities, General Disclosures [Line Items]

Regulatory assets

96

Denied recovery costs

115

Ashville Depreciation Expense, Property Taxes, Incremental O&M and Carrying Costs | Western Carolinas Modernization Plan | PSCSC | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Public utilities, approved annual rate increase (decrease), amount

$ 8

State | North Carolina DOR | 2018 South Carolina Rate Case | PSCSC | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Approved increase (decrease) through EDIT Rider

12

State | North Carolina DOR | 2018 South Carolina Rate Case | PSCSC | Duke Energy Carolinas

Public Utilities, General Disclosures [Line Items]

Approved increase (decrease) through EDIT Rider

$ (17)

Asheville Plant | Western Carolinas Modernization Plan | Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Capacity of retired plant | MW

376

Generation facilities retired net

$ 214

Regulatory Matters (Duke Ener_3

Regulatory Matters (Duke Energy Florida Narrative) (Details)

Jan. 14, 2021USD ($)

Jul. 01, 2020USD ($)plantMW

Oct. 31, 2015USD ($)MW

Dec. 31, 2018USD ($)

Dec. 31, 2024USD ($)

Dec. 31, 2023USD ($)

Dec. 31, 2022USD ($)

Dec. 31, 2020USD ($)

Dec. 31, 2019USD ($)

Dec. 31, 2018USD ($)

May 19, 2020USD ($)

Apr. 02, 2020USD ($)

Dec. 19, 2019USD ($)

Nov. 22, 2019USD ($)

Apr. 30, 2019USD ($)

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 14,062,000,000

$ 15,018,000,000

Impairment charges

984,000,000

(8,000,000)

$ 402,000,000

Duke Energy Florida

Public Utilities, General Disclosures [Line Items]

Regulatory assets

2,064,000,000

2,613,000,000

Impairment charges

(4,000,000)

(36,000,000)

$ 54,000,000

Hurricane Dorian Storm Damage | Duke Energy Florida

Public Utilities, General Disclosures [Line Items]

Estimated storm costs, capital and operation maintenance

167,000,000

$ 169,000,000

FPSC | Duke Energy Florida

Public Utilities, General Disclosures [Line Items]

Accelerated fuel cost refund

$ 78,000,000

Solar generation capacity plants (in MW) | MW

750

Number of solar plants petition for approval | plant

10

FPSC | 2021 Settlement | Duke Energy Florida | Subsequent Event

Public Utilities, General Disclosures [Line Items]

Approved rate increase (decrease) amount by state commission

$ 79,000,000

$ 49,000,000

$ 67,000,000

Approved capital structure, percentage

53.00%

Approved debt structure, percentage

47.00%

Public utilities, basis points, increase

0.25%

Contract asset, noncurrent

$ 173,000,000

Future investments in new cost

$ 1,000,000,000

FPSC | 2021 Settlement | Duke Energy Florida | US Treasury Securities | Subsequent Event

Public Utilities, General Disclosures [Line Items]

Public utilities, basis points, increase

0.50%

FPSC | 2021 Settlement | Duke Energy Florida | Minimum | Subsequent Event

Public Utilities, General Disclosures [Line Items]

Approved return on equity, percentage

8.85%

FPSC | 2021 Settlement | Duke Energy Florida | Minimum | US Treasury Securities | Subsequent Event

Public Utilities, General Disclosures [Line Items]

Approved return on equity, percentage

9.85%

FPSC | 2021 Settlement | Duke Energy Florida | Maximum | Subsequent Event

Public Utilities, General Disclosures [Line Items]

Approved return on equity, percentage

10.85%

FPSC | 2021 Settlement | Duke Energy Florida | Maximum | US Treasury Securities | Subsequent Event

Public Utilities, General Disclosures [Line Items]

Approved return on equity, percentage

10.10%

FPSC | 2021 Settlement | Duke Energy Florida | Weighted Average | Subsequent Event

Public Utilities, General Disclosures [Line Items]

Approved return on equity, percentage

9.85%

FPSC | Hurricane Michael Storm Damage | Duke Energy Florida

Public Utilities, General Disclosures [Line Items]

Estimated storm costs, capital and operation maintenance

$ 223,000,000

Amount of recovery costs sought

$ 188,000,000

$ 191,000,000

Storm deferral - requested supplemental true-up

$ 3,000,000

FPSC | Hurricane Dorian Storm Damage | Duke Energy Florida

Public Utilities, General Disclosures [Line Items]

Storm Costs - Capital and Operation Maintenance

145,000,000

Solar Plant | Duke Energy Florida

Public Utilities, General Disclosures [Line Items]

Estimated cost of generation facilities to be built

$ 1,000,000,000

Estimated cost of generation facilities to be built, period

4 years

Natural Gas Plant | Duke Energy Florida

Public Utilities, General Disclosures [Line Items]

Estimated cost of generation facilities to be built

$ 1,500,000,000

Natural gas generation capacity plants (in MW) | MW

1,640

Cost of generation facilities to be built

$ 1,600,000,000

Impairment charges

$ 60,000,000

Impairment cost reversal

36,000,000

Storm cost deferrals

Public Utilities, General Disclosures [Line Items]

Regulatory assets

1,102,000,000

1,399,000,000

Storm cost deferrals | Duke Energy Florida

Public Utilities, General Disclosures [Line Items]

Regulatory assets

108,000,000

413,000,000

Storm cost deferrals | Hurricane Michael Storm Damage | Duke Energy Florida

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 80,000,000

$ 204,000,000

Regulatory Matters (Duke Ener_4

Regulatory Matters (Duke Energy Ohio Narrative) (Details) - USD ($) $ in Millions

Oct. 16, 2020

Apr. 27, 2020

Jan. 31, 2020

Sep. 03, 2019

Apr. 13, 2018

Apr. 01, 2018

Mar. 31, 2017

Dec. 31, 2020

Jul. 23, 2020

Dec. 31, 2019

Jul. 12, 2019

Dec. 31, 2018

Sep. 28, 2018

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 14,062

$ 15,018

Duke Energy Ohio

Public Utilities, General Disclosures [Line Items]

Regulatory assets

649

598

Duke Energy Ohio | RTO Realignment

Public Utilities, General Disclosures [Line Items]

Regulatory assets

37

40

Electric Base Rate Case | Public Utilities Commission Of Ohio | Duke Energy Ohio

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease)

$ 15

Requested return on equity, percentage

10.40%

Requested rate increase (decrease), amended, amount

$ (19)

Approved return on equity, percentage

9.84%

Requested capital structure, percentage

50.75%

Requested debt structure, percentage

49.25%

Approved rate increase (decrease) amount by state commission

$ (20)

MGP Cost Recovery - 2009 Through 2012 | Public Utilities Commission Of Ohio | Duke Energy Ohio

Public Utilities, General Disclosures [Line Items]

Regulatory assets

55

MGP Cost Recovery - 2013 Through 2017 | Public Utilities Commission Of Ohio | Duke Energy Ohio

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 26

MGP Cost Recovery - 2018 | Public Utilities Commission Of Ohio | Duke Energy Ohio

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 20

MGP Cost Recovery - 2019 | Public Utilities Commission Of Ohio | Duke Energy Ohio

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 39

Duke Energy Kentucky Electric Base Rate Case | KPSC | Duke Energy Kentucky

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease)

$ 44

$ 46

Approved return on equity, percentage

9.25%

Approved rate increase (decrease) amount by state commission

$ 28

$ 24

Additional approved rate increase (decrease), amount

$ 4

Minimum | Natural Gas Pipeline Extension | Ohio Power Siting Board | Duke Energy Ohio

Public Utilities, General Disclosures [Line Items]

Estimated capital cost excluding AFUDC

163

Maximum | Electric Base Rate Case | Public Utilities Commission Of Ohio | Duke Energy Ohio

Public Utilities, General Disclosures [Line Items]

Requested rider revenue increase

$ 10

Maximum | Natural Gas Pipeline Extension | Ohio Power Siting Board | Duke Energy Ohio

Public Utilities, General Disclosures [Line Items]

Estimated capital cost excluding AFUDC

$ 245

MGP Costs - Regulatory Disallowance | MGP Cost Recovery - 2013 Through 2017 | Public Utilities Commission Of Ohio | Duke Energy Ohio

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 12

MGP Costs - Regulatory Disallowance | MGP Cost Recovery - 2018 | Public Utilities Commission Of Ohio | Duke Energy Ohio

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 11

MGP Costs - Regulatory Disallowance | MGP Cost Recovery - 2019 | Public Utilities Commission Of Ohio | Duke Energy Ohio

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 4

Regulatory Matters (Duke Ener_5

Regulatory Matters (Duke Energy Ohio - Exit Obligation Rollforward) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)
Public Utilities, General Disclosures [Line Items]
Balance, beginning of period	$ 41
Cash reductions	(31)
Balance, end of period	11
Duke Energy Ohio
Public Utilities, General Disclosures [Line Items]
Balance, beginning of period	1
RTO Realignment | Duke Energy Ohio
Public Utilities, General Disclosures [Line Items]
Balance, beginning of period	54
Provisions/Adjustments	(1)
Cash reductions	(3)
Balance, end of period	$ 50

Regulatory Matters (Duke Ener_6

Regulatory Matters (Duke Energy Indiana Narrative) (Details) - Duke Energy Indiana - Indiana Rate Case 2019 - Indiana Utility Regulatory Commission - USD ($) $ in Millions	Jun. 29, 2020	Dec. 04, 2019	Jul. 02, 2019	Dec. 31, 2020
Public Utilities, General Disclosures [Line Items]
Requested rate increase (decrease)			$ 395
Requested rate increase (decrease), percentage, net of tax		15.60%
Requested rate increase (decrease), amended, amount		$ 396
Approved rate increase (decrease) amount by state commission	$ 146
Public utilities, approved rate increase (decrease)	5.70%
Approved return on equity, percentage	9.70%
Approved capital structure, percentage	53.00%
Disclosure of rate matters, rate base				$ 10,200
Public utilities, disclosure of rate matters, reduction of rate base	$ 200
Public utilities, disclosure of rate matters, rate base reduction due to depreciation methodology, percent	50.00%
Public utilities, disclosure of rate matters, rate base reduction due to approved return on equity, percent	20.00%
Requested return on equity, percentage	10.40%
Public utilities, disclosure of rate matters, rate base reduction due to earnings adjustments, percent	20.00%
Public utilities, approved return on equity, step one estimated percentage	75.00%
Public utilities, approved return on equity, step two estimated percentage	25.00%

Regulatory Matters (Piedmont Na

Regulatory Matters (Piedmont Narrative) (Details) - Piedmont - USD ($) $ in Millions	Feb. 16, 2021	Jul. 02, 2020	Aug. 13, 2019	Dec. 31, 2020
2020 Tennessee Rate Case | TPUC
Public Utilities, General Disclosures [Line Items]
Requested rate increase (decrease)		$ 30		$ 26
Increase in annual revenue		15.00%
2020 Tennessee Rate Case | TPUC | Subsequent Event
Public Utilities, General Disclosures [Line Items]
Requested rate increase (decrease)	$ 16
Requested return on equity, percentage	9.80%
2019 North Carolina Rate Case, Additional Agreement and Stipulation of Partial Settlement | North Carolina Utilities Commission
Public Utilities, General Disclosures [Line Items]
Requested return on equity, percentage			9.70%
Requested capital structure, percentage			52.00%
Requested debt structure, percentage			48.00%
Requested rate increase (decrease), amended, amount			$ 109
Requested EDIT rider decrease			(23)
Tax benefit from change in enacted tax rates			37
Cap on revenue increase			83
2019 North Carolina Rate Case, Additional Agreement and Stipulation of Partial Settlement | North Carolina DOR
Public Utilities, General Disclosures [Line Items]
Tax benefit from change in enacted tax rates			$ 21

Regulatory Matters (Other Regul

Regulatory Matters (Other Regulatory Matters Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Public Utilities, General Disclosures [Line Items]
Equity in losses of unconsolidated affiliates	$ 2,005	$ (162)	$ (83)
Income tax expense (benefit) from continuing operations	(236)	519	$ 448
Other	2,936	2,367
Asset retirement obligations	$ 718	$ 881
Atlantic Coast Pipeline (ACP)
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage	47.00%
Atlantic Coast Pipeline (ACP) | Atlantic Coast Pipeline (ACP)
Public Utilities, General Disclosures [Line Items]
Equity in losses of unconsolidated affiliates	$ 2,100
Income tax expense (benefit) from continuing operations	393
Restructuring and related cost, expected cost	20
Other	928
Other liabilities, noncurrent	8
Atlantic Coast Pipeline (ACP) | Atlantic Coast Pipeline (ACP) | Current Liabilities
Public Utilities, General Disclosures [Line Items]
Face value of guarantees	860
Asset retirement obligations	$ 76

Regulatory Matters (Schedule _2

Regulatory Matters (Schedule of Net Carrying Value Of Facilities) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2034asset	Dec. 31, 2020USD ($)MW	Dec. 31, 2019USD ($)
Public Utilities, General Disclosures [Line Items]
Remaining net book value		$ 106,782	$ 102,127
Generating facilities planned for retirement
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW		9,391
Remaining net book value		$ 6,402
Duke Energy Carolinas
Public Utilities, General Disclosures [Line Items]
Remaining net book value		$ 33,187	32,397
Duke Energy Carolinas | Allen Steam Station Units 1-3 | Generating facilities planned for retirement
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW		604
Remaining net book value		$ 113
Duke Energy Carolinas | Allen Steam Station Units 4-5 | Generating facilities planned for retirement
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW		526
Remaining net book value		$ 338
Duke Energy Carolinas | Cliffside Unit 5 | Generating facilities planned for retirement
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW		546
Remaining net book value		$ 350
Duke Energy Carolinas | Allen Steam Station 3 | Generating facilities planned for retirement
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW		270
Remaining net book value		$ 26
Duke Energy Progress
Public Utilities, General Disclosures [Line Items]
Remaining net book value		$ 22,987	22,934
Duke Energy Progress | Mayo Unit 1 | Generating facilities planned for retirement
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW		746
Remaining net book value		$ 676
Duke Energy Progress | Roxboro Units 3-4 | Generating facilities planned for retirement
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW		1,409
Remaining net book value		$ 484
Duke Energy Florida
Public Utilities, General Disclosures [Line Items]
Remaining net book value		$ 16,563	15,221
Duke Energy Florida | Crystal River Units 4 and 5 | Generating facilities planned for retirement
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW		1,430
Remaining net book value		$ 1,696
Duke Energy Florida | Crystal River Units 4 and 5 | Generating facilities planned for retirement | Forecast
Public Utilities, General Disclosures [Line Items]
Facilities retiring ahead of schedule | asset	2
Facilities retiring ahead of schedule, years ahead	8 years
Duke Energy Indiana
Public Utilities, General Disclosures [Line Items]
Remaining net book value		$ 11,721	$ 11,072
Duke Energy Indiana | Gallagher Units 2 and 4 | Generating facilities planned for retirement
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW		280
Remaining net book value		$ 102
Duke Energy Indiana | Gibson Units 1 - 5 | Generating facilities planned for retirement
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW		2,845
Remaining net book value		$ 1,866
Duke Energy Indiana | Cayuga Units 1 - 2 | Generating facilities planned for retirement
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW		1,005
Remaining net book value		$ 777

Commitments and Contingencies_2

Commitments and Contingencies (Narrative) (Details) $ in Millions	Jun. 18, 2018USD ($)	Dec. 31, 2020USD ($)reactorclaimplant	Dec. 31, 2019USD ($)
Insurance [Abstract]
Number of licensed nuclear reactors | reactor		97
Insured public liability limit per nuclear incident		$ 13,800
Excess nuclear liability program coverage		13,300
Pro rata assessment for each reactor owned for each incident exceeding public liability insurance		138
Annual payment limit to pro rata assessments		20.5
Industry aggregate limit		3,200
Sublimit for non-nuclear terrorist events		1,800
Sublimit property damage losses		1,500
Additional nuclear accident limit		$ 1,250
Accidental outage insurance coverage initial weeks		365 days
Accidental outage insurance coverage additional weeks		770 days
Weeks of sublimits for accidental outage coverage		728 days
Insurance coverage percentage initial weeks		100.00%
Insurance coverage percentage additional weeks		80.00%
Sublimit accidental outage recovery		$ 328
Maximum magnitude of retroactive premiums		10
Maximum period for retroactive premium assessment		6 years
Coal Ash Insurance Coverage Litigation
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Number of NC and SC plants with ash basins | plant		15
Duke Energy Carolinas
Insurance [Abstract]
Primary nuclear liability program coverage		$ 450
Max retroactive premium assessments		156
Duke Energy Carolinas | Asbestos Issue
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Asbestos-related injuries and damages reserves		572	$ 604
Reinsurance retention policy, excess retention, amount reinsured		714
Loss contingency, receivable, noncurrent		$ 704	$ 742
Duke Energy Carolinas | Asbestos Issue | Non Malignant Asbestos Claim
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Loss contingency, pending claims, number | claim		145
Asbestos-related injuries and damages reserves		$ 39
Duke Energy Carolinas | Asbestos Issue | Malignant Asbestos Claim
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Loss contingency, pending claims, number | claim		56
Asbestos-related injuries and damages reserves		$ 20
Duke Energy Carolinas | McGuire
Insurance [Abstract]
Number of licensed nuclear reactors | reactor		2
Accidental outage insurance coverage policy limit		$ 490
Duke Energy Carolinas | Catawba
Insurance [Abstract]
Number of licensed nuclear reactors | reactor		2
Dedicated additional nuclear accident limit		$ 1,250
Additional Non-nuclear accident limit		750
Accidental outage insurance coverage policy limit		$ 490
Potential obligation percentage		100.00%
Duke Energy Carolinas | Oconee
Insurance [Abstract]
Number of licensed nuclear reactors | reactor		3
Additional Non-nuclear accident limit		$ 750
Accidental outage insurance coverage policy limit		392
Duke Energy Progress
Insurance [Abstract]
Primary nuclear liability program coverage		450
Max retroactive premium assessments		$ 93
Duke Energy Progress | Spent Nuclear Fuel Matters
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Damages sought	$ 100
Duke Energy Progress | Robinson
Insurance [Abstract]
Number of licensed nuclear reactors | reactor		1
Accidental outage insurance coverage policy limit		$ 336
Duke Energy Progress | Harris
Insurance [Abstract]
Number of licensed nuclear reactors | reactor		1
Accidental outage insurance coverage policy limit		$ 434
Duke Energy Progress | Brunswick
Insurance [Abstract]
Number of licensed nuclear reactors | reactor		2
Accidental outage insurance coverage policy limit		$ 420
Duke Energy Florida
Insurance [Abstract]
Primary nuclear liability program coverage		100
Max retroactive premium assessments		1
Duke Energy Florida | Spent Nuclear Fuel Matters
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Damages sought	$ 200
Duke Energy Florida | Crystal River Unit 3
Insurance [Abstract]
Sublimit property damage losses		50
Duke Energy and Duke Energy Carolinas | ASU 2016-13
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Premium receivable, allowance for credit loss		$ 15

Commitments and Contingencies_3

Commitments and Contingencies (Schedule of Environmental Loss Contingencies) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disclosure Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	$ 75	$ 58
Duke Energy Carolinas
Disclosure Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	19	11
Progress Energy
Disclosure Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	19	16
Duke Energy Progress
Disclosure Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	6	4
Duke Energy Florida
Disclosure Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	12	9
Duke Energy Ohio
Disclosure Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	22	19
Duke Energy Indiana
Disclosure Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	6	4
Piedmont
Disclosure Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	10	$ 8
Environmental reserves
Disclosure Environmental Matters Details [Line Items]
Additional losses in excess of recorded reserves that could be incurred	25
Environmental reserves | Duke Energy Carolinas
Disclosure Environmental Matters Details [Line Items]
Additional losses in excess of recorded reserves that could be incurred	12
Environmental reserves | Duke Energy Ohio
Disclosure Environmental Matters Details [Line Items]
Additional losses in excess of recorded reserves that could be incurred	4
Environmental reserves | Piedmont
Disclosure Environmental Matters Details [Line Items]
Additional losses in excess of recorded reserves that could be incurred	$ 2

Commitments and Contingencies_4

Commitments and Contingencies (Schedule of Legal Reserves) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Legal Reserves Details [Line Items]
Reserves for Legal Matters	$ 68	$ 62
Duke Energy Carolinas
Legal Reserves Details [Line Items]
Reserves for Legal Matters	2	2
Progress Energy
Legal Reserves Details [Line Items]
Reserves for Legal Matters	61	55
Duke Energy Progress
Legal Reserves Details [Line Items]
Reserves for Legal Matters	13	12
Duke Energy Florida
Legal Reserves Details [Line Items]
Reserves for Legal Matters	28	22
Piedmont
Legal Reserves Details [Line Items]
Reserves for Legal Matters	$ 1	$ 1

Commitments and Contingencies_5

Commitments and Contingencies (Purchased Power) (Details) - Purchased Power Contracts $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)
Duke Energy Progress
Unconditional Purchase Obligations [Abstract]
2021	$ 66
2022	73
2023	66
2024	67
2025	69
Thereafter	69
Total	$ 410
Duke Energy Progress | Maximum
Unconditional Purchase Obligations [Abstract]
Net plant output percent	100.00%
Duke Energy Florida
Unconditional Purchase Obligations [Abstract]
2021	$ 335
2022	354
2023	374
2024	262
2025	91
Total	$ 1,416
Duke Energy Florida | Maximum
Unconditional Purchase Obligations [Abstract]
Net plant output percent	100.00%
Duke Energy Ohio
Unconditional Purchase Obligations [Abstract]
2021	$ 130
2022	55
Total	$ 185
Duke Energy Ohio | Minimum
Unconditional Purchase Obligations [Abstract]
Net plant output percent	1.00%
Duke Energy Ohio | Maximum
Unconditional Purchase Obligations [Abstract]
Net plant output percent	11.00%

Commitments and Contingencies_6

Commitments and Contingencies (Gas Supply Contracts) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)
Natural Gas Supply and Capacity Contracts
Long-term Purchase Commitment [Line Items]
2021	$ 311
2022	270
2023	197
2024	139
2025	125
Thereafter	662
Total	$ 1,704
Maximum | Pipeline and storage capacity contracts
Long-term Purchase Commitment [Line Items]
Long-term purchase commitment term	15 years
Maximum | Natural gas supply contracts fixed payment
Long-term Purchase Commitment [Line Items]
Long-term purchase commitment term	6 years
Maximum | Natural gas supply purchase commitments
Long-term Purchase Commitment [Line Items]
Long-term purchase commitment term	11 years
Duke Energy Ohio | Natural Gas Supply and Capacity Contracts
Long-term Purchase Commitment [Line Items]
2021	$ 41
2022	28
2023	20
2024	17
2025	14
Thereafter	60
Total	180
Piedmont | Natural Gas Supply and Capacity Contracts
Long-term Purchase Commitment [Line Items]
2021	270
2022	242
2023	177
2024	122
2025	111
Thereafter	602
Total	$ 1,524

Leases (Narrative) (Details)

Leases (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Lessee, Lease, Description [Line Items]
Operating lease assets, cost basis	$ 155,580	$ 147,654
Piedmont
Lessee, Lease, Description [Line Items]
Operating lease assets, cost basis	9,134	8,446
Construction and transportation of natural gas pipelines | Piedmont
Lessee, Lease, Description [Line Items]
Net investment in lease, current	2	4
Renewable energy projects
Lessee, Lease, Description [Line Items]
Contingent lease payments	275	264	$ 268
Operating lease assets, cost basis	3,335	3,349
Operating lease assets, accumulated depreciation	848	721
Duke Energy Carolinas | Construction and transportation of natural gas pipelines | Piedmont
Lessee, Lease, Description [Line Items]
Net investment in lease, noncurrent	$ 205	$ 70

Leases (Lease Costs) (Details)

Leases (Lease Costs) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Lessee, Lease, Description [Line Items]
Operating lease expense	$ 283	$ 292
Short-term lease expense	4	16
Variable lease expense	30	47
Finance lease expense
Amortization of leased assets	119	111
Interest on lease liabilities	61	61
Total finance lease expense	180	172
Total lease expense	497	527
Duke Energy Carolinas
Lessee, Lease, Description [Line Items]
Operating lease expense	53	47
Short-term lease expense		5
Variable lease expense	13	22
Finance lease expense
Amortization of leased assets	8	6
Interest on lease liabilities	30	15
Total finance lease expense	38	21
Total lease expense	104	95
Progress Energy
Lessee, Lease, Description [Line Items]
Operating lease expense	162	161
Short-term lease expense	2	9
Variable lease expense	13	22
Finance lease expense
Amortization of leased assets	24	21
Interest on lease liabilities	44	42
Total finance lease expense	68	63
Total lease expense	245	255
Duke Energy Progress
Lessee, Lease, Description [Line Items]
Operating lease expense	72	69
Short-term lease expense	1	4
Variable lease expense	5	16
Finance lease expense
Amortization of leased assets	6	5
Interest on lease liabilities	37	33
Total finance lease expense	43	38
Total lease expense	121	127
Duke Energy Florida
Lessee, Lease, Description [Line Items]
Operating lease expense	90	92
Short-term lease expense	1	5
Variable lease expense	8	6
Finance lease expense
Amortization of leased assets	18	16
Interest on lease liabilities	7	9
Total finance lease expense	25	25
Total lease expense	124	128
Duke Energy Ohio
Lessee, Lease, Description [Line Items]
Operating lease expense	11	11
Short-term lease expense	0	1
Variable lease expense	0
Finance lease expense
Amortization of leased assets	0	1
Interest on lease liabilities	0	0
Total finance lease expense	0	1
Total lease expense	11	13
Duke Energy Indiana
Lessee, Lease, Description [Line Items]
Operating lease expense	19	20
Short-term lease expense	1	2
Variable lease expense	1	1
Finance lease expense
Amortization of leased assets	1	0
Interest on lease liabilities	0	1
Total finance lease expense	1	1
Total lease expense	22	24
Piedmont
Lessee, Lease, Description [Line Items]
Operating lease expense	7	5
Short-term lease expense	0
Variable lease expense	1	1
Finance lease expense
Amortization of leased assets	0
Interest on lease liabilities	0	0
Total finance lease expense		0
Total lease expense	$ 8	$ 6

Leases (Rent Expense) (Details)

Leases (Rent Expense) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)
Operating Leased Assets [Line Items]
Rental expense on operating leases	$ 268
Duke Energy Carolinas
Operating Leased Assets [Line Items]
Rental expense on operating leases	49
Progress Energy
Operating Leased Assets [Line Items]
Rental expense on operating leases	143
Duke Energy Progress
Operating Leased Assets [Line Items]
Rental expense on operating leases	75
Duke Energy Florida
Operating Leased Assets [Line Items]
Rental expense on operating leases	68
Duke Energy Ohio
Operating Leased Assets [Line Items]
Rental expense on operating leases	13
Duke Energy Indiana
Operating Leased Assets [Line Items]
Rental expense on operating leases	21
Piedmont
Operating Leased Assets [Line Items]
Rental expense on operating leases	$ 11

Leases (Operating Lease Maturit

Leases (Operating Lease Maturities) (Details) $ in Millions	Dec. 31, 2020USD ($)
Lessee, Operating Lease, Liability, Payment, Due
2021	$ 229
2022	212
2023	202
2024	186
2025	162
Thereafter	870
Total operating lease payments	1,861
Less: present value discount	(344)
Total operating lease liabilities	1,517
Duke Energy Carolinas
Lessee, Operating Lease, Liability, Payment, Due
2021	24
2022	22
2023	20
2024	14
2025	10
Thereafter	51
Total operating lease payments	141
Less: present value discount	(24)
Total operating lease liabilities	117
Progress Energy
Lessee, Operating Lease, Liability, Payment, Due
2021	99
2022	95
2023	95
2024	95
2025	85
Thereafter	376
Total operating lease payments	845
Less: present value discount	(149)
Total operating lease liabilities	696
Duke Energy Progress
Lessee, Operating Lease, Liability, Payment, Due
2021	44
2022	40
2023	41
2024	41
2025	31
Thereafter	252
Total operating lease payments	449
Less: present value discount	(95)
Total operating lease liabilities	354
Duke Energy Florida
Lessee, Operating Lease, Liability, Payment, Due
2021	55
2022	55
2023	54
2024	54
2025	54
Thereafter	124
Total operating lease payments	396
Less: present value discount	(54)
Total operating lease liabilities	342
Duke Energy Ohio
Lessee, Operating Lease, Liability, Payment, Due
2021	2
2022	2
2023	2
2024	2
2025	2
Thereafter	20
Total operating lease payments	30
Less: present value discount	(9)
Total operating lease liabilities	21
Duke Energy Indiana
Lessee, Operating Lease, Liability, Payment, Due
2021	5
2022	4
2023	4
2024	4
2025	4
Thereafter	59
Total operating lease payments	80
Less: present value discount	(24)
Total operating lease liabilities	56
Piedmont
Lessee, Operating Lease, Liability, Payment, Due
2021	5
2022	5
2023	5
2024	5
2025	5
Total operating lease payments	25
Less: present value discount	(2)
Total operating lease liabilities	$ 23

Leases (Finance Lease Maturitie

Leases (Finance Lease Maturities) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Finance Lease, Liability, Payment, Due
2021	$ 186
2022	173
2023	174
2024	119
2025	51
Thereafter	762
Total finance lease payments	1,465
Less: amounts representing interest	(620)
Total finance lease liabilities	845	$ 969
Duke Energy Carolinas
Finance Lease, Liability, Payment, Due
2021	38
2022	38
2023	38
2024	38
2025	38
Thereafter	502
Total finance lease payments	692
Less: amounts representing interest	(398)
Total finance lease liabilities	294	179
Progress Energy
Finance Lease, Liability, Payment, Due
2021	68
2022	68
2023	68
2024	52
2025	48
Thereafter	481
Total finance lease payments	785
Less: amounts representing interest	(408)
Total finance lease liabilities	377	405
Duke Energy Progress
Finance Lease, Liability, Payment, Due
2021	43
2022	43
2023	43
2024	43
2025	43
Thereafter	475
Total finance lease payments	690
Less: amounts representing interest	(394)
Total finance lease liabilities	296	307
Duke Energy Florida
Finance Lease, Liability, Payment, Due
2021	25
2022	25
2023	25
2024	9
2025	5
Thereafter	6
Total finance lease payments	95
Less: amounts representing interest	(14)
Total finance lease liabilities	81	98
Duke Energy Indiana
Finance Lease, Liability, Payment, Due
2021	1
2022	1
2023	1
2024	1
2025	1
Thereafter	26
Total finance lease payments	31
Less: amounts representing interest	(21)
Total finance lease liabilities	$ 10	$ 10

Leases (Supplemental Financial

Leases (Supplemental Financial Information) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Assets
Operating lease right-of-use assets, net	$ 1,524	$ 1,658
Net property, plant and equipment	797	926
Total lease assets	2,321	2,584
Current
Operating	177	208
Finance	129	119
Noncurrent
Operating lease liabilities	1,340	1,432
Finance	716	850
Total lease liabilities	2,362	2,609
Cash paid for amounts included in the measurement of lease liabilities(a)
Operating cash flows from operating leases	271	285
Operating cash flows from finance leases	61	61
Financing cash flows from finance leases	119	111
Lease assets obtained in exchange for new lease liabilities (non-cash)
Operating, lease assets obtained	116	194
Finance	$ 125	$ 251
Weighted-average remaining lease term (years)
Operating leases	10 years	11 years
Finance leases	13 years	13 years
Weighted-average discount rate
Operating leases	3.80%	3.90%
Finance leases	8.40%	8.10%
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:PublicUtilitiesPropertyPlantAndEquipmentNet	us-gaap:PublicUtilitiesPropertyPlantAndEquipmentNet
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilitiesCurrent	us-gaap:OtherLiabilitiesCurrent
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:DebtCurrent	us-gaap:DebtCurrent
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	us-gaap:LongTermDebtNoncurrent	us-gaap:LongTermDebtNoncurrent
Duke Energy Carolinas
Assets
Operating lease right-of-use assets, net	$ 110	$ 123
Net property, plant and equipment	312	198
Total lease assets	422	321
Current
Operating	20	27
Finance	5	7
Noncurrent
Operating lease liabilities	97	102
Finance	289	172
Total lease liabilities	411	308
Cash paid for amounts included in the measurement of lease liabilities(a)
Operating cash flows from operating leases	31	34
Operating cash flows from finance leases	30	15
Financing cash flows from finance leases	8	6
Lease assets obtained in exchange for new lease liabilities (non-cash)
Operating, lease assets obtained	17	44
Finance	$ 125	$ 76
Weighted-average remaining lease term (years)
Operating leases	9 years	9 years
Finance leases	19 years	19 years
Weighted-average discount rate
Operating leases	3.40%	3.50%
Finance leases	11.60%	11.80%
Progress Energy
Assets
Operating lease right-of-use assets, net	$ 690	$ 788
Net property, plant and equipment	416	443
Total lease assets	1,106	1,231
Current
Operating	73	95
Finance	26	24
Noncurrent
Operating lease liabilities	623	697
Finance	351	381
Total lease liabilities	1,073	1,197
Cash paid for amounts included in the measurement of lease liabilities(a)
Operating cash flows from operating leases	124	131
Operating cash flows from finance leases	44	42
Financing cash flows from finance leases	$ 24	21
Lease assets obtained in exchange for new lease liabilities (non-cash)
Operating, lease assets obtained		30
Finance		$ 175
Weighted-average remaining lease term (years)
Operating leases	10 years	10 years
Finance leases	15 years	16 years
Weighted-average discount rate
Operating leases	3.80%	3.80%
Finance leases	11.90%	11.90%
Duke Energy Progress
Assets
Operating lease right-of-use assets, net	$ 346	$ 387
Net property, plant and equipment	297	308
Total lease assets	643	695
Current
Operating	31	37
Finance	7	6
Noncurrent
Operating lease liabilities	323	354
Finance	289	301
Total lease liabilities	650	698
Cash paid for amounts included in the measurement of lease liabilities(a)
Operating cash flows from operating leases	52	53
Operating cash flows from finance leases	37	33
Financing cash flows from finance leases	$ 6	5
Lease assets obtained in exchange for new lease liabilities (non-cash)
Operating, lease assets obtained		30
Finance		$ 175
Weighted-average remaining lease term (years)
Operating leases	12 years	12 years
Finance leases	17 years	18 years
Weighted-average discount rate
Operating leases	3.90%	3.90%
Finance leases	12.40%	12.40%
Duke Energy Florida
Assets
Operating lease right-of-use assets, net	$ 344	$ 401
Net property, plant and equipment	119	135
Total lease assets	463	536
Current
Operating	42	58
Finance	19	18
Noncurrent
Operating lease liabilities	300	343
Finance	62	80
Total lease liabilities	423	499
Cash paid for amounts included in the measurement of lease liabilities(a)
Operating cash flows from operating leases	72	78
Operating cash flows from finance leases	7	9
Financing cash flows from finance leases	$ 18	$ 16
Weighted-average remaining lease term (years)
Operating leases	8 years	8 years
Finance leases	11 years	11 years
Weighted-average discount rate
Operating leases	3.80%	3.80%
Finance leases	8.20%	8.30%
Duke Energy Ohio
Assets
Operating lease right-of-use assets, net	$ 20	$ 21
Total lease assets	20	21
Current
Operating	1	1
Noncurrent
Operating lease liabilities	20	21
Total lease liabilities	21	22
Cash paid for amounts included in the measurement of lease liabilities(a)
Operating cash flows from operating leases	$ 2	2
Financing cash flows from finance leases		$ 1
Weighted-average remaining lease term (years)
Operating leases	17 years	17 years
Weighted-average discount rate
Operating leases	4.20%	4.20%
Finance leases	0.00%	0.00%
Duke Energy Indiana
Assets
Operating lease right-of-use assets, net	$ 55	$ 57
Net property, plant and equipment	7	7
Total lease assets	62	64
Current
Operating	3	3
Noncurrent
Operating lease liabilities	53	55
Finance	10	10
Total lease liabilities	66	68
Cash paid for amounts included in the measurement of lease liabilities(a)
Operating cash flows from operating leases	6	7
Operating cash flows from finance leases		$ 1
Financing cash flows from finance leases	1
Lease assets obtained in exchange for new lease liabilities (non-cash)
Operating, lease assets obtained	$ 1
Weighted-average remaining lease term (years)
Operating leases	18 years	18 years
Finance leases	25 years	26 years
Weighted-average discount rate
Operating leases	4.20%	4.10%
Finance leases	11.90%	11.90%
Piedmont
Assets
Operating lease right-of-use assets, net	$ 20	$ 24
Total lease assets	20	24
Current
Operating	4	4
Noncurrent
Operating lease liabilities	19	23
Total lease liabilities	23	27
Cash paid for amounts included in the measurement of lease liabilities(a)
Operating cash flows from operating leases	$ 5	7
Lease assets obtained in exchange for new lease liabilities (non-cash)
Operating, lease assets obtained		$ 1
Weighted-average remaining lease term (years)
Operating leases	5 years	6 years
Weighted-average discount rate
Operating leases	3.60%	3.60%
Finance leases	0.00%	0.00%

Debt and Credit Facilities (Sum

Debt and Credit Facilities (Summary of Debt and Related Terms) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Weighted-average rate	3.62%	3.92%
Unsecured Debt	$ 23,669	$ 22,477
Secured Debt	4,270	4,537
First mortgage bonds	29,177	27,977
Finance leases	845	969
Tax exempt bonds	477	730
Notes payable and commercial paper	3,407	3,588
Money pool/intercompany borrowings	0
Fair value hedge carrying value adjustment	4	5
Unamortized debt discount and premium, net	1,217	1,294
Unamortized debt issuance costs	(330)	(316)
Total debt	62,736	61,261
Short-term notes payable and commercial paper	(2,873)	(3,135)
Current maturities of long-term debt	(4,238)	(3,141)
Total long-term debt	55,625	54,985
Short term obligations classified as long-term debt	$ 937	$ 937
Unsecured Debt
Debt Instrument [Line Items]
Weighted-average rate	3.71%	4.02%
Secured Debt
Debt Instrument [Line Items]
Weighted-average rate	2.67%	3.30%
First Mortgage Bonds
Debt Instrument [Line Items]
Weighted-average rate	4.00%	4.13%
Capital Lease Obligations
Debt Instrument [Line Items]
Weighted-average rate	6.96%	6.60%
Tax Exempt Bonds
Debt Instrument [Line Items]
Weighted-average rate	0.75%	2.90%
Short term obligations classified as long-term debt	$ 312	$ 312
Commercial Paper
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	$ 625	$ 625
Notes Payable And Commercial Paper
Debt Instrument [Line Items]
Weighted-average rate	0.51%	1.98%
Short term obligations classified as long-term debt	$ 625	$ 625
Weighted average days to maturity	23 days	14 days
Parent Company | Purchase Accounting Adjustments
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ 33	$ 37
Duke Energy Carolinas
Debt Instrument [Line Items]
Unsecured Debt	1,150	1,150
Secured Debt	543	544
First mortgage bonds	10,008	9,557
Finance leases	294	179
Tax exempt bonds		243
Money pool/intercompany borrowings	806	329
Fair value hedge carrying value adjustment	4	5
Unamortized debt discount and premium, net	(20)	(23)
Unamortized debt issuance costs	(62)	(55)
Total debt	12,723	11,929
Short-term money pool/intercompany borrowings	(506)	(29)
Current maturities of long-term debt	(506)	(458)
Total long-term debt	11,711	11,442
Short term obligations classified as long-term debt	300	300
Duke Energy Carolinas | Commercial Paper
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	300	300
Progress Energy
Debt Instrument [Line Items]
Unsecured Debt	3,150	3,650
Secured Debt	1,584	1,722
First mortgage bonds	14,100	13,800
Finance leases	377	405
Tax exempt bonds	48	48
Money pool/intercompany borrowings	3,119	1,970
Unamortized debt discount and premium, net	(31)	(29)
Unamortized debt issuance costs	(113)	(111)
Total debt	22,234	21,455
Short-term money pool/intercompany borrowings	(2,969)	(1,821)
Current maturities of long-term debt	(1,426)	(1,577)
Total long-term debt	17,839	18,057
Duke Energy Progress
Debt Instrument [Line Items]
Unsecured Debt	700	700
Secured Debt	252	335
First mortgage bonds	7,875	7,575
Finance leases	296	307
Tax exempt bonds	48	48
Money pool/intercompany borrowings	445	216
Unamortized debt discount and premium, net	(19)	(17)
Unamortized debt issuance costs	(44)	(40)
Total debt	9,553	9,124
Short-term money pool/intercompany borrowings	(295)	(66)
Current maturities of long-term debt	(603)	(1,006)
Total long-term debt	8,655	8,052
Short term obligations classified as long-term debt	150	150
Duke Energy Progress | Commercial Paper
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	150	150
Duke Energy Progress | Purchase Accounting Adjustments
Debt Instrument [Line Items]
Finance leases	24	44
Duke Energy Florida
Debt Instrument [Line Items]
Unsecured Debt	350	350
Secured Debt	1,332	1,387
First mortgage bonds	6,225	6,225
Finance leases	81	98
Money pool/intercompany borrowings	196
Unamortized debt discount and premium, net	(11)	(11)
Unamortized debt issuance costs	(62)	(62)
Total debt	8,111	7,987
Short-term money pool/intercompany borrowings	(196)
Current maturities of long-term debt	(823)	(571)
Total long-term debt	7,092	7,416
Duke Energy Florida | Purchase Accounting Adjustments
Debt Instrument [Line Items]
Finance leases	341	419
Duke Energy Ohio
Debt Instrument [Line Items]
Unsecured Debt	1,180	1,110
First mortgage bonds	1,850	1,449
Tax exempt bonds	77	77
Money pool/intercompany borrowings	194	337
Unamortized debt discount and premium, net	(29)	(30)
Unamortized debt issuance costs	(14)	(12)
Total debt	3,258	2,931
Short-term money pool/intercompany borrowings	(169)	(312)
Current maturities of long-term debt	(50)
Total long-term debt	3,039	2,619
Short term obligations classified as long-term debt	52	52
Duke Energy Ohio | Tax Exempt Bonds
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	27	27
Duke Energy Ohio | Commercial Paper
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	25	25
Duke Energy Indiana
Debt Instrument [Line Items]
Unsecured Debt	403	405
First mortgage bonds	3,219	3,169
Finance leases	10	10
Tax exempt bonds	352	362
Money pool/intercompany borrowings	281	180
Unamortized debt discount and premium, net	(18)	(19)
Unamortized debt issuance costs	(25)	(20)
Total debt	4,222	4,087
Short-term money pool/intercompany borrowings	(131)	(30)
Current maturities of long-term debt	(70)	(503)
Total long-term debt	4,021	3,554
Short term obligations classified as long-term debt	435	435
Duke Energy Indiana | Tax Exempt Bonds
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	285	285
Duke Energy Indiana | Commercial Paper
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	150	150
Piedmont
Debt Instrument [Line Items]
Unsecured Debt	2,800	2,399
Money pool/intercompany borrowings	530	476
Unamortized debt discount and premium, net	(5)	(2)
Unamortized debt issuance costs	(15)	(13)
Total debt	3,310	2,860
Short-term money pool/intercompany borrowings	(530)	(476)
Current maturities of long-term debt	(160)	0
Total long-term debt	2,620	2,384
Progress Energy | Purchase Accounting Adjustments
Debt Instrument [Line Items]
Unamortized debt discount and premium, net	1,196	1,275
Piedmont | Purchase Accounting Adjustments
Debt Instrument [Line Items]
Unamortized debt discount and premium, net	$ 117	$ 137

Debt and Credit Facilities (Ann

Debt and Credit Facilities (Annual Maturities) (Details) - USD ($)	Dec. 31, 2020	Oct. 31, 2020	Dec. 31, 2019
Current Maturities Of Long Term Debt [Abstract]
Current maturities of long-term debt	$ 4,238,000,000		$ 3,141,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
2021	4,238,000,000
2022	4,905,000,000
2023	3,356,000,000
2024	1,344,000,000
2025	3,153,000,000
Thereafter	41,983,000,000
Total long-term debt, including current maturities	58,979,000,000
Purchase accounting adjustments	(1,300,000,000)		(1,500,000,000)
Other
Current Maturities Of Long Term Debt [Abstract]
Current maturities of long-term debt	478,000,000
Purchase Accounting Adjustments
Long-term Debt, Fiscal Year Maturity [Abstract]
Purchase accounting adjustments	1,346,000,000
Progress Energy
Current Maturities Of Long Term Debt [Abstract]
Current maturities of long-term debt	1,426,000,000		1,577,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
2021	1,426,000,000
2022	1,736,000,000
2023	638,000,000
2024	76,000,000
2025	725,000,000
Thereafter	14,802,000,000
Total long-term debt, including current maturities	$ 19,403,000,000
Progress Energy | Unsecured Debt
Long-term Debt, Fiscal Year Maturity [Abstract]
Repurchase amount		$ 500,000,000
Duke Energy (Parent) | Debt Maturing May 2021 | Unsecured Debt
Current Maturities Of Long Term Debt [Abstract]
Interest Rate	0.721%
Current maturities of long-term debt	$ 500,000,000
Duke Energy (Parent) | Debt Maturing September 2021 | Unsecured Debt
Current Maturities Of Long Term Debt [Abstract]
Interest Rate	3.55%
Current maturities of long-term debt	$ 500,000,000
Duke Energy (Parent) | Debt Maturing September 2021 1.80% | Unsecured Debt
Current Maturities Of Long Term Debt [Abstract]
Interest Rate	1.80%
Current maturities of long-term debt	$ 750,000,000
Piedmont
Current Maturities Of Long Term Debt [Abstract]
Current maturities of long-term debt	160,000,000		0
Long-term Debt, Fiscal Year Maturity [Abstract]
2021	160,000,000
2023	45,000,000
2024	40,000,000
2025	205,000,000
Thereafter	2,350,000,000
Total long-term debt, including current maturities	$ 2,800,000,000
Piedmont | Debt Maturing June 2021 | Unsecured Debt
Current Maturities Of Long Term Debt [Abstract]
Interest Rate	4.24%
Current maturities of long-term debt	$ 160,000,000
Duke Energy Florida
Current Maturities Of Long Term Debt [Abstract]
Current maturities of long-term debt	823,000,000		571,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
2021	823,000,000
2022	78,000,000
2023	77,000,000
2024	66,000,000
2025	64,000,000
Thereafter	6,878,000,000
Total long-term debt, including current maturities	$ 7,986,000,000
Duke Energy Florida | Debt Maturing November 2021 | Unsecured Debt
Current Maturities Of Long Term Debt [Abstract]
Interest Rate	0.482%
Current maturities of long-term debt	$ 200,000,000
Duke Energy Florida | Debt Maturing April 2021 | Secured Debt
Current Maturities Of Long Term Debt [Abstract]
Interest Rate	0.972%
Current maturities of long-term debt	$ 250,000,000
Duke Energy Florida | Debt Maturing August 2021 | First Mortgage Bonds
Current Maturities Of Long Term Debt [Abstract]
Interest Rate	3.10%
Current maturities of long-term debt	$ 300,000,000
Duke Energy Carolinas
Current Maturities Of Long Term Debt [Abstract]
Current maturities of long-term debt	506,000,000		458,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
2021	506,000,000
2022	721,000,000
2023	1,008,000,000
2024	9,000,000
2025	310,000,000
Thereafter	9,745,000,000
Total long-term debt, including current maturities	$ 12,299,000,000
Duke Energy Carolinas | Debt Maturing June 2021 | First Mortgage Bonds
Current Maturities Of Long Term Debt [Abstract]
Interest Rate	3.90%
Current maturities of long-term debt	$ 500,000,000
Duke Energy Progress
Current Maturities Of Long Term Debt [Abstract]
Current maturities of long-term debt	603,000,000		1,006,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
2021	603,000,000
2022	1,208,000,000
2023	561,000,000
2024	10,000,000
2025	661,000,000
Thereafter	6,274,000,000
Total long-term debt, including current maturities	$ 9,317,000,000
Duke Energy Progress | Debt Maturing September 2021 | First Mortgage Bonds
Current Maturities Of Long Term Debt [Abstract]
Interest Rate	3.00%
Current maturities of long-term debt	$ 500,000,000
Duke Energy Progress | Debt Maturing September 2021 | First Mortgage Bonds
Current Maturities Of Long Term Debt [Abstract]
Interest Rate	8.625%
Current maturities of long-term debt	$ 100,000,000
Duke Energy Ohio
Current Maturities Of Long Term Debt [Abstract]
Current maturities of long-term debt	50,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
2021	50,000,000
2023	325,000,000
2025	270,000,000
Thereafter	2,486,000,000
Total long-term debt, including current maturities	3,131,000,000
Duke Energy Indiana
Current Maturities Of Long Term Debt [Abstract]
Current maturities of long-term debt	70,000,000		$ 503,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
2021	70,000,000
2022	84,000,000
2023	3,000,000
2024	4,000,000
2025	154,000,000
Thereafter	3,818,000,000
Total long-term debt, including current maturities	$ 4,133,000,000

Debt and Credit Facilities (Sho

Debt and Credit Facilities (Short Term Obligations Classified As Long Term) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	$ 937	$ 937
Tax Exempt Bonds
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	312	312
Commercial Paper
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	625	625
Duke Energy Carolinas
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	300	300
Duke Energy Carolinas | Commercial Paper
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	300	300
Duke Energy Progress
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	150	150
Duke Energy Progress | Commercial Paper
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	150	150
Duke Energy Ohio
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	52	52
Duke Energy Ohio | Tax Exempt Bonds
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	27	27
Duke Energy Ohio | Commercial Paper
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	25	25
Duke Energy Indiana
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	435	435
Duke Energy Indiana | Tax Exempt Bonds
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	285	285
Duke Energy Indiana | Commercial Paper
Debt Instrument [Line Items]
Short term obligations classified as long-term debt	$ 150	$ 150

Debt and Credit Facilities (S_2

Debt and Credit Facilities (Summary of Debt Issuances) (Details) - USD ($)	1 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Debt issuances		$ 5,550,000,000	$ 6,210,000,000
Repayments of long-term debt		$ 4,506,000,000	$ 3,476,000,000	$ 2,906,000,000
May 2020 Debt Issuance Due June 2030 | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate		2.45%
Debt issuances		$ 500,000,000
May 2020 Debt Issuance Due June 2030 | First Mortgage Bonds
Debt Instrument [Line Items]
Interest Rate		2.125%
Debt issuances		$ 400,000,000
May 2020 Debt Issuance Due June 2050 | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate		3.35%
Debt issuances		$ 400,000,000
August 2020 Debt Issuance Due February 2022 | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate		0.40%
Debt issuances		$ 700,000,000
September 2020 Debt Issuance Due September 2025 | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate		0.90%
Debt issuances		$ 650,000,000
September 2020 Debt Issuance Due June 2030 | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate		2.45%
Debt issuances		$ 350,000,000
January 2020 Debt Issuance 2.450% Coupon Due 2030 | First Mortgage Bonds
Debt Instrument [Line Items]
Interest Rate		2.45%
Debt issuances		$ 500,000,000
January 2020 Debt Issuance 3.20% Due August 2049 | First Mortgage Bonds
Debt Instrument [Line Items]
Interest Rate		3.20%
Debt issuances		$ 400,000,000
March 2020 Debt Issuance 2.750% Due April 2050 | First Mortgage Bonds
Debt Instrument [Line Items]
Interest Rate		2.75%
Debt issuances		$ 550,000,000
June 2020 Debt Issuance Due June 2030 | First Mortgage Bonds
Debt Instrument [Line Items]
Interest Rate		1.75%
Debt issuances		$ 500,000,000
August 2020 Debt Issuance Due August 2050 | First Mortgage Bonds
Debt Instrument [Line Items]
Interest Rate		2.50%
Debt issuances		$ 600,000,000
March 2019 Debt Issuance Due March 2022
Debt Instrument [Line Items]
Interest Rate			2.538%
March 2019 Debt Issuance Due March 2022 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 300,000,000
March 2019 Debt Issuance 3.227% Coupon Due 2022
Debt Instrument [Line Items]
Interest Rate			3.227%
March 2019 Debt Issuance 3.227% Coupon Due 2022 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 300,000,000
May 2019 Debt Issuance 3.500% Coupon Due 2029
Debt Instrument [Line Items]
Interest Rate			3.50%
May 2019 Debt Issuance 3.500% Coupon Due 2029 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 600,000,000
June 2019 Debt Issuance 3.400% Coupon Due 2029
Debt Instrument [Line Items]
Interest Rate			3.40%
June 2019 Debt Issuance 3.400% Coupon Due 2029 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 600,000,000
June 2019 Debt Issuance 4.200% Coupon Due 2049
Debt Instrument [Line Items]
Interest Rate			4.20%
June 2019 Debt Issuance 4.200% Coupon Due 2049 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 600,000,000
July 2019 Debt Issuance 4.320% Coupon Due 2049
Debt Instrument [Line Items]
Interest Rate			4.32%
July 2019 Debt Issuance 4.320% Coupon Due 2049 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 40,000,000
September 2019 Debt Issuance 3.230% Coupon Due 2025
Debt Instrument [Line Items]
Interest Rate			3.23%
September 2019 Debt Issuance 3.230% Coupon Due 2025 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 95,000,000
September 2019 Debt Issuance 3.560% Coupon Due 2029
Debt Instrument [Line Items]
Interest Rate			3.56%
September 2019 Debt Issuance 3.560% Coupon Due 2029 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 75,000,000
November 2019 Debt Issuance 2.167% Coupon Due 2021
Debt Instrument [Line Items]
Interest Rate			2.167%
November 2019 Debt Issuance 2.167% Coupon Due 2021 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 200,000,000
January 2019 Debt Issuance 3.650% Coupon Due 2029
Debt Instrument [Line Items]
Interest Rate			3.65%
January 2019 Debt Issuance 3.650% Coupon Due 2029 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			$ 400,000,000
January 2019 Debt Issuance 4.300% Coupon Due 2049
Debt Instrument [Line Items]
Interest Rate			4.30%
January 2019 Debt Issuance 4.300% Coupon Due 2049 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			$ 400,000,000
March 2019 Debt Issuance 3.450% Coupon Due 2029
Debt Instrument [Line Items]
Interest Rate			3.45%
March 2019 Debt Issuance 3.450% Coupon Due 2029 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			$ 600,000,000
August 2019 Debt Issuance 2.450% Coupon Due 2029
Debt Instrument [Line Items]
Interest Rate			2.45%
August 2019 Debt Issuance 2.450% Coupon Due 2029 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			$ 450,000,000
August 2019 Debt Issuance 3.200% Coupon Due 2049
Debt Instrument [Line Items]
Interest Rate			3.20%
August 2019 Debt Issuance 3.200% Coupon Due 2049 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			$ 350,000,000
September 2019 Debt Issuance 3.250% Coupon Due 2049
Debt Instrument [Line Items]
Interest Rate			3.25%
September 2019 Debt Issuance 3.250% Coupon Due 2049 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			$ 500,000,000
November 2019 Debt Issuance 2.500% Coupon Due 2029
Debt Instrument [Line Items]
Interest Rate			2.50%
November 2019 Debt Issuance 2.500% Coupon Due 2029 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			$ 700,000,000
Parent Company
Debt Instrument [Line Items]
Debt issuances		1,500,000,000	1,800,000,000
Parent Company | May 2020 Debt Issuance Due June 2030 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances		500,000,000
Parent Company | September 2020 Debt Issuance Due September 2025 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances		650,000,000
Parent Company | September 2020 Debt Issuance Due June 2030 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances		350,000,000
Parent Company | March 2019 Debt Issuance Due March 2022 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			300,000,000
Parent Company | March 2019 Debt Issuance 3.227% Coupon Due 2022 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			300,000,000
Parent Company | June 2019 Debt Issuance 3.400% Coupon Due 2029 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			600,000,000
Parent Company | June 2019 Debt Issuance 4.200% Coupon Due 2049 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			600,000,000
Duke Energy Carolinas
Debt Instrument [Line Items]
Debt issuances		900,000,000	800,000,000
Repayments of long-term debt		813,000,000	6,000,000	1,205,000,000
Duke Energy Carolinas | January 2020 Debt Issuance 2.450% Coupon Due 2030 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances		500,000,000
Duke Energy Carolinas | January 2020 Debt Issuance 3.20% Due August 2049 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances		400,000,000
Duke Energy Carolinas | Bonds Maturing June 2020, 4.300% Coupon | First Mortgage Bonds
Debt Instrument [Line Items]
Repayments of long-term debt	$ 450,000,000
Duke Energy Carolinas | August 2019 Debt Issuance 2.450% Coupon Due 2029 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			450,000,000
Duke Energy Carolinas | August 2019 Debt Issuance 3.200% Coupon Due 2049 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			350,000,000
Duke Energy Progress
Debt Instrument [Line Items]
Debt issuances		1,300,000,000	600,000,000
Repayments of long-term debt		1,085,000,000	605,000,000	3,000,000
Duke Energy Progress | Term Loan
Debt Instrument [Line Items]
Repayments of long-term debt		700,000,000
Duke Energy Progress | August 2020 Debt Issuance Due February 2022 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances		700,000,000
Duke Energy Progress | August 2020 Debt Issuance Due August 2050 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances		600,000,000
Duke Energy Progress | Bonds Due September 2020 | First Mortgage Bonds
Debt Instrument [Line Items]
Repayments of long-term debt		300,000,000
Duke Energy Progress | March 2019 Debt Issuance 3.450% Coupon Due 2029 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			600,000,000
Duke Energy Florida
Debt Instrument [Line Items]
Debt issuances		500,000,000	900,000,000
Repayments of long-term debt		572,000,000	262,000,000	769,000,000
Duke Energy Florida | June 2020 Debt Issuance Due June 2030 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances		500,000,000
Duke Energy Florida | November 2019 Debt Issuance 2.167% Coupon Due 2021 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			200,000,000
Duke Energy Florida | November 2019 Debt Issuance 2.500% Coupon Due 2029 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			700,000,000
Duke Energy Ohio
Debt Instrument [Line Items]
Debt issuances		400,000,000	1,010,000,000
Repayments of long-term debt			551,000,000	3,000,000
Duke Energy Ohio | May 2020 Debt Issuance Due June 2030 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances		400,000,000
Duke Energy Ohio | July 2019 Debt Issuance 4.320% Coupon Due 2049 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			40,000,000
Duke Energy Ohio | September 2019 Debt Issuance 3.230% Coupon Due 2025 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			95,000,000
Duke Energy Ohio | September 2019 Debt Issuance 3.560% Coupon Due 2029 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			75,000,000
Duke Energy Ohio | January 2019 Debt Issuance 3.650% Coupon Due 2029 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			400,000,000
Duke Energy Ohio | January 2019 Debt Issuance 4.300% Coupon Due 2049 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			400,000,000
Duke Energy Ohio | April 2019 First Mortgage Bonds
Debt Instrument [Line Items]
Repayments of long-term debt			450,000,000
Duke Energy Ohio | Debentures Due October 2019
Debt Instrument [Line Items]
Repayments of long-term debt			100,000,000
Duke Energy Indiana
Debt Instrument [Line Items]
Debt issuances		550,000,000	500,000,000
Repayments of long-term debt		513,000,000	213,000,000	$ 3,000,000
Duke Energy Indiana | March 2020 Debt Issuance 2.750% Due April 2050 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances		550,000,000
Duke Energy Indiana | Bonds Due July 2020 | First Mortgage Bonds
Debt Instrument [Line Items]
Repayments of long-term debt		500,000,000
Duke Energy Indiana | September 2019 Debt Issuance 3.250% Coupon Due 2049 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			500,000,000
Duke Energy Indiana | Pollution Control Bonds
Debt Instrument [Line Items]
Repayments of long-term debt			150,000,000
Piedmont
Debt Instrument [Line Items]
Debt issuances		400,000,000	600,000,000
Repayments of long-term debt			350,000,000
Piedmont | May 2020 Debt Issuance Due June 2050 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances		400,000,000
Piedmont | May 2019 Debt Issuance 3.500% Coupon Due 2029 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			600,000,000
Piedmont | Senior Unsecured Term Loan Facility Due September 2019
Debt Instrument [Line Items]
Repayments of long-term debt			$ 350,000,000
Duke Energy (Parent) | Term Loan Due March 2021
Debt Instrument [Line Items]
Repayments of long-term debt		1,700,000,000
Revolving Credit Facility | Duke Energy (Parent)
Debt Instrument [Line Items]
Repayments of long-term debt		$ 500,000,000

Debt and Credit Facilities (Sch

Debt and Credit Facilities (Schedule of Line of Credit Facilities) (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Line of Credit Facility [Line Items]
Tax-exempt bonds	$ (477,000,000)	$ (730,000,000)
Duke Energy Carolinas
Line of Credit Facility [Line Items]
Tax-exempt bonds		(243,000,000)
Duke Energy Progress
Line of Credit Facility [Line Items]
Tax-exempt bonds	(48,000,000)	(48,000,000)
Duke Energy Ohio
Line of Credit Facility [Line Items]
Tax-exempt bonds	(77,000,000)	(77,000,000)
Duke Energy Indiana
Line of Credit Facility [Line Items]
Tax-exempt bonds	(352,000,000)	$ (362,000,000)
Revolving Credit Facility
Line of Credit Facility [Line Items]
Facility size	8,000,000,000		$ 8,000,000,000
Commercial paper	(2,239,000,000)
Outstanding letters of credit	(40,000,000)
Tax-exempt bonds	(81,000,000)
Available capacity	5,640,000,000
Revolving Credit Facility | Parent Company
Line of Credit Facility [Line Items]
Facility size	2,650,000,000
Outstanding letters of credit	(34,000,000)
Available capacity	2,616,000,000
Revolving Credit Facility | Duke Energy Carolinas
Line of Credit Facility [Line Items]
Facility size	1,475,000,000
Commercial paper	(736,000,000)
Outstanding letters of credit	(4,000,000)
Available capacity	735,000,000
Revolving Credit Facility | Duke Energy Progress
Line of Credit Facility [Line Items]
Facility size	1,250,000,000
Commercial paper	(407,000,000)
Outstanding letters of credit	(2,000,000)
Available capacity	841,000,000
Revolving Credit Facility | Duke Energy Florida
Line of Credit Facility [Line Items]
Facility size	800,000,000
Commercial paper	(179,000,000)
Available capacity	621,000,000
Revolving Credit Facility | Duke Energy Ohio
Line of Credit Facility [Line Items]
Facility size	625,000,000
Commercial paper	(176,000,000)
Available capacity	449,000,000
Revolving Credit Facility | Duke Energy Indiana
Line of Credit Facility [Line Items]
Facility size	600,000,000
Commercial paper	(257,000,000)
Tax-exempt bonds	(81,000,000)
Available capacity	262,000,000
Revolving Credit Facility | Piedmont
Line of Credit Facility [Line Items]
Facility size	600,000,000
Commercial paper	(484,000,000)
Available capacity	116,000,000
Proceeds Loaned To Subsidiary Registrants | Revolving Credit Facility | Parent Company
Line of Credit Facility [Line Items]
Commercial paper	$ (625,000,000)

Debt and Credit Facilities (Nar

Debt and Credit Facilities (Narrative) (Details)	Aug. 31, 2020USD ($)	Mar. 27, 2020USD ($)	Mar. 19, 2020USD ($)	Jun. 30, 2020USD ($)	Dec. 31, 2020USD ($)	Mar. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Debt Instrument [Line Items]
Demand notes, maximum amount available for sale					$ 3,000,000,000
Demand notes, maximum amount outstanding					1,500,000,000
Principal amount of demand notes					1,168,000,000		$ 1,049,000,000
Other loans outstanding against cash surrender value of life insurance policies					$ 817,000,000		777,000,000
Maximum
Debt Instrument [Line Items]
Debt to total capitalization percentage, for each borrower					0.65
June 2017 Three Year Revolving Credit Facility
Debt Instrument [Line Items]
Facility size					$ 1,000,000,000
Term of debt instrument					3 years
Long-term line of credit					$ 500,000,000	$ 500,000,000
Repayments of debt				$ 500,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Facility size					8,000,000,000			$ 8,000,000,000
Duke Energy (Parent) | Line of Credit | 364-day Term Loan Credit Agreement
Debt Instrument [Line Items]
Facility size						1,500,000,000
Drawings on credit facility		$ 188,000,000	$ 1,500,000,000
Line of credit facility, increase limit						$ 500,000,000
Duke Energy Progress
Debt Instrument [Line Items]
Other loans outstanding against cash surrender value of life insurance policies					$ 35,000,000		36,000,000
Duke Energy Progress | Maximum
Debt Instrument [Line Items]
Debt to total capitalization percentage, for each borrower					0.65
Duke Energy Progress | Revolving Credit Facility
Debt Instrument [Line Items]
Facility size					$ 1,250,000,000
Duke Energy Progress | Revolving Credit Facility | Line of Credit
Debt Instrument [Line Items]
Facility size									$ 700,000,000
Term of debt instrument					2 years
Long-term line of credit							$ 700,000,000
Repayments of debt	$ 700,000,000
Piedmont | Maximum
Debt Instrument [Line Items]
Debt to total capitalization percentage, for each borrower					0.70
Piedmont | Revolving Credit Facility
Debt Instrument [Line Items]
Facility size					$ 600,000,000
Duke Energy Carolinas | Maximum
Debt Instrument [Line Items]
Debt to total capitalization percentage, for each borrower					0.65
Duke Energy Carolinas | Revolving Credit Facility
Debt Instrument [Line Items]
Facility size					$ 1,475,000,000
Progress Energy | Maximum
Debt Instrument [Line Items]
Debt to total capitalization percentage, for each borrower					0.65
Duke Energy Florida | Maximum
Debt Instrument [Line Items]
Debt to total capitalization percentage, for each borrower					0.65
Duke Energy Florida | Revolving Credit Facility
Debt Instrument [Line Items]
Facility size					$ 800,000,000
Duke Energy Ohio | Maximum
Debt Instrument [Line Items]
Debt to total capitalization percentage, for each borrower					0.65
Duke Energy Ohio | Revolving Credit Facility
Debt Instrument [Line Items]
Facility size					$ 625,000,000
Duke Energy Indiana | Maximum
Debt Instrument [Line Items]
Debt to total capitalization percentage, for each borrower					0.65
Duke Energy Indiana | Revolving Credit Facility
Debt Instrument [Line Items]
Facility size					$ 600,000,000

Guarantees and Indemnificatio_2

Guarantees and Indemnifications (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Jul. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Oct. 31, 2017
Guarantor Obligations [Line Items]
Unused letters of credit	$ 76
Noncurrent Liabilities
Guarantor Obligations [Line Items]
Face value of guarantees	11			$ 23
Off-balance sheet, credit loss, liability	4
Letters of credit
Guarantor Obligations [Line Items]
Maximum potential amount of future payments associated with guarantees	566
ACP
Guarantor Obligations [Line Items]
Maximum borrowing capacity		$ 1,900			$ 3,400
Atlantic Coast Pipeline (ACP) | Atlantic Coast Pipeline (ACP)
Guarantor Obligations [Line Items]
Off-balance sheet, credit loss, liability			$ 95
Atlantic Coast Pipeline (ACP) | Current Liabilities | Atlantic Coast Pipeline (ACP)
Guarantor Obligations [Line Items]
Face value of guarantees	860
Performance guarantee
Guarantor Obligations [Line Items]
Maximum potential of future amounts associated with guarantees with expiration dates	53
Performance guarantee | Customers and other third parties
Guarantor Obligations [Line Items]
Maximum potential amount of future payments associated with guarantees	56
Performance guarantee | Spectra Capital
Guarantor Obligations [Line Items]
Maximum potential amount of future payments associated with guarantees	56
Financial guarantee | ACP
Guarantor Obligations [Line Items]
Maximum potential amount of future payments associated with guarantees	$ 860
Maximum exposure percentage	47.00%

Joint Ownership of Generating_3

Joint Ownership of Generating and Transmission Facilities (Schedule Joint Ownership of Generating and Transmission Facilities) (Details) $ in Millions	Dec. 31, 2020USD ($)
Duke Energy Carolinas | Catawba (units 1 and 2)
Jointly Owned Utility Plant Interests [Line Items]
Ownership interest	19.25%
Property, plant, and equipment	$ 1,017
Accumulated depreciation	518
Construction work in progress	$ 23
Duke Energy Carolinas | W.S. Lee CC
Jointly Owned Utility Plant Interests [Line Items]
Ownership interest	87.27%
Property, plant, and equipment	$ 632
Accumulated depreciation	49
Construction work in progress	$ 1
Duke Energy Indiana | Gibson (unit 5)
Jointly Owned Utility Plant Interests [Line Items]
Ownership interest	50.05%
Property, plant, and equipment	$ 447
Accumulated depreciation	199
Construction work in progress	$ 4
Duke Energy Indiana | Vermillion
Jointly Owned Utility Plant Interests [Line Items]
Ownership interest	62.50%
Property, plant, and equipment	$ 174
Accumulated depreciation	101
Construction work in progress	1
Duke Energy Indiana | Transmission and local facilities
Jointly Owned Utility Plant Interests [Line Items]
Property, plant, and equipment	5,817
Accumulated depreciation	1,508
Construction work in progress	$ 150

Asset Retirement Obligations (R

Asset Retirement Obligations (Recorded on the Balance Sheet) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	$ 13,004	$ 13,318	$ 10,467
Less: Current portion	718	881
Total noncurrent asset retirement obligation	12,286	12,437
Decommissioning of nuclear power facilities
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	6,845
Closure of ash impoundments
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	5,778
Other
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	381
Duke Energy Carolinas
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	5,350	5,734	3,949
Less: Current portion	264	206
Total noncurrent asset retirement obligation	5,086	5,528
Duke Energy Carolinas | Decommissioning of nuclear power facilities
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	2,695
Duke Energy Carolinas | Closure of ash impoundments
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	2,597
Duke Energy Carolinas | Other
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	58
Progress Energy
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	6,149	6,471	5,411
Less: Current portion	283	485
Total noncurrent asset retirement obligation	5,866	5,986
Progress Energy | Decommissioning of nuclear power facilities
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	4,101
Progress Energy | Closure of ash impoundments
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	1,973
Progress Energy | Other
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	75
Duke Energy Progress
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	5,635	5,893	4,820
Less: Current portion	283	485
Total noncurrent asset retirement obligation	5,352	5,408
Duke Energy Progress | Decommissioning of nuclear power facilities
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	3,642
Duke Energy Progress | Closure of ash impoundments
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	1,950
Duke Energy Progress | Other
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	43
Duke Energy Florida
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	514	578	591
Total noncurrent asset retirement obligation	514	578
Duke Energy Florida | Decommissioning of nuclear power facilities
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	459
Duke Energy Florida | Closure of ash impoundments
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	23
Duke Energy Florida | Other
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	32
Duke Energy Ohio
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	111	80	93
Less: Current portion	3	1
Total noncurrent asset retirement obligation	108	79
Duke Energy Ohio | Closure of ash impoundments
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	67
Duke Energy Ohio | Other
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	44
Duke Energy Indiana
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	1,176	832	722
Less: Current portion	168	189
Total noncurrent asset retirement obligation	1,008	643
Duke Energy Indiana | Closure of ash impoundments
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	1,140
Duke Energy Indiana | Other
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	36
Piedmont
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	20	17	$ 19
Total noncurrent asset retirement obligation	20	$ 17
Piedmont | Other
Asset Retirement Obligation [Line Items]
Total asset retirement obligation	$ 20

Asset Retirement Obligations (N

Asset Retirement Obligations (NDTF Information) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
NDTF Information [Abstract]
Annual funding requirement	$ 27
Decommissioning costs	9,105
Legally restricted NDTF investments, fair value	7,726	$ 6,766
Duke Energy Carolinas
NDTF Information [Abstract]
Decommissioning costs	4,365
Legally restricted NDTF investments, fair value	4,381	3,837
Duke Energy Progress
NDTF Information [Abstract]
Annual funding requirement	27
Decommissioning costs	4,181
Legally restricted NDTF investments, fair value	3,345	$ 2,929
Duke Energy Florida
NDTF Information [Abstract]
Decommissioning costs	$ 559

Asset Retirement Obligations _2

Asset Retirement Obligations (Rollforward) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Asset Retirement Obligation [Line Items]
Beginning Balance	$ 13,318	$ 10,467
Accretion expense	542	508
Liabilities settled	(724)	(895)
Liabilities incurred in the current year	22	25
Revisions in estimates of cash flows	(154)	3,213
Ending Balance	13,004	13,318
Duke Energy Carolinas
Asset Retirement Obligation [Line Items]
Beginning Balance	5,734	3,949
Accretion expense	258	235
Liabilities settled	(198)	(329)
Liabilities incurred in the current year		18
Revisions in estimates of cash flows	(444)	1,861
Ending Balance	5,350	5,734
Progress Energy
Asset Retirement Obligation [Line Items]
Beginning Balance	6,471	5,411
Accretion expense	246	252
Liabilities settled	(451)	(499)
Liabilities incurred in the current year	5	7
Revisions in estimates of cash flows	(122)	1,300
Ending Balance	6,149	6,471
Duke Energy Progress
Asset Retirement Obligation [Line Items]
Beginning Balance	5,893	4,820
Accretion expense	225	227
Liabilities settled	(358)	(460)
Revisions in estimates of cash flows	(125)	1,306
Ending Balance	5,635	5,893
Duke Energy Florida
Asset Retirement Obligation [Line Items]
Beginning Balance	578	591
Accretion expense	21	25
Liabilities settled	(93)	(39)
Liabilities incurred in the current year	5	7
Revisions in estimates of cash flows	3	(6)
Ending Balance	514	578
Duke Energy Ohio
Asset Retirement Obligation [Line Items]
Beginning Balance	80	93
Accretion expense	4	3
Liabilities settled	(2)	(12)
Revisions in estimates of cash flows	29	(4)
Ending Balance	111	80
Duke Energy Indiana
Asset Retirement Obligation [Line Items]
Beginning Balance	832	722
Accretion expense	33	28
Liabilities settled	(74)	(54)
Revisions in estimates of cash flows	385	136
Ending Balance	1,176	832
Piedmont
Asset Retirement Obligation [Line Items]
Beginning Balance	17	19
Accretion expense	1	1
Revisions in estimates of cash flows	2	(3)
Ending Balance	$ 20	$ 17

Property, Plant and Equipment_2

Property, Plant and Equipment (Schedule Of Property, Plant and Equipment) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Equipment, estimated useful life, years	15 years	13 years
Land	$ 2,046	$ 2,091
Other buildings and improvements	5,090	4,916
Equipment	2,608	2,313
Construction in process	6,645	6,102
Total property, plant and equipment	155,580	147,654
Generation facilities to be retired, net	29	246
Total net property, plant and equipment	$ 106,782	$ 102,127
Other, estimated useful life, in years	14 years	13 years
Finance leases, gross	$ 832	$ 952
Net property, plant and equipment	797	926
Accumulated amortization of finance leases	12	6
Capitalized Interest Costs [Abstract]
Capitalized interest	112	159	$ 161
Nuclear fuel
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Nuclear fuel	3,284	3,253
Accumulated depreciation and amortization	(1,832)	(1,807)
Consolidated VIEs
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Total property, plant and equipment	6,394	5,747
Accumulated depreciation and amortization	(1,242)	(1,041)
Regulated
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	$ (46,216)	$ (43,419)
Regulated | Electric generation, distribution and transmission
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Equipment, estimated useful life, years	39 years	39 years
Plant - transmission and distribution	$ 117,107	$ 111,739
Regulated | Natural gas transmission and distribution
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Equipment, estimated useful life, years	54 years	54 years
Plant - transmission and distribution	$ 10,799	$ 9,839
Regulated | Other buildings and improvements
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Equipment, estimated useful life, years	36 years	32 years
Other buildings and improvements	$ 2,038	$ 1,810
Nonregulated
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(2,611)	(2,354)
Accumulated amortization of finance leases	$ 23	$ 20
Nonregulated | Electric generation, distribution and transmission
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Equipment, estimated useful life, years	27 years	28 years
Plant - transmission and distribution	$ 5,444	$ 5,103
Nonregulated | Other buildings and improvements
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Equipment, estimated useful life, years	10 years	9 years
Other buildings and improvements	$ 519	$ 488
Duke Energy Carolinas
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Land	536	520
Other buildings and improvements	1,203	1,139
Equipment	620	546
Construction in process	1,645	1,389
Total property, plant and equipment	50,640	48,922
Total net property, plant and equipment	33,187	32,397
Finance leases, gross	335	211
Net property, plant and equipment	312	198
Accumulated amortization of finance leases	23	13
Capitalized Interest Costs [Abstract]
Capitalized interest	28	30	35
Duke Energy Carolinas | Nuclear fuel
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Nuclear fuel	1,837	1,891
Accumulated depreciation and amortization	(1,010)	(1,082)
Duke Energy Carolinas | Regulated
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(17,453)	(16,525)
Duke Energy Carolinas | Regulated | Electric generation, distribution and transmission
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	44,059	42,723
Duke Energy Carolinas | Regulated | Other buildings and improvements
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Other buildings and improvements	740	714
Progress Energy
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Land	908	884
Other buildings and improvements	1,521	1,467
Equipment	759	665
Construction in process	2,013	2,149
Total property, plant and equipment	57,892	55,070
Generation facilities to be retired, net	29	246
Total net property, plant and equipment	39,553	38,157
Net property, plant and equipment	416	443
Accumulated amortization of finance leases	141	143
Capitalized Interest Costs [Abstract]
Capitalized interest	17	31	51
Progress Energy | Nuclear fuel
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Nuclear fuel	1,447	1,362
Accumulated depreciation and amortization	(822)	(725)
Progress Energy | Regulated
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(18,368)	(17,159)
Progress Energy | Regulated | Electric generation, distribution and transmission
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	50,785	48,142
Progress Energy | Regulated | Other buildings and improvements
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Other buildings and improvements	459	401
Duke Energy Progress
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Land	463	449
Other buildings and improvements	1,070	1,046
Equipment	498	452
Construction in process	709	1,114
Total property, plant and equipment	35,759	34,603
Generation facilities to be retired, net	29	246
Total net property, plant and equipment	22,987	22,934
Net property, plant and equipment	297	308
Accumulated amortization of finance leases	24	17
Capitalized Interest Costs [Abstract]
Capitalized interest	12	28	26
Duke Energy Progress | Nuclear fuel
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Nuclear fuel	1,447	1,362
Accumulated depreciation and amortization	(822)	(725)
Duke Energy Progress | Regulated
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(12,801)	(11,915)
Duke Energy Progress | Regulated | Electric generation, distribution and transmission
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	31,375	30,018
Duke Energy Progress | Regulated | Other buildings and improvements
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Other buildings and improvements	197	162
Duke Energy Florida
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Land	445	435
Other buildings and improvements	441	411
Equipment	261	213
Construction in process	1,304	1,035
Total property, plant and equipment	22,123	20,457
Total net property, plant and equipment	16,563	15,221
Net property, plant and equipment	119	135
Accumulated amortization of finance leases	117	126
Capitalized Interest Costs [Abstract]
Capitalized interest	5	3	25
Duke Energy Florida | Regulated
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(5,560)	(5,236)
Duke Energy Florida | Regulated | Electric generation, distribution and transmission
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	19,410	18,124
Duke Energy Florida | Regulated | Other buildings and improvements
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Other buildings and improvements	262	239
Duke Energy Ohio
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Land	171	150
Other buildings and improvements	294	269
Equipment	385	319
Construction in process	407	504
Total property, plant and equipment	11,022	10,241
Total net property, plant and equipment	8,009	7,398
Capitalized Interest Costs [Abstract]
Capitalized interest	26	22	17
Duke Energy Ohio | Regulated
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(3,013)	(2,843)
Duke Energy Ohio | Regulated | Electric generation, distribution and transmission
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	6,255	5,838
Duke Energy Ohio | Regulated | Natural gas transmission and distribution
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	3,136	2,892
Duke Energy Ohio | Regulated | Other buildings and improvements
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Other buildings and improvements	374	269
Duke Energy Indiana
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Land	118	117
Other buildings and improvements	309	292
Equipment	238	205
Construction in process	409	381
Total property, plant and equipment	17,382	16,305
Total net property, plant and equipment	11,721	11,072
Finance leases, gross	10	10
Net property, plant and equipment	7	7
Accumulated amortization of finance leases	3	3
Capitalized Interest Costs [Abstract]
Capitalized interest	10	26	27
Duke Energy Indiana | Regulated
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(5,661)	(5,233)
Duke Energy Indiana | Regulated | Electric generation, distribution and transmission
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	16,008	15,032
Duke Energy Indiana | Regulated | Other buildings and improvements
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Other buildings and improvements	300	278
Piedmont
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Land	279	388
Other buildings and improvements	324	304
Equipment	122	128
Construction in process	581	531
Total property, plant and equipment	9,134	8,446
Total net property, plant and equipment	7,385	6,765
Capitalized Interest Costs [Abstract]
Capitalized interest	8	26	$ 17
Piedmont | Regulated
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(1,749)	(1,681)
Piedmont | Regulated | Natural gas transmission and distribution
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	7,663	6,947
Piedmont | Regulated | Other buildings and improvements
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Other buildings and improvements	$ 165	$ 148

Property, Plant and Equipment_3

Property, Plant and Equipment (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Net property, plant and equipment	$ 106,782	$ 102,127
Renewable merchant plants
Property, Plant and Equipment [Line Items]
Net property, plant and equipment	$ 210
Ownership interest	51.00%

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets (Goodwill By Reportable Operating Segment) (Details) - USD ($)	Aug. 31, 2020	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2020	Dec. 31, 2019
Goodwill [Line Items]
Goodwill, gross				$ 19,425,000,000	$ 19,425,000,000
Accumulated impairment charges				(122,000,000)	(122,000,000)
Goodwill, net				19,303,000,000	19,303,000,000
Impairment charges	$ 0
Electric Utilities and Infrastructure
Goodwill [Line Items]
Goodwill, gross				17,379,000,000	17,379,000,000
Goodwill, net				17,379,000,000	17,379,000,000
Gas Utilities and Infrastructure
Goodwill [Line Items]
Goodwill, gross				1,924,000,000	1,924,000,000
Goodwill, net				1,924,000,000	1,924,000,000
Commercial Renewables
Goodwill [Line Items]
Goodwill, gross				122,000,000	122,000,000
Accumulated impairment charges				(122,000,000)	(122,000,000)
Impairment charges		$ 93,000,000	$ 29,000,000
Duke Energy Ohio
Goodwill [Line Items]
Accumulated impairment charges				(216,000,000)	(216,000,000)
Goodwill, net				920,000,000	920,000,000
Duke Energy Ohio | Electric Utilities and Infrastructure
Goodwill [Line Items]
Goodwill, net				596,000,000	596,000,000
Duke Energy Ohio | Gas Utilities and Infrastructure
Goodwill [Line Items]
Goodwill, net				324,000,000	324,000,000
Progress Energy
Goodwill [Line Items]
Goodwill, net				3,655,000,000	3,655,000,000
Progress Energy | Electric Utilities and Infrastructure
Goodwill [Line Items]
Accumulated impairment charges				0
Piedmont
Goodwill [Line Items]
Goodwill, net				49,000,000	$ 49,000,000
Piedmont | Gas Utilities and Infrastructure
Goodwill [Line Items]
Accumulated impairment charges				$ 0

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets (Narrative) (Details) - USD ($)	Aug. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Goodwill [Line Items]
Goodwill		$ 19,303,000,000	$ 19,303,000,000
Goodwill accumulated impairment loss		122,000,000	122,000,000
Impairment charges	$ 0
Electric Utilities and Infrastructure
Goodwill [Line Items]
Goodwill		17,379,000,000	17,379,000,000
Gas Utilities and Infrastructure
Goodwill [Line Items]
Goodwill		1,924,000,000	1,924,000,000
Duke Energy Ohio
Goodwill [Line Items]
Goodwill		920,000,000	920,000,000
Goodwill accumulated impairment loss		216,000,000	216,000,000
Duke Energy Ohio | Electric Utilities and Infrastructure
Goodwill [Line Items]
Goodwill		596,000,000	596,000,000
Duke Energy Ohio | Gas Utilities and Infrastructure
Goodwill [Line Items]
Goodwill		324,000,000	324,000,000
Progress Energy
Goodwill [Line Items]
Goodwill		3,655,000,000	3,655,000,000
Progress Energy | Electric Utilities and Infrastructure
Goodwill [Line Items]
Goodwill accumulated impairment loss		0
Piedmont
Goodwill [Line Items]
Goodwill		49,000,000	$ 49,000,000
Piedmont | Gas Utilities and Infrastructure
Goodwill [Line Items]
Goodwill accumulated impairment loss		$ 0

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets (Schedule of Intangible Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	$ 355	$ 305
Accumulated amortization	(60)	(56)
Total intangible assets, net	295	249
Emission allowances
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	8	18
Renewable energy certificates
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	196	172
Natural gas, coal and power contracts
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	24	24
Accumulated amortization	(23)	(21)
Renewable operating and development projects
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	107	89
Accumulated amortization	(34)	(34)
Other
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	20	2
Accumulated amortization	(3)	(1)
Duke Energy Carolinas
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	65	53
Total intangible assets, net	65	53
Duke Energy Carolinas | Renewable energy certificates
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	65	53
Progress Energy
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	135	123
Total intangible assets, net	135	123
Progress Energy | Emission allowances
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	5	5
Progress Energy | Renewable energy certificates
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	130	118
Duke Energy Progress
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	132	120
Total intangible assets, net	132	120
Duke Energy Progress | Emission allowances
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	2	2
Duke Energy Progress | Renewable energy certificates
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	130	118
Duke Energy Florida
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	3	3
Total intangible assets, net	3	3
Duke Energy Florida | Emission allowances
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	3	3
Duke Energy Ohio
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	1	1
Total intangible assets, net	1	1
Duke Energy Ohio | Renewable energy certificates
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	1	1
Duke Energy Indiana
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	26	36
Accumulated amortization	(23)	(21)
Total intangible assets, net	3	15
Duke Energy Indiana | Emission allowances
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	2	12
Duke Energy Indiana | Natural gas, coal and power contracts
Finite-Lived Intangible Assets, Net [Abstract]
Gross carrying amount	24	24
Accumulated amortization	$ (23)	$ (21)

Investments in Unconsolidated_3

Investments in Unconsolidated Affiliates (Investments in Equity Method Unconsolidated Affiliates) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Investments In Unconsolidated Affiliates [Line Items]
Investments	$ 961	$ 1,936	$ 1,409
Equity in (losses) earnings of unconsolidated affiliates	(2,005)	162	83
Electric Utilities and Infrastructure
Investments In Unconsolidated Affiliates [Line Items]
Investments	105	122	97
Equity in (losses) earnings of unconsolidated affiliates	(1)	9	6
Gas Utilities and Infrastructure
Investments In Unconsolidated Affiliates [Line Items]
Investments	215	1,388	1,003
Equity in (losses) earnings of unconsolidated affiliates	(2,017)	114	27
Commercial Renewables
Investments In Unconsolidated Affiliates [Line Items]
Investments	534	314	201
Equity in (losses) earnings of unconsolidated affiliates		(4)	(1)
Other
Investments In Unconsolidated Affiliates [Line Items]
Investments	107	112	108
Equity in (losses) earnings of unconsolidated affiliates	$ 13	$ 43	$ 51

Investments in Unconsolidated_4

Investments in Unconsolidated Affiliates (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)assetMW	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Jun. 30, 2019
Investments In Unconsolidated Affiliates [Line Items]
Distributions from equity investments	$ 37	$ 55	$ 108
Distributions from equity investments, return of capital	$ 133	11	137
Electric Utilities and Infrastructure | DATC
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest	50.00%
Electric Utilities and Infrastructure | Pioneer
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest	50.00%
Commercial Renewables | Non-consolidated VIEs
Investments In Unconsolidated Affiliates [Line Items]
Number of cell projects | asset	70
Capacity of assets | MW	43
Commercial Renewables | DS Cornerstone
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest	26.00%			50.00%
Other | NMC
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest	17.50%
Board representation and voting rights, ownership percentage	25.00%
Piedmont
Investments In Unconsolidated Affiliates [Line Items]
Distributions from equity investments	$ 2	1	1
Distributions from equity investments, return of capital	$ 2	$ 4	$ 3

Investments in Unconsolidated_5

Investments in Unconsolidated Affiliates (Gas Utilities and Infrastructure Investments) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2020
Investments In Unconsolidated Affiliates [Line Items]
Investments in equity method unconsolidated affiliates	$ 1,936	$ 1,409	$ 961
Gas Utilities and Infrastructure
Investments In Unconsolidated Affiliates [Line Items]
Investments in equity method unconsolidated affiliates	1,388	1,003	$ 215
Gas Utilities and Infrastructure | ACP
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest			47.00%
Investments in equity method unconsolidated affiliates	1,179
Gas Utilities and Infrastructure | Sabal Trail
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest			7.50%
Investments in equity method unconsolidated affiliates	121		$ 120
Gas Utilities and Infrastructure | Other
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest			29.68%
Investments in equity method unconsolidated affiliates			$ 3
Gas Utilities and Infrastructure | Constitution
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest			24.00%
Impairment losses	25	$ 55
Piedmont and Duke | Gas Utilities and Infrastructure | Cardinal
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest			21.49%
Investments in equity method unconsolidated affiliates	9		$ 9
Piedmont and Duke | Gas Utilities and Infrastructure | Pine Needle
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest			45.00%
Investments in equity method unconsolidated affiliates	28		$ 27
Piedmont and Duke | Gas Utilities and Infrastructure | Hardy Storage
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest			50.00%
Investments in equity method unconsolidated affiliates	$ 51		$ 56

Investments in Unconsolidated_6

Investments in Unconsolidated Affiliates (Significant Subsidiaries) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Investments In Unconsolidated Affiliates [Line Items]
Current assets	$ 8,682	$ 9,163
Noncurrent assets	46,924	47,548
Current liabilities	16,305	14,752
Noncurrent liabilities	41,274	41,150
Membership interests	1,220	1,129
Operating loss	4,553	5,709	$ 4,685
Net income (loss)	1,082	3,571	2,644
Net (loss) income attributable to Duke Energy	1,377	3,748	2,666
Atlantic Coast Pipeline (ACP) | Equity Method Investment, Nonconsolidated Investee or Group of Investees
Investments In Unconsolidated Affiliates [Line Items]
Current assets	43	17
Noncurrent assets	93	4,091
Current liabilities	1,965	37
Noncurrent liabilities	167	1,760
Membership interests	(1,996)	2,311
Net revenues	0
Operating loss	(4,612)	(5)	(6)
Net income (loss)	(4,512)	246	138
Net (loss) income attributable to Duke Energy	$ (2,121)	$ 116	$ 65

Related Party Transactions (Oth

Related Party Transactions (Other Revenue and Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Duke Energy Carolinas | Corporate governance and shared service expenses | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	$ 753	$ 841	$ 985
Duke Energy Carolinas | Indemnification coverages | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	20	20	22
Duke Energy Carolinas | Joint Dispatch Agreement (JDA) revenue | Duke Energy Progress
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	114	186	207
Related party transaction, other revenues from transactions with related party	25	60	84
Duke Energy Carolinas | Intercompany natural gas transactions | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	15	15	15
Progress Energy | Corporate governance and shared service expenses | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	715	778	906
Progress Energy | Indemnification coverages | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	36	37	34
Progress Energy | Joint Dispatch Agreement (JDA) revenue | Duke Energy Carolinas
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	25	60	84
Related party transaction, other revenues from transactions with related party	114	186	207
Progress Energy | Intercompany natural gas transactions | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	75	76	78
Duke Energy Progress | Corporate governance and shared service expenses | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	420	462	577
Duke Energy Progress | Indemnification coverages | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	17	15	13
Duke Energy Progress | Joint Dispatch Agreement (JDA) revenue | Duke Energy Carolinas
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	25	60	84
Related party transaction, other revenues from transactions with related party	114	186	207
Duke Energy Progress | Intercompany natural gas transactions | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	75	76	78
Duke Energy Florida | Corporate governance and shared service expenses | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	295	316	329
Duke Energy Florida | Indemnification coverages | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	19	22	21
Duke Energy Ohio | Corporate governance and shared service expenses | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	326	354	374
Duke Energy Ohio | Indemnification coverages | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	4	4	5
Duke Energy Indiana | Corporate governance and shared service expenses | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	401	412	405
Duke Energy Indiana | Indemnification coverages | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	8	7	7
Piedmont | Corporate governance and shared service expenses | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	140	138	170
Piedmont | Indemnification coverages | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	3	3	2
Piedmont | Intercompany natural gas transactions | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, other revenues from transactions with related party	90	91	93
Piedmont | Natural gas storage and transportation costs | Affiliated entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	$ 23	$ 23	$ 25

Related Party Transactions (Int

Related Party Transactions (Intercompany Income Taxes) (Details) - Affiliated entity - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Duke Energy Carolinas
Related Party Transaction [Line Items]
Intercompany income tax payable	$ 31	$ 5
Progress Energy
Related Party Transaction [Line Items]
Intercompany income tax receivable		125
Intercompany income tax payable	33
Duke Energy Progress
Related Party Transaction [Line Items]
Intercompany income tax receivable		28
Intercompany income tax payable	46
Duke Energy Florida
Related Party Transaction [Line Items]
Intercompany income tax payable	35	2
Duke Energy Ohio
Related Party Transaction [Line Items]
Intercompany income tax receivable		9
Intercompany income tax payable	2
Duke Energy Indiana
Related Party Transaction [Line Items]
Intercompany income tax receivable	9	28
Piedmont
Related Party Transaction [Line Items]
Intercompany income tax receivable	$ 10	$ 13

Derivatives and Hedging (Notion

Derivatives and Hedging (Notional Amounts of Derivative Instruments) (Details) Mcf in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)GWhMcf	Dec. 31, 2019USD ($)GWhMcf
Interest Rate Contracts
Derivative [Line Items]
Notional Amount	$ 1,809	$ 2,270
Interest Rate Contracts | Designated contracts | Cash flow hedges
Derivative [Line Items]
Notional Amount	632	993
Interest Rate Contracts | Undesignated contracts
Derivative [Line Items]
Notional Amount	$ 1,177	$ 1,277
Commodity contracts | Electricity (GWh)(a)
Derivative [Line Items]
Notional amount, energy measure, in gigawatt-hours | GWh	35,409	15,858
Commodity contracts | Electricity (GWh)(a) | Cash flow hedges
Derivative [Line Items]
Notional amount, energy measure, in gigawatt-hours | GWh	22,048
Commodity contracts | Natural gas (millions of Dth)
Derivative [Line Items]
Notional amount, volume in millions of decatherms | Mcf	678	704
Consolidated VIEs | Interest Rate Contracts | Designated contracts | Cash flow hedges
Derivative [Line Items]
Notional Amount	$ 632	$ 693
Duke Energy Carolinas | Interest Rate Contracts
Derivative [Line Items]
Notional Amount	400	450
Duke Energy Carolinas | Interest Rate Contracts | Undesignated contracts
Derivative [Line Items]
Notional Amount	$ 400	$ 450
Duke Energy Carolinas | Commodity contracts | Natural gas (millions of Dth)
Derivative [Line Items]
Notional amount, volume in millions of decatherms | Mcf	145	130
Progress Energy | Interest Rate Contracts
Derivative [Line Items]
Notional Amount	$ 750	$ 800
Progress Energy | Interest Rate Contracts | Undesignated contracts
Derivative [Line Items]
Notional Amount	$ 750	$ 800
Progress Energy | Commodity contracts | Natural gas (millions of Dth)
Derivative [Line Items]
Notional amount, volume in millions of decatherms | Mcf	158	160
Duke Energy Progress | Interest Rate Contracts
Derivative [Line Items]
Notional Amount	$ 750	$ 250
Duke Energy Progress | Interest Rate Contracts | Undesignated contracts
Derivative [Line Items]
Notional Amount	$ 750	$ 250
Duke Energy Progress | Commodity contracts | Natural gas (millions of Dth)
Derivative [Line Items]
Notional amount, volume in millions of decatherms | Mcf	158	160
Duke Energy Florida | Interest Rate Contracts
Derivative [Line Items]
Notional Amount		$ 550
Duke Energy Florida | Interest Rate Contracts | Undesignated contracts
Derivative [Line Items]
Notional Amount		550
Duke Energy Ohio | Interest Rate Contracts
Derivative [Line Items]
Notional Amount	$ 27	27
Duke Energy Ohio | Interest Rate Contracts | Undesignated contracts
Derivative [Line Items]
Notional Amount	$ 27	$ 27
Duke Energy Ohio | Commodity contracts | Electricity (GWh)(a)
Derivative [Line Items]
Notional amount, energy measure, in gigawatt-hours | GWh	2,559	1,887
Duke Energy Indiana | Commodity contracts | Electricity (GWh)(a)
Derivative [Line Items]
Notional amount, energy measure, in gigawatt-hours | GWh	10,802	13,971
Duke Energy Indiana | Commodity contracts | Natural gas (millions of Dth)
Derivative [Line Items]
Notional amount, volume in millions of decatherms | Mcf	2	3
Piedmont | Commodity contracts | Natural gas (millions of Dth)
Derivative [Line Items]
Notional amount, volume in millions of decatherms | Mcf	373	411

Derivatives and Hedging (Locati

Derivatives and Hedging (Location and Fair Value Amounts of Derivatives Reflected in the Consolidated Balance Sheets) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	$ 61	$ 25
Location and fair value amounts of derivatives liabilities	324	300
Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	48	24
Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	13	1
Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	64	118
Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	260	182
Commodity Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	43	18
Location and fair value amounts of derivatives liabilities	251	223
Interest Rate Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	18	6
Location and fair value amounts of derivatives liabilities	73	53
Equity Securities Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets		1
Location and fair value amounts of derivatives liabilities		24
Designated as Hedging Instruments | Commodity Contracts | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	14
Designated as Hedging Instruments | Commodity Contracts | Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	70
Designated as Hedging Instruments | Interest Rate Contracts | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	15	19
Designated as Hedging Instruments | Interest Rate Contracts | Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	48	21
Not Designated as Hedging Instruments | Commodity Contracts | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	30	17
Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	13	1
Not Designated as Hedging Instruments | Commodity Contracts | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	30	67
Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	137	156
Not Designated as Hedging Instruments | Interest Rate Contracts | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	18	6
Not Designated as Hedging Instruments | Interest Rate Contracts | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	5	8
Not Designated as Hedging Instruments | Interest Rate Contracts | Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	5	5
Not Designated as Hedging Instruments | Equity Securities Contracts | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets		1
Not Designated as Hedging Instruments | Equity Securities Contracts | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities		24
Duke Energy Carolinas
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	20
Location and fair value amounts of derivatives liabilities	20	49
Duke Energy Carolinas | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	14
Duke Energy Carolinas | Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	6
Duke Energy Carolinas | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	17	39
Duke Energy Carolinas | Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	3	10
Duke Energy Carolinas | Commodity Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	20
Location and fair value amounts of derivatives liabilities	16	43
Duke Energy Carolinas | Interest Rate Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	0
Location and fair value amounts of derivatives liabilities	4	6
Duke Energy Carolinas | Not Designated as Hedging Instruments | Commodity Contracts | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	14
Duke Energy Carolinas | Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	6
Duke Energy Carolinas | Not Designated as Hedging Instruments | Commodity Contracts | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	13	33
Duke Energy Carolinas | Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	3	10
Duke Energy Carolinas | Not Designated as Hedging Instruments | Interest Rate Contracts | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	0
Duke Energy Carolinas | Not Designated as Hedging Instruments | Interest Rate Contracts | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	4	6
Progress Energy
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	33	7
Location and fair value amounts of derivatives liabilities	29	88
Progress Energy | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	27	7
Progress Energy | Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	6
Progress Energy | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	2	51
Progress Energy | Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	27	37
Progress Energy | Commodity Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	15
Location and fair value amounts of derivatives liabilities	29	63
Progress Energy | Interest Rate Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	18	6
Location and fair value amounts of derivatives liabilities		1
Progress Energy | Equity Securities Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets		1
Location and fair value amounts of derivatives liabilities		24
Progress Energy | Not Designated as Hedging Instruments | Commodity Contracts | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	9
Progress Energy | Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	6
Progress Energy | Not Designated as Hedging Instruments | Commodity Contracts | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	2	26
Progress Energy | Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	27	37
Progress Energy | Not Designated as Hedging Instruments | Interest Rate Contracts | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	18	6
Progress Energy | Not Designated as Hedging Instruments | Interest Rate Contracts | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities		1
Progress Energy | Not Designated as Hedging Instruments | Equity Securities Contracts | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets		1
Progress Energy | Not Designated as Hedging Instruments | Equity Securities Contracts | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities		24
Duke Energy Progress
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	33
Location and fair value amounts of derivatives liabilities	14	49
Duke Energy Progress | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	27
Duke Energy Progress | Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	6
Duke Energy Progress | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	2	27
Duke Energy Progress | Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	12	22
Duke Energy Progress | Commodity Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	15
Location and fair value amounts of derivatives liabilities	14	48
Duke Energy Progress | Interest Rate Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	18
Location and fair value amounts of derivatives liabilities		1
Duke Energy Progress | Not Designated as Hedging Instruments | Commodity Contracts | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	9
Duke Energy Progress | Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	6
Duke Energy Progress | Not Designated as Hedging Instruments | Commodity Contracts | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	2	26
Duke Energy Progress | Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	12	22
Duke Energy Progress | Not Designated as Hedging Instruments | Interest Rate Contracts | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	18
Duke Energy Progress | Not Designated as Hedging Instruments | Interest Rate Contracts | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities		1
Duke Energy Florida
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets		7
Location and fair value amounts of derivatives liabilities		24
Duke Energy Florida | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets		7
Duke Energy Florida | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	0	24
Duke Energy Florida | Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	0
Duke Energy Florida | Interest Rate Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets		6
Duke Energy Florida | Equity Securities Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets		1
Location and fair value amounts of derivatives liabilities		24
Duke Energy Florida | Not Designated as Hedging Instruments | Interest Rate Contracts | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets		6
Duke Energy Florida | Not Designated as Hedging Instruments | Equity Securities Contracts | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets		1
Duke Energy Florida | Not Designated as Hedging Instruments | Equity Securities Contracts | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities		24
Duke Energy Ohio
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	1	4
Location and fair value amounts of derivatives liabilities	6	6
Duke Energy Ohio | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	1	3
Duke Energy Ohio | Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets		1
Duke Energy Ohio | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	1	1
Duke Energy Ohio | Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	5	5
Duke Energy Ohio | Commodity Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	1	4
Duke Energy Ohio | Interest Rate Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	6	6
Duke Energy Ohio | Not Designated as Hedging Instruments | Commodity Contracts | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	1	3
Duke Energy Ohio | Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets		1
Duke Energy Ohio | Not Designated as Hedging Instruments | Interest Rate Contracts | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	1	1
Duke Energy Ohio | Not Designated as Hedging Instruments | Interest Rate Contracts | Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	5	5
Duke Energy Indiana
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	6	13
Location and fair value amounts of derivatives liabilities	1	1
Duke Energy Indiana | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	6	13
Duke Energy Indiana | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	1	1
Duke Energy Indiana | Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	0
Duke Energy Indiana | Commodity Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	6	13
Location and fair value amounts of derivatives liabilities	1	1
Duke Energy Indiana | Not Designated as Hedging Instruments | Commodity Contracts | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	6	13
Duke Energy Indiana | Not Designated as Hedging Instruments | Commodity Contracts | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	1	1
Piedmont
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	1	1
Location and fair value amounts of derivatives liabilities	122	117
Piedmont | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	1	1
Piedmont | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	15	7
Piedmont | Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	107	110
Piedmont | Commodity Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	1	1
Location and fair value amounts of derivatives liabilities	122	117
Piedmont | Not Designated as Hedging Instruments | Commodity Contracts | Current Assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives assets	1	1
Piedmont | Not Designated as Hedging Instruments | Commodity Contracts | Current Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	15	7
Piedmont | Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives liabilities	$ 107	$ 110

Derivatives and Hedging (Schedu

Derivatives and Hedging (Schedule of Offsetting Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Offsetting Assets [Line Items]
Gross amounts recognized	$ 61	$ 25
Net amounts presented on Balance Sheets	61	25
Current Assets
Offsetting Assets [Line Items]
Gross amounts recognized	48	24
Gross amounts offset	(3)	(1)
Net amounts presented on Balance Sheets	45	23
Noncurrent assets
Offsetting Assets [Line Items]
Gross amounts recognized	13	1
Gross amounts offset	(5)
Net amounts presented on Balance Sheets	8	1
Duke Energy Carolinas
Offsetting Assets [Line Items]
Gross amounts recognized	20
Duke Energy Carolinas | Current Assets
Offsetting Assets [Line Items]
Gross amounts recognized	14
Gross amounts offset	(2)
Net amounts presented on Balance Sheets	12
Duke Energy Carolinas | Noncurrent assets
Offsetting Assets [Line Items]
Gross amounts recognized	6
Gross amounts offset	(1)
Net amounts presented on Balance Sheets	5
Progress Energy
Offsetting Assets [Line Items]
Gross amounts recognized	33	7
Net amounts presented on Balance Sheets	33	7
Progress Energy | Current Assets
Offsetting Assets [Line Items]
Gross amounts recognized	27	7
Gross amounts offset	(2)	(1)
Net amounts presented on Balance Sheets	25	6
Progress Energy | Noncurrent assets
Offsetting Assets [Line Items]
Gross amounts recognized	6
Gross amounts offset	(4)
Net amounts presented on Balance Sheets	2
Duke Energy Progress
Offsetting Assets [Line Items]
Gross amounts recognized	33
Net amounts presented on Balance Sheets	33
Duke Energy Progress | Current Assets
Offsetting Assets [Line Items]
Gross amounts recognized	27
Gross amounts offset	(2)
Net amounts presented on Balance Sheets	25
Duke Energy Progress | Noncurrent assets
Offsetting Assets [Line Items]
Gross amounts recognized	6
Gross amounts offset	(4)
Net amounts presented on Balance Sheets	2
Duke Energy Florida
Offsetting Assets [Line Items]
Gross amounts recognized		7
Net amounts presented on Balance Sheets		7
Duke Energy Florida | Current Assets
Offsetting Assets [Line Items]
Gross amounts recognized		7
Gross amounts offset		(1)
Net amounts presented on Balance Sheets		6
Duke Energy Ohio
Offsetting Assets [Line Items]
Gross amounts recognized	1	4
Duke Energy Ohio | Current Assets
Offsetting Assets [Line Items]
Gross amounts recognized	1	3
Net amounts presented on Balance Sheets	1	3
Duke Energy Ohio | Noncurrent assets
Offsetting Assets [Line Items]
Gross amounts recognized		1
Net amounts presented on Balance Sheets		1
Duke Energy Indiana
Offsetting Assets [Line Items]
Gross amounts recognized	6	13
Net amounts presented on Balance Sheets	6	13
Duke Energy Indiana | Current Assets
Offsetting Assets [Line Items]
Gross amounts recognized	6	13
Net amounts presented on Balance Sheets	6	13
Piedmont
Offsetting Assets [Line Items]
Gross amounts recognized	1	1
Net amounts presented on Balance Sheets	1	1
Piedmont | Current Assets
Offsetting Assets [Line Items]
Gross amounts recognized	1	1
Net amounts presented on Balance Sheets	$ 1	$ 1

Derivatives and Hedging (Sche_2

Derivatives and Hedging (Schedule of Offsetting Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Offsetting Liabilities [Line Items]
Gross amounts recognized	$ 324	$ 300
Net amounts presented on Balance Sheets	324	277
Current Liabilities
Offsetting Liabilities [Line Items]
Gross amounts recognized	64	118
Gross amounts offset	(3)	(24)
Net amounts presented on Balance Sheets	61	94
Noncurrent Liabilities
Offsetting Liabilities [Line Items]
Gross amounts recognized	260	182
Gross amounts offset	(5)
Net amounts presented on Balance Sheets	255	182
Duke Energy Carolinas
Offsetting Liabilities [Line Items]
Gross amounts recognized	20	49
Net amounts presented on Balance Sheets	20	49
Duke Energy Carolinas | Current Liabilities
Offsetting Liabilities [Line Items]
Gross amounts recognized	17	39
Gross amounts offset	(2)
Net amounts presented on Balance Sheets	15	39
Duke Energy Carolinas | Noncurrent Liabilities
Offsetting Liabilities [Line Items]
Gross amounts recognized	3	10
Gross amounts offset	(1)
Net amounts presented on Balance Sheets	2	10
Progress Energy
Offsetting Liabilities [Line Items]
Gross amounts recognized	29	88
Net amounts presented on Balance Sheets	29	65
Progress Energy | Current Liabilities
Offsetting Liabilities [Line Items]
Gross amounts recognized	2	51
Gross amounts offset	(2)	(24)
Net amounts presented on Balance Sheets		27
Progress Energy | Noncurrent Liabilities
Offsetting Liabilities [Line Items]
Gross amounts recognized	27	37
Gross amounts offset	(4)
Net amounts presented on Balance Sheets	23	37
Duke Energy Progress
Offsetting Liabilities [Line Items]
Gross amounts recognized	14	49
Net amounts presented on Balance Sheets	14	49
Duke Energy Progress | Current Liabilities
Offsetting Liabilities [Line Items]
Gross amounts recognized	2	27
Gross amounts offset	(2)
Net amounts presented on Balance Sheets		27
Duke Energy Progress | Noncurrent Liabilities
Offsetting Liabilities [Line Items]
Gross amounts recognized	12	22
Gross amounts offset	(4)
Net amounts presented on Balance Sheets	8	22
Duke Energy Florida
Offsetting Liabilities [Line Items]
Gross amounts recognized		24
Net amounts presented on Balance Sheets		1
Duke Energy Florida | Current Liabilities
Offsetting Liabilities [Line Items]
Gross amounts recognized	0	24
Gross amounts offset	0	(24)
Net amounts presented on Balance Sheets	0
Duke Energy Florida | Noncurrent Liabilities
Offsetting Liabilities [Line Items]
Gross amounts recognized	0
Gross amounts offset	0
Net amounts presented on Balance Sheets	0
Duke Energy Ohio
Offsetting Liabilities [Line Items]
Gross amounts recognized	6	6
Duke Energy Ohio | Current Liabilities
Offsetting Liabilities [Line Items]
Gross amounts recognized	1	1
Gross amounts offset	0
Net amounts presented on Balance Sheets	1	1
Duke Energy Ohio | Noncurrent Liabilities
Offsetting Liabilities [Line Items]
Gross amounts recognized	5	5
Gross amounts offset	0
Net amounts presented on Balance Sheets	5	5
Duke Energy Indiana
Offsetting Liabilities [Line Items]
Gross amounts recognized	1	1
Net amounts presented on Balance Sheets	1	1
Duke Energy Indiana | Current Liabilities
Offsetting Liabilities [Line Items]
Gross amounts recognized	1	1
Gross amounts offset	0
Net amounts presented on Balance Sheets	1	1
Duke Energy Indiana | Noncurrent Liabilities
Offsetting Liabilities [Line Items]
Gross amounts recognized	0
Gross amounts offset	0
Net amounts presented on Balance Sheets	0
Piedmont
Offsetting Liabilities [Line Items]
Gross amounts recognized	122	117
Net amounts presented on Balance Sheets	122	117
Piedmont | Current Liabilities
Offsetting Liabilities [Line Items]
Gross amounts recognized	15	7
Gross amounts offset	0
Net amounts presented on Balance Sheets	15	7
Piedmont | Noncurrent Liabilities
Offsetting Liabilities [Line Items]
Gross amounts recognized	107	110
Gross amounts offset	0
Net amounts presented on Balance Sheets	$ 107	$ 110

Derivatives and Hedging (Deriva

Derivatives and Hedging (Derivative Instruments That Contain Credit-Risk Related Contingent Features and Cash Collateral) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Information Regarding Derivative Instruments That Contain Credit-Risk Related Contingent Features
Aggregate fair value of derivatives in a net liability position	$ 24	$ 79
Fair value of collateral already posted	0	0
Additional cash collateral or letters of credit in the event credit-risk-related contingent features were triggered	24	79
Duke Energy Carolinas
Schedule Of Information Regarding Derivative Instruments That Contain Credit-Risk Related Contingent Features
Aggregate fair value of derivatives in a net liability position	9	35
Fair value of collateral already posted	0	0
Additional cash collateral or letters of credit in the event credit-risk-related contingent features were triggered	9	35
Progress Energy
Schedule Of Information Regarding Derivative Instruments That Contain Credit-Risk Related Contingent Features
Aggregate fair value of derivatives in a net liability position	14	44
Fair value of collateral already posted	0	0
Additional cash collateral or letters of credit in the event credit-risk-related contingent features were triggered	14	44
Duke Energy Progress
Schedule Of Information Regarding Derivative Instruments That Contain Credit-Risk Related Contingent Features
Aggregate fair value of derivatives in a net liability position	14	44
Fair value of collateral already posted	0	0
Additional cash collateral or letters of credit in the event credit-risk-related contingent features were triggered	$ 14	$ 44

Investments in Debt and Equit_3

Investments in Debt and Equity Securities (Estimated Fair Value of Investments in Debt and Equity Securities) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale
Estimated Fair Value	$ 3,002
Total Investments
Unrealized Holding Gains	4,387	$ 3,675
Unrealized Holding Losses	55	57
Estimated Fair Value	9,687	8,562
NDTF
Equity Securities, FV-NI
Gross Unrealized Holding Gains	4,138	3,523
Gross Unrealized Holding Losses	54	55
Estimated Fair Value	6,235	5,661
Debt Securities, Available-for-sale
Estimated Fair Value	2,717	2,368
Total Investments
Unrealized Holding Gains	4,295	3,609
Unrealized Holding Losses	55	57
Estimated Fair Value	9,129	8,130
NDTF | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	177	101
NDTF | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	76	37
Gross Unrealized Holding Losses	1	1
Estimated Fair Value	806	603
NDTF | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	22	13
Gross Unrealized Holding Losses	0	0
Estimated Fair Value	370	368
NDTF | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	51	33
Gross Unrealized Holding Losses		1
Estimated Fair Value	1,361	1,256
NDTF | Other debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	8	3
Gross Unrealized Holding Losses	0	0
Estimated Fair Value	180	141
Other Investments
Equity Securities, FV-NI
Gross Unrealized Holding Gains	79	57
Gross Unrealized Holding Losses	0	0
Estimated Fair Value	146	122
Debt Securities, Available-for-sale
Estimated Fair Value	285	258
Total Investments
Unrealized Holding Gains	92	66
Unrealized Holding Losses	0	0
Estimated Fair Value	558	432
Other Investments | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	127	52
Other Investments | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	8	3
Gross Unrealized Holding Losses	0	0
Estimated Fair Value	110	67
Other Investments | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	5	4
Gross Unrealized Holding Losses	0	0
Estimated Fair Value	86	94
Other Investments | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	0	2
Gross Unrealized Holding Losses	0	0
Estimated Fair Value	42	41
Other Investments | Other debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	0	0
Gross Unrealized Holding Losses	0	0
Estimated Fair Value	47	56
Duke Energy Carolinas
Equity Securities, FV-NI
Estimated Fair Value		3,154
Debt Securities, Available-for-sale
Estimated Fair Value	1,250
Duke Energy Carolinas | NDTF
Equity Securities, FV-NI
Gross Unrealized Holding Gains	2,442	1,914
Gross Unrealized Holding Losses	23	8
Estimated Fair Value	3,685	3,154
Debt Securities, Available-for-sale
Estimated Fair Value	1,250	1,172
Total Investments
Unrealized Holding Gains	2,529	1,957
Unrealized Holding Losses	24	10
Estimated Fair Value	4,965	4,347
Duke Energy Carolinas | NDTF | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	30	21
Duke Energy Carolinas | NDTF | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	49	21
Gross Unrealized Holding Losses	1	1
Estimated Fair Value	510	361
Duke Energy Carolinas | NDTF | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	6	3
Estimated Fair Value	91	96
Duke Energy Carolinas | NDTF | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	25	16
Gross Unrealized Holding Losses		1
Estimated Fair Value	475	578
Duke Energy Carolinas | NDTF | Other debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	7	3
Estimated Fair Value	174	137
Progress Energy
Debt Securities, Available-for-sale
Estimated Fair Value	1,493
Total Investments
Unrealized Holding Gains	1,769	1,655
Unrealized Holding Losses	31	47
Estimated Fair Value	4,296	3,883
Progress Energy | NDTF
Equity Securities, FV-NI
Gross Unrealized Holding Gains	1,696	1,609
Gross Unrealized Holding Losses	31	47
Estimated Fair Value	2,550	2,507
Debt Securities, Available-for-sale
Estimated Fair Value	1,467	1,196
Total Investments
Unrealized Holding Gains	1,766	1,652
Unrealized Holding Losses	31	47
Estimated Fair Value	4,164	3,783
Progress Energy | NDTF | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	147	80
Progress Energy | NDTF | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	27	16
Gross Unrealized Holding Losses	0
Estimated Fair Value	296	242
Progress Energy | NDTF | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	16	10
Gross Unrealized Holding Losses	0
Estimated Fair Value	279	272
Progress Energy | NDTF | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	26	17
Gross Unrealized Holding Losses	0
Estimated Fair Value	886	678
Progress Energy | NDTF | Other debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	1	0
Gross Unrealized Holding Losses	0	0
Estimated Fair Value	6	4
Progress Energy | Other Investments
Debt Securities, Available-for-sale
Estimated Fair Value	26	51
Total Investments
Unrealized Holding Gains	3	3
Unrealized Holding Losses	0	0
Estimated Fair Value	132	100
Progress Energy | Other Investments | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	106	49
Progress Energy | Other Investments | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	3	3
Gross Unrealized Holding Losses	0	0
Estimated Fair Value	26	51
Duke Energy Progress
Debt Securities, Available-for-sale
Estimated Fair Value	993
Total Investments
Unrealized Holding Gains	1,687	1,300
Unrealized Holding Losses	31	21
Estimated Fair Value	3,529	3,053
Duke Energy Progress | NDTF
Equity Securities, FV-NI
Gross Unrealized Holding Gains	1,617	1,258
Gross Unrealized Holding Losses	31	21
Estimated Fair Value	2,459	2,077
Debt Securities, Available-for-sale
Estimated Fair Value	993	921
Total Investments
Unrealized Holding Gains	1,687	1,300
Unrealized Holding Losses	31	21
Estimated Fair Value	3,528	3,051
Duke Energy Progress | NDTF | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	76	53
Duke Energy Progress | NDTF | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	27	16
Estimated Fair Value	296	242
Duke Energy Progress | NDTF | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	16	10
Estimated Fair Value	279	272
Duke Energy Progress | NDTF | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	26	16
Estimated Fair Value	412	403
Duke Energy Progress | NDTF | Other debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	1	0
Gross Unrealized Holding Losses	0	0
Estimated Fair Value	6	4
Duke Energy Progress | Other Investments
Total Investments
Unrealized Holding Gains	0	0
Unrealized Holding Losses	0	0
Estimated Fair Value	1	2
Duke Energy Progress | Other Investments | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	1	2
Duke Energy Florida
Debt Securities, Available-for-sale
Estimated Fair Value	500
Total Investments
Unrealized Holding Gains	82	355
Unrealized Holding Losses	0	26
Estimated Fair Value	663	787
Duke Energy Florida | NDTF
Equity Securities, FV-NI
Gross Unrealized Holding Gains	79	351
Gross Unrealized Holding Losses		26
Estimated Fair Value	91	430
Debt Securities, Available-for-sale
Estimated Fair Value	474	275
Total Investments
Unrealized Holding Gains	79	352
Unrealized Holding Losses	0	26
Estimated Fair Value	636	732
Duke Energy Florida | NDTF | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	71	27
Duke Energy Florida | NDTF | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		1
Estimated Fair Value	474	275
Duke Energy Florida | Other Investments
Debt Securities, Available-for-sale
Estimated Fair Value	26	51
Total Investments
Unrealized Holding Gains	3	3
Unrealized Holding Losses	0	0
Estimated Fair Value	27	55
Duke Energy Florida | Other Investments | Cash and cash equivalents
Available-for-sale Securities
Cash and cash equivalents	1	4
Duke Energy Florida | Other Investments | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	3	3
Gross Unrealized Holding Losses	0	0
Estimated Fair Value	26	51
Duke Energy Indiana
Debt Securities, Available-for-sale
Estimated Fair Value	45
Total Investments
Unrealized Holding Gains	59	44
Unrealized Holding Losses		0
Estimated Fair Value	143	125
Duke Energy Indiana | Other Investments
Available-for-sale Securities
Cash and cash equivalents	1
Equity Securities, FV-NI
Gross Unrealized Holding Gains	58	43
Gross Unrealized Holding Losses	0	0
Estimated Fair Value	97	81
Debt Securities, Available-for-sale
Estimated Fair Value	45	44
Duke Energy Indiana | Other Investments | Corporate debt securities
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	0	0
Gross Unrealized Holding Losses	0	0
Estimated Fair Value	3	6
Duke Energy Indiana | Other Investments | Municipal bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	1	1
Gross Unrealized Holding Losses	0	0
Estimated Fair Value	38	36
Duke Energy Indiana | Other Investments | U.S. government bonds
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	0	0
Estimated Fair Value	$ 4	$ 2

Investments in Debt and Equit_4

Investments in Debt and Equity Securities (Maturities) (Details) $ in Millions	Dec. 31, 2020USD ($)
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	$ 149
Due after one through five years	922
Due after five through 10 years	671
Due after 10 years	1,260
Total	3,002
Duke Energy Carolinas
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	14
Due after one through five years	299
Due after five through 10 years	279
Due after 10 years	658
Total	1,250
Progress Energy
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	109
Due after one through five years	567
Due after five through 10 years	298
Due after 10 years	519
Total	1,493
Duke Energy Progress
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	21
Due after one through five years	259
Due after five through 10 years	210
Due after 10 years	503
Total	993
Duke Energy Florida
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	88
Due after one through five years	308
Due after five through 10 years	88
Due after 10 years	16
Total	500
Duke Energy Indiana
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	3
Due after one through five years	17
Due after five through 10 years	10
Due after 10 years	15
Total	$ 45

Investments in Debt and Equit_5

Investments in Debt and Equity Securities (Realized Gains and Losses) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
FV-NI:
Realized gains	$ 366	$ 172	$ 168
Realized losses	174	151	126
AFS:
Realized gains	96	94	22
Realized losses	51	67	51
Duke Energy Carolinas
FV-NI:
Realized gains	64	113	89
Realized losses	99	107	73
AFS:
Realized gains	60	55	19
Realized losses	37	38	35
Progress Energy
FV-NI:
Realized gains	302	59	79
Realized losses	75	44	53
AFS:
Realized gains	24	36	3
Realized losses	13	29	15
Duke Energy Progress
FV-NI:
Realized gains	52	38	68
Realized losses	59	33	48
AFS:
Realized gains	24	7	2
Realized losses	13	5	10
Duke Energy Florida
FV-NI:
Realized gains	250	21	11
Realized losses	16	11	5
AFS:
Realized gains	0	29	1
Realized losses	$ 0	$ 24	$ 5

Fair Value Measurements (Fair V

Fair Value Measurements (Fair Value Measurement Amounts for Assets and Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	$ 3,002
Derivative assets	61	$ 25
Total assets	9,748	8,610
Derivative liabilities	(324)	(277)
Net assets (liabilities)	9,424	8,310
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1	3
Total assets	7,551	6,675
Derivative liabilities	0	(15)
Net assets (liabilities)	7,551	6,660
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	53	7
Total assets	2,144	1,869
Derivative liabilities	(240)	(145)
Net assets (liabilities)	1,904	1,701
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	7	15
Total assets	7	15
Derivative liabilities	(84)	(117)
Net assets (liabilities)	(77)	(102)
Not Categorized
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	46	51
Net assets (liabilities)	46	51
NDTF
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	177	101
Equity securities, FV-NI	6,235	5,661
Debt securities, available-for-sale	2,717	2,368
NDTF | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	177	101
Debt securities, available-for-sale	874	725
NDTF | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Debt securities, available-for-sale	1,843	1,643
NDTF | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
NDTF | Not Categorized
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
NDTF equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	6,235	5,684
Derivative liabilities		(23)
NDTF equity securities | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	6,189	5,633
Derivative liabilities		0
NDTF equity securities | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities		(23)
NDTF equity securities | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities		0
NDTF equity securities | Not Categorized
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	46	51
Other Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	146	122
Debt securities, available-for-sale	285	258
Other Investments | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	146	122
Debt securities, available-for-sale	37	39
Other Investments | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	248	219
Other cash and cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	127	52
Other cash and cash equivalents | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	127	52
Other cash and cash equivalents | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Other cash and cash equivalents | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Other cash and cash equivalents | Not Categorized
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Duke Energy Carolinas
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI		3,154
Debt securities, available-for-sale	1,250
Total assets	4,985	4,347
Derivative liabilities	(20)	(49)
Net assets (liabilities)	4,965	4,298
Duke Energy Carolinas | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI		3,103
Total assets	3,861	3,330
Net assets (liabilities)	3,861	3,330
Duke Energy Carolinas | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	1,078	966
Derivative liabilities	(20)	(49)
Net assets (liabilities)	1,058	917
Duke Energy Carolinas | Not Categorized
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI		51
Total assets	46	51
Net assets (liabilities)	46	51
Duke Energy Carolinas | NDTF
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	30	21
Equity securities, FV-NI	3,685	3,154
Debt securities, available-for-sale	1,250	1,172
Derivative assets	20
Duke Energy Carolinas | NDTF | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	30	21
Debt securities, available-for-sale	192	206
Derivative assets	0
Duke Energy Carolinas | NDTF | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Debt securities, available-for-sale	1,058	966
Derivative assets	20
Duke Energy Carolinas | NDTF | Not Categorized
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Derivative assets	0
Duke Energy Carolinas | NDTF equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	3,685
Duke Energy Carolinas | NDTF equity securities | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	3,639
Duke Energy Carolinas | NDTF equity securities | Not Categorized
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	46
Progress Energy
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	1,493
Derivative assets	33	7
Total assets	4,329	3,913
Derivative liabilities	(29)	(65)
Net assets (liabilities)	4,300	3,825
Progress Energy | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	3,485	3,178
Net assets (liabilities)	3,485	3,178
Progress Energy | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	33	7
Total assets	844	735
Derivative liabilities	(29)	(65)
Net assets (liabilities)	815	647
Progress Energy | NDTF
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	147	80
Equity securities, FV-NI	2,550	2,507
Debt securities, available-for-sale	1,467	1,196
Derivative liabilities		(23)
Progress Energy | NDTF | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	147	80
Debt securities, available-for-sale	682	519
Progress Energy | NDTF | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Debt securities, available-for-sale	785	677
Derivative liabilities		(23)
Progress Energy | NDTF equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	2,550	2,530
Progress Energy | NDTF equity securities | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	2,550	2,530
Progress Energy | Other Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	26	51
Progress Energy | Other Investments | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	26	51
Progress Energy | Other cash and cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	106	49
Progress Energy | Other cash and cash equivalents | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	106	49
Progress Energy | Other cash and cash equivalents | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents		0
Duke Energy Progress
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	993
Derivative assets	33
Total assets	3,562	3,053
Derivative liabilities	(14)	(49)
Net assets (liabilities)	3,548	3,004
Duke Energy Progress | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	2,773	2,376
Net assets (liabilities)	2,773	2,376
Duke Energy Progress | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	33	0
Total assets	789	677
Derivative liabilities	(14)	(49)
Net assets (liabilities)	775	628
Duke Energy Progress | NDTF
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	76	53
Equity securities, FV-NI	2,459	2,077
Debt securities, available-for-sale	993	921
Duke Energy Progress | NDTF | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	76	53
Debt securities, available-for-sale	237	244
Duke Energy Progress | NDTF | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Debt securities, available-for-sale	756	677
Duke Energy Progress | NDTF equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	2,459	2,077
Duke Energy Progress | NDTF equity securities | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	2,459	2,077
Duke Energy Progress | Other cash and cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1	2
Duke Energy Progress | Other cash and cash equivalents | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1	2
Duke Energy Progress | Other cash and cash equivalents | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Duke Energy Florida
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	500
Derivative assets		7
Total assets	663	817
Derivative liabilities		(1)
Net assets (liabilities)	663	793
Duke Energy Florida | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	608	759
Net assets (liabilities)	608	759
Duke Energy Florida | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets		7
Total assets	55	58
Derivative liabilities		(1)
Net assets (liabilities)	55	34
Duke Energy Florida | NDTF
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	71	27
Equity securities, FV-NI	91	430
Debt securities, available-for-sale	474	275
Derivative liabilities		(23)
Duke Energy Florida | NDTF | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	71	27
Debt securities, available-for-sale	445	275
Duke Energy Florida | NDTF | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Debt securities, available-for-sale	29
Derivative liabilities		(23)
Duke Energy Florida | NDTF equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	91	453
Duke Energy Florida | NDTF equity securities | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	91	453
Duke Energy Florida | Other Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	26	51
Duke Energy Florida | Other Investments | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	26	51
Duke Energy Florida | Other cash and cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1	4
Duke Energy Florida | Other cash and cash equivalents | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1	4
Duke Energy Florida | Other cash and cash equivalents | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Duke Energy Indiana
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	45
Derivative assets	6	13
Total assets	149	138
Derivative liabilities	(1)	(1)
Net assets (liabilities)	148	137
Duke Energy Indiana | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets		2
Total assets	98	83
Derivative liabilities	(1)	(1)
Net assets (liabilities)	97	82
Duke Energy Indiana | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	45	44
Net assets (liabilities)	45	44
Duke Energy Indiana | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	6	11
Total assets	6	11
Net assets (liabilities)	6	11
Duke Energy Indiana | Other Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	97	81
Debt securities, available-for-sale	45	44
Duke Energy Indiana | Other Investments | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	97	81
Duke Energy Indiana | Other Investments | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	45	44
Duke Energy Indiana | Other cash and cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1	0
Duke Energy Indiana | Other cash and cash equivalents | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1	0
Duke Energy Indiana | Other cash and cash equivalents | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Duke Energy Indiana | Other cash and cash equivalents | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Piedmont
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1	1
Derivative liabilities	(122)	(117)
Net assets (liabilities)	(121)	(116)
Piedmont | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1	1
Net assets (liabilities)	1	1
Piedmont | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	(122)
Net assets (liabilities)	$ (122)
Piedmont | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities		(117)
Net assets (liabilities)		$ (117)

Fair Value Measurements (Reconc

Fair Value Measurements (Reconciliation of Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Unobservable Inputs) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Derivatives (net)
Balance at beginning of period	$ (102)	$ (113)
Total pretax realized or unrealized losses included in comprehensive income	(84)	0
Purchases	14	37
Settlements	(19)	(44)
Net transfers Out of Level 3	117	0
Total gains (losses) included on the Consolidated Balance Sheet	(3)	18
Ending balance	(77)	(102)
Duke Energy Indiana
Derivatives (net)
Balance at beginning of period	11	22
Purchases	10	28
Settlements	(13)	(36)
Total gains (losses) included on the Consolidated Balance Sheet	(2)	(3)
Ending balance	6	11
Piedmont
Derivatives (net)
Balance at beginning of period	(117)	(141)
Net transfers Out of Level 3	117	0
Total gains (losses) and settlements	0	24
Ending balance	$ 0	$ (117)

Fair Value Measurements (Quanti

Fair Value Measurements (Quantitative Level 3 Fair Value Disclosure) (Details) $ in Millions	Dec. 31, 2020USD ($)$ / MWh	Dec. 31, 2019USD ($)$ / MWh$ / MMBTU	Dec. 31, 2018USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Net derivative asset (liability) | $	$ (77)	$ (102)	$ (113)
Forward natural gas curves – price per MMBtu | Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Net derivative asset (liability) | $	$ (84)
Forward natural gas curves – price per MMBtu | Minimum | Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Input measurement (in usd per MWh and usd per MMBtu)	14.68
Forward natural gas curves – price per MMBtu | Maximum | Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Input measurement (in usd per MWh and usd per MMBtu)	151.84
Forward natural gas curves – price per MMBtu | Weighted Average | Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Input measurement (in usd per MWh and usd per MMBtu)	28.84
Duke Energy Ohio | FTR price – per MWh | RTO auction pricing
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Net derivative asset (liability) | $	$ 1	$ 4
Duke Energy Ohio | FTR price – per MWh | Minimum | RTO auction pricing
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Input measurement (in usd per MWh and usd per MMBtu)	0.25	0.59
Duke Energy Ohio | FTR price – per MWh | Maximum | RTO auction pricing
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Input measurement (in usd per MWh and usd per MMBtu)	1.68	3.47
Duke Energy Ohio | FTR price – per MWh | Weighted Average | RTO auction pricing
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Input measurement (in usd per MWh and usd per MMBtu)	0.79	2.07
Duke Energy Indiana
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Net derivative asset (liability) | $	$ 6	$ 11	22
Duke Energy Indiana | FTR price – per MWh | RTO auction pricing
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Net derivative asset (liability) | $	$ 6	$ 11
Duke Energy Indiana | FTR price – per MWh | Minimum | RTO auction pricing
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Input measurement (in usd per MWh and usd per MMBtu)	(2.40)	(0.66)
Duke Energy Indiana | FTR price – per MWh | Maximum | RTO auction pricing
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Input measurement (in usd per MWh and usd per MMBtu)	7.41	9.24
Duke Energy Indiana | FTR price – per MWh | Weighted Average | RTO auction pricing
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Input measurement (in usd per MWh and usd per MMBtu)	1.05	1.15
Piedmont
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Net derivative asset (liability) | $	$ 0	$ (117)	$ (141)
Piedmont | Forward natural gas curves – price per MMBtu | Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Net derivative asset (liability) | $		$ (117)
Piedmont | Forward natural gas curves – price per MMBtu | Minimum | Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Input measurement (in usd per MWh and usd per MMBtu) | $ / MMBTU		1.59
Piedmont | Forward natural gas curves – price per MMBtu | Maximum | Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Input measurement (in usd per MWh and usd per MMBtu) | $ / MMBTU		2.46
Piedmont | Forward natural gas curves – price per MMBtu | Weighted Average | Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Input measurement (in usd per MWh and usd per MMBtu) | $ / MMBTU		1.91

Fair Value Measurements (Other

Fair Value Measurements (Other Fair Value Disclosures) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt	$ 59,863	$ 58,126
Long-term debt, fair value	69,292	63,062
Unamortized debt discount and premium, net	1,300	1,500
Duke Energy Carolinas
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt	12,218	11,900
Long-term debt, fair value	14,917	13,516
Progress Energy
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt	19,264	19,634
Long-term debt, fair value	23,470	22,291
Duke Energy Progress
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt	9,258	9,058
Long-term debt, fair value	10,862	9,934
Duke Energy Florida
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt	7,915	7,987
Long-term debt, fair value	9,756	9,131
Duke Energy Ohio
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt	3,089	2,619
Long-term debt, fair value	3,650	2,964
Duke Energy Indiana
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt	4,091	4,057
Long-term debt, fair value	5,204	4,800
Piedmont
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt	2,780	2,384
Long-term debt, fair value	$ 3,306	$ 2,642

Variable Interest Entities (Nar

Variable Interest Entities (Narrative) (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Consolidated VIEs
Variable Interest Entity [Line Items]
Financial support		$ 0	$ 0	$ 0
FES
Variable Interest Entity [Line Items]
Power Purchase Participation Rate	4.85%
ACP | Non-consolidated VIEs
Variable Interest Entity [Line Items]
VIE Ownership interest		47.00%
CRC
Variable Interest Entity [Line Items]
Variation in credit losses		10.00%
Variation in discount rates		20.00%
CRC | Consolidated VIEs
Variable Interest Entity [Line Items]
Percent of proceeds received as cash		75.00%
Percent of proceeds received as subordinated note		25.00%
Minimum Equity Balance required by Cinergy Receivables		$ 3,000,000
CRC | Duke Energy Ohio | Non-consolidated VIEs
Variable Interest Entity [Line Items]
Fixed interest rate added to LIBOR to compute variable rate		1.00%
OVEC | Duke Energy Ohio | Non-consolidated VIEs
Variable Interest Entity [Line Items]
VIE Ownership interest		9.00%

Variable Interest Entities (Sch

Variable Interest Entities (Schedule of Accounts Receivable Securitizations) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Variable Interest Entity [Line Items]
Long-Term Debt	$ 55,625	$ 54,985
Duke Energy Carolinas
Variable Interest Entity [Line Items]
Long-Term Debt	11,412	11,142
Duke Energy Progress
Variable Interest Entity [Line Items]
Long-Term Debt	8,505	7,902
Duke Energy Florida
Variable Interest Entity [Line Items]
Long-Term Debt	7,092	7,416
CRC | Consolidated VIEs
Variable Interest Entity [Line Items]
Facility size	350
Long-Term Debt	350	350
Restricted Receivables	547	522
DERF | Duke Energy Carolinas | Consolidated VIEs
Variable Interest Entity [Line Items]
Facility size	475
Long-Term Debt	364	474
Restricted Receivables	696	642
DEPR | Duke Energy Progress | Consolidated VIEs
Variable Interest Entity [Line Items]
Facility size	350
Long-Term Debt	250	325
Restricted Receivables	500	489
DEFR | Duke Energy Florida | Consolidated VIEs
Variable Interest Entity [Line Items]
Facility size	250
Long-Term Debt	250	250
Restricted Receivables	$ 397	$ 336

Variable Interest Entities (Con

Variable Interest Entities (Consolidated VIEs) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Variable Interest Entity [Line Items]
Regulatory Assets: Current	$ 1,641	$ 1,796
Current Assets: Other	462	764
Property, Plant and Equipment: Cost	155,580	147,654
Accumulated depreciation and amortization	(48,827)	(45,773)
Other Noncurrent Assets: Other	3,601	3,289
Other Noncurrent Assets: Regulatory assets	12,421	13,222
Current Liabilities: Other	2,936	2,367
Current maturities of long-term debt	4,238	3,141
Long-Term Debt	55,625	54,985
Asset retirement obligations	12,286	12,437
Other Noncurrent Liabilities: Other	1,719	1,581
Duke Energy Florida
Variable Interest Entity [Line Items]
Regulatory Assets: Current	265	419
Current Assets: Other	41	58
Property, Plant and Equipment: Cost	22,123	20,457
Accumulated depreciation and amortization	(5,560)	(5,236)
Other Noncurrent Assets: Other	335	311
Other Noncurrent Assets: Regulatory assets	1,799	2,194
Current Liabilities: Other	374	415
Current maturities of long-term debt	823	571
Long-Term Debt	7,092	7,416
Asset retirement obligations	514	578
Other Noncurrent Liabilities: Other	209	136
DEFPF | Duke Energy Florida | Consolidated VIEs
Variable Interest Entity [Line Items]
Receivables of VIEs	4	5
Regulatory Assets: Current	53	52
Current Assets: Other	39	39
Other Noncurrent Assets: Regulatory assets	937	989
Current Liabilities: Other	10	10
Current maturities of long-term debt	55	54
Long-Term Debt	1,002	1,057
Commercial Renewables | Consolidated VIEs
Variable Interest Entity [Line Items]
Current Assets: Other	257	203
Property, Plant and Equipment: Cost	6,394	5,747
Accumulated depreciation and amortization	(1,242)	(1,041)
Other Noncurrent Assets: Other	67	106
Current maturities of long-term debt	167	162
Long-Term Debt	1,569	1,541
Asset retirement obligations	148	127
Other Noncurrent Liabilities: Other	$ 316	$ 228

Variable Interest Entities (S_2

Variable Interest Entities (Schedule of Non-Consolidated VIEs) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Variable Interest Entity [Line Items]
Investments in equity method unconsolidated affiliates	$ 961	$ 1,936	$ 1,409
Other noncurrent assets	3,601	3,289
Total Assets	162,388	158,838	145,392
Other current liabilities	2,936	2,367
Deferred income taxes	9,244	8,878
Other Noncurrent Liabilities: Other	1,719	1,581
Non-consolidated VIEs
Variable Interest Entity [Line Items]
Receivables from affiliated companies		(1)
Investments in equity method unconsolidated affiliates	530	1,479
Other noncurrent assets	31
Total Assets	561	1,478
Taxes accrued		(1)
Other current liabilities	933	4
Deferred income taxes		59
Other Noncurrent Liabilities: Other	18	11
Total liabilities	951	73
Net assets (liabilities)	(390)	1,405
Duke Energy Ohio
Variable Interest Entity [Line Items]
Receivables from affiliated companies	102	92
Other noncurrent assets	72	52
Total Assets	10,025	9,338	$ 8,555
Other current liabilities	70	75
Deferred income taxes	981	922
Other Noncurrent Liabilities: Other	99	94
Duke Energy Ohio | Non-consolidated VIEs
Variable Interest Entity [Line Items]
Receivables from affiliated companies	83	64
Total Assets	83	64
Net assets (liabilities)	83	64
Duke Energy Indiana
Variable Interest Entity [Line Items]
Receivables from affiliated companies	112	79
Other noncurrent assets	253	234
Total Assets	14,041	13,276
Other current liabilities	83	112
Deferred income taxes	1,228	1,150
Other Noncurrent Liabilities: Other	30	18
Duke Energy Indiana | Non-consolidated VIEs
Variable Interest Entity [Line Items]
Receivables from affiliated companies	110	77
Total Assets	110	77
Net assets (liabilities)	110	77
Pipeline Investments | Non-consolidated VIEs
Variable Interest Entity [Line Items]
Investments in equity method unconsolidated affiliates		1,179
Other noncurrent assets	31
Total Assets	31	1,179
Taxes accrued		(1)
Other current liabilities	928
Deferred income taxes		59
Other Noncurrent Liabilities: Other	8
Total liabilities	936	58
Net assets (liabilities)	(905)	1,121
Commercial Renewables | Non-consolidated VIEs
Variable Interest Entity [Line Items]
Receivables from affiliated companies		(1)
Investments in equity method unconsolidated affiliates	530	300
Total Assets	530	299
Other current liabilities	5	4
Other Noncurrent Liabilities: Other	10	11
Total liabilities	15	15
Net assets (liabilities)	$ 515	$ 284

Variable Interest Entities (Fai

Variable Interest Entities (Fair Value Assumptions) (Details) - CRC - Non-consolidated VIEs	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Duke Energy Ohio
Variable Interest Entity [Line Items]
Anticipated credit loss ratio	0.50%	0.60%
Discount rate	1.60%	3.30%
Receivable turnover rate	13.40%	13.40%
Duke Energy Indiana
Variable Interest Entity [Line Items]
Anticipated credit loss ratio	0.30%	0.30%
Discount rate	1.60%	3.30%
Receivable turnover rate	11.30%	11.50%

Variable Interest Entities (Rec

Variable Interest Entities (Receivables Sold) (Details) - CRC - Non-consolidated VIEs - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Duke Energy Ohio
Variable Interest Entity [Line Items]
Receivables sold	$ 270	$ 253
Less: Retained interests	83	64
Net receivables sold	187	189
Duke Energy Indiana
Variable Interest Entity [Line Items]
Receivables sold	344	307
Less: Retained interests	110	77
Net receivables sold	$ 234	$ 230

Variable Interest Entities (Sal

Variable Interest Entities (Sales and Cash Flows) (Details) - Non-consolidated VIEs - CRC - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Duke Energy Ohio
Variable Interest Entity [Line Items]
Receivables sold	$ 1,905	$ 1,979	$ 1,987
Loss recognized on sale	10	14	13
Cash proceeds from receivables sold	1,875	1,993	1,967
Collection fees received	1	1	1
Return received on retained interests	4	6	6
Duke Energy Indiana
Variable Interest Entity [Line Items]
Receivables sold	2,631	2,837	2,842
Loss recognized on sale	12	17	16
Cash proceeds from receivables sold	2,586	2,860	2,815
Collection fees received	1	1	1
Return received on retained interests	$ 5	$ 9	$ 9

Revenue (Remaining Performance

Revenue (Remaining Performance Obligations) (Details) $ in Millions	Dec. 31, 2020USD ($)
Progress Energy
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 347
Progress Energy | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 93
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Progress Energy | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 107
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Progress Energy | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 44
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Progress Energy | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 45
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Progress Energy | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 7
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Progress Energy | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 51
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Progress
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 32
Duke Energy Progress | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 8
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Progress | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 8
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Progress | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 8
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Progress | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 8
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Progress | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Progress | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Florida
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 315
Duke Energy Florida | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 85
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Florida | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 99
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Florida | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 36
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Florida | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 37
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Florida | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 7
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Florida | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 51
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Indiana
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 60
Duke Energy Indiana | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 5
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Indiana | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Indiana | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 7
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Indiana | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 12
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Indiana | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 12
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Duke Energy Indiana | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 24
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Piedmont
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 626
Piedmont | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 65
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Piedmont | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 64
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Piedmont | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 61
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Piedmont | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 59
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Piedmont | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 58
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Piedmont | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 319
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year

Revenue (Disaggregation of Reve

Revenue (Disaggregation of Revenue) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 23,480	$ 24,348	$ 23,757
Revenue from sources other than contracts with customers	388	731	764
Total operating revenues	23,868	25,079	24,521
Other
Disaggregation of Revenue [Line Items]
Total operating revenues	1,069	1,037	1,081
Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	21,637	22,347	21,729
Total operating revenues	21,687	22,798	22,242
Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	9,806	9,863	9,587
Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	6,194	6,431	6,127
Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,859	3,071	2,974
Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,864	2,212	2,324
Electric Utilities and Infrastructure | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	914	770	717
Total operating revenues	944	855	915
Gas Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,590	1,754	1,800
Total operating revenues	1,653	1,770	1,783
Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	930	976	1,000
Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Commercial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	446	508	514
Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	127	141	147
Gas Utilities and Infrastructure | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	87	129	139
Total operating revenues	57	84	64
Commercial Renewables
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	227	223	209
Total operating revenues	502	487	477
Commercial Renewables | Other
Disaggregation of Revenue [Line Items]
Total operating revenues	68	98	102
Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	26	24	19
Total operating revenues	26	24	19
Duke Energy Carolinas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	7,028	7,241	7,108
Revenue from sources other than contracts with customers	(13)	154	192
Total operating revenues	7,015	7,395	7,300
Duke Energy Carolinas | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	7,028	7,241	7,108
Duke Energy Carolinas | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,997	3,044	2,981
Duke Energy Carolinas | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,233	2,244	2,119
Duke Energy Carolinas | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,137	1,215	1,180
Duke Energy Carolinas | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	380	462	508
Duke Energy Carolinas | Electric Utilities and Infrastructure | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	281	276	320
Progress Energy
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	10,521	10,883	10,462
Revenue from sources other than contracts with customers	106	319	266
Total operating revenues	10,627	11,202	10,728
Progress Energy | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	10,521	10,883	10,462
Progress Energy | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	5,017	4,998	4,785
Progress Energy | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,779	2,935	2,809
Progress Energy | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	901	934	904
Progress Energy | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,228	1,468	1,462
Progress Energy | Electric Utilities and Infrastructure | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	596	548	502
Duke Energy Progress
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	5,348	5,785	5,564
Revenue from sources other than contracts with customers	74	172	135
Total operating revenues	5,422	5,957	5,699
Duke Energy Progress | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	5,348	5,785	5,564
Duke Energy Progress | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,059	2,144	2,019
Duke Energy Progress | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,312	1,368	1,280
Duke Energy Progress | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	649	675	642
Duke Energy Progress | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,034	1,281	1,303
Duke Energy Progress | Electric Utilities and Infrastructure | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	294	317	320
Duke Energy Florida
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	5,173	5,098	4,898
Revenue from sources other than contracts with customers	15	133	123
Total operating revenues	5,188	5,231	5,021
Duke Energy Florida | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	5,173	5,098	4,898
Duke Energy Florida | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,958	2,854	2,766
Duke Energy Florida | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,467	1,567	1,529
Duke Energy Florida | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	252	259	262
Duke Energy Florida | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	194	187	159
Duke Energy Florida | Electric Utilities and Infrastructure | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	302	231	182
Duke Energy Ohio
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,870	1,940	1,930
Revenue from sources other than contracts with customers	(12)		27
Total operating revenues	1,858	1,940	1,957
Duke Energy Ohio | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,419	1,457	1,426
Duke Energy Ohio | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	726	733	743
Duke Energy Ohio | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	442	451	422
Duke Energy Ohio | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	137	147	131
Duke Energy Ohio | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	32	46	57
Duke Energy Ohio | Electric Utilities and Infrastructure | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	82	80	73
Duke Energy Ohio | Gas Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	451	483	503
Duke Energy Ohio | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	300	315	331
Duke Energy Ohio | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Commercial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	117	130	135
Duke Energy Ohio | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	17	19	18
Duke Energy Ohio | Gas Utilities and Infrastructure | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	17	19	19
Duke Energy Ohio | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers			1
Duke Energy Indiana
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,783	2,987	3,003
Revenue from sources other than contracts with customers	12	17	56
Total operating revenues	2,795	3,004	3,059
Duke Energy Indiana | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,783	2,987	3,003
Duke Energy Indiana | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,064	1,087	1,076
Duke Energy Indiana | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	740	802	778
Duke Energy Indiana | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	683	774	760
Duke Energy Indiana | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	224	235	298
Duke Energy Indiana | Electric Utilities and Infrastructure | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	72	89	91
Piedmont
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,173	1,322	1,349
Revenue from sources other than contracts with customers	124	59	26
Total operating revenues	1,297	1,381	1,375
Piedmont | Gas Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,173	1,322	1,349
Piedmont | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	630	661	669
Piedmont | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Commercial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	329	378	378
Piedmont | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	110	122	128
Piedmont | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Power Generation
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	34	51	54
Piedmont | Gas Utilities and Infrastructure | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 70	$ 110	$ 120

Revenue (Reserve for Credit Los

Revenue (Reserve for Credit Losses for Trade and Other Receivables) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at December 31, 2019	$ 76
Cumulative Change in Accounting Principle	146
Write-Offs	58
Credit Loss Expense	75
Other Adjustments	48
Balance at December 31, 2020	146
Duke Energy Carolinas
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at December 31, 2019	10
Cumulative Change in Accounting Principle	23
Write-Offs	13
Credit Loss Expense	13
Other Adjustments	12
Balance at December 31, 2020	23
Progress Energy
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at December 31, 2019	16
Cumulative Change in Accounting Principle	37
Write-Offs	23
Credit Loss Expense	29
Other Adjustments	13
Balance at December 31, 2020	37
Duke Energy Progress
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at December 31, 2019	8
Cumulative Change in Accounting Principle	23
Write-Offs	8
Credit Loss Expense	9
Other Adjustments	13
Balance at December 31, 2020	23
Duke Energy Florida
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at December 31, 2019	7
Cumulative Change in Accounting Principle	14
Write-Offs	14
Credit Loss Expense	20
Balance at December 31, 2020	14
Duke Energy Ohio
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at December 31, 2019	4
Cumulative Change in Accounting Principle	4
Balance at December 31, 2020	4
Duke Energy Indiana
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at December 31, 2019	3
Cumulative Change in Accounting Principle	3
Balance at December 31, 2020	3
Piedmont
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at December 31, 2019	6
Cumulative Change in Accounting Principle	12
Write-Offs	6
Credit Loss Expense	11
Balance at December 31, 2020	12
Cumulative Change in Accounting Principle
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at December 31, 2019	5
Cumulative Change in Accounting Principle	5
Cumulative Change in Accounting Principle | Duke Energy Carolinas
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at December 31, 2019	1
Cumulative Change in Accounting Principle	1
Cumulative Change in Accounting Principle | Progress Energy
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at December 31, 2019	2
Cumulative Change in Accounting Principle	2
Cumulative Change in Accounting Principle | Duke Energy Progress
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at December 31, 2019	1
Cumulative Change in Accounting Principle	1
Cumulative Change in Accounting Principle | Duke Energy Florida
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at December 31, 2019	1
Cumulative Change in Accounting Principle	1
Cumulative Change in Accounting Principle | Piedmont
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at December 31, 2019	1
Cumulative Change in Accounting Principle	$ 1

Revenue (Aging of Trade Receiva

Revenue (Aging of Trade Receivables) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Past Due [Line Items]
Unbilled receivables	$ 969	$ 843
Not past due	1,789
Deferred Payment Arrangements	215
Trade and Other Receivables	3,299
30-60 days
Financing Receivable, Past Due [Line Items]
Past due	185
60-90 days
Financing Receivable, Past Due [Line Items]
Past due	22
90+ days
Financing Receivable, Past Due [Line Items]
Past due	119
Duke Energy Carolinas
Financing Receivable, Past Due [Line Items]
Unbilled receivables	328	298
Not past due	445
Deferred Payment Arrangements	96
Trade and Other Receivables	966
Duke Energy Carolinas | 30-60 days
Financing Receivable, Past Due [Line Items]
Past due	80
Duke Energy Carolinas | 60-90 days
Financing Receivable, Past Due [Line Items]
Past due	1
Duke Energy Carolinas | 90+ days
Financing Receivable, Past Due [Line Items]
Past due	16
Progress Energy
Financing Receivable, Past Due [Line Items]
Unbilled receivables	283	217
Not past due	707
Deferred Payment Arrangements	80
Trade and Other Receivables	1,166
Progress Energy | 30-60 days
Financing Receivable, Past Due [Line Items]
Past due	54
Progress Energy | 60-90 days
Financing Receivable, Past Due [Line Items]
Past due	10
Progress Energy | 90+ days
Financing Receivable, Past Due [Line Items]
Past due	32
Duke Energy Progress
Financing Receivable, Past Due [Line Items]
Unbilled receivables	167	122
Not past due	398
Deferred Payment Arrangements	52
Trade and Other Receivables	655
Duke Energy Progress | 30-60 days
Financing Receivable, Past Due [Line Items]
Past due	25
Duke Energy Progress | 60-90 days
Financing Receivable, Past Due [Line Items]
Past due	4
Duke Energy Progress | 90+ days
Financing Receivable, Past Due [Line Items]
Past due	9
Duke Energy Florida
Financing Receivable, Past Due [Line Items]
Unbilled receivables	116	95
Not past due	307
Deferred Payment Arrangements	28
Trade and Other Receivables	509
Duke Energy Florida | 30-60 days
Financing Receivable, Past Due [Line Items]
Past due	29
Duke Energy Florida | 60-90 days
Financing Receivable, Past Due [Line Items]
Past due	6
Duke Energy Florida | 90+ days
Financing Receivable, Past Due [Line Items]
Past due	23
Duke Energy Ohio
Financing Receivable, Past Due [Line Items]
Unbilled receivables	2	1
Not past due	60
Trade and Other Receivables	102
Duke Energy Ohio | 30-60 days
Financing Receivable, Past Due [Line Items]
Past due	8
Duke Energy Ohio | 60-90 days
Financing Receivable, Past Due [Line Items]
Past due	2
Duke Energy Ohio | 90+ days
Financing Receivable, Past Due [Line Items]
Past due	30
Duke Energy Indiana
Financing Receivable, Past Due [Line Items]
Unbilled receivables	16	16
Not past due	26
Trade and Other Receivables	58
Duke Energy Indiana | 30-60 days
Financing Receivable, Past Due [Line Items]
Past due	3
Duke Energy Indiana | 60-90 days
Financing Receivable, Past Due [Line Items]
Past due	1
Duke Energy Indiana | 90+ days
Financing Receivable, Past Due [Line Items]
Past due	12
Piedmont
Financing Receivable, Past Due [Line Items]
Unbilled receivables	86	$ 78
Not past due	149
Deferred Payment Arrangements	7
Trade and Other Receivables	262
Piedmont | 30-60 days
Financing Receivable, Past Due [Line Items]
Past due	8
Piedmont | 60-90 days
Financing Receivable, Past Due [Line Items]
Past due	3
Piedmont | 90+ days
Financing Receivable, Past Due [Line Items]
Past due	$ 9

Revenue (Unbilled Revenues) (De

Revenue (Unbilled Revenues) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled receivables	$ 969	$ 843
Duke Energy Carolinas
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled receivables	328	298
Progress Energy
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled receivables	283	217
Duke Energy Progress
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled receivables	167	122
Duke Energy Florida
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled receivables	116	95
Duke Energy Ohio
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled receivables	2	1
Duke Energy Ohio | CRC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled receivables	87	82
Duke Energy Indiana
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled receivables	16	16
Duke Energy Indiana | CRC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled receivables	134	115
Piedmont
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled receivables	$ 86	$ 78

Stockholders' Equity (Earnings

Stockholders' Equity (Earnings Per Share Data) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Net Income available to Duke Energy common stockholders	$ 1,270	$ 3,707	$ 2,666
Income (Loss) From Discontinued Operations, net of tax	7	(7)	19
Accumulated preferred stock dividends adjustment	1	(15)	0
Less: Impact of participating securities	2	5	5
Income from continuing operations available to Duke Energy common stockholders	$ 1,262	$ 3,694	$ 2,642
Weighted average common shares outstanding – basic (in shares)	737	729	708
Equity forwards (in shares)	1	0	0
Weighted average common shares outstanding – diluted (in shares)	738	729	708
EPS from continuing operations available to Duke Energy common stockholders
Basic and diluted (usd per share)	$ 1.71	$ 5.07	$ 3.73
Potentially dilutive items excluded from the calculation(in shares)	2	2	2
Dividends declared per share (usd per share)	$ 3.82	$ 3.75	$ 3.64
Series A Preferred Stock
EPS from continuing operations available to Duke Energy common stockholders
Dividends declared on preferred stock (usd per share)	1.437	$ 1.03
Series B Preferred Stock
EPS from continuing operations available to Duke Energy common stockholders
Dividends declared on preferred stock (usd per share)	$ 49.292		$ 0

Stockholders' Equity (Common St

Stockholders' Equity (Common Stock) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Billions	1 Months Ended
	Dec. 31, 2020	Aug. 31, 2020	May 31, 2020	Mar. 31, 2020	Nov. 30, 2019
Forward Contract Indexed to Issuer's Equity [Line Items]
Maximum value of shares to be issued under ATM program					$ 1.5
Equity forwards
Forward Contract Indexed to Issuer's Equity [Line Items]
Shares offered		936	903	940	28,750
Forward Contract Indexed to Issuer's Equity, Forward Rate Per Share		$ 79.52	$ 82.44	$ 89.76	$ 85.99
Shares issued (in shares)	32,000
Proceeds from Issuance or Sale of Equity	$ 2.6

Stockholders' Equity (Preferred

Stockholders' Equity (Preferred Stock) (Details) - USD ($) $ / shares in Units, $ in Millions	Sep. 16, 2024	Sep. 12, 2019	Mar. 29, 2019	Dec. 31, 2019	Jun. 15, 2024	Dec. 31, 2020	Sep. 30, 2020
Class of Stock [Line Items]
Net proceeds from Issuance of Preferred Stock and Preference Stock		$ 989	$ 973	$ 1,962
Current maturities of long-term debt				$ 3,141		$ 4,238
Series A Cumulative Redeemable Perpetual Preferred Stock
Class of Stock [Line Items]
Shares issued (in shares)			40,000,000
Preferred stock, issue price (in usd per share)			$ 25
Liquidation preference per share (in usd per share)			$ 25
Cumulative annual dividend rate			5.75%
Redemption price (in usd per share)						$ 25.50
Series B Fixed-Rate Reset Cumulative Redeemable Perpetual Preferred Stock
Class of Stock [Line Items]
Shares issued (in shares)		1,000,000
Preferred stock, issue price (in usd per share)		$ 1,000
Liquidation preference per share (in usd per share)		$ 1,000
Cumulative annual dividend rate		4.875%
Redemption price (in usd per share)		$ 1,020
Forecast
Class of Stock [Line Items]
Redemption price (in usd per share)					$ 25
Forecast | Series B Fixed-Rate Reset Cumulative Redeemable Perpetual Preferred Stock
Class of Stock [Line Items]
Cumulative annual dividend rate	3.388%
Unsecured Debt | Senior notes due September 2019 | Parent Company
Class of Stock [Line Items]
Current maturities of long-term debt							$ 500

Severance (Narrative) (Details)

Severance (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)employee	Dec. 31, 2019USD ($)employee	Dec. 31, 2018employee
Restructuring Cost and Reserve [Line Items]
Regulatory assets	$ 14,062	$ 15,018
Number of eligible employees | employee	30	140	1,900
Duke Energy Progress
Restructuring Cost and Reserve [Line Items]
Regulatory assets	$ 4,468	$ 4,678
Duke Energy Progress | Employee Severance
Restructuring Cost and Reserve [Line Items]
Regulatory assets	33
Duke Energy Carolinas
Restructuring Cost and Reserve [Line Items]
Regulatory assets	3,469	$ 3,910
Duke Energy Carolinas | Employee Severance
Restructuring Cost and Reserve [Line Items]
Regulatory assets	$ 65

Severance (Expenses) (Details)

Severance (Expenses) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restructuring Cost and Reserve [Line Items]
Severance expense	$ (85)	$ 16	$ 187
Unamortized deferred severance	(86)
Severance charges adjustments	(6)
Duke Energy Carolinas
Restructuring Cost and Reserve [Line Items]
Severance expense	(58)	8	102
Unamortized deferred severance	(57)
Severance charges adjustments	(2)
Progress Energy
Restructuring Cost and Reserve [Line Items]
Severance expense	(28)	6	69
Unamortized deferred severance	(29)
Severance charges adjustments	(3)
Duke Energy Progress
Restructuring Cost and Reserve [Line Items]
Severance expense	(31)	3	52
Unamortized deferred severance	(29)
Severance charges adjustments	(2)
Duke Energy Florida
Restructuring Cost and Reserve [Line Items]
Severance expense	$ 3	3	17
Duke Energy Ohio
Restructuring Cost and Reserve [Line Items]
Severance expense			6
Duke Energy Indiana
Restructuring Cost and Reserve [Line Items]
Severance expense		1	7
Piedmont
Restructuring Cost and Reserve [Line Items]
Severance expense		$ 1	$ 2

Severance (Rollforward) (Detail

Severance (Rollforward) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)
Restructuring Reserve [Roll Forward]
Balance, beginning of period	$ 41
Provision/adjustments	1
Cash reductions	(31)
Balance, end of period	11
Duke Energy Carolinas
Restructuring Reserve [Roll Forward]
Balance, beginning of period	11
Cash reductions	(9)
Balance, end of period	2
Progress Energy
Restructuring Reserve [Roll Forward]
Balance, beginning of period	13
Cash reductions	(10)
Balance, end of period	3
Duke Energy Progress
Restructuring Reserve [Roll Forward]
Balance, beginning of period	6
Provision/adjustments	(2)
Cash reductions	(3)
Balance, end of period	1
Duke Energy Florida
Restructuring Reserve [Roll Forward]
Balance, beginning of period	7
Provision/adjustments	2
Cash reductions	(7)
Balance, end of period	2
Duke Energy Ohio
Restructuring Reserve [Roll Forward]
Balance, beginning of period	1
Provision/adjustments	(1)
Duke Energy Indiana
Restructuring Reserve [Roll Forward]
Balance, beginning of period	2
Cash reductions	(1)
Balance, end of period	$ 1

Stock-Based Compensation (Narra

Stock-Based Compensation (Narrative) (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for awards to employees and outside directors (in shares)	10
RSU awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total grant date fair value of shares vested	$ 43	$ 49	$ 43
Unrecognized compensation cost	$ 31
Unrecognized compensation cost, period of recognition, years	23 months
RSU awards | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Performance awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Total grant date fair value of shares vested	$ 36	$ 23
Unrecognized compensation cost	$ 23
Unrecognized compensation cost, period of recognition, years	21 months
Risk free interest rate	1.40%
Expected volatility rate	13.60%
Performance awards | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent	200.00%

Stock-Based Compensation (Sched

Stock-Based Compensation (Schedule of Stock-Based Compensation Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense recognized	$ 61	$ 65	$ 56
Pretax stock-based compensation cost	84	89	78
Stock-based compensation costs capitalized	5	5	5
Stock-based compensation expense	79	84	73
Tax benefit associated with stock-based compensation expense	18	19	17
RSU awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pretax stock-based compensation cost	46	44	43
Performance awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pretax stock-based compensation cost	38	45	35
Duke Energy Carolinas
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense recognized	22	24	20
Progress Energy
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense recognized	23	24	21
Duke Energy Progress
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense recognized	15	15	13
Duke Energy Florida
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense recognized	9	9	8
Duke Energy Ohio
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense recognized	4	5	4
Duke Energy Indiana
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense recognized	6	6	5
Piedmont
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense recognized	$ 3	$ 3	$ 3

Stock-Based Compensation (Summa

Stock-Based Compensation (Summary of Stock Awards Outstanding) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
RSU awards
Schedule Of Shares Awarded [Abstract]
Shares granted (in thousands)	498	571	649
Fair value (in millions)	$ 50	$ 51	$ 49
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding at beginning of period (in shares)	1,010
Granted (in shares)	498	571	649
Vested (in shares)	(532)
Forfeited (in shares)	(37)
Outstanding at end of period (in shares)	939	1,010
Stock awards expected to vest (in shares)	898
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Weighted average fair value at beginning of period (usd per share)	$ 83
Granted (usd per share)	100
Vested (usd per share)	82
Forfeited (usd per share)	92
Weighted average fair value at end of period (usd per share)	93	$ 83
Weighted average fair value of awards expected to vest (usd per share)	$ 93
Performance awards
Schedule Of Shares Awarded [Abstract]
Shares granted (in thousands)	319	320	372
Fair value (in millions)	$ 34	$ 27	$ 27
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding at beginning of period (in shares)	1,109
Granted (in shares)	319	320	372
Vested (in shares)	(448)
Forfeited (in shares)	(18)
Outstanding at end of period (in shares)	962	1,109
Stock awards expected to vest (in shares)	937
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Weighted average fair value at beginning of period (usd per share)	$ 80
Granted (usd per share)	105
Vested (usd per share)	81
Forfeited (usd per share)	88
Weighted average fair value at end of period (usd per share)	87	$ 80
Weighted average fair value of awards expected to vest (usd per share)	$ 87

Employee Benefit Plans (Narrati

Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2019
Defined Benefit Plan Disclosure [Line Items]
Maximum years of participation	35 years
Vesting period	3 years
Master Trust
Defined Benefit Plan Disclosure [Line Items]
Target allocation	100.00%
Expected long-term rate of return on plan assets	6.50%
Fair value of securities on loan	$ 482	$ 351
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 0	77	$ 141
Pension Plan | Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Average remaining service period, in years	13 years
Defined Benefit Plan, Benefit Obligation	$ 8,634	8,321	$ 7,869
Accumulated Benefit Obligation at measurement date	$ 8,577	$ 8,262
Expected long-term rate of return on plan assets	6.85%	6.85%	6.50%
Employer contributions		$ 77
Benefits paid	$ 541	731
Pension Plan | Nonqualified Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation	320
Accumulated Benefit Obligation at measurement date	320
Employer contributions	23
Benefits paid	$ 23
Pension Plan | Master Trust
Defined Benefit Plan Disclosure [Line Items]
Master trust allocation percentage	98.00%
Other Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Average remaining service period, in years	8 years
Defined Benefit Plan, Benefit Obligation	$ 709	$ 723	$ 728
Expected long-term rate of return on plan assets	6.85%	6.85%	6.50%
Employer contributions	$ 53
Benefits paid	$ 75	$ 83
Other Post-Retirement Benefit Plans | Master Trust
Defined Benefit Plan Disclosure [Line Items]
Master trust allocation percentage	2.00%
Duke Energy Carolinas | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 0	7	$ 46
Duke Energy Carolinas | Pension Plan | Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Average remaining service period, in years	12 years
Defined Benefit Plan, Benefit Obligation	$ 1,988	1,923	1,954
Accumulated Benefit Obligation at measurement date	1,989	1,923
Employer contributions		7
Benefits paid	137	265
Duke Energy Carolinas | Pension Plan | Nonqualified Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation	13
Accumulated Benefit Obligation at measurement date	13
Employer contributions	2
Benefits paid	$ 2
Duke Energy Carolinas | Other Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Average remaining service period, in years	8 years
Defined Benefit Plan, Benefit Obligation	$ 174	175	174
Employer contributions	10
Benefits paid	18	19
Progress Energy | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 0	57	45
Progress Energy | Pension Plan | Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Average remaining service period, in years	14 years
Defined Benefit Plan, Benefit Obligation	$ 2,715	2,608	2,433
Accumulated Benefit Obligation at measurement date	2,684	2,578
Employer contributions		57
Benefits paid	160	191
Progress Energy | Pension Plan | Nonqualified Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation	111
Accumulated Benefit Obligation at measurement date	111
Employer contributions	8
Benefits paid	$ 8
Progress Energy | Other Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Average remaining service period, in years	7 years
Defined Benefit Plan, Benefit Obligation	$ 299	303	303
Employer contributions	23
Benefits paid	28	32
Duke Energy Progress | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 0	4	25
Duke Energy Progress | Pension Plan | Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Average remaining service period, in years	14 years
Defined Benefit Plan, Benefit Obligation	$ 1,193	1,170	1,125
Accumulated Benefit Obligation at measurement date	1,194	1,170
Employer contributions		4
Benefits paid	83	112
Duke Energy Progress | Pension Plan | Nonqualified Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation	33
Accumulated Benefit Obligation at measurement date	33
Employer contributions	3
Benefits paid	$ 3
Duke Energy Progress | Other Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Average remaining service period, in years	6 years
Defined Benefit Plan, Benefit Obligation	$ 166	168	166
Employer contributions	11
Benefits paid	15	17
Duke Energy Florida | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 0	53	20
Duke Energy Florida | Pension Plan | Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Average remaining service period, in years	14 years
Defined Benefit Plan, Benefit Obligation	$ 1,507	1,424	1,295
Accumulated Benefit Obligation at measurement date	1,476	1,392
Employer contributions		53
Benefits paid	76	78
Duke Energy Florida | Pension Plan | Nonqualified Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation	45
Accumulated Benefit Obligation at measurement date	45
Employer contributions	3
Benefits paid	$ 3
Duke Energy Florida | Other Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Average remaining service period, in years	7 years
Defined Benefit Plan, Benefit Obligation	$ 130	135	137
Employer contributions	10
Benefits paid	13	15
Duke Energy Ohio | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 0	2	0
Duke Energy Ohio | Pension Plan | Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Average remaining service period, in years	13 years
Defined Benefit Plan, Benefit Obligation	$ 502	481	435
Accumulated Benefit Obligation at measurement date	493	471
Employer contributions		2
Benefits paid	34	30
Duke Energy Ohio | Pension Plan | Nonqualified Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation	4
Accumulated Benefit Obligation at measurement date	$ 4
Duke Energy Ohio | Other Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Average remaining service period, in years	7 years
Defined Benefit Plan, Benefit Obligation	$ 27	29	29
Employer contributions	3
Benefits paid	4	3
Duke Energy Indiana | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 0	2	8
Duke Energy Indiana | Pension Plan | Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Average remaining service period, in years	13 years
Defined Benefit Plan, Benefit Obligation	$ 715	693	618
Accumulated Benefit Obligation at measurement date	709	686
Employer contributions		2
Benefits paid	49	46
Duke Energy Indiana | Pension Plan | Nonqualified Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation	2
Accumulated Benefit Obligation at measurement date	$ 2
Duke Energy Indiana | Other Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Average remaining service period, in years	6 years
Defined Benefit Plan, Benefit Obligation	$ 61	64	67
Employer contributions	8
Benefits paid	$ 9	11
Piedmont
Defined Benefit Plan Disclosure [Line Items]
Term	3 years
Piedmont | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 0	1	0
Piedmont | Pension Plan | Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Average remaining service period, in years	9 years
Defined Benefit Plan, Benefit Obligation	$ 293	292	264
Accumulated Benefit Obligation at measurement date	294	292
Employer contributions		1
Benefits paid	27	20
Piedmont | Pension Plan | Nonqualified Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation	4
Accumulated Benefit Obligation at measurement date	$ 4
Piedmont | Other Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Average remaining service period, in years	6 years
Defined Benefit Plan, Benefit Obligation	$ 30	30	$ 30
Employer contributions	1
Benefits paid	$ 2	1
Liability Hedging Assets | Pension Plan | Master Trust
Defined Benefit Plan Disclosure [Line Items]
Target allocation				58.00%
Return Seeking Assets | Pension Plan | Master Trust
Defined Benefit Plan Disclosure [Line Items]
Target allocation				42.00%
Minimum | Pension Plan | Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Expected long-term rate of return on plan assets
Retirement plan settled
Defined Benefit Plan Disclosure [Line Items]
Settlement charges		94
Retirement plan settled | Duke Energy Carolinas
Defined Benefit Plan Disclosure [Line Items]
Settlement charges		53
Retirement plan settled | Progress Energy
Defined Benefit Plan Disclosure [Line Items]
Settlement charges		26
Retirement plan settled | Duke Energy Progress
Defined Benefit Plan Disclosure [Line Items]
Settlement charges		20
Retirement plan settled | Duke Energy Florida
Defined Benefit Plan Disclosure [Line Items]
Settlement charges		6
Retirement plan settled | Duke Energy Ohio
Defined Benefit Plan Disclosure [Line Items]
Settlement charges		2
Retirement plan settled | Duke Energy Indiana
Defined Benefit Plan Disclosure [Line Items]
Settlement charges		4
Retirement plan settled | Piedmont
Defined Benefit Plan Disclosure [Line Items]
Settlement charges		$ 8

Employee Benefit Plans (Contrib

Employee Benefit Plans (Contributions to Defined Benefit Pension Plans) (Details) - Pension Plan - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 0	$ 77	$ 141
Duke Energy Carolinas
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	0	7	46
Progress Energy
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	0	57	45
Duke Energy Progress
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	0	4	25
Duke Energy Florida
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	0	53	20
Duke Energy Ohio
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	0	2	0
Duke Energy Indiana
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	0	2	8
Piedmont
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 0	$ 1	$ 0

Employee Benefit Plans (Compone

Employee Benefit Plans (Components of Net Periodic Pension Costs) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pension Plan
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Amortization of regulatory asset	$ 4	$ 4	$ 5
Pension Plan | Qualified Plan
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	165	158
Service cost	157	150	182
Interest cost	269	317	299
Expected return on plan assets	(572)	(567)	(559)
Amortization of prior service credit	128	108	132
Amortization of prior service cost (credit)	(32)	(32)	(32)
Amortization of settlement charges	18	6
Net periodic costs	(24)	(10)	22
Pension Plan | Duke Energy Carolinas | Qualified Plan
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	51	49
Service cost	49	47	58
Interest cost	62	75	72
Expected return on plan assets	(145)	(147)	(147)
Amortization of prior service credit	28	24	29
Amortization of prior service cost (credit)	(8)	(8)	(8)
Amortization of settlement charges	9	2
Net periodic costs	(3)	(5)	4
Pension Plan | Progress Energy | Qualified Plan
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	48	46
Service cost	46	43	51
Interest cost	85	100	94
Expected return on plan assets	(190)	(178)	(178)
Amortization of prior service credit	41	39	44
Amortization of prior service cost (credit)	(3)	(3)	(3)
Amortization of settlement charges	7	1
Net periodic costs	(12)	5	8
Pension Plan | Duke Energy Progress | Qualified Plan
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	27	26
Service cost	26	25	29
Interest cost	38	45	43
Expected return on plan assets	(87)	(88)	(85)
Amortization of prior service credit	18	15	21
Amortization of prior service cost (credit)	(2)	(2)	(2)
Amortization of settlement charges	6	1
Net periodic costs	0	(3)	6
Pension Plan | Duke Energy Florida | Qualified Plan
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	21	20
Service cost	20	18	22
Interest cost	46	54	50
Expected return on plan assets	(101)	(89)	(91)
Amortization of prior service credit	23	24	23
Amortization of prior service cost (credit)	(1)	(1)	(1)
Amortization of settlement charges	1	0
Net periodic costs	(11)	8	3
Pension Plan | Duke Energy Ohio
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Amortization of regulatory asset	2	2	2
Pension Plan | Duke Energy Ohio | Qualified Plan
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	5	4
Service cost	4	4	5
Interest cost	15	18	17
Expected return on plan assets	(28)	(28)	(28)
Amortization of prior service credit	6	4	5
Amortization of prior service cost (credit)	0	0	0
Amortization of settlement charges	0	2
Net periodic costs	(2)	0	(1)
Pension Plan | Duke Energy Indiana | Qualified Plan
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	9	9
Service cost	8	8	11
Interest cost	22	26	23
Expected return on plan assets	(42)	(43)	(42)
Amortization of prior service credit	12	8	10
Amortization of prior service cost (credit)	(2)	(2)	(2)
Amortization of settlement charges	1	0
Net periodic costs	0	(2)	0
Pension Plan | Piedmont | Qualified Plan
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	6	5
Service cost	5	5	7
Interest cost	9	10	11
Expected return on plan assets	(21)	(22)	(22)
Amortization of prior service credit	9	8	11
Amortization of prior service cost (credit)	(9)	(9)	(10)
Amortization of settlement charges	1	0
Net periodic costs	(5)	(8)	(3)
Other Post-Retirement Benefit Plans
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	4	4	6
Interest cost	23	30	28
Expected return on plan assets	(13)	(12)	(13)
Amortization of prior service credit	2	4	6
Amortization of prior service cost (credit)	(14)	(19)	(19)
Net periodic costs	2	7	8
Amortization of regulatory asset	6	6	7
Other Post-Retirement Benefit Plans | Duke Energy Carolinas
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	1	1	1
Interest cost	5	7	7
Expected return on plan assets	(8)	(7)	(8)
Amortization of prior service credit	0	2	3
Amortization of prior service cost (credit)	(4)	(5)	(5)
Net periodic costs	(6)	(2)	(2)
Other Post-Retirement Benefit Plans | Progress Energy
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	1	1	1
Interest cost	10	12	12
Expected return on plan assets	0	0	0
Amortization of prior service credit	1	1	1
Amortization of prior service cost (credit)	(3)	(8)	(8)
Net periodic costs	9	6	6
Other Post-Retirement Benefit Plans | Duke Energy Progress
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	0	0	0
Interest cost	5	7	6
Expected return on plan assets	0	0	0
Amortization of prior service credit	0	0	1
Amortization of prior service cost (credit)	(1)	(1)	(1)
Net periodic costs	4	6	6
Other Post-Retirement Benefit Plans | Duke Energy Florida
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	0	1	1
Interest cost	4	5	6
Expected return on plan assets	0	0	0
Amortization of prior service credit	1	1	0
Amortization of prior service cost (credit)	(2)	(7)	(7)
Net periodic costs	3	0	0
Other Post-Retirement Benefit Plans | Duke Energy Ohio
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	0	0	1
Interest cost	1	1	1
Expected return on plan assets	0	0	0
Amortization of prior service credit	0	0	0
Amortization of prior service cost (credit)	(1)	(1)	(1)
Net periodic costs	0	0	1
Amortization of regulatory asset	1	2	2
Other Post-Retirement Benefit Plans | Duke Energy Indiana
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	1	1	1
Interest cost	2	3	3
Expected return on plan assets	0	0	0
Amortization of prior service credit	4	4	4
Amortization of prior service cost (credit)	(1)	(1)	(1)
Net periodic costs	6	7	7
Other Post-Retirement Benefit Plans | Piedmont
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	0	0	1
Interest cost	1	1	1
Expected return on plan assets	(2)	(1)	(2)
Amortization of prior service credit	0	0	0
Amortization of prior service cost (credit)	(2)	(2)	(2)
Net periodic costs	$ (3)	$ (2)	$ (2)

Employee Benefit Plans (Amounts

Employee Benefit Plans (Amounts Recognized in Accumulated Other Comprehensive Income and Regulatory Assets and Liabilities) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Net amount recognized in accumulated other comprehensive income	[1]	$ (6)	$ (9)	$ 6
Progress Energy
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Net amount recognized in accumulated other comprehensive income		1	(2)	$ (5)
Pension Plan | Qualified Plan
Amounts Recognized in Regulatory Assets and Liabilities [Abstract]
Regulatory assets, net increase (decrease)		(62)	(212)
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Deferred income tax expense (benefit)		2	20
Amortization of prior year service credit		1	1
Amortization of prior year actuarial losses		(11)	(15)
Net amount recognized in accumulated other comprehensive income		(8)	6
Pension Plan | Duke Energy Carolinas | Qualified Plan
Amounts Recognized in Regulatory Assets and Liabilities [Abstract]
Regulatory assets, net increase (decrease)		(39)	(156)
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Deferred income tax expense (benefit)		0	0
Amortization of prior year service credit		0	0
Amortization of prior year actuarial losses		0	0
Net amount recognized in accumulated other comprehensive income		0	0
Pension Plan | Progress Energy | Qualified Plan
Amounts Recognized in Regulatory Assets and Liabilities [Abstract]
Regulatory assets, net increase (decrease)		(26)	(79)
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Deferred income tax expense (benefit)		1	1
Amortization of prior year service credit		0	0
Amortization of prior year actuarial losses		(1)	(2)
Net amount recognized in accumulated other comprehensive income		0	(1)
Pension Plan | Duke Energy Progress | Qualified Plan
Amounts Recognized in Regulatory Assets and Liabilities [Abstract]
Regulatory assets, net increase (decrease)		(30)	(59)
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Deferred income tax expense (benefit)		0	0
Amortization of prior year service credit		0	0
Amortization of prior year actuarial losses		0	0
Net amount recognized in accumulated other comprehensive income		0	0
Pension Plan | Duke Energy Florida | Qualified Plan
Amounts Recognized in Regulatory Assets and Liabilities [Abstract]
Regulatory assets, net increase (decrease)		4	(20)
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Deferred income tax expense (benefit)		1	(1)
Amortization of prior year service credit		0	0
Amortization of prior year actuarial losses		(3)	3
Net amount recognized in accumulated other comprehensive income		(2)	2
Pension Plan | Duke Energy Ohio | Qualified Plan
Amounts Recognized in Regulatory Assets and Liabilities [Abstract]
Regulatory assets, net increase (decrease)		(2)	12
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Deferred income tax expense (benefit)		0	0
Amortization of prior year service credit		0	0
Amortization of prior year actuarial losses		0	0
Net amount recognized in accumulated other comprehensive income		0	0
Pension Plan | Duke Energy Indiana | Qualified Plan
Amounts Recognized in Regulatory Assets and Liabilities [Abstract]
Regulatory assets, net increase (decrease)		5	22
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Deferred income tax expense (benefit)		0	0
Amortization of prior year service credit		0	0
Amortization of prior year actuarial losses		0	0
Net amount recognized in accumulated other comprehensive income		0	0
Pension Plan | Piedmont | Qualified Plan
Amounts Recognized in Regulatory Assets and Liabilities [Abstract]
Regulatory assets, net increase (decrease)		(1)	0
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Deferred income tax expense (benefit)		0	0
Amortization of prior year service credit		0	0
Amortization of prior year actuarial losses		0	0
Net amount recognized in accumulated other comprehensive income		0	0
Other Post-Retirement Benefit Plans
Amounts Recognized in Regulatory Assets and Liabilities [Abstract]
Regulatory assets, net increase (decrease)		9	(127)
Regulatory liabilities, net increase (decrease)		(10)	(152)
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Deferred income tax expense (benefit)		0	0
Amortization of prior year actuarial gain		(1)	4
Net amount recognized in accumulated other comprehensive income		1	(4)
Other Post-Retirement Benefit Plans | Duke Energy Carolinas
Amounts Recognized in Regulatory Assets and Liabilities [Abstract]
Regulatory assets, net increase (decrease)		0	0
Regulatory liabilities, net increase (decrease)		(7)	1
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Deferred income tax expense (benefit)		0	0
Amortization of prior year actuarial gain		0	0
Net amount recognized in accumulated other comprehensive income		0	0
Other Post-Retirement Benefit Plans | Progress Energy
Amounts Recognized in Regulatory Assets and Liabilities [Abstract]
Regulatory assets, net increase (decrease)		9	(127)
Regulatory liabilities, net increase (decrease)		0	(149)
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Deferred income tax expense (benefit)		0	0
Amortization of prior year actuarial gain		0	0
Net amount recognized in accumulated other comprehensive income		0	0
Other Post-Retirement Benefit Plans | Duke Energy Progress
Amounts Recognized in Regulatory Assets and Liabilities [Abstract]
Regulatory assets, net increase (decrease)		6	(82)
Regulatory liabilities, net increase (decrease)		0	(93)
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Deferred income tax expense (benefit)		0	0
Amortization of prior year actuarial gain		0	0
Net amount recognized in accumulated other comprehensive income		0	0
Other Post-Retirement Benefit Plans | Duke Energy Florida
Amounts Recognized in Regulatory Assets and Liabilities [Abstract]
Regulatory assets, net increase (decrease)		3	(45)
Regulatory liabilities, net increase (decrease)		0	(56)
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Deferred income tax expense (benefit)		0	0
Amortization of prior year actuarial gain		0	0
Net amount recognized in accumulated other comprehensive income		0	0
Other Post-Retirement Benefit Plans | Duke Energy Ohio
Amounts Recognized in Regulatory Assets and Liabilities [Abstract]
Regulatory assets, net increase (decrease)		0	0
Regulatory liabilities, net increase (decrease)		0	(1)
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Deferred income tax expense (benefit)		0	0
Amortization of prior year actuarial gain		0	0
Net amount recognized in accumulated other comprehensive income		0	0
Other Post-Retirement Benefit Plans | Duke Energy Indiana
Amounts Recognized in Regulatory Assets and Liabilities [Abstract]
Regulatory assets, net increase (decrease)		(4)	(5)
Regulatory liabilities, net increase (decrease)		(1)	(4)
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Deferred income tax expense (benefit)		0	0
Amortization of prior year actuarial gain		0	0
Net amount recognized in accumulated other comprehensive income		0	0
Other Post-Retirement Benefit Plans | Piedmont
Amounts Recognized in Regulatory Assets and Liabilities [Abstract]
Regulatory assets, net increase (decrease)		0	0
Regulatory liabilities, net increase (decrease)		0	3
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) [Abstract]
Deferred income tax expense (benefit)		0	0
Amortization of prior year actuarial gain		0	0
Net amount recognized in accumulated other comprehensive income		$ 0	$ 0
[1]	Net of income tax impacts of approximately $35 million for the year ended December 31, 2020. Tax impacts are immaterial for other periods presented.

Employee Benefit Plans (Project

Employee Benefit Plans (Projected Benefit Obligations Reconciliation of Funded Status to Net Amount Recognized) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pension Plan
Change in Fair Value of Plan Assets [Rollforward]
Employer contributions	$ 0	$ 77	$ 141
Pension Plan | Duke Energy Carolinas
Change in Fair Value of Plan Assets [Rollforward]
Employer contributions	0	7	46
Pension Plan | Progress Energy
Change in Fair Value of Plan Assets [Rollforward]
Employer contributions	0	57	45
Pension Plan | Duke Energy Progress
Change in Fair Value of Plan Assets [Rollforward]
Employer contributions	0	4	25
Pension Plan | Duke Energy Florida
Change in Fair Value of Plan Assets [Rollforward]
Employer contributions	0	53	20
Pension Plan | Duke Energy Ohio
Change in Fair Value of Plan Assets [Rollforward]
Employer contributions	0	2	0
Pension Plan | Duke Energy Indiana
Change in Fair Value of Plan Assets [Rollforward]
Employer contributions	0	2	8
Pension Plan | Piedmont
Change in Fair Value of Plan Assets [Rollforward]
Employer contributions	0	1	0
Pension Plan | Qualified Plan
Change in Projected Benefit Obligation [Rollforward]
Obligation at prior measurement date	8,321	7,869
Service cost	157	150	182
Interest cost	269	317	299
Actuarial loss	433	716
Transfers	0	0
Benefits paid	(541)	(731)
Benefits paid – settlements	(5)
Obligation at measurement date	8,634	8,321	7,869
Accumulated Benefit Obligation at measurement date	8,577	8,262
Change in Fair Value of Plan Assets [Rollforward]
Plan assets at prior measurement date	8,910	8,233
Employer contributions		77
Actual return on plan assets	973	1,331
Benefits paid	(541)	(731)
Benefits paid – settlements	(5)
Transfers	0	0
Plan assets at measurement date	9,337	8,910	8,233
Funded status of plan	703	589
Pension Plan | Qualified Plan | Duke Energy Carolinas
Change in Projected Benefit Obligation [Rollforward]
Obligation at prior measurement date	1,923	1,954
Service cost	49	47	58
Interest cost	62	75	72
Actuarial loss	83	101
Transfers	8	11
Benefits paid	(137)	(265)
Benefits paid – settlements	0
Obligation at measurement date	1,988	1,923	1,954
Accumulated Benefit Obligation at measurement date	1,989	1,923
Change in Fair Value of Plan Assets [Rollforward]
Plan assets at prior measurement date	2,263	2,168
Employer contributions		7
Actual return on plan assets	247	342
Benefits paid	(137)	(265)
Benefits paid – settlements	0
Transfers	8	11
Plan assets at measurement date	2,381	2,263	2,168
Funded status of plan	393	340
Pension Plan | Qualified Plan | Progress Energy
Change in Projected Benefit Obligation [Rollforward]
Obligation at prior measurement date	2,608	2,433
Service cost	46	43	51
Interest cost	85	100	94
Actuarial loss	144	223
Transfers	(8)	0
Benefits paid	(160)	(191)
Benefits paid – settlements	0
Obligation at measurement date	2,715	2,608	2,433
Accumulated Benefit Obligation at measurement date	2,684	2,578
Change in Fair Value of Plan Assets [Rollforward]
Plan assets at prior measurement date	2,898	2,606
Employer contributions		57
Actual return on plan assets	319	426
Benefits paid	(160)	(191)
Benefits paid – settlements	0
Transfers	(8)	0
Plan assets at measurement date	3,049	2,898	2,606
Funded status of plan	334	290
Pension Plan | Qualified Plan | Duke Energy Progress
Change in Projected Benefit Obligation [Rollforward]
Obligation at prior measurement date	1,170	1,125
Service cost	26	25	29
Interest cost	38	45	43
Actuarial loss	50	87
Transfers	(8)	0
Benefits paid	(83)	(112)
Benefits paid – settlements	0
Obligation at measurement date	1,193	1,170	1,125
Accumulated Benefit Obligation at measurement date	1,194	1,170
Change in Fair Value of Plan Assets [Rollforward]
Plan assets at prior measurement date	1,364	1,268
Employer contributions		4
Actual return on plan assets	149	204
Benefits paid	(83)	(112)
Benefits paid – settlements	0
Transfers	(8)	0
Plan assets at measurement date	1,422	1,364	1,268
Funded status of plan	229	194
Pension Plan | Qualified Plan | Duke Energy Florida
Change in Projected Benefit Obligation [Rollforward]
Obligation at prior measurement date	1,424	1,295
Service cost	20	18	22
Interest cost	46	54	50
Actuarial loss	93	135
Transfers	0	0
Benefits paid	(76)	(78)
Benefits paid – settlements	0
Obligation at measurement date	1,507	1,424	1,295
Accumulated Benefit Obligation at measurement date	1,476	1,392
Change in Fair Value of Plan Assets [Rollforward]
Plan assets at prior measurement date	1,515	1,322
Employer contributions		53
Actual return on plan assets	166	218
Benefits paid	(76)	(78)
Benefits paid – settlements	0
Transfers	0	0
Plan assets at measurement date	1,605	1,515	1,322
Funded status of plan	98	91
Pension Plan | Qualified Plan | Duke Energy Ohio
Change in Projected Benefit Obligation [Rollforward]
Obligation at prior measurement date	481	435
Service cost	4	4	5
Interest cost	15	18	17
Actuarial loss	21	54
Transfers	15	0
Benefits paid	(34)	(30)
Benefits paid – settlements	0
Obligation at measurement date	502	481	435
Accumulated Benefit Obligation at measurement date	493	471
Change in Fair Value of Plan Assets [Rollforward]
Plan assets at prior measurement date	443	405
Employer contributions		2
Actual return on plan assets	48	66
Benefits paid	(34)	(30)
Benefits paid – settlements	0
Transfers	15	0
Plan assets at measurement date	472	443	405
Funded status of plan	(30)	(38)
Pension Plan | Qualified Plan | Duke Energy Indiana
Change in Projected Benefit Obligation [Rollforward]
Obligation at prior measurement date	693	618
Service cost	8	8	11
Interest cost	22	26	23
Actuarial loss	46	87
Transfers	0	0
Benefits paid	(49)	(46)
Benefits paid – settlements	(5)
Obligation at measurement date	715	693	618
Accumulated Benefit Obligation at measurement date	709	686
Change in Fair Value of Plan Assets [Rollforward]
Plan assets at prior measurement date	667	611
Employer contributions		2
Actual return on plan assets	71	100
Benefits paid	(49)	(46)
Benefits paid – settlements	(5)
Transfers	0	0
Plan assets at measurement date	684	667	611
Funded status of plan	(31)	(26)
Pension Plan | Qualified Plan | Piedmont
Change in Projected Benefit Obligation [Rollforward]
Obligation at prior measurement date	292	264
Service cost	5	5	7
Interest cost	9	10	11
Actuarial loss	14	33
Transfers	0	0
Benefits paid	(27)	(20)
Benefits paid – settlements	0
Obligation at measurement date	293	292	264
Accumulated Benefit Obligation at measurement date	294	292
Change in Fair Value of Plan Assets [Rollforward]
Plan assets at prior measurement date	335	305
Employer contributions		1
Actual return on plan assets	35	49
Benefits paid	(27)	(20)
Benefits paid – settlements	0
Transfers	0	0
Plan assets at measurement date	343	335	305
Funded status of plan	50	43
Other Post-Retirement Benefit Plans
Change in Projected Benefit Obligation [Rollforward]
Obligation at prior measurement date	723	728
Service cost	4	4	6
Interest cost	23	30	28
Plan participants' contributions	15	16
Actuarial loss	19	28
Benefits paid	(75)	(83)
Obligation at measurement date	709	723	728
Change in Fair Value of Plan Assets [Rollforward]
Plan assets at prior measurement date	220	195
Employer contributions	53
Actual return on plan assets	24	32
Benefits paid	(75)	(83)
Plan participants' contributions	15	16
Employer contributions		60
Plan assets at measurement date	237	220	195
Funded status of plan	(472)	(503)
Other Post-Retirement Benefit Plans | Duke Energy Carolinas
Change in Projected Benefit Obligation [Rollforward]
Obligation at prior measurement date	175	174
Service cost	1	1	1
Interest cost	5	7	7
Plan participants' contributions	3	3
Actuarial loss	8	9
Benefits paid	(18)	(19)
Obligation at measurement date	174	175	174
Change in Fair Value of Plan Assets [Rollforward]
Plan assets at prior measurement date	130	115
Employer contributions	10
Actual return on plan assets	14	20
Benefits paid	(18)	(19)
Plan participants' contributions	3	3
Employer contributions		11
Plan assets at measurement date	139	130	115
Funded status of plan	(35)	(45)
Other Post-Retirement Benefit Plans | Progress Energy
Change in Projected Benefit Obligation [Rollforward]
Obligation at prior measurement date	303	303
Service cost	1	1	1
Interest cost	10	12	12
Plan participants' contributions	5	6
Actuarial loss	8	13
Benefits paid	(28)	(32)
Obligation at measurement date	299	303	303
Change in Fair Value of Plan Assets [Rollforward]
Plan assets at prior measurement date	(1)	0
Employer contributions	23
Actual return on plan assets	0	(1)
Benefits paid	(28)	(32)
Plan participants' contributions	5	6
Employer contributions		26
Plan assets at measurement date	(1)	(1)	0
Funded status of plan	(300)	(304)
Other Post-Retirement Benefit Plans | Duke Energy Progress
Change in Projected Benefit Obligation [Rollforward]
Obligation at prior measurement date	168	166
Service cost	0	0	0
Interest cost	5	7	6
Plan participants' contributions	3	3
Actuarial loss	5	9
Benefits paid	(15)	(17)
Obligation at measurement date	166	168	166
Change in Fair Value of Plan Assets [Rollforward]
Plan assets at prior measurement date	(1)	0
Employer contributions	11
Actual return on plan assets	0	0
Benefits paid	(15)	(17)
Plan participants' contributions	3	3
Employer contributions		13
Plan assets at measurement date	(2)	(1)	0
Funded status of plan	(168)	(169)
Other Post-Retirement Benefit Plans | Duke Energy Florida
Change in Projected Benefit Obligation [Rollforward]
Obligation at prior measurement date	135	137
Service cost	0	1	1
Interest cost	4	5	6
Plan participants' contributions	2	2
Actuarial loss	2	5
Benefits paid	(13)	(15)
Obligation at measurement date	130	135	137
Change in Fair Value of Plan Assets [Rollforward]
Plan assets at prior measurement date	0	0
Employer contributions	10
Actual return on plan assets	0	0
Benefits paid	(13)	(15)
Plan participants' contributions	2	2
Employer contributions		13
Plan assets at measurement date	(1)	0	0
Funded status of plan	(131)	(135)
Other Post-Retirement Benefit Plans | Duke Energy Ohio
Change in Projected Benefit Obligation [Rollforward]
Obligation at prior measurement date	29	29
Service cost	0	0	1
Interest cost	1	1	1
Plan participants' contributions	1	1
Actuarial loss	0	1
Benefits paid	(4)	(3)
Obligation at measurement date	27	29	29
Change in Fair Value of Plan Assets [Rollforward]
Plan assets at prior measurement date	9	8
Employer contributions	3
Actual return on plan assets	0	1
Benefits paid	(4)	(3)
Plan participants' contributions	1	1
Employer contributions		2
Plan assets at measurement date	9	9	8
Funded status of plan	(18)	(20)
Other Post-Retirement Benefit Plans | Duke Energy Indiana
Change in Projected Benefit Obligation [Rollforward]
Obligation at prior measurement date	64	67
Service cost	1	1	1
Interest cost	2	3	3
Plan participants' contributions	2	2
Actuarial loss	1	2
Benefits paid	(9)	(11)
Obligation at measurement date	61	64	67
Change in Fair Value of Plan Assets [Rollforward]
Plan assets at prior measurement date	5	5
Employer contributions	8
Actual return on plan assets	1	0
Benefits paid	(9)	(11)
Plan participants' contributions	2	2
Employer contributions		9
Plan assets at measurement date	7	5	5
Funded status of plan	(54)	(59)
Other Post-Retirement Benefit Plans | Piedmont
Change in Projected Benefit Obligation [Rollforward]
Obligation at prior measurement date	30	30
Service cost	0	0	1
Interest cost	1	1	1
Plan participants' contributions	0	0
Actuarial loss	1	0
Benefits paid	(2)	(1)
Obligation at measurement date	30	30	30
Change in Fair Value of Plan Assets [Rollforward]
Plan assets at prior measurement date	34	29
Employer contributions	1
Actual return on plan assets	4	6
Benefits paid	(2)	(1)
Plan participants' contributions	0	0
Employer contributions		0
Plan assets at measurement date	37	34	$ 29
Funded status of plan	$ 7	$ 4

Employee Benefit Plans (Amoun_2

Employee Benefit Plans (Amounts Recognized in Consolidated Balance Sheets) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	$ 969	$ 934
Regulatory assets	14,062	15,018
Regulatory liabilities	16,406	16,048
Duke Energy Carolinas
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	73	84
Regulatory assets	3,469	3,910
Regulatory liabilities	7,008	6,678
Progress Energy
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	505	488
Regulatory assets	6,533	7,292
Regulatory liabilities	5,691	5,555
Duke Energy Progress
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	242	238
Regulatory assets	4,468	4,678
Regulatory liabilities	4,924	4,468
Duke Energy Florida
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	231	218
Regulatory assets	2,064	2,613
Regulatory liabilities	768	1,087
Duke Energy Ohio
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	113	100
Regulatory assets	649	598
Regulatory liabilities	813	827
Duke Energy Indiana
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	171	148
Regulatory assets	1,328	1,172
Regulatory liabilities	1,738	1,740
Piedmont
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	8	3
Regulatory assets	455	363
Regulatory liabilities	1,132	1,212
Pension Plan | Qualified Plan
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	780	621
Noncurrent pension liability	77	32
Net amount recognized	703	589
Regulatory assets	1,910	1,972
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax asset	(21)	(23)
Prior year service cost (credit) arising during the year	(2)	(3)
Net actuarial loss (gain)	100	111
Net amount recognized in accumulated other comprehensive income (loss)	77	85
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss		135
Unrecognized prior service (credit) cost		(32)
Pension Plan | Duke Energy Carolinas | Qualified Plan
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	393	340
Noncurrent pension liability	0	0
Net amount recognized	393	340
Regulatory assets	381	420
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax asset	0	0
Prior year service cost (credit) arising during the year	0	0
Net actuarial loss (gain)	0	0
Net amount recognized in accumulated other comprehensive income (loss)	0	0
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss		29
Unrecognized prior service (credit) cost		(8)
Pension Plan | Progress Energy | Qualified Plan
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	379	322
Noncurrent pension liability	45	32
Net amount recognized	334	290
Regulatory assets	691	717
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax asset	0	(1)
Prior year service cost (credit) arising during the year	0	0
Net actuarial loss (gain)	2	3
Net amount recognized in accumulated other comprehensive income (loss)	2	2
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss		43
Unrecognized prior service (credit) cost		(3)
Pension Plan | Duke Energy Progress | Qualified Plan
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	229	194
Noncurrent pension liability	0	0
Net amount recognized	229	194
Regulatory assets	283	313
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax asset	0	0
Prior year service cost (credit) arising during the year	0	0
Net actuarial loss (gain)	0	0
Net amount recognized in accumulated other comprehensive income (loss)	0	0
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss		19
Unrecognized prior service (credit) cost		(2)
Pension Plan | Duke Energy Florida | Qualified Plan
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	143	123
Noncurrent pension liability	45	32
Net amount recognized	98	91
Regulatory assets	408	404
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax asset	0	(1)
Prior year service cost (credit) arising during the year	0	0
Net actuarial loss (gain)	0	3
Net amount recognized in accumulated other comprehensive income (loss)	0	2
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss		24
Unrecognized prior service (credit) cost		(1)
Pension Plan | Duke Energy Ohio | Qualified Plan
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	58	38
Noncurrent pension liability	88	76
Net amount recognized	(30)	(38)
Regulatory assets	110	112
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax asset	0	0
Prior year service cost (credit) arising during the year	0	0
Net actuarial loss (gain)	0	0
Net amount recognized in accumulated other comprehensive income (loss)	0	0
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss		7
Unrecognized prior service (credit) cost		(1)
Pension Plan | Duke Energy Indiana | Qualified Plan
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	79	57
Noncurrent pension liability	110	83
Net amount recognized	(31)	(26)
Regulatory assets	209	204
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax asset	0	0
Prior year service cost (credit) arising during the year	0	0
Net actuarial loss (gain)	0	0
Net amount recognized in accumulated other comprehensive income (loss)	0	0
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss		10
Unrecognized prior service (credit) cost		(2)
Pension Plan | Piedmont | Qualified Plan
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	50	43
Noncurrent pension liability	0	0
Net amount recognized	50	43
Regulatory assets	80	81
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax asset	0	0
Prior year service cost (credit) arising during the year	0	0
Net actuarial loss (gain)	0	0
Net amount recognized in accumulated other comprehensive income (loss)	0	0
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss		9
Unrecognized prior service (credit) cost		(9)
Other Post-Retirement Benefit Plans
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	8
Current pension liability	9	9
Noncurrent pension liability	471	494
Net amount recognized	(472)
Total accrued pension liability		503
Regulatory assets	144	135
Regulatory liabilities	139	149
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax liability	3	3
Prior year service cost (credit) arising during the year	(1)	(2)
Net actuarial loss (gain)	(13)	(13)
Net amount recognized in accumulated other comprehensive income (loss)	(11)	(12)
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss		5
Unrecognized prior service (credit) cost		(14)
Other Post-Retirement Benefit Plans | Duke Energy Carolinas
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	0
Current pension liability	0	0
Noncurrent pension liability	35	45
Net amount recognized	(35)
Total accrued pension liability		45
Regulatory assets	0	0
Regulatory liabilities	32	39
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax liability	0	0
Prior year service cost (credit) arising during the year	0	0
Net actuarial loss (gain)	0	0
Net amount recognized in accumulated other comprehensive income (loss)	0	0
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss		3
Unrecognized prior service (credit) cost		(4)
Other Post-Retirement Benefit Plans | Progress Energy
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	0
Current pension liability	6	5
Noncurrent pension liability	294	299
Net amount recognized	(300)
Total accrued pension liability		304
Regulatory assets	144	135
Regulatory liabilities	0	0
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax liability	0	0
Prior year service cost (credit) arising during the year	0	0
Net actuarial loss (gain)	0	0
Net amount recognized in accumulated other comprehensive income (loss)	0	0
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss		1
Unrecognized prior service (credit) cost		(3)
Other Post-Retirement Benefit Plans | Duke Energy Progress
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	0
Current pension liability	4	3
Noncurrent pension liability	164	163
Net amount recognized	(168)
Total accrued pension liability		166
Regulatory assets	88	82
Regulatory liabilities	0	0
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax liability	0	0
Prior year service cost (credit) arising during the year	0	0
Net actuarial loss (gain)	0	0
Net amount recognized in accumulated other comprehensive income (loss)	0	0
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss		0
Unrecognized prior service (credit) cost		(1)
Other Post-Retirement Benefit Plans | Duke Energy Florida
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	0
Current pension liability	2	2
Noncurrent pension liability	129	133
Net amount recognized	(131)
Total accrued pension liability		135
Regulatory assets	56	53
Regulatory liabilities	0	0
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax liability	0	0
Prior year service cost (credit) arising during the year	0	0
Net actuarial loss (gain)	0	0
Net amount recognized in accumulated other comprehensive income (loss)	0	0
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss		1
Unrecognized prior service (credit) cost		(2)
Other Post-Retirement Benefit Plans | Duke Energy Ohio
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	1
Current pension liability	2	1
Noncurrent pension liability	17	19
Net amount recognized	(18)
Total accrued pension liability		20
Regulatory assets	0	0
Regulatory liabilities	17	17
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax liability	0	0
Prior year service cost (credit) arising during the year	0	0
Net actuarial loss (gain)	0	0
Net amount recognized in accumulated other comprehensive income (loss)	0	0
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss		0
Unrecognized prior service (credit) cost		(1)
Other Post-Retirement Benefit Plans | Duke Energy Indiana
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	0
Current pension liability	0	0
Noncurrent pension liability	54	59
Net amount recognized	(54)
Total accrued pension liability		59
Regulatory assets	32	36
Regulatory liabilities	62	63
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax liability	0	0
Prior year service cost (credit) arising during the year	0	0
Net actuarial loss (gain)	0	0
Net amount recognized in accumulated other comprehensive income (loss)	0	0
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss		0
Unrecognized prior service (credit) cost		(1)
Other Post-Retirement Benefit Plans | Piedmont
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	7
Current pension liability	0	0
Noncurrent pension liability	0	(4)
Net amount recognized	7
Total accrued pension liability		(4)
Regulatory assets	0	0
Regulatory liabilities	3	3
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax liability	0	0
Prior year service cost (credit) arising during the year	0	0
Net actuarial loss (gain)	0	0
Net amount recognized in accumulated other comprehensive income (loss)	$ 0	0
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss		0
Unrecognized prior service (credit) cost		$ (2)

Employee Benefit Plans (Informa

Employee Benefit Plans (Information For Plans with Accumulated Benefit Obligation in Excess of Plan Assets) (Details) - Pension Plan - Qualified Plan - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Information For Plans With Accumulated Benefit Obligation In Excess Of Plan Assets [Abstract]
Projected benefit obligation	$ 4,914
Accumulated benefit obligation	4,856
Fair value of plan assets	4,837
Progress Energy
Information For Plans With Accumulated Benefit Obligation In Excess Of Plan Assets [Abstract]
Projected benefit obligation	828
Accumulated benefit obligation	796
Fair value of plan assets	783
Duke Energy Florida
Information For Plans With Accumulated Benefit Obligation In Excess Of Plan Assets [Abstract]
Projected benefit obligation	828
Accumulated benefit obligation	796
Fair value of plan assets	783
Duke Energy Ohio
Information For Plans With Accumulated Benefit Obligation In Excess Of Plan Assets [Abstract]
Projected benefit obligation	184	$ 155
Accumulated benefit obligation	176	146
Fair value of plan assets	96	79
Duke Energy Indiana
Information For Plans With Accumulated Benefit Obligation In Excess Of Plan Assets [Abstract]
Projected benefit obligation	293	260
Accumulated benefit obligation	285	252
Fair value of plan assets	$ 183	$ 177

Employee Benefit Plans (Assumpt

Employee Benefit Plans (Assumptions Used For Pension Benefits Accounting) (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pension Plan | Qualified Plan
Benefit Obligations [Abstract]
Discount rate	2.60%	3.30%	4.30%
Interest crediting rate	4.00%	4.00%	4.00%
Net Periodic Benefit Cost [Abstract]
Discount rate	3.30%	4.30%	3.60%
Expected long-term rate of return on plan assets	6.85%	6.85%	6.50%
Pension Plan | Minimum | Qualified Plan
Benefit Obligations [Abstract]
Salary increase	3.50%	3.50%	3.50%
Net Periodic Benefit Cost [Abstract]
Salary increase	3.50%	3.50%	3.50%
Expected long-term rate of return on plan assets
Pension Plan | Maximum | Qualified Plan
Benefit Obligations [Abstract]
Salary increase	4.00%	4.00%	4.00%
Net Periodic Benefit Cost [Abstract]
Salary increase	4.00%	4.00%	4.00%
Other Post-Retirement Benefit Plans
Benefit Obligations [Abstract]
Discount rate	2.60%	3.30%	4.30%
Net Periodic Benefit Cost [Abstract]
Discount rate	3.30%	4.30%	3.60%
Expected long-term rate of return on plan assets	6.85%	6.85%	6.50%
Assumed tax rate	23.00%	23.00%	35.00%

Employee Benefit Plans (Assumed

Employee Benefit Plans (Assumed Health Care Cost Trend Rates) (Details)	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Health care cost trend rate assumed for next year	6.25%	6.00%
Rate to which the cost trend is assumed to decline (the ultimate trend rate)	4.75%	4.75%

Employee Benefit Plans (Expecte

Employee Benefit Plans (Expected Benefit Payments) (Details) $ in Millions	Dec. 31, 2020USD ($)
Pension Plan | Qualified Plan
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	$ 667
2022	650
2023	655
2024	644
2025	617
2026-2030	2,745
Pension Plan | Duke Energy Carolinas | Qualified Plan
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	169
2022	170
2023	174
2024	168
2025	163
2026-2030	677
Pension Plan | Progress Energy | Qualified Plan
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	177
2022	176
2023	181
2024	184
2025	181
2026-2030	846
Pension Plan | Duke Energy Progress | Qualified Plan
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	94
2022	92
2023	95
2024	96
2025	93
2026-2030	399
Pension Plan | Duke Energy Florida | Qualified Plan
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	82
2022	83
2023	85
2024	87
2025	88
2026-2030	443
Pension Plan | Duke Energy Ohio | Qualified Plan
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	40
2022	39
2023	38
2024	37
2025	35
2026-2030	154
Pension Plan | Duke Energy Indiana | Qualified Plan
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	53
2022	51
2023	49
2024	49
2025	47
2026-2030	217
Pension Plan | Piedmont | Qualified Plan
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	29
2022	25
2023	22
2024	21
2025	19
2026-2030	83
Other Post-Retirement Benefit Plans
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	73
2022	66
2023	62
2024	58
2025	54
2026-2030	223
Other Post-Retirement Benefit Plans | Duke Energy Carolinas
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	17
2022	16
2023	15
2024	14
2025	13
2026-2030	54
Other Post-Retirement Benefit Plans | Progress Energy
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	28
2022	26
2023	25
2024	24
2025	22
2026-2030	94
Other Post-Retirement Benefit Plans | Duke Energy Progress
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	15
2022	14
2023	14
2024	13
2025	12
2026-2030	52
Other Post-Retirement Benefit Plans | Duke Energy Florida
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	12
2022	12
2023	11
2024	11
2025	10
2026-2030	41
Other Post-Retirement Benefit Plans | Duke Energy Ohio
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	3
2022	3
2023	3
2024	2
2025	2
2026-2030	9
Other Post-Retirement Benefit Plans | Duke Energy Indiana
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	8
2022	7
2023	6
2024	6
2025	5
2026-2030	21
Other Post-Retirement Benefit Plans | Piedmont
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	2
2022	2
2023	2
2024	2
2025	2
2026-2030	$ 11

Employee Benefit Plans (Target

Employee Benefit Plans (Target and Actual Asset Allocations) (Details)	Dec. 31, 2020	Dec. 31, 2019
Master Trust
Defined Benefit Plan Disclosure [Line Items]
Target allocation	100.00%
Actual asset allocation	100.00%	100.00%
Master Trust | Global equity securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation	28.00%
Actual asset allocation	30.00%	27.00%
Master Trust | Global private equity securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation	1.00%
Actual asset allocation	1.00%	1.00%
Master Trust | Debt securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation	58.00%
Actual asset allocation	55.00%	57.00%
Master Trust | Return seeking debt securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation	4.00%
Actual asset allocation	5.00%	5.00%
Master Trust | Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Target allocation	3.00%
Actual asset allocation	3.00%	3.00%
Master Trust | Real estate and cash
Defined Benefit Plan Disclosure [Line Items]
Target allocation	6.00%
Actual asset allocation	6.00%	7.00%
OPEB
Defined Benefit Plan Disclosure [Line Items]
Target allocation	100.00%
Actual asset allocation	100.00%	100.00%
OPEB | U.S. equity securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation	30.00%
Actual asset allocation	36.00%	35.00%
OPEB | Non-U.S. equity securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation	6.00%
Actual asset allocation	6.00%	9.00%
OPEB | Debt securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation	45.00%
Actual asset allocation	42.00%	37.00%
OPEB | Real estate
Defined Benefit Plan Disclosure [Line Items]
Target allocation	2.00%
Actual asset allocation	2.00%	2.00%
OPEB | Cash
Defined Benefit Plan Disclosure [Line Items]
Target allocation	17.00%
Actual asset allocation	14.00%	17.00%

Employee Benefit Plans (Fair Va

Employee Benefit Plans (Fair Value Measurements of Plan Assets - Master Retirement Trust) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Level 3
Defined Benefit Plan Disclosure [Line Items]
Total assets	$ 0	$ 11	$ 27
Master Trust
Defined Benefit Plan Disclosure [Line Items]
Total assets	9,479	9,025
Master Trust | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total assets	3,541	3,199
Master Trust | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total assets	5,603	5,487
Master Trust | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	11
Master Trust | Not Categorized
Defined Benefit Plan Disclosure [Line Items]
Total assets	335	328
Master Trust | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Total assets	3,202	2,730
Master Trust | Equity securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total assets	3,162	2,712
Master Trust | Equity securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Equity securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Equity securities | Not Categorized
Defined Benefit Plan Disclosure [Line Items]
Total assets	40	18
Master Trust | Corporate debt securities
Defined Benefit Plan Disclosure [Line Items]
Total assets	4,162	3,999
Master Trust | Corporate debt securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Corporate debt securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total assets	4,162	3,999
Master Trust | Corporate debt securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Corporate debt securities | Not Categorized
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Short-term investment funds
Defined Benefit Plan Disclosure [Line Items]
Total assets	397	545
Master Trust | Short-term investment funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total assets	247	455
Master Trust | Short-term investment funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total assets	150	90
Master Trust | Short-term investment funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Short-term investment funds | Not Categorized
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Partnership interests
Defined Benefit Plan Disclosure [Line Items]
Total assets	97	104
Master Trust | Partnership interests | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Partnership interests | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Partnership interests | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Partnership interests | Not Categorized
Defined Benefit Plan Disclosure [Line Items]
Total assets	97	104
Master Trust | Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Total assets	198	206
Master Trust | Hedge funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Hedge funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Hedge funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Hedge funds | Not Categorized
Defined Benefit Plan Disclosure [Line Items]
Total assets	198	206
Master Trust | U.S. government bonds
Defined Benefit Plan Disclosure [Line Items]
Total assets	1,164	1,231
Master Trust | U.S. government bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | U.S. government bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total assets	1,164	1,231
Master Trust | U.S. government bonds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | U.S. government bonds | Not Categorized
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Guaranteed investment contracts
Defined Benefit Plan Disclosure [Line Items]
Total assets		11
Master Trust | Guaranteed investment contracts | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total assets		0
Master Trust | Guaranteed investment contracts | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total assets		0
Master Trust | Guaranteed investment contracts | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total assets		11
Master Trust | Guaranteed investment contracts | Not Categorized
Defined Benefit Plan Disclosure [Line Items]
Total assets		0
Master Trust | Governments bonds – foreign
Defined Benefit Plan Disclosure [Line Items]
Total assets	73	78
Master Trust | Governments bonds – foreign | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Governments bonds – foreign | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total assets	73	78
Master Trust | Governments bonds – foreign | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Governments bonds – foreign | Not Categorized
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Cash
Defined Benefit Plan Disclosure [Line Items]
Total assets	98	75
Master Trust | Cash | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total assets	98	75
Master Trust | Cash | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Cash | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Cash | Not Categorized
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Net pending transactions and other investments
Defined Benefit Plan Disclosure [Line Items]
Total assets	88	46
Master Trust | Net pending transactions and other investments | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total assets	34	(43)
Master Trust | Net pending transactions and other investments | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total assets	54	89
Master Trust | Net pending transactions and other investments | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
Master Trust | Net pending transactions and other investments | Not Categorized
Defined Benefit Plan Disclosure [Line Items]
Total assets	0	0
OPEB
Defined Benefit Plan Disclosure [Line Items]
Total assets	48	50
OPEB | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total assets	48	50
OPEB | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Total assets	23	22
OPEB | Equity securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total assets	23	22
OPEB | Real estate
Defined Benefit Plan Disclosure [Line Items]
Total assets	1	1
OPEB | Real estate | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total assets	1	1
OPEB | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Total assets	5	9
OPEB | Cash and cash equivalents | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total assets	5	9
OPEB | Debt securities
Defined Benefit Plan Disclosure [Line Items]
Total assets	19	18
OPEB | Debt securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total assets	$ 19	$ 18
Duke Energy Carolinas | Master Trust
Defined Benefit Plan Disclosure [Line Items]
Allocated assets	26.00%	26.00%
Progress Energy | Master Trust
Defined Benefit Plan Disclosure [Line Items]
Allocated assets	32.00%	31.00%
Duke Energy Progress | Master Trust
Defined Benefit Plan Disclosure [Line Items]
Allocated assets	15.00%	15.00%
Duke Energy Florida | Master Trust
Defined Benefit Plan Disclosure [Line Items]
Allocated assets	17.00%	17.00%
Duke Energy Ohio | Master Trust
Defined Benefit Plan Disclosure [Line Items]
Allocated assets	5.00%	5.00%
Duke Energy Indiana | Master Trust
Defined Benefit Plan Disclosure [Line Items]
Allocated assets	7.00%	7.00%
Piedmont | Master Trust
Defined Benefit Plan Disclosure [Line Items]
Allocated assets	4.00%	4.00%

Employee Benefit Plans (Reconci

Employee Benefit Plans (Reconciliation of Assets Measured at Fair Value on a Recurring Basis) (Details) - Level 3 - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Plan assets at prior measurement date	$ 11	$ 27
Sales	(12)	(18)
Total gains and other, net	1	2
Transfer of Level 3 assets to other classifications	0	0
Plan assets at measurement date	$ 0	$ 11

Employee Benefit Plans (Employe

Employee Benefit Plans (Employee Savings Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Matching contribution percentage	100.00%
Eligible pay percentage	6.00%
Additional contribution percentage for employees not participating in defined pension plans	4.00%
Employer contributions	$ 213	$ 214	$ 213
Vesting period	3 years
Duke Energy Carolinas
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 67	66	68
Progress Energy
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	57	58	58
Duke Energy Progress
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	38	38	40
Duke Energy Florida
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	19	20	19
Duke Energy Ohio
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	5	5	4
Duke Energy Indiana
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	11	11	10
Piedmont
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 13	$ 13	$ 12
Minimum | Piedmont
Defined Benefit Plan Disclosure [Line Items]
Additional contribution percentage for employees not participating in defined pension plans	3.00%
Maximum | Piedmont
Defined Benefit Plan Disclosure [Line Items]
Additional contribution percentage for employees not participating in defined pension plans	5.00%

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Sep. 30, 2020	Dec. 31, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Line Items]
Refund of AMT credit carryforwards			$ 572	$ 573
Deferred tax liabilities			$ 117
Reclassification of AMT credits from noncurrent deferred tax liabilities to a current federal income tax receivable				286
AMT credit carryforwards
Income Tax Disclosure [Line Items]
Refund of AMT credit carryforwards	$ 572			$ 573
Income tax interest income	$ 19
Analysis of existing regulatory liability
Income Tax Disclosure [Line Items]
Measurement period adjustment					$ 23
Bonus depreciation
Income Tax Disclosure [Line Items]
Measurement period adjustment					10
Nondeductible long-term incentives
Income Tax Disclosure [Line Items]
Measurement period adjustment					7
Refundable AMT credits
Income Tax Disclosure [Line Items]
Measurement period adjustment		$ 76
Regulatory liability
Income Tax Disclosure [Line Items]
Measurement period adjustment					83
Reclassified AMT credit carryforwards
Income Tax Disclosure [Line Items]
Measurement period adjustment					$ 573

Income Taxes (Components of Inc

Income Taxes (Components of Income Tax Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current income taxes
Federal	$ (281)	$ (299)	$ (647)
State	(9)	10	(11)
Foreign	1	2	3
Total current income taxes	(289)	(287)	(655)
Deferred income taxes
Federal	155	855	1,064
State	(92)	(38)	49
Total deferred income taxes	63	817	1,113
ITC amortization	(10)	(11)	(10)
Income tax (benefit) expense from continuing operations	(236)	519	448
Tax expense from discontinued operations	2	(2)	(26)
Total income tax (benefit) expense included in Consolidated Statements of Operations	(234)	517	422
Net operating loss carry forward	79	775	(18)
Duke Energy Income from Continuing Operations Before Income Taxes [Abstract]
Domestic	826	4,053	3,018
Foreign	13	44	55
Total income from continuing operations before income taxes	839	4,097	3,073
Duke Energy Carolinas
Current income taxes
Federal	314	164	(8)
State	35	13	6
Foreign		0	0
Total current income taxes	349	177	(2)
Deferred income taxes
Federal	(171)	175	299
State	(86)	(37)	11
Total deferred income taxes	(257)	138	310
ITC amortization	(4)	(4)	(5)
Income tax (benefit) expense from continuing operations	88	311	303
Total income tax (benefit) expense included in Consolidated Statements of Operations	88	311	303
Net operating loss carry forward	20	8	(22)
Duke Energy Income from Continuing Operations Before Income Taxes [Abstract]
Total income from continuing operations before income taxes	1,044	1,714	1,374
Progress Energy
Current income taxes
Federal	280	(173)	(135)
State	29	(7)	(5)
Foreign		0	0
Total current income taxes	309	(180)	(140)
Deferred income taxes
Federal	(167)	422	341
State	(24)	17	20
Total deferred income taxes	(191)	439	361
ITC amortization	(5)	(6)	(3)
Income tax (benefit) expense from continuing operations	113	253	218
Total income tax (benefit) expense included in Consolidated Statements of Operations	113	253	218
Net operating loss carry forward	39	243	(293)
Duke Energy Progress
Current income taxes
Federal	181	(36)	(71)
State	17	(3)	(5)
Foreign		0	0
Total current income taxes	198	(39)	(76)
Deferred income taxes
Federal	(180)	220	256
State	(49)	(18)	(17)
Total deferred income taxes	(229)	202	239
ITC amortization	(5)	(6)	(3)
Income tax (benefit) expense from continuing operations	(36)	157	160
Total income tax (benefit) expense included in Consolidated Statements of Operations	(36)	157	160
Net operating loss carry forward	3	35	(59)
Duke Energy Income from Continuing Operations Before Income Taxes [Abstract]
Total income from continuing operations before income taxes	379	962	827
Duke Energy Florida
Current income taxes
Federal	148	(43)	(49)
State	24	18	(10)
Foreign		0	0
Total current income taxes	172	(25)	(59)
Deferred income taxes
Federal	1	153	115
State	25	27	45
Total deferred income taxes	26	180	160
ITC amortization		0	0
Income tax (benefit) expense from continuing operations	198	155	101
Total income tax (benefit) expense included in Consolidated Statements of Operations	198	155	101
Net operating loss carry forward	30	152	(219)
Duke Energy Income from Continuing Operations Before Income Taxes [Abstract]
Total income from continuing operations before income taxes	969	847	655
Duke Energy Ohio
Current income taxes
Federal	10	(41)	20
State	1	(1)	(1)
Foreign		0	0
Total current income taxes	11	(42)	19
Deferred income taxes
Federal	30	77	21
State	2	5	3
Total deferred income taxes	32	82	24
ITC amortization		0	0
Income tax (benefit) expense from continuing operations	43	40	43
Total income tax (benefit) expense included in Consolidated Statements of Operations	43	40	43
Net operating loss carry forward		25	(17)
Duke Energy Income from Continuing Operations Before Income Taxes [Abstract]
Total income from continuing operations before income taxes	295	279	219
Duke Energy Indiana
Current income taxes
Federal	48	(23)	29
State	7	1	3
Foreign		0	0
Total current income taxes	55	(22)	32
Deferred income taxes
Federal	12	128	74
State	17	28	22
Total deferred income taxes	29	156	96
ITC amortization		0	0
Income tax (benefit) expense from continuing operations	84	134	128
Total income tax (benefit) expense included in Consolidated Statements of Operations	84	134	128
Net operating loss carry forward	8	60	(21)
Duke Energy Income from Continuing Operations Before Income Taxes [Abstract]
Total income from continuing operations before income taxes	492	570	521
Piedmont
Current income taxes
Federal	(27)	(92)	67
State	(8)	(1)	1
Foreign		0	0
Total current income taxes	(35)	(93)	68
Deferred income taxes
Federal	60	133	(36)
State	(7)	3	5
Total deferred income taxes	53	136	(31)
ITC amortization		0	0
Income tax (benefit) expense from continuing operations	18	43	37
Total income tax (benefit) expense included in Consolidated Statements of Operations	18	43	37
Net operating loss carry forward	11	90	(39)
Duke Energy Income from Continuing Operations Before Income Taxes [Abstract]
Total income from continuing operations before income taxes	$ 291	$ 245	$ 166

Income Taxes (Effective Tax Rat

Income Taxes (Effective Tax Rates) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract]
Income tax expense, computed at the statutory rate of 21%	$ 176	$ 860	$ 645
State income tax, net of federal income tax effect	(80)	(22)	30
Amortization of excess deferred income tax	(276)	(121)	(61)
AFUDC equity income	(48)	(52)	(42)
AFUDC equity depreciation	103	34	31
Noncontrolling Interests	62
Renewable energy PTCs	(110)	(120)	(129)
Other tax credits	(37)	(23)	(28)
Tax Act			20
Tax true up	(12)	(64)
Other items, net	(14)	27	(18)
Income tax (benefit) expense from continuing operations	$ (236)	$ 519	$ 448
Effective tax rate	(28.10%)	12.70%	14.60%
Duke Energy Carolinas
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract]
Income tax expense, computed at the statutory rate of 21%	$ 219	$ 360	$ 288
State income tax, net of federal income tax effect	(40)	(19)	14
Amortization of excess deferred income tax	(82)	(29)
AFUDC equity income	(13)	(9)	(15)
AFUDC equity depreciation	19	19	18
Other tax credits	(13)	(11)	(7)
Tax Act			1
Tax true up	(3)	(9)
Other items, net	1	9	4
Income tax (benefit) expense from continuing operations	$ 88	$ 311	$ 303
Effective tax rate	8.40%	18.10%	22.10%
Progress Energy
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract]
Income tax expense, computed at the statutory rate of 21%	$ 243	$ 332	$ 263
State income tax, net of federal income tax effect	4	8	13
Amortization of excess deferred income tax	(118)	(64)	(55)
AFUDC equity income	(9)	(14)	(22)
AFUDC equity depreciation	10	10	9
Other tax credits	(16)	(9)	(13)
Tax Act			25
Tax true up	1	(8)
Other items, net	(2)	(2)	(2)
Income tax (benefit) expense from continuing operations	$ 113	$ 253	$ 218
Effective tax rate	9.70%	16.00%	17.40%
Duke Energy Progress
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract]
Income tax expense, computed at the statutory rate of 21%	$ 80	$ 202	$ 174
State income tax, net of federal income tax effect	(25)	(17)	(17)
Amortization of excess deferred income tax	(68)	(10)	(1)
AFUDC equity income	(6)	(13)	(12)
AFUDC equity depreciation	5	5	5
Other tax credits	(14)	(7)	(5)
Tax Act			19
Tax true up	(5)	(3)
Other items, net	(3)	0	(3)
Income tax (benefit) expense from continuing operations	$ (36)	$ 157	$ 160
Effective tax rate	(9.50%)	16.30%	19.30%
Duke Energy Florida
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract]
Income tax expense, computed at the statutory rate of 21%	$ 204	$ 178	$ 137
State income tax, net of federal income tax effect	39	35	28
Amortization of excess deferred income tax	(49)	(54)	(54)
AFUDC equity income	(3)	(1)	(10)
AFUDC equity depreciation	5	5	4
Other tax credits	(2)	(2)	(8)
Tax Act			0
Tax true up	5	(5)
Other items, net	(1)	(1)	4
Income tax (benefit) expense from continuing operations	$ 198	$ 155	$ 101
Effective tax rate	20.40%	18.30%	15.40%
Duke Energy Ohio
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract]
Income tax expense, computed at the statutory rate of 21%	$ 62	$ 59	$ 46
State income tax, net of federal income tax effect	2	3	2
Amortization of excess deferred income tax	(20)	(12)	(3)
AFUDC equity income	(2)	(3)	(2)
AFUDC equity depreciation	1	1	1
Other tax credits	(1)	(1)	(1)
Tax Act			2
Tax true up	0	(7)
Other items, net	1	0	(2)
Income tax (benefit) expense from continuing operations	$ 43	$ 40	$ 43
Effective tax rate	14.60%	14.30%	19.60%
Duke Energy Indiana
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract]
Income tax expense, computed at the statutory rate of 21%	$ 103	$ 120	$ 109
State income tax, net of federal income tax effect	19	22	20
Amortization of excess deferred income tax	(36)	(6)	(2)
AFUDC equity income	(4)	(3)	(2)
AFUDC equity depreciation	4	4	4
Noncontrolling Interests	0
Other tax credits	(3)	(1)	(1)
Tax true up	(1)	(1)
Other items, net	2	(1)
Income tax (benefit) expense from continuing operations	$ 84	$ 134	$ 128
Effective tax rate	17.10%	23.50%	24.60%
Piedmont
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract]
Income tax expense, computed at the statutory rate of 21%	$ 61	$ 51	$ 35
State income tax, net of federal income tax effect	(12)	2	4
Amortization of excess deferred income tax	(21)	(10)
AFUDC equity income	(10)
Other tax credits	(2)	(1)	(3)
Tax true up	1	0
Other items, net	1	1	1
Income tax (benefit) expense from continuing operations	$ 18	$ 43	$ 37
Effective tax rate	6.20%	17.60%	22.30%

Income Taxes (Deferred Income T

Income Taxes (Deferred Income Taxes) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Deferred Tax Assets, Gross [Abstract]
Deferred credits and other liabilities	$ 286	$ 125
Lease obligations	515	462
Pension, post-retirement and other employee benefits	236	303
Progress Energy merger purchase accounting adjustments	441	389
Tax credits and NOL carryforwards	3,909	3,925
Other	93	97
Valuation allowance	(586)	(587)
Total deferred income tax assets	4,894	4,714
Deferred Tax Liabilities, Gross [Abstract]
Investments and other assets	(2,267)	(1,664)
Accelerated depreciation rates	(10,729)	(10,813)
Regulatory assets and deferred debits, net	(1,142)	(1,115)
Total deferred income tax liabilities	(14,138)	(13,592)
Net deferred income tax liabilities	(9,244)	(8,878)
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract]
Tax credits and NOL carryforwards	3,909	3,925
Valuation allowance	586	587
General Business Credits
Deferred Tax Assets, Gross [Abstract]
Tax credits and NOL carryforwards	2,033
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract]
Tax credits and NOL carryforwards	2,033
NOL Carryforwards | Federal
Deferred Tax Assets, Gross [Abstract]
Tax credits and NOL carryforwards	154
Valuation allowance	(4)
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract]
Tax credits and NOL carryforwards	154
Valuation allowance	4
NOL Carryforwards | State
Deferred Tax Assets, Gross [Abstract]
Tax credits and NOL carryforwards	340
Valuation allowance	(97)
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract]
Tax credits and NOL carryforwards	340
Valuation allowance	97
NOL Carryforwards | Foreign
Deferred Tax Assets, Gross [Abstract]
Tax credits and NOL carryforwards	12
Valuation allowance	(12)
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract]
Tax credits and NOL carryforwards	12
Valuation allowance	12
Capital loss carryforwards | Federal
Deferred Tax Assets, Gross [Abstract]
Tax credits and NOL carryforwards	85
Valuation allowance	(85)
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract]
Tax credits and NOL carryforwards	85
Valuation allowance	85
Foreign Tax Credit
Deferred Tax Assets, Gross [Abstract]
Valuation allowance	(388)
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract]
Valuation allowance	388
Foreign Tax Credit | Foreign
Deferred Tax Assets, Gross [Abstract]
Tax credits and NOL carryforwards	1,272
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract]
Tax credits and NOL carryforwards	1,272
Charitable contribution carryforwards
Deferred Tax Assets, Gross [Abstract]
Tax credits and NOL carryforwards	13
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract]
Tax credits and NOL carryforwards	13
Duke Energy Carolinas
Deferred Tax Assets, Gross [Abstract]
Deferred credits and other liabilities	85	24
Lease obligations	96	72
Pension, post-retirement and other employee benefits	(30)	(5)
Tax credits and NOL carryforwards	285	262
Regulatory liabilities and deferred credits	11
Other	8	5
Total deferred income tax assets	455	358
Deferred Tax Liabilities, Gross [Abstract]
Investments and other assets	(1,127)	(981)
Accelerated depreciation rates	(3,170)	(3,254)
Regulatory assets and deferred debits, net		(44)
Total deferred income tax liabilities	(4,297)	(4,279)
Net deferred income tax liabilities	(3,842)	(3,921)
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract]
Tax credits and NOL carryforwards	285	262
Progress Energy
Deferred Tax Assets, Gross [Abstract]
Deferred credits and other liabilities	87	25
Lease obligations	208	193
Pension, post-retirement and other employee benefits	68	88
Tax credits and NOL carryforwards	508	486
Other	14	8
Total deferred income tax assets	885	800
Deferred Tax Liabilities, Gross [Abstract]
Investments and other assets	(669)	(577)
Accelerated depreciation rates	(3,868)	(3,798)
Regulatory assets and deferred debits, net	(744)	(887)
Total deferred income tax liabilities	(5,281)	(5,262)
Net deferred income tax liabilities	(4,396)	(4,462)
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract]
Tax credits and NOL carryforwards	508	486
Duke Energy Progress
Deferred Tax Assets, Gross [Abstract]
Deferred credits and other liabilities	67	49
Lease obligations	120	92
Pension, post-retirement and other employee benefits	24	38
Tax credits and NOL carryforwards	179	176
Other	9	3
Total deferred income tax assets	399	358
Deferred Tax Liabilities, Gross [Abstract]
Investments and other assets	(507)	(390)
Accelerated depreciation rates	(1,778)	(1,918)
Regulatory assets and deferred debits, net	(412)	(438)
Total deferred income tax liabilities	(2,697)	(2,746)
Net deferred income tax liabilities	(2,298)	(2,388)
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract]
Tax credits and NOL carryforwards	179	176
Duke Energy Florida
Deferred Tax Assets, Gross [Abstract]
Deferred credits and other liabilities	18
Lease obligations	87	102
Pension, post-retirement and other employee benefits	38	44
Tax credits and NOL carryforwards	282	253
Other	4	2
Total deferred income tax assets	429	401
Deferred Tax Liabilities, Gross [Abstract]
Investments and other assets	(164)	(190)
Accelerated depreciation rates	(2,124)	(1,913)
Regulatory assets and deferred debits, net	(332)	(477)
Total deferred income tax liabilities	(2,620)	(2,580)
Net deferred income tax liabilities	(2,191)	(2,179)
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract]
Tax credits and NOL carryforwards	282	253
Duke Energy Ohio
Deferred Tax Assets, Gross [Abstract]
Deferred credits and other liabilities	21	14
Lease obligations	5	5
Pension, post-retirement and other employee benefits	16	17
Tax credits and NOL carryforwards	16	16
Regulatory liabilities and deferred credits	18	36
Investments and other assets	7	10
Other	7	8
Total deferred income tax assets	90	106
Deferred Tax Liabilities, Gross [Abstract]
Accelerated depreciation rates	(1,071)	(1,028)
Total deferred income tax liabilities	(1,071)	(1,028)
Net deferred income tax liabilities	(981)	(922)
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract]
Tax credits and NOL carryforwards	16	16
Duke Energy Indiana
Deferred Tax Assets, Gross [Abstract]
Deferred credits and other liabilities	7	5
Lease obligations	16	17
Pension, post-retirement and other employee benefits	26	27
Tax credits and NOL carryforwards	183	176
Regulatory liabilities and deferred credits	0	52
Investments and other assets
Other	1	1
Total deferred income tax assets	233	278
Deferred Tax Liabilities, Gross [Abstract]
Investments and other assets	(14)	(12)
Accelerated depreciation rates	(1,433)	(1,416)
Regulatory assets and deferred debits, net	(14)
Total deferred income tax liabilities	(1,461)	(1,428)
Net deferred income tax liabilities	(1,228)	(1,150)
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract]
Tax credits and NOL carryforwards	183	176
Piedmont
Deferred Tax Assets, Gross [Abstract]
Deferred credits and other liabilities	38	22
Lease obligations	5	6
Pension, post-retirement and other employee benefits	(5)	(3)
Tax credits and NOL carryforwards	29	19
Regulatory liabilities and deferred credits		42
Investments and other assets		2
Other	8	6
Total deferred income tax assets	75	94
Deferred Tax Liabilities, Gross [Abstract]
Investments and other assets	(48)
Accelerated depreciation rates	(844)	(802)
Regulatory assets and deferred debits, net	(4)
Total deferred income tax liabilities	(896)	(802)
Net deferred income tax liabilities	(821)	(708)
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract]
Tax credits and NOL carryforwards	$ 29	$ 19

Income Taxes (Other Disclosures

Income Taxes (Other Disclosures) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits – January 1	$ 126	$ 24	$ 25
Gross decreases – tax positions in prior periods	(2)	(3)	(2)
Gross increases – current period tax positions	4	105
Gross increases – tax positions in prior periods			7
Decreases due to settlements			(6)
Reduction due to lapse of statute of limitations	(3)
Total changes	(1)	102	(1)
Unrecognized tax benefits – December 31	125	126	24
Amount that if recognized, would affect the effective tax rate or regulatory liability	122
Duke Energy Carolinas
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits – January 1	8	6	5
Gross decreases – tax positions in prior periods			(1)
Gross increases – current period tax positions	2	2
Gross increases – tax positions in prior periods			2
Total changes	2	2	1
Unrecognized tax benefits – December 31	10	8	6
Amount that if recognized, would affect the effective tax rate or regulatory liability	10
Progress Energy
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits – January 1	9	9	5
Gross decreases – tax positions in prior periods		(1)
Gross increases – current period tax positions	1	1
Gross increases – tax positions in prior periods			4
Total changes	1	0	4
Unrecognized tax benefits – December 31	10	9	9
Amount that if recognized, would affect the effective tax rate or regulatory liability	10
Duke Energy Progress
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits – January 1	6	6	5
Gross decreases – tax positions in prior periods		(1)
Gross increases – current period tax positions	0	1
Gross increases – tax positions in prior periods			1
Total changes		0	1
Unrecognized tax benefits – December 31	6	6	6
Amount that if recognized, would affect the effective tax rate or regulatory liability	6
Duke Energy Florida
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits – January 1	3	3	5
Gross decreases – tax positions in prior periods			(4)
Gross increases – current period tax positions	0
Gross increases – tax positions in prior periods			2
Total changes		0	(2)
Unrecognized tax benefits – December 31	3	3	3
Amount that if recognized, would affect the effective tax rate or regulatory liability	3
Duke Energy Ohio
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits – January 1	1	1	1
Gross increases – current period tax positions	0
Total changes			0
Unrecognized tax benefits – December 31	1	1	1
Amount that if recognized, would affect the effective tax rate or regulatory liability	1
Duke Energy Indiana
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits – January 1	1	1	1
Total changes			0
Unrecognized tax benefits – December 31	1	1	1
Amount that if recognized, would affect the effective tax rate or regulatory liability	1
Piedmont
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits – January 1	4	4	3
Gross increases – tax positions in prior periods			1
Reduction due to lapse of statute of limitations	(3)
Total changes	(3)		1
Unrecognized tax benefits – December 31	1	$ 4	$ 4
Amount that if recognized, would affect the effective tax rate or regulatory liability	$ 1

Other Income and Expenses, Ne_2

Other Income and Expenses, Net (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Component Of Other Income Expense Nonoperating [Line Items]
Interest income	$ 32	$ 31	$ 20
AFUDC equity	154	139	221
Post in-service equity returns	27	29	15
Nonoperating income, other	240	231	143
Other income and expense, net	453	430	399
Duke Energy Carolinas
Component Of Other Income Expense Nonoperating [Line Items]
Interest income	4	1	1
AFUDC equity	62	42	73
Post in-service equity returns	17	20	9
Nonoperating income, other	94	88	70
Other income and expense, net	177	151	153
Progress Energy
Component Of Other Income Expense Nonoperating [Line Items]
Interest income	8	11	18
AFUDC equity	42	66	104
Post in-service equity returns	8	7	5
Nonoperating income, other	71	57	38
Other income and expense, net	129	141	165
Duke Energy Progress
Component Of Other Income Expense Nonoperating [Line Items]
Interest income	2	0	1
AFUDC equity	29	60	57
Post in-service equity returns	8	7	5
Nonoperating income, other	36	33	24
Other income and expense, net	75	100	87
Duke Energy Florida
Component Of Other Income Expense Nonoperating [Line Items]
Interest income	6	11	18
AFUDC equity	12	6	47
Nonoperating income, other	35	31	21
Other income and expense, net	53	48	86
Duke Energy Ohio
Component Of Other Income Expense Nonoperating [Line Items]
Interest income	4	10	7
AFUDC equity	7	13	11
Post in-service equity returns	1	1	1
Nonoperating income, other	4	0	4
Other income and expense, net	16	24	23
Duke Energy Indiana
Component Of Other Income Expense Nonoperating [Line Items]
Interest income	6	10	9
AFUDC equity	23	18	32
Post in-service equity returns	1
Nonoperating income, other	7	13	4
Other income and expense, net	37	41	45
Piedmont
Component Of Other Income Expense Nonoperating [Line Items]
Interest income	17	1	1
AFUDC equity	19
Nonoperating income, other	15	19	13
Other income and expense, net	$ 51	$ 20	$ 14

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Event - Commercial Renewables $ in Millions	1 Months Ended
	Feb. 25, 2021USD ($)
Maximum
Subsequent Event [Line Items]
Winter storm impact in Texas	$ 100
Minimum
Subsequent Event [Line Items]
Winter storm impact in Texas	$ 75