Progress Energy (PREX) 10-Q 4 Nov 21 2021 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 30, 2021	Oct. 31, 2021
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
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	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 Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		769,343,372
Entity Central Index Key	0001326160
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false
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 Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0000030371
Current Fiscal Year End Date	--12-31
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 Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0001094093
Current Fiscal Year End Date	--12-31
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 Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0000017797
Current Fiscal Year End Date	--12-31
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 Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0000037637
Current Fiscal Year End Date	--12-31
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 Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0000020290
Current Fiscal Year End Date	--12-31
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 Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0000081020
Current Fiscal Year End Date	--12-31
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 Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0000078460
Current Fiscal Year End Date	--12-31
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 5.625% 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

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Millions, $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Operating Revenues
Regulated electric		$ 6,495	$ 6,315	$ 16,972	$ 16,402
Regulated natural gas		263	214	1,314	1,115
Nonregulated electric and other		193	192	573	574
Total operating revenues		6,951	6,721	18,859	18,091
Operating Expenses
Operation, maintenance and other		1,507	1,450	4,319	4,142
Depreciation and amortization		1,265	1,217	3,698	3,497
Property and other taxes		371	324	1,073	1,003
Impairment of assets and other charges		211	28	342	36
Total operating expenses		5,273	4,909	14,564	13,622
(Losses) Gains on Sales of Other Assets and Other, net		9	2	11	10
Operating Income		1,687	1,814	4,306	4,479
Other Income and Expenses
Equity in earnings (losses) of unconsolidated affiliates		22	(80)	14	(2,004)
Other income and expenses, net		238	127	493	310
Total other income and expenses		260	47	507	(1,694)
Interest Expense		581	522	1,688	1,627
Income Before Income Taxes		1,366	1,339	3,125	1,158
Income Tax Expense (Benefit)		90	105	210	(74)
Net Income		1,276	1,234	2,915	1,232
Add: Net Loss Attributable to Noncontrolling Interests		129	70	247	208
Net Income and Comprehensive Income		1,405	1,304	3,162	1,440
Less: Preferred Dividends		39	39	92	93
Net Income Available to Duke Energy Corporation Common Stockholders		1,366	1,265	3,070	1,347
Other Comprehensive Income (Loss), net of tax
Pension and OPEB adjustments	[1]	1	1	3	1
Net unrealized (losses) gains on cash flow hedges	[1]	9	(83)	(59)	(159)
Unrealized (losses) gains on available-for-sale securities	[1]	(2)	(2)	(6)	5
Other Comprehensive Income (Loss), net of tax	[1]	10	(80)	(53)	(145)
Comprehensive Income		1,286	1,154	2,862	1,087
Add: Comprehensive Loss Attributable to Noncontrolling Interests		(128)	(70)	(240)	(220)
Comprehensive Income Attributable to Duke Energy		$ 1,414	$ 1,224	$ 3,102	$ 1,307
Net income (loss) attributable to Duke Energy Corporation common stockholders
Basic (in usd per share)		$ 1.79	$ 1.74	$ 4	$ 1.85
Diluted (in usd per share)		$ 1.79	$ 1.74	$ 4	$ 1.85
Weighted Average Shares Outstanding
Basic (in shares)		769	735	769	735
Diluted (in shares)		769	735	769	735
Duke Energy Carolinas
Operating Revenues
Total operating revenues		$ 2,104	$ 2,058	$ 5,430	$ 5,416
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		452	497	1,218	1,326
Operation, maintenance and other		471	402	1,347	1,218
Depreciation and amortization		366	372	1,088	1,090
Property and other taxes		91	57	248	213
Impairment of assets and other charges		163	20	238	22
Total operating expenses		1,543	1,348	4,139	3,869
(Losses) Gains on Sales of Other Assets and Other, net		(1)	1	1	1
Operating Income		560	711	1,292	1,548
Other Income and Expenses
Total other income and expenses		126	42	218	128
Interest Expense		137	122	400	370
Income Before Income Taxes		549	631	1,110	1,306
Income Tax Expense (Benefit)		16	76	40	178
Net Income and Comprehensive Income		533	555	1,070	1,128
Progress Energy
Operating Revenues
Total operating revenues		3,233	3,197	8,417	8,117
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		1,074	1,088	2,702	2,628
Operation, maintenance and other		636	646	1,863	1,789
Depreciation and amortization		504	472	1,430	1,356
Property and other taxes		144	147	419	419
Impairment of assets and other charges		42	1	79	1
Total operating expenses		2,400	2,354	6,493	6,193
(Losses) Gains on Sales of Other Assets and Other, net		8	3	9	9
Operating Income		841	846	1,933	1,933
Other Income and Expenses
Total other income and expenses		86	24	167	89
Interest Expense		200	194	592	599
Income Before Income Taxes		727	676	1,508	1,423
Income Tax Expense (Benefit)		94	70	174	190
Net Income		633	606	1,334	1,233
Add: Net Loss Attributable to Noncontrolling Interests		(1)	(1)	(1)	(1)
Net Income and Comprehensive Income		632	605	1,333	1,232
Other Comprehensive Income (Loss), net of tax
Pension and OPEB adjustments		(1)			1
Net unrealized (losses) gains on cash flow hedges		1	1	2	3
Unrealized (losses) gains on available-for-sale securities			1		1
Other Comprehensive Income (Loss), net of tax			2	2	5
Comprehensive Income		633	608	1,336	1,238
Add: Comprehensive Loss Attributable to Noncontrolling Interests		1	1	1	1
Comprehensive Income Attributable to Duke Energy		632	607	1,335	1,237
Duke Energy Progress
Operating Revenues
Total operating revenues		1,667	1,626	4,417	4,207
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		523	537	1,368	1,337
Operation, maintenance and other		368	348	1,092	970
Depreciation and amortization		290	289	811	833
Property and other taxes		39	38	129	129
Impairment of assets and other charges		42	5	60	5
Total operating expenses		1,262	1,217	3,460	3,274
(Losses) Gains on Sales of Other Assets and Other, net		7	3	8	8
Operating Income		412	412	965	941
Other Income and Expenses
Total other income and expenses		67	11	111	52
Interest Expense		79	66	226	203
Income Before Income Taxes		400	357	850	790
Income Tax Expense (Benefit)		25	11	50	79
Net Income and Comprehensive Income		375	346	800	711
Duke Energy Florida
Operating Revenues
Total operating revenues		1,561	1,567	3,987	3,897
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		552	551	1,335	1,291
Operation, maintenance and other		263	292	760	806
Depreciation and amortization		214	183	619	523
Property and other taxes		105	110	290	290
Impairment of assets and other charges			(4)	19	(4)
Total operating expenses		1,134	1,132	3,023	2,906
(Losses) Gains on Sales of Other Assets and Other, net		1		1
Operating Income		428	435	965	991
Other Income and Expenses
Total other income and expenses		18	11	54	36
Interest Expense		79	81	239	245
Income Before Income Taxes		367	365	780	782
Income Tax Expense (Benefit)		70	78	149	159
Net Income and Comprehensive Income		297	287	631	623
Other Comprehensive Income (Loss), net of tax
Unrealized (losses) gains on available-for-sale securities			1		1
Other Comprehensive Income (Loss), net of tax			1		1
Comprehensive Income Attributable to Duke Energy		297	288	631	624
Duke Energy Ohio
Operating Revenues
Regulated electric		413	394	1,119	1,070
Regulated natural gas		93	79	375	324
Total operating revenues		506	473	1,494	1,394
Operating Expenses
Operation, maintenance and other		116	115	335	333
Depreciation and amortization		79	72	228	208
Property and other taxes		91	83	266	244
Impairment of assets and other charges				5
Total operating expenses		414	367	1,204	1,089
Operating Income		92	106	290	305
Other Income and Expenses
Total other income and expenses		4	4	14	11
Interest Expense		29	26	82	75
Income Before Income Taxes		67	84	222	241
Income Tax Expense (Benefit)		9	14	34	40
Net Income and Comprehensive Income		58	70	188	201
Duke Energy Indiana
Operating Revenues
Total operating revenues		886	761	2,366	2,070
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		292	222	710	577
Operation, maintenance and other		173	207	543	564
Depreciation and amortization		154	149	458	415
Property and other taxes		16	15	57	57
Impairment of assets and other charges				8
Total operating expenses		635	593	1,776	1,613
(Losses) Gains on Sales of Other Assets and Other, net		1
Operating Income		252	168	590	457
Other Income and Expenses
Total other income and expenses		12	9	31	28
Interest Expense		49	29	148	114
Income Before Income Taxes		215	148	473	371
Income Tax Expense (Benefit)		34	29	77	72
Net Income and Comprehensive Income		181	119	396	299
Piedmont
Operating Revenues
Total operating revenues		195	162	1,016	871
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		66	39	354	254
Operation, maintenance and other		77	75	231	234
Depreciation and amortization		51	45	150	133
Property and other taxes		16	13	44	37
Impairment of assets and other charges		4	7	9	7
Total operating expenses		214	179	788	665
Operating Income		(19)	(17)	228	206
Other Income and Expenses
Equity in earnings (losses) of unconsolidated affiliates				7	7
Total other income and expenses		16	16	51	44
Interest Expense		29	29	88	89
Income Before Income Taxes		(32)	(30)	191	161
Income Tax Expense (Benefit)		(8)	(5)	16	6
Net Income and Comprehensive Income		(24)	(25)	175	155
Fuel used in electric generation and purchased power
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		1,844	1,849	4,702	4,645
Fuel used in electric generation and purchased power | Duke Energy Ohio
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		119	94	294	258
Cost of natural gas
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		75	41	430	299
Cost of natural gas | Duke Energy Ohio
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		$ 9	$ 3	$ 76	$ 46
[1]	Net of income tax impacts of approximately $24 million for the three months ended September 30, 2020, and $16 million and $43 million for the nine months ended September 30, 2021, and 2020, respectively. All other periods presented include immaterial income tax impacts.

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract]
Net income (loss)		$ 1,276	$ 1,234	$ 2,915	$ 1,232
Other Comprehensive Income (Loss), net of tax
Pension and OPEB adjustments	[1]	1	1	3	1
Net unrealized gains (losses) on cash flow hedges	[1]	9	(83)	(59)	(159)
Reclassification into earnings from cash flow hedges	[1]	2	4	9	8
Unrealized (losses) gains on available-for-sale securities	[1]	(2)	(2)	(6)	5
Other Comprehensive Income (Loss), net of tax	[1]	10	(80)	(53)	(145)
Comprehensive Income		1,286	1,154	2,862	1,087
Add: Comprehensive Loss Attributable to Noncontrolling Interests		128	70	240	220
Comprehensive Income Attributable to Duke Energy		1,414	1,224	3,102	1,307
Less: Preferred Dividends		39	39	92	93
Comprehensive Income Available to Duke Energy Corporation Common Stockholders		$ 1,375	$ 1,185	$ 3,010	$ 1,214
[1]	Net of income tax impacts of approximately $24 million for the three months ended September 30, 2020, and $16 million and $43 million for the nine months ended September 30, 2021, and 2020, respectively. All other periods presented include immaterial income tax impacts.

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Other comprehensive income (loss), tax	$ 24	$ 16	$ 43

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Current Assets
Cash and cash equivalents	$ 548	$ 259
Receivables of VIEs (net of allowance for doubtful accounts)	998	1,009
Receivables (net of allowance for doubtful accounts)	2,431	2,144
Inventory	2,900	3,167
Regulatory assets (includes amounts related to VIEs)	1,791	1,641
Other (includes amounts related to VIEs)	768	462
Total current assets	9,436	8,682
Property, Plant and Equipment
Cost	160,652	155,580
Accumulated depreciation and amortization	(50,543)	(48,827)
Facilities to be retired, net	127	29
Net property, plant and equipment	110,236	106,782
Other Noncurrent Assets
Goodwill	19,303	19,303
Regulatory assets (includes amounts related to VIEs)	12,247	12,421
Nuclear decommissioning trust funds	9,861	9,114
Operating lease right-of-use assets, net	1,287	1,524
Investments in equity method unconsolidated affiliates	951	961
Other (includes amounts related to VIEs)	3,686	3,601
Total other noncurrent assets	47,335	46,924
Total Assets	167,007	162,388
Current Liabilities
Accounts payable	2,888	3,144
Notes payable and commercial paper	2,098	2,873
Taxes accrued	908	482
Interest accrued	558	537
Current maturities of long-term debt (includes amounts related to VIEs)	4,873	4,238
Asset retirement obligations	673	718
Regulatory liabilities	1,319	1,377
Other	2,239	2,936
Total current liabilities	15,556	16,305
Long-Term Debt (includes amounts related to VIEs)	57,929	55,625
Other Noncurrent Liabilities
Deferred income taxes	9,875	9,244
Asset retirement obligations	12,278	12,286
Regulatory liabilities	15,530	15,029
Operating lease liabilities	1,093	1,340
Accrued pension and other post-retirement benefit costs	988	969
Investment tax credits	804	687
Other (includes amounts related to VIEs)	1,714	1,719
Total other noncurrent liabilities	42,282	41,274
Commitments and Contingencies
Equity
Common stock	1	1
Additional paid-in capital	44,348	43,767
Retained earnings	3,293	2,471
Accumulated other comprehensive loss	(297)	(237)
Total Duke Energy Corporation stockholders' equity	49,307	47,964
Noncontrolling interests	1,933	1,220
Total equity	51,240	49,184
Total Liabilities and Equity	167,007	162,388
Variable Interest Entity
Current Assets
Regulatory assets (includes amounts related to VIEs)	54	53
Other (includes amounts related to VIEs)	347	296
Other Noncurrent Assets
Regulatory assets (includes amounts related to VIEs)	896	937
Other (includes amounts related to VIEs)	134	81
Current Liabilities
Current maturities of long-term debt (includes amounts related to VIEs)	221	472
Long-Term Debt (includes amounts related to VIEs)	3,923	3,535
Other Noncurrent Liabilities
Other (includes amounts related to VIEs)	341	316
Duke Energy Carolinas
Current Assets
Cash and cash equivalents	21	21
Receivables of VIEs (net of allowance for doubtful accounts)	915	696
Receivables (net of allowance for doubtful accounts)	278	247
Receivables from affiliated companies	85	124
Inventory	969	1,010
Regulatory assets (includes amounts related to VIEs)	460	473
Other (includes amounts related to VIEs)	104	20
Total current assets	2,832	2,591
Property, Plant and Equipment
Cost	51,790	50,640
Accumulated depreciation and amortization	(17,959)	(17,453)
Facilities to be retired, net	89
Net property, plant and equipment	33,920	33,187
Other Noncurrent Assets
Regulatory assets (includes amounts related to VIEs)	2,743	2,996
Nuclear decommissioning trust funds	5,434	4,977
Operating lease right-of-use assets, net	95	110
Other (includes amounts related to VIEs)	1,197	1,187
Total other noncurrent assets	9,469	9,270
Total Assets	46,221	45,048
Current Liabilities
Accounts payable	673	1,000
Accounts payable to affiliated companies	184	199
Notes payable to affiliated companies	86	506
Taxes accrued	391	76
Interest accrued	137	117
Current maturities of long-term debt (includes amounts related to VIEs)	357	506
Asset retirement obligations	245	264
Regulatory liabilities	503	473
Other	516	546
Total current liabilities	3,092	3,687
Long-Term Debt (includes amounts related to VIEs)	12,318	11,412
Long-Term Debt Payable to Affiliated Companies	300	300
Other Noncurrent Liabilities
Deferred income taxes	3,893	3,842
Asset retirement obligations	5,134	5,086
Regulatory liabilities	6,867	6,535
Operating lease liabilities	83	97
Accrued pension and other post-retirement benefit costs	64	73
Investment tax credits	288	236
Other (includes amounts related to VIEs)	558	626
Total other noncurrent liabilities	16,887	16,495
Commitments and Contingencies
Equity
Member's equity	13,631	13,161
Accumulated other comprehensive loss	(7)	(7)
Member's Equity	13,624	13,154
Total Liabilities and Equity	46,221	45,048
Progress Energy
Current Assets
Cash and cash equivalents	102	59
Receivables of VIEs (net of allowance for doubtful accounts)	981	901
Receivables (net of allowance for doubtful accounts)	268	228
Receivables from affiliated companies	61	157
Inventory	1,255	1,375
Regulatory assets (includes amounts related to VIEs)	864	758
Other (includes amounts related to VIEs)	178	109
Total current assets	3,709	3,587
Property, Plant and Equipment
Cost	59,976	57,892
Accumulated depreciation and amortization	(19,211)	(18,368)
Facilities to be retired, net	27	29
Net property, plant and equipment	40,792	39,553
Other Noncurrent Assets
Goodwill	3,655	3,655
Regulatory assets (includes amounts related to VIEs)	5,785	5,775
Nuclear decommissioning trust funds	4,427	4,137
Operating lease right-of-use assets, net	714	690
Other (includes amounts related to VIEs)	1,175	1,227
Total other noncurrent assets	15,756	15,484
Total Assets	60,257	58,624
Current Liabilities
Accounts payable	898	919
Accounts payable to affiliated companies	221	289
Notes payable to affiliated companies	3,123	2,969
Taxes accrued	284	121
Interest accrued	175	202
Current maturities of long-term debt (includes amounts related to VIEs)	1,932	1,426
Asset retirement obligations	234	283
Regulatory liabilities	541	640
Other	856	793
Total current liabilities	8,264	7,642
Long-Term Debt (includes amounts related to VIEs)	17,406	17,688
Long-Term Debt Payable to Affiliated Companies	150	150
Other Noncurrent Liabilities
Deferred income taxes	4,784	4,396
Asset retirement obligations	5,850	5,866
Regulatory liabilities	5,335	5,051
Operating lease liabilities	623	623
Accrued pension and other post-retirement benefit costs	490	505
Other (includes amounts related to VIEs)	473	462
Total other noncurrent liabilities	17,555	16,903
Commitments and Contingencies
Equity
Additional paid-in capital	9,149	9,143
Retained earnings	7,743	7,109
Accumulated other comprehensive loss	(13)	(15)
Total Duke Energy Corporation stockholders' equity	16,879	16,237
Noncontrolling interests	3	4
Total equity	16,882	16,241
Total Liabilities and Equity	60,257	58,624
Progress Energy | Variable Interest Entity
Current Assets
Regulatory assets (includes amounts related to VIEs)	54	53
Other (includes amounts related to VIEs)	17	39
Other Noncurrent Assets
Regulatory assets (includes amounts related to VIEs)	896	937
Current Liabilities
Current maturities of long-term debt (includes amounts related to VIEs)	56	305
Long-Term Debt (includes amounts related to VIEs)	1,546	1,252
Duke Energy Progress
Current Assets
Cash and cash equivalents	51	39
Receivables of VIEs (net of allowance for doubtful accounts)	532	500
Receivables (net of allowance for doubtful accounts)	162	132
Receivables from affiliated companies	68	50
Inventory	815	911
Regulatory assets (includes amounts related to VIEs)	499	492
Other (includes amounts related to VIEs)	116	60
Total current assets	2,243	2,184
Property, Plant and Equipment
Cost	36,666	35,759
Accumulated depreciation and amortization	(13,365)	(12,801)
Facilities to be retired, net	27	29
Net property, plant and equipment	23,328	22,987
Other Noncurrent Assets
Regulatory assets (includes amounts related to VIEs)	3,955	3,976
Nuclear decommissioning trust funds	3,857	3,500
Operating lease right-of-use assets, net	402	346
Other (includes amounts related to VIEs)	772	740
Total other noncurrent assets	8,986	8,562
Total Assets	34,557	33,733
Current Liabilities
Accounts payable	392	454
Accounts payable to affiliated companies	113	215
Notes payable to affiliated companies	117	295
Taxes accrued	163	85
Interest accrued	68	99
Current maturities of long-term debt (includes amounts related to VIEs)	1,207	603
Asset retirement obligations	234	283
Regulatory liabilities	439	530
Other	442	411
Total current liabilities	3,175	2,975
Long-Term Debt (includes amounts related to VIEs)	8,491	8,505
Long-Term Debt Payable to Affiliated Companies	150	150
Other Noncurrent Liabilities
Deferred income taxes	2,488	2,298
Asset retirement obligations	5,407	5,352
Regulatory liabilities	4,685	4,394
Operating lease liabilities	359	323
Accrued pension and other post-retirement benefit costs	234	242
Investment tax credits	129	132
Other (includes amounts related to VIEs)	79	102
Total other noncurrent liabilities	13,381	12,843
Commitments and Contingencies
Equity
Member's Equity	9,360	9,260
Total Liabilities and Equity	34,557	33,733
Duke Energy Florida
Current Assets
Cash and cash equivalents	40	11
Receivables of VIEs (net of allowance for doubtful accounts)	449	401
Receivables (net of allowance for doubtful accounts)	104	94
Receivables from affiliated companies	3	3
Inventory	439	464
Regulatory assets (includes amounts related to VIEs)	365	265
Other (includes amounts related to VIEs)	35	41
Total current assets	1,435	1,279
Property, Plant and Equipment
Cost	23,300	22,123
Accumulated depreciation and amortization	(5,839)	(5,560)
Net property, plant and equipment	17,461	16,563
Other Noncurrent Assets
Regulatory assets (includes amounts related to VIEs)	1,829	1,799
Nuclear decommissioning trust funds	570	637
Operating lease right-of-use assets, net	312	344
Other (includes amounts related to VIEs)	351	335
Total other noncurrent assets	3,062	3,115
Total Assets	21,958	20,957
Current Liabilities
Accounts payable	506	465
Accounts payable to affiliated companies	129	85
Notes payable to affiliated companies	603	196
Taxes accrued	177	82
Interest accrued	72	69
Current maturities of long-term debt (includes amounts related to VIEs)	276	823
Regulatory liabilities	102	110
Other	403	374
Total current liabilities	2,268	2,204
Long-Term Debt (includes amounts related to VIEs)	7,273	7,092
Other Noncurrent Liabilities
Deferred income taxes	2,382	2,191
Asset retirement obligations	443	514
Regulatory liabilities	649	658
Operating lease liabilities	265	300
Accrued pension and other post-retirement benefit costs	225	231
Other (includes amounts related to VIEs)	265	209
Total other noncurrent liabilities	4,229	4,103
Commitments and Contingencies
Equity
Member's equity	8,190	7,560
Accumulated other comprehensive loss	(2)	(2)
Member's Equity	8,188	7,558
Total Liabilities and Equity	21,958	20,957
Duke Energy Florida | Variable Interest Entity
Current Assets
Regulatory assets (includes amounts related to VIEs)	54	53
Other (includes amounts related to VIEs)	17	39
Other Noncurrent Assets
Regulatory assets (includes amounts related to VIEs)	896	937
Current Liabilities
Current maturities of long-term debt (includes amounts related to VIEs)	56	305
Long-Term Debt (includes amounts related to VIEs)	1,196	1,002
Duke Energy Ohio
Current Assets
Cash and cash equivalents	16	14
Receivables (net of allowance for doubtful accounts)	107	98
Receivables from affiliated companies	77	102
Inventory	114	110
Regulatory assets (includes amounts related to VIEs)	61	39
Other (includes amounts related to VIEs)	45	31
Total current assets	420	394
Property, Plant and Equipment
Cost	11,531	11,022
Accumulated depreciation and amortization	(3,102)	(3,013)
Net property, plant and equipment	8,429	8,009
Other Noncurrent Assets
Goodwill	920	920
Regulatory assets (includes amounts related to VIEs)	634	610
Operating lease right-of-use assets, net	19	20
Other (includes amounts related to VIEs)	83	72
Total other noncurrent assets	1,656	1,622
Total Assets	10,505	10,025
Current Liabilities
Accounts payable	304	279
Accounts payable to affiliated companies	59	68
Notes payable to affiliated companies	451	169
Taxes accrued	210	247
Interest accrued	32	31
Current maturities of long-term debt (includes amounts related to VIEs)	50	50
Asset retirement obligations	17	3
Regulatory liabilities	63	65
Other	68	70
Total current liabilities	1,254	982
Long-Term Debt (includes amounts related to VIEs)	3,017	3,014
Long-Term Debt Payable to Affiliated Companies	25	25
Other Noncurrent Liabilities
Deferred income taxes	1,032	981
Asset retirement obligations	95	108
Regulatory liabilities	734	748
Operating lease liabilities	19	20
Accrued pension and other post-retirement benefit costs	114	113
Other (includes amounts related to VIEs)	92	99
Total other noncurrent liabilities	2,086	2,069
Commitments and Contingencies
Equity
Common stock	762	762
Additional paid-in capital	2,776	2,776
Retained earnings	585	397
Total Duke Energy Corporation stockholders' equity	4,123	3,935
Total Liabilities and Equity	10,505	10,025
Duke Energy Indiana
Current Assets
Cash and cash equivalents	14	7
Receivables (net of allowance for doubtful accounts)	81	55
Receivables from affiliated companies	62	112
Notes receivable from affiliated companies	252
Inventory	367	473
Regulatory assets (includes amounts related to VIEs)	196	125
Other (includes amounts related to VIEs)	59	37
Total current assets	1,031	809
Property, Plant and Equipment
Cost	17,320	17,382
Accumulated depreciation and amortization	(5,550)	(5,661)
Net property, plant and equipment	11,770	11,721
Other Noncurrent Assets
Regulatory assets (includes amounts related to VIEs)	1,300	1,203
Operating lease right-of-use assets, net	51	55
Other (includes amounts related to VIEs)	276	253
Total other noncurrent assets	1,627	1,511
Total Assets	14,428	14,041
Current Liabilities
Accounts payable	239	188
Accounts payable to affiliated companies	198	88
Notes payable to affiliated companies		131
Taxes accrued	83	62
Interest accrued	59	51
Current maturities of long-term debt (includes amounts related to VIEs)	151	70
Asset retirement obligations	177	168
Regulatory liabilities	147	111
Other	104	83
Total current liabilities	1,158	952
Long-Term Debt (includes amounts related to VIEs)	3,791	3,871
Long-Term Debt Payable to Affiliated Companies	150	150
Other Noncurrent Liabilities
Deferred income taxes	1,289	1,228
Asset retirement obligations	966	1,008
Regulatory liabilities	1,573	1,627
Operating lease liabilities	49	53
Accrued pension and other post-retirement benefit costs	172	171
Investment tax credits	172	168
Other (includes amounts related to VIEs)	53	30
Total other noncurrent liabilities	4,274	4,285
Commitments and Contingencies
Equity
Member's Equity	5,055	4,783
Total Liabilities and Equity	14,428	14,041
Piedmont
Current Assets
Receivables (net of allowance for doubtful accounts)	96	250
Receivables from affiliated companies	11	10
Inventory	68	68
Regulatory assets (includes amounts related to VIEs)	125	153
Other (includes amounts related to VIEs)	59	20
Total current assets	359	501
Property, Plant and Equipment
Cost	9,733	9,134
Accumulated depreciation and amortization	(1,862)	(1,749)
Facilities to be retired, net	11
Net property, plant and equipment	7,882	7,385
Other Noncurrent Assets
Goodwill	49	49
Regulatory assets (includes amounts related to VIEs)	335	302
Operating lease right-of-use assets, net	17	20
Investments in equity method unconsolidated affiliates	100	88
Other (includes amounts related to VIEs)	282	270
Total other noncurrent assets	783	729
Total Assets	9,024	8,615
Current Liabilities
Accounts payable	184	230
Accounts payable to affiliated companies	31	79
Notes payable to affiliated companies	315	530
Taxes accrued	41	23
Interest accrued	35	34
Current maturities of long-term debt (includes amounts related to VIEs)		160
Regulatory liabilities	64	88
Other	76	69
Total current liabilities	746	1,213
Long-Term Debt (includes amounts related to VIEs)	2,968	2,620
Other Noncurrent Liabilities
Deferred income taxes	875	821
Asset retirement obligations	21	20
Regulatory liabilities	1,004	1,044
Operating lease liabilities	15	19
Accrued pension and other post-retirement benefit costs	6	8
Other (includes amounts related to VIEs)	175	155
Total other noncurrent liabilities	2,096	2,067
Commitments and Contingencies
Equity
Common stock	1,635	1,310
Retained earnings	1,579	1,405
Total Duke Energy Corporation stockholders' equity	3,214	2,715
Total Liabilities and Equity	9,024	8,615
Preferred stock, Series A
Equity
Preferred stock	973	973
Preferred stock, Series B
Equity
Preferred stock	$ 989	$ 989

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Allowance for doubtful accounts - receivables	$ 48	$ 29
Regulatory assets (includes amounts related to VIEs)	1,791	1,641
Current Assets: Other	768	462
Regulatory assets (includes amounts related to VIEs)	12,247	12,421
Other Noncurrent Assets: Other	3,686	3,601
Current maturities of long-term debt (includes amounts related to VIEs)	4,873	4,238
Long-Term Debt	57,929	55,625
Other, noncurrent liabilities	$ 1,714	$ 1,719
Common stock, par value (in usd per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	2,000,000,000	2,000,000,000
Common stock, shares outstanding (in shares)	769,000,000	769,000,000
Preferred stock, Series A
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
Preferred stock, Series B
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
Variable Interest Entity
Allowance for doubtful accounts - receivables of VIEs	$ 75	$ 117
Regulatory assets (includes amounts related to VIEs)	54	53
Current Assets: Other	347	296
Regulatory assets (includes amounts related to VIEs)	896	937
Other Noncurrent Assets: Other	134	81
Current maturities of long-term debt (includes amounts related to VIEs)	221	472
Long-Term Debt	3,923	3,535
Other, noncurrent liabilities	341	316
Duke Energy Carolinas
Allowance for doubtful accounts - receivables	2	1
Allowance for doubtful accounts - receivables of VIEs	40	22
Regulatory assets (includes amounts related to VIEs)	460	473
Current Assets: Other	104	20
Regulatory assets (includes amounts related to VIEs)	2,743	2,996
Other Noncurrent Assets: Other	1,197	1,187
Current maturities of long-term debt (includes amounts related to VIEs)	357	506
Long-Term Debt	12,318	11,412
Other, noncurrent liabilities	558	626
Progress Energy
Allowance for doubtful accounts - receivables	11	8
Regulatory assets (includes amounts related to VIEs)	864	758
Current Assets: Other	178	109
Regulatory assets (includes amounts related to VIEs)	5,785	5,775
Other Noncurrent Assets: Other	1,175	1,227
Current maturities of long-term debt (includes amounts related to VIEs)	1,932	1,426
Long-Term Debt	17,406	17,688
Other, noncurrent liabilities	$ 473	$ 462
Common stock, par value (in 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 | Variable Interest Entity
Allowance for doubtful accounts - receivables of VIEs	$ 25	$ 29
Regulatory assets (includes amounts related to VIEs)	54	53
Current Assets: Other	17	39
Regulatory assets (includes amounts related to VIEs)	896	937
Current maturities of long-term debt (includes amounts related to VIEs)	56	305
Long-Term Debt	1,546	1,252
Duke Energy Progress
Allowance for doubtful accounts - receivables	4	4
Regulatory assets (includes amounts related to VIEs)	499	492
Current Assets: Other	116	60
Regulatory assets (includes amounts related to VIEs)	3,955	3,976
Other Noncurrent Assets: Other	772	740
Current maturities of long-term debt (includes amounts related to VIEs)	1,207	603
Long-Term Debt	8,491	8,505
Other, noncurrent liabilities	79	102
Duke Energy Progress | Variable Interest Entity
Allowance for doubtful accounts - receivables of VIEs	17	19
Duke Energy Florida
Allowance for doubtful accounts - receivables	8	4
Regulatory assets (includes amounts related to VIEs)	365	265
Current Assets: Other	35	41
Regulatory assets (includes amounts related to VIEs)	1,829	1,799
Other Noncurrent Assets: Other	351	335
Current maturities of long-term debt (includes amounts related to VIEs)	276	823
Long-Term Debt	7,273	7,092
Other, noncurrent liabilities	265	209
Duke Energy Florida | Variable Interest Entity
Allowance for doubtful accounts - receivables of VIEs	8	10
Regulatory assets (includes amounts related to VIEs)	54	53
Current Assets: Other	17	39
Regulatory assets (includes amounts related to VIEs)	896	937
Current maturities of long-term debt (includes amounts related to VIEs)	56	305
Long-Term Debt	1,196	1,002
Duke Energy Ohio
Allowance for doubtful accounts - receivables	4	4
Regulatory assets (includes amounts related to VIEs)	61	39
Current Assets: Other	45	31
Regulatory assets (includes amounts related to VIEs)	634	610
Other Noncurrent Assets: Other	83	72
Current maturities of long-term debt (includes amounts related to VIEs)	50	50
Long-Term Debt	3,017	3,014
Other, noncurrent liabilities	$ 92	$ 99
Common stock, par value (in 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 (includes amounts related to VIEs)	196	125
Current Assets: Other	59	37
Regulatory assets (includes amounts related to VIEs)	1,300	1,203
Other Noncurrent Assets: Other	276	253
Current maturities of long-term debt (includes amounts related to VIEs)	151	70
Long-Term Debt	3,791	3,871
Other, noncurrent liabilities	53	30
Piedmont
Allowance for doubtful accounts - receivables	15	12
Regulatory assets (includes amounts related to VIEs)	125	153
Current Assets: Other	59	20
Regulatory assets (includes amounts related to VIEs)	335	302
Other Noncurrent Assets: Other	282	270
Current maturities of long-term debt (includes amounts related to VIEs)		160
Long-Term Debt	2,968	2,620
Other, noncurrent liabilities	$ 175	$ 155
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares outstanding (in shares)	100,000,000	100,000,000

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 2,915	$ 1,232
Net income	3,162	1,440
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	4,189	4,081
Equity in (earnings) losses of unconsolidated affiliates	(14)	2,004
Equity component of AFUDC	(126)	(112)
Impairment of assets and other charges	342	36
Deferred income taxes	206	210
Payments for asset retirement obligations	(389)	(463)
Provision for rate refunds	(41)	(15)
Refund of AMT credit carryforwards		572
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	116	87
Receivables	(167)	58
Inventory	268	43
Other current assets	(643)	199
Increase (decrease) in
Accounts payable	(146)	(563)
Taxes accrued	431	386
Other current liabilities	10	(284)
Other assets	199	(338)
Other liabilities	77	(367)
Net cash provided by operating activities	7,227	6,766
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(7,089)	(7,408)
Contributions to equity method investments	(30)	(276)
Purchases of debt and equity securities	(4,292)	(6,160)
Proceeds from sales and maturities of debt and equity securities	4,335	6,087
Disbursements to canceled equity method investments	(855)
Other	(269)	(207)
Net cash used in investing activities	(8,200)	(7,964)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	6,379	6,162
Proceeds from the issuance of common stock	5	75
Payments for the redemption of long-term debt	(3,696)	(3,468)
Proceeds from the issuance of short-term debt with original maturities greater than 90 days	109	2,372
Payments for the redemption of short-term debt with original maturities greater than 90 days	(997)	(1,143)
Notes payable and commercial paper	165	(969)
Contributions from noncontrolling interests	1,556	402
Dividends paid	(2,340)	(2,113)
Other	(21)	(93)
Net cash provided by financing activities	1,160	1,225
Net increase in cash, cash equivalents and restricted cash	187	27
Cash, cash equivalents and restricted cash at beginning of period	556	573
Cash, cash equivalents and restricted cash at end of period	743	600
Significant non-cash transactions:
Accrued capital expenditures	998	992
Non-cash dividends		82
Duke Energy Carolinas
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	1,070	1,128
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	1,295	1,295
Equity component of AFUDC	(46)	(46)
Loss on sales of other assets	(1)
Impairment of assets and other charges	238	22
Deferred income taxes	(146)	(103)
Payments for asset retirement obligations	(132)	(127)
Provision for rate refunds	(29)	(1)
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	(1)
Receivables	(172)	41
Receivables from affiliated companies	39	50
Inventory	41	4
Other current assets	(153)	197
Increase (decrease) in
Accounts payable	(254)	(313)
Accounts payable to affiliated companies	(15)	(55)
Taxes accrued	315	352
Other current liabilities	72	(121)
Other assets	52	(72)
Other liabilities	167	(23)
Net cash provided by operating activities	2,340	2,228
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(1,947)	(1,931)
Purchases of debt and equity securities	(2,465)	(1,313)
Proceeds from sales and maturities of debt and equity securities	2,465	1,313
Notes receivable from affiliated companies		(65)
Other	(122)	(105)
Net cash used in investing activities	(2,069)	(2,101)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	1,367	965
Payments for the redemption of long-term debt	(616)	(457)
Notes payable to affiliated companies	(421)	(29)
Distributions to parent	(600)	(600)
Other	(1)	(1)
Net cash provided by financing activities	(271)	(122)
Net increase in cash, cash equivalents and restricted cash		5
Cash, cash equivalents and restricted cash at beginning of period	21	18
Cash, cash equivalents and restricted cash at end of period	21	23
Significant non-cash transactions:
Accrued capital expenditures	308	295
Progress Energy
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	1,334	1,233
Net income	1,333	1,232
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	1,707	1,734
Equity component of AFUDC	(37)	(30)
Impairment of assets and other charges	79	1
Deferred income taxes	235	(3)
Payments for asset retirement obligations	(206)	(287)
Provision for rate refunds	(22)	4
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	117	(13)
Receivables	(123)	(207)
Receivables from affiliated companies	96	32
Inventory	120	46
Other current assets	(347)	214
Increase (decrease) in
Accounts payable	79	(124)
Accounts payable to affiliated companies	(68)	(102)
Taxes accrued	161	263
Other current liabilities	(36)	(41)
Other assets	(3)	(154)
Other liabilities	(139)	(102)
Net cash provided by operating activities	2,947	2,464
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(2,628)	(2,602)
Purchases of debt and equity securities	(1,583)	(4,554)
Proceeds from sales and maturities of debt and equity securities	1,649	4,543
Notes receivable from affiliated companies		164
Other	(131)	(114)
Net cash used in investing activities	(2,693)	(2,563)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	1,190	1,791
Payments for the redemption of long-term debt	(977)	(1,555)
Notes payable to affiliated companies	154	338
Dividends to parent	(700)	(400)
Other	(2)	(13)
Net cash provided by financing activities	(335)	161
Net increase in cash, cash equivalents and restricted cash	(81)	62
Cash, cash equivalents and restricted cash at beginning of period	200	126
Cash, cash equivalents and restricted cash at end of period	119	188
Significant non-cash transactions:
Accrued capital expenditures	290	311
Duke Energy Progress
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	800	711
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	951	972
Equity component of AFUDC	(25)	(22)
Impairment of assets and other charges	60	5
Deferred income taxes	22	(33)
Payments for asset retirement obligations	(129)	(249)
Provision for rate refunds	(22)	4
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	108
Receivables	(66)	(34)
Receivables from affiliated companies	(18)	7
Inventory	95	24
Other current assets	(79)	82
Increase (decrease) in
Accounts payable	20	(185)
Accounts payable to affiliated companies	(102)	(59)
Taxes accrued	75	190
Other current liabilities	(36)	(24)
Other assets	48	(185)
Other liabilities	(32)	21
Net cash provided by operating activities	1,670	1,225
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(1,313)	(1,142)
Purchases of debt and equity securities	(1,306)	(1,269)
Proceeds from sales and maturities of debt and equity securities	1,291	1,238
Other	(36)	(31)
Net cash used in investing activities	(1,364)	(1,204)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	1,190	1,296
Payments for the redemption of long-term debt	(605)	(985)
Notes payable to affiliated companies	(178)	101
Distributions to parent	(700)	(400)
Other	(1)	(12)
Net cash provided by financing activities	(294)
Net increase in cash, cash equivalents and restricted cash	12	21
Cash, cash equivalents and restricted cash at beginning of period	39	22
Cash, cash equivalents and restricted cash at end of period	51	43
Significant non-cash transactions:
Accrued capital expenditures	82	124
Duke Energy Florida
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	631	623
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	752	755
Equity component of AFUDC	(12)	(8)
Impairment of assets and other charges	19	(4)
Deferred income taxes	207	19
Payments for asset retirement obligations	(77)	(38)
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	7	(17)
Receivables	(57)	(172)
Receivables from affiliated companies		(3)
Inventory	25	22
Other current assets	(247)	41
Increase (decrease) in
Accounts payable	59	63
Accounts payable to affiliated companies	44	(54)
Taxes accrued	95	217
Other current liabilities	(5)	(20)
Other assets	(46)	48
Other liabilities	(94)	(136)
Net cash provided by operating activities	1,301	1,336
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(1,316)	(1,460)
Purchases of debt and equity securities	(277)	(3,284)
Proceeds from sales and maturities of debt and equity securities	358	3,305
Notes receivable from affiliated companies		173
Other	(95)	(82)
Net cash used in investing activities	(1,330)	(1,348)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt		495
Payments for the redemption of long-term debt	(372)	(570)
Notes payable to affiliated companies	408	66
Net cash provided by financing activities	36	(9)
Net increase in cash, cash equivalents and restricted cash	7	(21)
Cash, cash equivalents and restricted cash at beginning of period	50	56
Cash, cash equivalents and restricted cash at end of period	57	35
Significant non-cash transactions:
Accrued capital expenditures	208	187
Duke Energy Ohio
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	188	201
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	231	211
Equity component of AFUDC	(5)	(4)
Impairment of assets and other charges	5
Deferred income taxes	27	31
Payments for asset retirement obligations	(1)	(1)
Provision for rate refunds	12	10
(Increase) decrease in
Receivables	(9)	(5)
Receivables from affiliated companies	(11)	35
Inventory	(4)	5
Other current assets	(34)	5
Increase (decrease) in
Accounts payable	27	(28)
Accounts payable to affiliated companies	(9)	(14)
Taxes accrued	(37)	(23)
Other current liabilities	(12)	6
Other assets	(35)	(24)
Other liabilities	8	(7)
Net cash provided by operating activities	341	398
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(615)	(611)
Notes receivable from affiliated companies	36
Other	(42)	(34)
Net cash used in investing activities	(621)	(645)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt		467
Notes payable to affiliated companies	282	(227)
Net cash provided by financing activities	282	240
Net increase in cash, cash equivalents and restricted cash	2	(7)
Cash, cash equivalents and restricted cash at beginning of period	14	17
Cash, cash equivalents and restricted cash at end of period	16	10
Significant non-cash transactions:
Accrued capital expenditures	103	92
Duke Energy Indiana
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	396	299
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	460	416
Equity component of AFUDC	(19)	(18)
Impairment of assets and other charges	8
Deferred income taxes	19	11
Payments for asset retirement obligations	(49)	(48)
(Increase) decrease in
Receivables	(7)	15
Receivables from affiliated companies	17	(5)
Inventory	106	10
Other current assets	(58)	12
Increase (decrease) in
Accounts payable	46	(1)
Accounts payable to affiliated companies	(15)	(22)
Taxes accrued	25	65
Other current liabilities	23	(2)
Other assets	11	(41)
Other liabilities	3	104
Net cash provided by operating activities	966	795
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(584)	(669)
Purchases of debt and equity securities	(34)	(24)
Proceeds from sales and maturities of debt and equity securities	16	15
Notes receivable from affiliated companies	(218)
Other	(8)	(24)
Net cash used in investing activities	(828)	(702)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt		544
Payments for the redemption of long-term debt		(500)
Notes payable to affiliated companies	(131)	53
Distributions to parent		(200)
Net cash provided by financing activities	(131)	(103)
Net increase in cash, cash equivalents and restricted cash	7	(10)
Cash, cash equivalents and restricted cash at beginning of period	7	25
Cash, cash equivalents and restricted cash at end of period	14	15
Significant non-cash transactions:
Accrued capital expenditures	105	73
Piedmont
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	175	155
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	152	135
Equity in (earnings) losses of unconsolidated affiliates	(7)	(7)
Equity component of AFUDC	(19)	(14)
Impairment of assets and other charges	10	7
Deferred income taxes	10	24
Provision for rate refunds	(3)	(27)
(Increase) decrease in
Receivables	151	164
Receivables from affiliated companies	(1)	(1)
Inventory		25
Other current assets	7	(59)
Increase (decrease) in
Accounts payable	(55)	(53)
Accounts payable to affiliated companies	(48)	60
Taxes accrued	17	16
Other current liabilities	(32)	(4)
Other assets	3	(14)
Other liabilities	2	7
Net cash provided by operating activities	362	414
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(628)	(641)
Contributions to equity method investments	(9)
Return of investment capital	1
Other	(23)	(18)
Net cash used in investing activities	(659)	(659)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	347	394
Payments for the redemption of long-term debt	(160)
Notes payable to affiliated companies	(215)	(149)
Capital contributions from parent	325
Net cash provided by financing activities	297	245
Significant non-cash transactions:
Accrued capital expenditures	$ 115	$ 123

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Changes in Equity - USD ($) $ in Millions		Total		Preferred Stock	Common Stockholders' Equity		Additional Paid-in Capital		Retained Earnings		Accumulated Other Comprehensive (Loss) Income, Net (Losses) Gains on Cash Flow Hedges	Accumulated Other Comprehensive (Loss) Income, Net Unrealized (Losses) Gains on Available-for-Sale-Securities	Accumulated Other Comprehensive (Loss) Income, Pension and OPEB Adjustments	Noncontrolling Interests	Duke Energy Carolinas		Duke Energy CarolinasMember's Equity		Duke Energy CarolinasAccumulated Other Comprehensive (Loss) Income, Net (Losses) Gains on Cash Flow Hedges	Progress Energy	Progress EnergyCommon Stockholders' Equity	Progress EnergyAdditional Paid-in Capital	Progress EnergyRetained Earnings	Progress EnergyAccumulated Other Comprehensive (Loss) Income, Net (Losses) Gains on Cash Flow Hedges	Progress EnergyAccumulated Other Comprehensive (Loss) Income, Net Unrealized (Losses) Gains on Available-for-Sale-Securities	Progress EnergyAccumulated Other Comprehensive (Loss) Income, Pension and OPEB Adjustments	Progress EnergyNoncontrolling Interests	Duke Energy Progress	Duke Energy ProgressMember's Equity	Duke Energy Florida	Duke Energy FloridaMember's Equity	Duke Energy FloridaAccumulated Other Comprehensive (Loss) Income, Net Unrealized (Losses) Gains 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 IndianaMember's Equity	Piedmont	PiedmontCommon Stock	PiedmontRetained Earnings	Common Stock	Common StockCommon Stockholders' Equity	Common StockCommon Stock	Common StockAdditional Paid-in Capital
Beginning Balance at Dec. 31, 2019		$ 47,951		$ 1,962	$ 46,822		$ 40,881		$ 4,108		$ (51)	$ 3	$ (82)	$ 1,129						$ 15,593	$ 15,590	$ 9,143	$ 6,465	$ (10)	$ (1)	$ (7)	$ 3																	$ 1
Beginning Balance, in shares at Dec. 31, 2019																																												733,000,000
Beginning Balance (member's equity) at Dec. 31, 2019															$ 12,811		$ 12,818		$ (7)										$ 9,246	$ 6,788	$ 6,789	$ (1)						$ 4,575
Beginning Balance (parent) at Dec. 31, 2019																																	$ 3,683	$ 762	$ 2,776	$ 145			$ 2,443	$ 1,310	$ 1,133
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		1,139			1,347				1,347					(208)
Net income		1,440													1,128		1,128			1,232								$ 711	711	623	623		201			201	$ 299	299	155		155
Net income		1,232																		1,233	1,232		1,232				1
Other comprehensive (loss) income		(145)	[1]		(133)						(139)	5	1	(12)						5	5			3	1	1				1		1
Common stock issuances, including dividend reinvestment and employee benefits																																										$ 181	$ 181		$ 181
Common stock issuances, including dividend reinvestment and employee benefits (in shares)																																												3,000,000
Common stock dividends		(2,103)			(2,103)				(2,103)						(600)		(600)			(400)	(400)		(400)						(400)									(200)
Contributions from noncontrolling interests, net of transaction costs	[2]	385			(17)		(17)							402
Distributions to noncontrolling interest in subsidiaries		(22)												(22)						(1)							(1)
Other		(91)	[3]		(91)	[3]	1	[3]	(92)	[3]					(13)	[4]	(13)	[4]		(1)	(1)		(1)						(1)	(1)	(1)								(1)		(1)
Ending Balance at Sep. 30, 2020		47,295		1,962	46,006		41,046		3,260		(190)	8	(81)	1,289						16,429	16,426	9,143	7,296	(7)		(6)	3																	$ 1
Ending Balance (member's equity) at Sep. 30, 2020															13,326		13,333		(7)										9,556	7,411	7,411							4,674
Ending Balance, in shares at Sep. 30, 2020																																												736,000,000
Ending Balance (parent) at Sep. 30, 2020																																	3,884	762	2,776	346			2,597	1,310	1,287
Beginning Balance at Jun. 30, 2020		46,611		1,962	45,484		40,997		2,707		(111)	10	(82)	1,127						16,221	16,218	9,143	7,090	(8)	(1)	(6)	3																	$ 1
Beginning Balance, in shares at Jun. 30, 2020																																												735,000,000
Beginning Balance (member's equity) at Jun. 30, 2020															13,072		13,079		(7)										9,610	7,124	7,125	(1)						4,655
Beginning Balance (parent) at Jun. 30, 2020																																	3,814	762	2,776	276			2,622	1,310	1,312
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		1,195			1,265				1,265					(70)
Net income		1,304													555		555			605								346	346	287	287		70			70	119	119	(25)		(25)
Net income		1,234																		606	605		605				1
Other comprehensive (loss) income		(80)	[1]		(80)						(79)	(2)	1							2	2			1	1					1		1
Common stock issuances, including dividend reinvestment and employee benefits																																										65	65		65
Common stock issuances, including dividend reinvestment and employee benefits (in shares)																																												1,000,000
Common stock dividends		(712)			(712)				(712)						(300)		(300)			(400)	(400)		(400)						(400)									(100)
Contributions from noncontrolling interests, net of transaction costs	[2]	222			(17)		(17)							239
Distributions to noncontrolling interest in subsidiaries		(8)												(8)
Other		2			1		1							1	(1)		(1)				1		1				(1)			(1)	(1)
Ending Balance at Sep. 30, 2020		47,295		1,962	46,006		41,046		3,260		(190)	8	(81)	1,289						16,429	16,426	9,143	7,296	(7)		(6)	3																	$ 1
Ending Balance (member's equity) at Sep. 30, 2020															13,326		13,333		(7)										9,556	7,411	7,411							4,674
Ending Balance, in shares at Sep. 30, 2020																																												736,000,000
Ending Balance (parent) at Sep. 30, 2020																																	$ 3,884	762	2,776	346			$ 2,597	1,310	1,287
Beginning Balance at Dec. 31, 2020		$ 49,184		1,962	47,964		43,767		2,471		(167)	6	(76)	1,220						$ 16,241	16,237	9,143	7,109	(5)	(2)	(8)	4																	$ 1
Beginning Balance, in shares at Dec. 31, 2020		769,000,000																		100													90,000,000						100,000,000					769,000,000
Beginning Balance (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
Beginning Balance (parent) at Dec. 31, 2020		$ 47,964																		$ 16,237													$ 3,935	762	2,776	397			$ 2,715	1,310	1,405
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		2,823			3,070				3,070					(247)
Net income		3,162													1,070		1,070			1,333								800	800	631	631		$ 188			188	396	396	175		175
Net income		2,915																		1,334	1,333		1,333				1
Other comprehensive (loss) income		(53)	[1]		(60)						(57)	(6)	3	7						2	2			2
Common stock issuances, including dividend reinvestment and employee benefits																																										43	43		43
Common stock dividends		(2,248)			(2,248)				(2,248)						(600)		(600)			(700)	(700)		(700)						(700)									(125)
Sale of noncontrolling interest	[5]	999			545		545							454
Contributions from noncontrolling interests, net of transaction costs	[2]	525			(6)		(6)							531
Distributions to noncontrolling interest in subsidiaries		(34)												(34)						(1)							(1)
Other		1			(1)		(1)							2						6	7	6	1				(1)			(1)	(1)							1	(1)		(1)
Contribution from parent																																							$ 325	325
Ending Balance at Sep. 30, 2021		$ 51,240		1,962	49,307		44,348		3,293		(224)		(73)	1,933						$ 16,882	16,879	9,149	7,743	(3)	(2)	(8)	3																	$ 1
Ending Balance (member's equity) at Sep. 30, 2021															13,624		13,631		(7)									9,360	9,360	8,188	8,190	(2)					5,055	5,055
Ending Balance, in shares at Sep. 30, 2021		769,000,000																		100													90,000,000						100,000,000					769,000,000
Ending Balance (parent) at Sep. 30, 2021		$ 49,307																		$ 16,879													$ 4,123	762	2,776	585			$ 3,214	1,635	1,579
Beginning Balance at Jun. 30, 2021		49,545		1,962	48,132		43,788		2,687		(234)	2	(74)	1,413						16,942	16,939	9,143	7,809	(4)	(2)	(7)	3																	$ 1
Beginning Balance, in shares at Jun. 30, 2021																																												769,000,000
Beginning Balance (member's equity) at Jun. 30, 2021															13,392		13,399		(7)										9,685	7,891	7,893	(2)						4,999
Beginning Balance (parent) at Jun. 30, 2021																																	4,065	762	2,776	527			3,239	1,635	1,604
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		1,237			1,366				1,366					(129)
Net income		1,405													533		533			632								375	375	297	297		$ 58			58	181	181	(24)		(24)
Net income		1,276																		633	632		632				1
Other comprehensive (loss) income		10	[1]		9						10	$ (2)	1	1										1		(1)
Common stock issuances, including dividend reinvestment and employee benefits																																										$ 20	$ 20		$ 20
Common stock dividends		(760)			(760)				(760)						(300)		(300)			(700)	(700)		(700)						(700)									(125)
Sale of noncontrolling interest	[5]	999			545		545							454
Contributions from noncontrolling interests, net of transaction costs	[2]	210			(3)		(3)							213
Distributions to noncontrolling interest in subsidiaries		(22)												(22)
Other		1			(2)		(2)							3	(1)		(1)			7	8	6	2				(1)												$ (1)		(1)
Ending Balance at Sep. 30, 2021		$ 51,240		$ 1,962	$ 49,307		$ 44,348		$ 3,293		$ (224)		$ (73)	$ 1,933						$ 16,882	$ 16,879	$ 9,149	$ 7,743	$ (3)	$ (2)	$ (8)	$ 3																	$ 1
Ending Balance (member's equity) at Sep. 30, 2021															$ 13,624		$ 13,631		$ (7)									$ 9,360	$ 9,360	$ 8,188	$ 8,190	$ (2)					$ 5,055	$ 5,055
Ending Balance, in shares at Sep. 30, 2021		769,000,000																		100													90,000,000						100,000,000					769,000,000
Ending Balance (parent) at Sep. 30, 2021		$ 49,307																		$ 16,879													$ 4,123	$ 762	$ 2,776	$ 585			$ 3,214	$ 1,635	$ 1,579
[1]	Net of income tax impacts of approximately $24 million for the three months ended September 30, 2020, and $16 million and $43 million for the nine months ended September 30, 2021, and 2020, respectively. All other periods presented include immaterial income tax impacts.
[2]	Relates to tax equity financing activity in the Commercial Renewables segment.
[3]	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.
[4]	Amounts primarily represent impacts due to implementation of a new accounting standard related to Current Estimated Credit Losses. See Note 1 for additional discussion.
[5]	Relates to the sale of a noncontrolling interest in Duke Energy Indiana. See Note 2 for additional discussion.

Organization and Basis of Prese

Organization and Basis of Presentation	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	Index to Combined Notes to Condensed Consolidated Financial Statements The unaudited notes to the Condensed Consolidated Financial Statements that follow are a combined presentation. The following list indicates the registrants to which the footnotes apply. Applicable Notes Registrant 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 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. BASIS OF PRESENTATION These Condensed Consolidated Financial Statements have been prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Regulation S-X. Accordingly, these Condensed Consolidated Financial Statements do not include all information and notes required by GAAP for annual financial statements and should be read in conjunction with the Consolidated Financial Statements in the Duke Energy Registrants’ combined Annual Report on Form 10-K for the year ended December 31, 2020. The information in these combined notes relates to each of the Duke Energy Registrants as noted in the Index to Combined Notes to Condensed Consolidated Financial Statements. However, none of the registrants make any representations as to information related solely to Duke Energy or the subsidiaries of Duke Energy other than itself. These Condensed Consolidated Financial Statements, in the opinion of the respective companies’ management, reflect all normal recurring adjustments necessary to fairly present the financial position and results of operations of each of the Duke Energy Registrants. Amounts reported in Duke Energy’s interim Condensed Consolidated Statements of Operations and each of the Subsidiary Registrants’ interim Condensed Consolidated Statements of Operations and Comprehensive Income are not necessarily indicative of amounts expected for the respective annual periods due to effects of seasonal temperature variations on energy consumption, regulatory rulings, timing of maintenance on electric generating units, changes in mark-to-market valuations, changing commodity prices and other factors. In preparing financial statements that conform to GAAP, management 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. BASIS OF CONSOLIDATION These Condensed 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 11 for additional information on VIEs. These Condensed Consolidated Financial Statements also reflect the Duke Energy Registrants’ proportionate share of certain jointly owned generation and transmission facilities. OTHER CURRENT LIABILITIES Included in Other within Current Liabilities on the Duke Energy Condensed Consolidated Balance Sheet is a current liability of $36 million and $936 million as of September 30, 2021, and December 31, 2020, respectively. The current liability, initially recorded in 2020, primarily represented Duke Energy's share of ACP's obligations of outstanding debt and to satisfy ARO requirements to restore construction sites. See Notes 3 and 11 for further information. 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 Condensed Consolidated Balance Sheet. Several operating agreements of Duke Energy's subsidiaries with noncontrolling interest are subject to allocations of earnings, 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 Hypothetical Liquidation at Book Value (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 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. During September 2021, Duke Energy completed the initial minority interest investment in a portion of Duke Energy Indiana to an affiliate of GIC. GIC's ownership interest in Duke Energy Indiana represents a noncontrolling interest. See Note 2 for additional information on the sale. 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 . The following table presents allocated losses to noncontrolling interest for the three and nine months ended September 30, 2021, and 2020. Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2021 2020 2021 2020 Noncontrolling Interest Allocation of Income Allocated losses to noncontrolling tax equity members utilizing the HLBV method $ 119 $ 59 $ 217 $ 187 Allocated losses to noncontrolling members based on pro rata shares of ownership 10 11 30 21 Total Noncontrolling Interest Allocated Losses $ 129 $ 70 $ 247 $ 208 CASH, CASH EQUIVALENTS AND RESTRICTED CASH Duke Energy, Progress Energy and Duke Energy Florida have restricted cash balances related primarily to collateral assets, escrow deposits and VIEs. See Notes 9 and 11 for additional information. Restricted cash amounts are included in Other within Current Assets and Other Noncurrent Assets on the Condensed Consolidated Balance Sheets. The following table presents the components of cash, cash equivalents and restricted cash included in the Condensed Consolidated Balance Sheets. September 30, 2021 December 31, 2020 Duke Duke Duke Progress Energy Duke Progress Energy Energy Energy Florida Energy Energy Florida Current Assets Cash and cash equivalents $ 548 $ 102 $ 40 $ 259 $ 59 $ 11 Other 194 17 17 194 39 39 Other Noncurrent Assets Other 1 — — 103 102 — Total cash, cash equivalents and restricted cash $ 743 $ 119 $ 57 $ 556 $ 200 $ 50 INVENTORY Provisions for inventory write-offs were not material at September 30, 2021, and December 31, 2020. The components of inventory are presented in the tables below. September 30, 2021 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 $ 2,317 $ 779 $ 1,009 $ 674 $ 336 $ 85 $ 305 $ 11 Coal 312 152 89 45 43 10 61 — Natural gas, oil and other fuel 271 38 157 96 60 19 1 57 Total inventory $ 2,900 $ 969 $ 1,255 $ 815 $ 439 $ 114 $ 367 $ 68 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 fuel 294 39 183 107 76 16 1 56 Total inventory $ 3,167 $ 1,010 $ 1,375 $ 911 $ 464 $ 110 $ 473 $ 68 PROPERTY, PLANT & EQUIPMENT AND LEASES Duke Energy continues to execute on its business transformation strategy, including the evaluation of in-office work policies considering the experience with the COVID-19 pandemic and also workforce realignment of roles and responsibilities. In May 2021, Duke Energy management approved the sale of certain properties and entered into an agreement to exit certain leased space on December 31, 2021. The sale of the properties is subject to abandonment accounting and resulted in an impairment charge. Additionally, the exit of the leased space resulted in the impairment of related furniture, fixtures and equipment. The total 2021 charges related to the reduction in physical workspace, including these impairments, are expected to be approximat ely $200 million. During the three months ended September 30, 2021, Duke Energy recorded a pretax charge to earnings of $9 million on the Condensed Consolidated Statements of Operations, which includes $8 million within Impairment of assets and other charges and $1 million within Operations, maintenance and other. During the nine months ended September 30, 2021, Duke Energy recorded a pretax charge to earnings of $184 million on the Condensed Consolidated Statements of Operations, which includes $139 million within Impairment of assets and other charges, $28 million within Operations, maintenance and other and $17 million within Depreciation and amortization. NEW ACCOUNTING STANDARDS The following new accounting standard was adopted by the Duke Energy Registrants in 2021. Leases with Variable Lease Payments. In July 2021, the Financial Accounting Standards Board (FASB) issued new accounting guidance requiring lessors to classify a lease with variable lease payments that do not depend on a reference index or rate as an operating lease if both of the following are met: (1) the lease would have to be classified as a sales-type or direct financing lease under prior guidance, and (2) the lessor would have recognized a day-one loss. Duke Energy elected to adopt the guidance immediately upon issuance of the new standard and will be applying the new standard prospectively to new lease arrangements meeting the criteria. Duke Energy does not currently have any lease arrangements that this new accounting guidance will materially impact. The following accounting standard was adopted by the Duke Energy Registrants in 2020. Current Expected 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. Duke Energy recorded cumulative effects of changes in accounting principles related to the adoption of the new credit loss standard for allowances for credit losses of trade and other receivables, insurance receivables and financial guarantees. These amounts are included in the Condensed Consolidated Balance Sheets in Receivables, Receivables of VIEs, Other Noncurrent Assets and Other Noncurrent Liabilities. See Notes 4 and 12 for more information. 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: January 1, 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 The following new accounting standard has been issued but not yet adopted by the Duke Energy Registrants as of September 30, 2021. 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 2022. 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 2022 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 2022. 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.

Business Segments

Business Segments	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Business Segments	BUSINESS SEGMENTS 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 primarily includes Duke Energy's regulated electric utilities in the Carolinas, Florida and the Midwest. On January 28, 2021, Duke Energy executed an agreement providing for an investment by an affiliate of GIC in Duke Energy Indiana in exchange for a 19.9% minority interest issued by Duke Energy Indiana Holdco, LLC, the holding company for Duke Energy Indiana. The transaction will be completed following two closings for an aggregate purchase price of approximately $2 billion. The first closing, which occurred on September 8, 2021, resulted in Duke Energy Indiana Holdco, LLC issuing 11.05% of its membership interests in exchange for approximately $1,025 million or 50% of the purchase price. Duke Energy retained indirect control of these assets, and, therefore, no gain or loss was recognized on the Condensed Consolidated Statements of Operations. The difference between the cash consideration received, net of transaction costs of approximately $27 million, and the carrying value of the noncontrolling interest is $545 million and was recorded as an increase to equity. 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, midstream pipeline and renewable natural gas investments. The Commercial Renewables segment is primarily comprised of nonregulated utility-scale wind and solar generation assets located throughout the U.S. In 2021, Duke Energy continues to monitor recoverability of its renewable merchant plants located in the Electric Reliability Council of Texas West market and in the PJM West market due to fluctuating market pricing and long-term forecasted energy prices. The assets were not impaired as of September 30, 2021, because the carrying value of approximately $206 million continues to approximate the aggregate estimated future undiscounted cash flows. Duke Energy has a 50% ownership interest in these assets. A continued decline in energy market pricing or other factors unfavorably impacting the economics would likely result in a future impairment. 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, Duke Energy’s wholly owned captive insurance company, Bison, and Duke Energy's ownership interest in National Methanol Company. Business segment information is presented in the following tables. Segment assets presented exclude intercompany assets. Three Months Ended September 30, 2021 Electric Gas Total Utilities and Utilities and Commercial Reportable (in millions) Infrastructure Infrastructure Renewables Segments Other Eliminations Total Unaffiliated revenues $ 6,560 $ 266 $ 117 $ 6,943 $ 8 $ — $ 6,951 Intersegment revenues 9 23 — 32 20 (52) — Total revenues $ 6,569 $ 289 $ 117 $ 6,975 $ 28 $ (52) $ 6,951 Segment income (loss) (a) $ 1,425 $ (3) $ 78 $ 1,500 $ (134) $ — $ 1,366 Less: Noncontrolling interests 129 Add: Preferred stock dividend 39 Net Income $ 1,276 Segment assets $ 141,565 $ 14,692 $ 7,037 $ 163,294 $ 3,717 $ (4) $ 167,007 Three Months Ended September 30, 2020 Electric Gas Total Utilities and Utilities and Commercial Reportable (in millions) Infrastructure Infrastructure Renewables Segments Other Eliminations Total Unaffiliated revenues $ 6,371 $ 217 $ 126 $ 6,714 $ 7 $ — $ 6,721 Intersegment revenues 8 24 — 32 17 (49) — Total revenues $ 6,379 $ 241 $ 126 $ 6,746 $ 24 $ (49) $ 6,721 Segment income (loss) (b) $ 1,381 $ (73) $ 60 $ 1,368 $ (103) $ — $ 1,265 Less: Noncontrolling interests 70 Add: Preferred stock dividend 39 Net Income $ 1,234 (a) G as Utilities and Infrastructure includes $3 million, recorded within Equity in earnings (losses) of unconsolidated affiliates on the Condensed Consolidated Statements of Operations, related to gas pipeline investments. See Note 3 for additional information. Other includes $8 million recorded within Impairment of assets and other charges, $1 million within Operations, maintenance and other on the Condensed Consolidated Statements of Operations, related to the workplace and workforce realignment. See Note 1 for additional i nformation. Electric Utilities and Infrastructure includes $160 million recorded within Impairment of assets and other charges, $77 million within Other Income and expenses, $5 million within Operations, maintenance and other, $13 million within Regulated electric operating revenues and $3 million within Interest expense on the Duke Energy Carolinas' Condensed Consolidated Statement of Operations related to the 2018 South Carolina rate cases and the CCR settlement and insurance proceeds distributed in accordance with that agreement; it also includes $42 million recorded within Impairment of assets and other charges, $34 million within Other Income and expenses , $7 million within Operations, maintenance, and other, $15 million within Regulated electric operating revenues and $5 million within Interest expense on the Duke Energy Progress' Condensed Consolidated Statement of Operations. See Notes 3 and 4 for more information. (b) Electric Utilities and Infrastructure includes $19 million recorded within Impairment charges and $8 million recorded within Operations, maintenance and other on the Duke Energy Carolinas' Condensed Consolidated Statements of Operations related to a partial settlement in the Duke Energy Carolinas' 2019 North Carolina rate case and $8 million recorded within Operations, maintenance and other on Duke Energy Progress' Condensed Consolidated Statements of Operation related to a partial settlement in the Duke Energy Progress' 2019 North Carolina rate case. See Note 3 for more information. Additionally, Electric Utilities and Infrastructure includes $5 million of Impairment charges related to gas pipeline assets recorded on Duke Energy Progress' Condensed Consolidated Statement of Operations. Gas Utilities and Infrastructure includes $78 million recorded within Equity in earnings (losses) of unconsolidated affiliates on the Condensed Consolidated Statements of Operations and $7 million in Impairment charges recorded on the Piedmont Condensed Consolidated Statements of Operations related to gas pipeline investments. Nine Months Ended September 30, 2021 Electric Gas Total Utilities and Utilities and Commercial Reportable (in millions) Infrastructure Infrastructure Renewables Segments Other Eliminations Total Unaffiliated revenues $ 17,161 $ 1,323 $ 355 $ 18,839 $ 20 $ — $ 18,859 Intersegment revenues 24 68 — 92 61 (153) — Total revenues $ 17,185 $ 1,391 $ 355 $ 18,931 $ 81 $ (153) $ 18,859 Segment income (loss) (a) $ 3,180 $ 259 $ 152 $ 3,591 $ (521) $ — $ 3,070 Less: Noncontrolling interests 247 Add: Preferred stock dividend 92 Net Income $ 2,915 Nine Months Ended September 30, 2020 Electric Gas Total Utilities and Utilities and Commercial Reportable (in millions) Infrastructure Infrastructure Renewables Segments Other Eliminations Total Unaffiliated revenues $ 16,571 $ 1,122 $ 378 $ 18,071 $ 20 $ — $ 18,091 Intersegment revenues 25 72 — 97 53 (150) — Total revenues $ 16,596 $ 1,194 $ 378 $ 18,168 $ 73 $ (150) $ 18,091 Segment income (loss) (b) $ 2,839 $ (1,400) $ 207 $ 1,646 $ (299) $ — $ 1,347 Less: Noncontrolling interests 208 Add: Preferred stock dividend 93 Net Income $ 1,232 (a) Gas Utilities and Infrastructure includes $19 million, recorded within Equity in earnings (losses) of unconsolidated affiliates on the Condensed Consolidated Statements of Operations, related to gas pipeline investments. See Note 3 for additional information. Commercial Renewables includes a $35 million loss related to Texas Storm Uri, of which ($8 million) is recorded within Nonregulated electric and other revenues, $2 million within Operations, maintenance and other, $29 million within Equity in earnings (losses) of unconsolidated affiliates and $12 million within Loss Attributable to Noncontrolling Interests on the Condensed Consolidated Statements of Operations. See Note 4 for additional information. Other includes $139 million recorded within Impairment of assets and other charges, $28 million within Operations, maintenance and other, and $17 million within Depreciation and amortization on the Condensed Consolidated Statements of Operations, related to the workplace and workplace realignment. See Note 1 for additional information. Electric Utilities and Infrastructure includes $160 million recorded within Impairment of assets and other charges, $77 million within Other Income and expenses, $5 million within Operations, maintenance and other, $13 million within regulated operating revenues and $3 million within interest expense on the Duke Energy Carolinas' Condensed Consolidated Statement of Operations related to the 2018 South Carolina rate cases and the CCR settlement and insurance proceeds distributed in accordance with that agreement; it also includes $42 million recorded within Impairment of assets and other charges, $34 million within Other Income and expenses, $7 million within Operations, maintenance, and other, $15 million within Regulated electric operating revenues and $5 million wit hin interest expense on the Duke Energy Progress' Condensed Consolidated Statement of Operations. See Notes 3 and 4 for more information. (b) Gas Utilities and Infrastructure includes $2 billion recorded within Equity in earnings (losses) of unconsolidated affiliates on the Condensed Consolidated Statements of Operations, related to gas pipeline investments. See Note 3 for additional information. Other includes a $98 million reversal, included in Operations, maintenance and other on the Condensed Consolidated Statements of Operations, of 2018 severance costs due to a partial settlement in the Duke Energy Carolinas' 2019 North Carolina rate case. See Note 3 for additional information. Electric Utilities and Infrastructure includes $19 million recorded within Impairment charges and $8 million recorded within Operations, maintenance and other on the Duke Energy Carolinas' Condensed Consolidated Statements of Operations related to a partial settlement in the Duke Energy Carolinas' 2019 North Carolina rate case and $8 million recorded within Operations, maintenance and other on Duke Energy Progress' Condensed Consolidated Statements of Operation related to a partial settlement in the Duke Energy Progress' 2019 North Carolina rate case. See Note 3 for more information. Additionally, Electric Utilities and Infrastructure includes $5 million of Impairment charges related to gas pipeline assets recorded on Duke Energy Progress' Condensed Consolidated Statement of Operations in the prior year. Duke Energy Ohio Duke Energy Ohio has two reportable segments, Electric Utilities and Infrastructure and Gas Utilities and Infrastructure. The remainder of Duke Energy Ohio's operations is presented as Other. Three Months Ended September 30, 2021 Electric Gas Total Utilities and Utilities and Reportable (in millions) Infrastructure Infrastructure Segments Other Eliminations Total Total revenues $ 413 $ 93 $ 506 $ — $ — $ 506 Segment income/Net (loss) income $ 48 $ 11 $ 59 $ (1) $ — $ 58 Segment assets $ 6,716 $ 3,783 $ 10,499 $ 27 $ (21) $ 10,505 Three Months Ended September 30, 2020 Electric Gas Total Utilities and Utilities and Reportable (in millions) Infrastructure Infrastructure Segments Other Total Total revenues $ 394 $ 79 $ 473 $ — $ 473 Segment income/Net (loss) income $ 63 $ 9 $ 72 $ (2) $ 70 Nine Months Ended September 30, 2021 Electric Gas Total Utilities and Utilities and Reportable (in millions) Infrastructure Infrastructure Segments Other Total Total revenues $ 1,119 $ 375 $ 1,494 $ — $ 1,494 Segment income/Net (loss) income $ 122 $ 77 $ 199 $ (11) $ 188 Nine Months Ended September 30, 2020 Electric Gas Total Utilities and Utilities and Reportable (in millions) Infrastructure Infrastructure Segments Other Total Total revenues $ 1,070 $ 324 $ 1,394 $ — $ 1,394 Segment income/Net (loss) income $ 137 $ 68 $ 205 $ (4) $ 201

Regulatory Matters

Regulatory Matters	9 Months Ended
	Sep. 30, 2021
Regulated Operations [Abstract]
Regulatory Matters	REGULATORY MATTERS 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 under the 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 (ROE) 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. For more information, see Note 4 "Commitments and Contingencies." 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. The Coal Ash Settlement was approved without modification in the NCUC Orders in the 2019 rate cases on March 31, 2021, and April 16, 2021, for Duke Energy Carolinas and Duke Energy Progress, respectively. The NCUC issued an Order on Remand Accepting CCR Settlement and Affirming Previous Orders Setting Rates and Imposing Penalties in the 2017 rate cases on June 25, 2021. 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, 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 and will be finalized upon issuance of the bonds. A remote evidentiary hearing ended on January 29, 2021. In the NCUC Orders in the 2019 rate cases issued on March 31, 2021, and April 16, 2021, for Duke Energy Carolinas and Duke Energy Progress, respectively, the reasonableness and prudence of the deferred storm costs was approved. On May 10, 2021, the NCUC issued financing orders authorizing the companies to issue storm recovery bonds, subject to the terms of the financing orders, and approving the Agreement and Stipulation of Partial Settlement in its entirety. Duke Energy Carolinas and Duke Energy Progress are currently in the process of structuring and marketing the bonds that will be presented to the market. Duke Energy Carolinas and Duke Energy Progress cannot predict the outcome of this matter. COVID-19 Filings North Carolina 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 the cost of 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. A summary of incremental COVID-19 costs incurred as of June 30, 2021, was filed with the NCUC by Duke Energy Carolinas and Duke Energy Progress on August 6, 2021. Duke Energy Carolinas and Duke Energy Progress cannot predict the outcome of this matter. South Carolina 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. Duke Energy Carolinas and Duke Energy Progress withdrew their joint petition on May 17, 2021. Duke Energy Carolinas 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 an ROE 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. 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, 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. 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, and approved by the NCUC on March 31, 2021. The NCUC issued an Order on Remand Accepting CCR Settlement and Affirming Previous Orders Setting Rates and Imposing Penalties on June 25, 2021. 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. On March 25, 2020, Duke Energy Carolinas and the Public Staff filed an Agreement and Stipulation of Partial Settlement, subject to review and approval of the NCUC, resolving certain issues in the base rate proceeding. On July 24, 2020, Duke Energy Carolinas filed its request for approval of its notice to customers required to implement temporary rates. On July 27, 2020, Duke Energy Carolinas filed a joint motion with Duke Energy Progress and the Public Staff notifying the commission that the parties reached a joint partial settlement with the Public Staff. Also on July 27, 2020, Duke Energy Carolinas filed a letter stating that it intended to update its temporary rates calculation to reflect the terms of the partial settlement. On July 31, 2020, Duke Energy Carolinas and the Public Staff filed a Second Agreement and Stipulation of Partial Settlement (Second Partial Settlement), subject to review and approval of the NCUC, resolving certain remaining issues in the base rate proceeding. The remaining items litigated at hearing included recovery of deferred coal ash compliance costs that are subject to asset retirement obligation accounting, implementation of new depreciation rates and the amortization period of the loss on the hydro station sale. On August 4, 2020, Duke Energy Carolinas filed an amended motion for approval of its amended notice to customers, seeking to exercise its statutory right to implement temporary rates subject to refund on or after August 24, 2020. The revenue requirement to be recovered, subject to refund, through the temporary rates was based on and consistent with the base rate component of the Second Partial Settlement and excluded the items to be litigated noted above. The NCUC approved the August 4, 2020 amended temporary rates motion on August 6, 2020, and temporary rates went into effect on August 24, 2020. The Duke Energy Carolinas evidentiary hearing concluded on September 18, 2020, and post-hearing filings were made with the NCUC from all parties by November 4, 2020. 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. On March 31, 2021, the NCUC issued an order approving the March 25, 2020, and July 31, 2020, partial settlements. The order includes approval of 1) an ROE of 9.6% based upon a capital structure of 52% equity and 48% debt; 2) deferral treatment of approximately $800 million of grid improvement projects with a return; 3) a flow back period of five years for unprotected federal EDIT; and 4) the reasonableness and prudence of $213 million of deferred storm costs, which were removed from the rate case and for which Duke Energy Carolinas filed a petition seeking securitization in October 2020. Additionally, the order approved without modification the CCR Settlement Agreement. The order denied Duke Energy Carolinas' proposal to shorten the remaining depreciable lives of certain Duke Energy Carolinas coal-fired generating units, indicating the NCUC has not had the chance to fully examine the issue within the context of an integrated resource planning (IRP) proceeding, and upon retirement the remaining net book value of these units should be placed in a regulatory asset account to be amortized over an appropriate period to be determined in a future rate case. On May 21, 2021, the NCUC issued an Order Approving Rate Schedules, which resulted in a net increase of approximately $33 million. Revised customer rates became effective on June 1, 2021. The deadline to appeal has passed and no parties appealed the NCUC's order. 2018 South Carolina Rate Case On November 8, 2018, Duke Energy Carolinas filed an application with the PSCSC for a rate increase for retail customers of approximately $168 million. After hearings in March 2019, the PSCSC issued an order on May 21, 2019, which included an ROE of 9.5% and a capital structure of 53% equity and 47% debt. The order also included the following material components: • Approval of cancellation of the Lee Nuclear Project, with Duke Energy Carolinas maintaining the Combined Operating License; • Approval of recovery of $125 million (South Carolina retail portion) of Lee Nuclear Project development costs (including AFUDC through December 2017) over a 12-year period, but denial of a return on the deferred balance of costs; • Approval of recovery of $96 million of coal ash costs over a five-year period with a return at Duke Energy Carolinas' WACC; • Denial of recovery of $115 million of certain coal ash costs deemed to be related to the Coal Ash Act and incremental to the federal CCR rule; • Approval of a $66 million decrease to base rates to reflect the change in ongoing tax expense, primarily the reduction in the federal income tax rate from 35% to 21%; • Approval of a $45 million decrease through the EDIT Rider to return EDIT resulting from the federal tax rate change and deferred revenues since January 2018 related to the change, to be returned in accordance with the Average Rate Assumption Method (ARAM) for protected EDIT, over a 20-year period for unprotected EDIT associated with Property, Plant and Equipment, over a five-year period for unprotected EDIT not associated with Property, Plant and Equipment and over a five-year period for the deferred revenues; and • Approval of a $17 million decrease through the EDIT Rider related to reductions in the North Carolina state income tax rate from 6.9% to 2.5% to be returned over a five-year period. As a result of the order, revised customer rates were effective June 1, 2019. On May 31, 2019, Duke Energy Carolinas filed a Petition for Rehearing or Reconsideration of that order contending substantial rights of Duke Energy Carolinas were prejudiced by unlawful, arbitrary and capricious rulings by the PSCSC on certain issues presented in the proceeding. On June 19, 2019, the PSCSC issued a Directive denying Duke Energy Carolinas' request to rehear or reconsider the commission's rulings on certain issues presented in the proceeding including coal ash remediation and disposal costs, ROE and the recovery of a return on deferred operation and maintenance expenses. An order detailing the commission's decision in the Directive was issued on October 18, 2019. Duke Energy Carolinas filed a notice of appeal on November 15, 2019, with the Supreme Court of South Carolina. On November 20, 2019, the South Carolina Energy Users Committee filed a Notice of Appeal with the Supreme Court of South Carolina. Initial briefs were filed on April 21, 2020, which included the South Carolina Energy User's Committee brief arguing that the PSCSC erred in allowing Duke Energy Carolinas' recovery of costs related to the Lee Nuclear Station. Response briefs were filed on July 6, 2020, and reply briefs were filed on August 11, 2020. Oral arguments were heard before the Supreme Court of South Carolina on May 26, 2021. On October 27, 2021, the Supreme Court of South Carolina affirmed the PSCSC's May 2019 order to: • Disallow cost recovery on certain CCR compliance costs the PSCSC deemed to be incremental to the federal CCR rules; • Disallow recovery of certain coal ash litigation expenses; • Disallow a return on certain deferred expenses; and • Allow recovery of Lee Nuclear Project preconstruction costs. The Supreme Court's decision notes the prior determination made by the PSCSC that Duke Energy could submit coal ash costs for recovery that were not initially approved in the rate case order if such costs can be attributed to the CCR rules. As a result of the Court's opinion, Duke Energy Carolinas recognized a pretax charge of approximately $160 million to Impairment of assets and other charges, and a $31 million increase in Other income and expenses, net, in the Condensed Consolidated Statement of Operations for the three and nine months ended September 30, 2021, principally related to coal ash remediation at retired coal ash basin sites. Duke Energy Carolinas is evaluating whether to file a Petition for rehearing on the Supreme Court's decision. Petitions are due November 11, 2021, unless an extension is sought and granted. Oconee Nuclear Station Subsequent License Renewal On June 7, 2021, Duke Energy Carolinas filed a subsequent license renewal application for the Oconee Nuclear Station (ONS) with the U.S. Nuclear Regulatory Commission (NRC) to renew ONS’s operating license for an additional 20 years. The subsequent license renewal would extend operations of the facility from 60 to 80 years. The current license for units 1 and 2 expire in 2033 and the license for unit 3 expires in 2034. By a Federal Register Notice dated July 28, 2021, the NRC provided a 60-day comment period for persons whose interest may be affected by the issuance of a subsequent renewed license for ONS to file a request for a hearing and a petition for leave to intervene. On September 27, 2021, Beyond Nuclear and Sierra Club (Petitioners) filed a Hearing Request and Petition to Intervene (Hearing Request) and a Petition for Waiver. The Hearing Request proposes three contentions purporting to challenge Duke Energy Carolinas’ environmental report (ER). In general, the proposed contentions claim that the ER does not consider certain information regarding the environmental aspects of Severe Accidents caused by a hypothetical failure of the Jocassee Dam, and therefore does not satisfy the National Environmental Policy Act of 1969, as amended (NEPA), or the NRC’s NEPA-implementing regulations. Duke Energy Carolinas filed its answer to the proposed contentions on October 22, 2021, and the Petitioners have until November 5, 2021, to respond to Duke Energy Carolina’s answer. Duke Energy Carolinas and Duke Energy Progress intend to seek renewal of operating licenses and 20-year license extensions for all of their nuclear stations. New depreciation rates were implemented for all of the nuclear facilities during the second quarter of 2021. Duke Energy Carolinas and Duke Energy Progress cannot predict the outcome of this matter. Duke Energy Progress 2017 North Carolina Rate Case On June 1, 2017, Duke Energy Progress filed an application with the NCUC for a rate increase for retail customers of approximately $477 million, which was subsequently adjusted to $420 million. On November 22, 2017, Duke Energy Progress and the Public Staff filed an Agreement and Stipulation of Partial Settlement resolving certain portions of the proceeding. Terms of the settlement included an ROE of 9.9% and a capital structure of 52% equity and 48% debt. On February 23, 2018, the NCUC issued an order approving the stipulation. The Public Staff, the North Carolina Attorney General and the Sierra Club 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, 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. On January 22, 2021, Duke Energy Progress and Duke Energy Carolinas entered into the CCR Settlement Agreement with the Settling Parties, which was filed with the NCUC on January 25, 2021, and approved by the NCUC on April 16, 2021. The NCUC issued an Order on Remand Accepting CCR Settlement and Affirming Previous Orders Setting Rates and Imposing Penalties on June 25, 2021. 2019 North Carolina Rate Case On October 30, 2019, Duke Energy Progress filed an application with the NCUC for a net rate increase for retail customers of approximately $464 million, which represented an approximate 12.3% increase in annual base revenues. The gross rate case revenue increase request was $586 million, which was offset by riders of $122 million, primarily an EDIT rider of $120 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 Progress sought to defer and recover incremental Hurricane Dorian storm costs in this proceeding and requested rates be effective no later than September 1, 2020. As a result of the COVID-19 pandemic, on March 24, 2020, the NCUC suspended the procedural schedule and postponed the previously scheduled evidentiary hearing on this matter indefinitely. On June 2, 2020, Duke Energy Progress and the Public Staff filed an Agreement and Stipulation of Partial Settlement, subject to review and approval of the NCUC, resolving certain issues in the base rate proceeding. On July 27, 2020, Duke Energy Progress filed a joint motion with Duke Energy Carolinas and the Public Staff notifying the commission that the parties reached a joint partial settlement with the Public Staff. On July 31, 2020, Duke Energy Progress and the Public Staff filed a Second Agreement and Stipulation of Partial Settlement, subject to review and approval of the NCUC, resolving certain remaining issues in the base rate proceeding. The remaining items litigated at hearing included recovery of deferred coal ash compliance costs that are subject to asset retirement obligation accounting and implementation of new depreciation rates. On August 7, 2020, Duke Energy Progress filed a motion for approval of notice required to implement temporary rates, seeking to exercise its statutory right to implement temporary rates subject to refund on or after September 1, 2020. The revenue requirement to be recovered subject to refund through the temporary rates was based on and consistent with the terms of the base rate component of the settlement agreements with the Public Staff and excluded items to be litigated noted above. In addition, Duke Energy Progress also sought authorization to place a temporary decrement EDIT Rider into effect, concurrent with the temporary base rate change. The NCUC approved the August 7, 2020 temporary rates motion on August 11, 2020, and temporary rates went into effect on September 1, 2020. The Duke Energy Progress evidentiary hearing concluded on October 6, 2020, and post-hearing filings were filed with the NCUC from all parties by December 4, 2020. On January 22, 2021, Duke Energy Progress and Duke Energy Carolinas entered into the CCR Settlement Agreement with the Settling Parties, which was filed with the NCUC on January 25, 2021. On April 16, 2021, the NCUC issued an order approving the June 2, 2020, and July 31, 2020, partial settlements. The order includes approval of 1) an ROE of 9.6% based upon a capital structure of 52% equity and 48% debt; 2) deferral treatment of approximately $400 million of grid improvement projects with a return; 3) a flow back period of five years for unprotected federal EDIT; and 4) the reasonableness and prudence of approximately $714 million of deferred storm costs, which were removed from the rate case and for which Duke Energy Progress filed a petition seeking securitization in October 2020. Additionally, the order approved without modification the CCR Settlement Agreement. The order denied Duke Energy Progress' proposal to shorten the remaining depreciable lives of certain Duke Energy Progress coal-fired generating units, indicating the NCUC has not had the chance to fully examine the issue within the context of an IRP proceeding, and upon retirement the remaining net book value of these units should be placed in a regulatory asset account to be amortized over an appropriate period to be determined in a future rate case. On May 21, 2021, the NCUC issued an Order Approving Rate Schedules, which resulted in a net increase of approximately $178 million. Revised customer rates became effective on June 1, 2021. The deadline to appeal has passed and no parties appealed the NCUC's order. 2018 South Carolina Rate Case On November 8, 2018, Duke Energy Progress filed an application with the PSCSC for a rate increase for retail customers of approximately $59 million. After hearings in April 2019, the PSCSC issued an order on May 21, 2019, which included an ROE of 9.5% and a capital structure of 53% equity and 47% debt. The order also included the following material components: • Approval of recovery of $4 million of coal ash costs over a five-year period with a return at Duke Energy Progress' WACC; • Denial of recovery of $65 million of certain coal ash costs deemed to be related to the Coal Ash Act and incremental to the federal CCR rule; • Approval of a $17 million decrease to base rates to reflect the change in ongoing tax expense, primarily the reduction in the federal income tax rate from 35% to 21%; • Approval of a $12 million decrease through the EDIT Tax Savings Rider resulting from the federal tax rate change and deferred revenues since January 2018 related to the change, to be returned in accordance with ARAM for protected EDIT, over a 20-year period for unprotected EDIT associated with Property, Plant and Equipment, over a five-year period for unprotected EDIT not associated with Property, Plant and Equipment and over a three-year period for the deferred revenues; and • Approval of a $12 million increase due to the expiration of EDIT related to reductions in the North Carolina state income tax rate from 6.9% to 2.5%. As a result of the order, revised customer rates were effective June 1, 2019. On May 31, 2019, Duke Energy Progress filed a Petition for Rehearing or Reconsideration of that order contending substantial rights of Duke Energy Progress were prejudiced by unlawful, arbitrary and capricious rulings by the PSCSC on certain issues presented in the proceeding. On June 19, 2019, the PSCSC issued a Directive denying Duke Energy Progress' request to rehear or reconsider the commission's rulings on certain issues presented in the proceeding including coal ash remediation and disposal costs, ROE and the recovery of a return on deferred operation and maintenance expenses, but allowing additional litigation-related costs. As a result of the Directive allowing litigation-related costs, customer rates were revised effective July 1, 2019. An order detailing the commission's decision in the Directive was issued on October 18, 2019. Duke Energy Progress filed a notice of appeal on November 15, 2019, with the Supreme Court of South Carolina. Initial briefs were filed on April 21, 2020. Response briefs were filed on July 6, 2020, and reply briefs were filed on August 11, 2020. Oral arguments were heard before the Supreme Court of South Carolina on May 26, 2021. On October 27, 2021, the Supreme Court of South Carolina affirmed the PSCSC's May 2019 order to: • Disallow cost recovery on certain CCR compliance costs the PSCSC deemed to be incremental to the federal CCR rules; • Disallow recovery of certain coal ash litigation expenses; and • Disallow a return on certain deferred expenses. The Supreme Court's decision notes the prior determination made by the PSCSC that Duke Energy could submit coal ash costs for recovery that were not initially approved in the rate case order if such costs can be attributed to the CCR rules. As a result of the Court's opinion, Duke Energy Progress recognized a pretax charge of approximately $42 million to Impairment of assets and other charges, and a $6 million increase in Other income and expenses, net, in the Condensed Consolidated Statement of Operations for the three and nine months ended September 30, 2021, principally related to coal ash remediation at retired coal ash basin sites. Duke Energy Progress is evaluating whether to file a Petition for rehearing on the Supreme Court's decision. Petitions are due November 11, 2021, unless an extension is sought and granted. Western Carolinas Modernization Plan On October 8, 2018, Duke Energy Progress filed an application with the NCUC for a CPCN to construct the Hot Springs Microgrid Solar and Battery Storage Facility, which was approved with certain conditions on May 10, 2019. A hearing to update the NCUC on the status of the project was held on March 5, 2020. Construction began in May 2020 with commercial operation expected to begin in December 2021. On July 27, 2020, Duke Energy Progress filed an application with the NCUC for a CPCN to construct the Woodfin Solar Facility, a 5-MW solar generating facility to be constructed on a closed landfill in Buncombe County. The expert hearing was held on November 18, 2020. The application was approved and a CPCN was granted by order of the NCUC on April 20, 2021. Construction began in April 2021 with an expected in-service date in March 2022. FERC Return on Equity Complaints On October 11, 2019, North Carolina Eastern Municipal Power Agency (NCEMPA) filed a complaint at the FERC against Duke Energy Progress pursuant to Section 206 of the Federal Power Act (FPA), alleging that the 11% stated ROE component contained in the demand formula rate in the Full Requirements Power Purchase Agreement (FRPPA) between NCEMPA and Duke Energy Progress is unjust and unreasonable. On July 16, 2020, the FERC set this matter for hearing and settlement judge procedures and established a refund effective date of October 11, 2019. In its order setting the matter for settlement, the FERC allowed for the consideration of variations to the base transmission-related ROE methodology developed in its Order No. 569-A, through the introduction of “specific facts and circumstances” involving issues specific to the case. The parties reached a settlement in principle at a settlement conference on January 7, 2021, and filed a settlement package on March 10, 2021. The FERC Trial Staff filed comments in support of the settlement. On April 19, 2021, the Settlement Judge certified the settlemen

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments And Contingencies	COMMITMENTS AND CONTINGENCIES ENVIRONMENTAL The Duke Energy Registrants are subject to federal, state and local regulations regarding air and water quality, hazardous and solid waste disposal, coal ash and other environmental matters. These regulations can be changed from time to time, imposing new obligations on the Duke Energy Registrants. The following environmental matters impact all Duke Energy Registrants. Remediation Activities In addition to AROs recorded as a result of various environmental regulations, 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 on the Condensed Consolidated Statements of Operations unless regulatory recovery of the costs is deemed probable. The following table contains 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 Condensed Consolidated Balance Sheets. (in millions) September 30, 2021 December 31, 2020 Reserves for Environmental Remediation Duke Energy $ 74 $ 75 Duke Energy Carolinas 19 19 Progress Energy 17 19 Duke Energy Progress 6 6 Duke Energy Florida 11 12 Duke Energy Ohio 21 22 Duke Energy Indiana 5 6 Piedmont 12 10 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. LITIGATION D uke Energy Texas Storm Uri Tort Litigation Duke Energy and several Duke Energy renewables project companies have been named in multiple lawsuits arising out of Texas Storm Uri in mid-February 2021, and particularly, in the deregulated market managed by the Electric Reliability Council of Texas. There are 30 state court actions pending. These lawsuits seek recovery for property damages, personal injury and for wrongful death allegedly incurred by the plaintiffs as a result of power outages, which the plaintiffs claim was the result of the defendants' failures. The cases pending in state court have been consolidated into a Texas state court multidistrict litigation proceeding before a single judge to handle all pretrial coordination. Duke Energy cannot predict the outcomes of these matters. 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 U.S. Environmental Protection Agency CCR rule at 15 coal-fired plants in North Carolina and South Carolina. Duke Energy Carolinas and Duke Energy Progress have resolved claims against all, but two of the insurers, sued in this litigation and are dismissing their claims against the settling insurers. Duke Energy Carolinas and Duke Energy Progress have received approximately $418 million of coa l ash insurance litigation proceeds from settlements with insurer-defendants and these proceeds will be distributed in accordance with the terms of the CCR settlement agreement. The companies are assessing their options with regard to the two remaining foreign insurers that have defaulted. Duke Energy Carolinas and Duke Energy Progress cannot predict the outcome of this matter. Duke Energy Carolinas Ruben Villano, et al. v. Duke Energy Carolinas, LLC On June 16, 2021, a group of nine individuals went over a low head dam adjacent to the Dan River Steam Station in Eden, North Carolina, while water tubing. Emergency personnel rescued four people and five others were confirmed deceased. On August 11, 2021, Duke Energy Carolinas was served with the complaint filed in Durham County Superior Court on behalf of four survivors, which was later amended to include all the decedents along with the survivors. The lawsuit alleges that Duke Energy Carolinas knew that the river was used for recreational purposes and that Duke Energy did not adequately warn about the dam. On September 30, 2021, Duke Energy Carolinas filed its Motion to Dismiss and Motion for Transfer of Venue from Durham County to Rockingham County. A hearing on these motions is set for November 15, 2021, and discovery has commenced. Duke Energy Carolinas cannot predict the outcome of this matter. 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, 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 Carolinas' termination of the LGIA, FERC issued a ruling that 1) it has exclusive jurisdiction to determine whether a transmission provider may terminate a LGIA; 2) FERC approval is required to terminate a conforming LGIA if objected to by the interconnection customer; and 3) Duke Energy may not announce the termination of a conforming LGIA unless FERC has approved the termination. FERC's Office of Enforcement also initiated an investigation of Duke Energy Carolinas into matters pertaining to the LGIA. Duke Energy Carolinas is cooperating with the Office of Enforcement but cannot predict the outcome of this investigation. 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 September 30, 2021, there were 74 asserted claims for non-malignant cases with cumulative relief sought of up to $15 million, and 58 asserted claims for malignant cases with cumulative relief sought of up to $21 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 Caroli nas has recognized asbestos-related reserves of $508 million at September 30, 2021, and $572 million at December 31, 2020. These reserves are classified in Other within Other Noncurrent Liabilities and Other within Current Liabilities on the Condensed Consolidated Balance Sheets. These reserves are based upon Duke Energy Carolinas' best estimate for current and future asbestos claims through 2041 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 2041 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-insured 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 $697 million in excess of the self-insured retention. Receivables for insurance recoveries were $644 million at September 30, 2021, and $704 million at December 31, 2020. These amounts are classified in Other within Other Noncurrent Assets and Receivables within Current Assets on the Condensed 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 based on adoption of the new standard is $15 million for Duke Energy and Duke Energy Carolinas as of September 30, 2021, and 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 now complete, and trial is anticipated to be scheduled in 2022. Duke Energy Progress and Duke Energy Florida cannot predict the outcome of this matter. 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. The final arbitration hearing occurred during the week of December 7, 202 0. An interim arbitral award was issued in March 2021, upholding Duke Energy Florida's positions on all issues and awarding the company termination costs. In May 2021, the final arbitral award was issued awarding Duke Energy Florida its claimed fees and costs. O n August 18, 2021, Duke Energy Florida filed a motion in Florida state court to confirm the arbitral award. Duke Energy Indiana Coal Ash Basin Closure Plan Appeal On January 27, 2020, Hoosier Environmental Council (HEC) filed a Petition for Administrative Review with the Indiana Office of Environmental Adjudication challenging the Indiana Department of Environmental Management’s (IDEM's) December 10, 2019, partial approval of Duke Energy Indiana’s ash pond closure plan. After hearing oral arguments in early April 2021 on Duke Energy Indiana's and HEC's competing Motions for Summary Judgment, on May 4, 2021, the administrative court rejected all of HEC’s claims and issued a ruling in favor of Duke Energy Indiana. On June 3, 2021, HEC filed an appeal in Superior Court to seek judicial review of the order . On June 25, 2021, Duke Energy Indiana filed its response to the Petition to Review. On August 30, 2021, HEC served Duke Energy Indiana with its Brief in Support of Petition for Judicial Review. On October 29, 2021, Duke Energy Indiana and IDEM filed their response briefs. HEC's Reply Brief is due on or before November 22, 2021. Oral argument will be heard in December 2021, in Marion County Superior Court. Du ke Energy Indiana cannot predict the outcome of this matter. 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. Reserves are classified on the Condensed Consolidated Balance Sheets in Other within Other Noncurrent Liabilities and Other within Current Liabilities. 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 Condensed Consolidated Balance Sheets and have uncapped maximum potential payments. However, the Duke Energy Registrants do not believe these guarantees will have a material effect on their results of operations, cash flows or financial position. In addition, the Duke Energy Registrants enter into various fixed-price, noncancelable commitments to purchase or sell power or natural gas, take-or-pay arrangements, transportation, or throughput agreements and other contracts that may or may not be recognized on their respective Condensed Consolidated Balance Sheets. Some of these arrangements may be recognized at fair value on their respective Condensed Consolidated Balance Sheets if such contracts meet the definition of a derivative and the NPNS exception does not apply. In most cases, the Duke Energy Registrants’ purchase obligation contracts contain provisions for price adjustments, minimum purchase levels and other financial commitments.

Debt and Credit Facilities

Debt and Credit Facilities	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Debt And Credit Facilities	DEBT AND CREDIT FACILITIES SUMMARY OF SIGNIFICANT DEBT ISSUANCES The following table summarizes significant debt issuances (in millions). Nine Months Ended September 30, 2021 Duke Duke Duke Maturity Interest Duke Energy Energy Energy Issuance Date Date Rate Energy (Parent) Carolinas Progress Piedmont Unsecured Debt March 2021 (a) March 2031 2.500 % $ 350 $ — $ — $ — $ 350 June 2021 (b)(c) June 2023 2.500 % 500 500 — — — June 2021 (c) June 2031 2.550 % 1,000 1,000 — — — June 2021 (c) June 2041 3.300 % 750 750 — — — June 2021 (c) June 2051 3.500 % 750 750 — — — September 2021 (d) January 2082 3.250 % 500 500 — — — First Mortgage Bonds April 2021 (e) April 2031 2.550 % 550 — 550 — — April 2021 (e) April 2051 3.450 % 450 — 450 — — August 2021 (f) August 2031 2.000 % 650 — — 650 — August 2021 (f) August 2051 2.900 % 450 — — 450 — Total issuances $ 5,950 $ 3,500 $ 1,000 $ 1,100 $ 350 (a) Debt issued to repay at maturity $160 million senior unsecured notes due June 2021, pay down short-term debt and for general corporate purposes. (b) Debt issuance has a floating interest rate. (c) Debt issued to repay $1.75 billion of Duke Energy (Parent) 2021 debt maturities, to repay a portion of short-term debt and for general corporate purposes. (d) Debt issued to repay in October 2021 $500 million of Duke Energy (Parent) unsecured notes. The interest rate resets every five years. (e) Debt issued to repay at maturity $500 million first mortgage bonds due June 2021, pay down short-term debt and for general company purposes. (f) Debt issued to repay at maturity a total of $600 million first mortgage bonds due September 2021, pay down short-term debt and for general company purposes. CURRENT MATURITIES OF LONG-TERM DEBT The following table shows the significant components of Current maturities of long-term debt on the Condensed 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 September 30, 2021 Unsecured Debt Duke Energy (Parent) (a) October 2021 5.125 % 500 Duke Energy Florida (b) November 2021 0.372 % 200 Duke Energy Progress (b) February 2022 0.305 % 700 Duke Energy (Parent) March 2022 3.227 % 300 Duke Energy (Parent) (b) March 2022 0.764 % 300 Progress Energy April 2022 3.150 % 450 Duke Energy (Parent) August 2022 3.050 % 500 Duke Energy (Parent) August 2022 2.400 % 500 First Mortgage Bonds Duke Energy Indiana January 2022 8.850 % 53 Duke Energy Carolinas May 2022 3.350 % 350 Duke Energy Progress May 2022 2.800 % 500 Other (c) 520 Current maturities of long-term debt $ 4,873 (a) Junior unsecured notes due January 2073 were redeemed on October 7, 2021. (b) Debt has a floating interest rate. (c) Includes finance lease obligations, amortizing debt, tax-exempt bonds with mandatory put options and small bullet maturities. AVAILABLE CREDIT FACILITIES Master Credit Facility In March 2021, Duke Energy amended its existing $8 billion Master Credit Facility to extend the termination date to March 2026. 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. September 30, 2021 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 $ 1,275 $ 1,150 $ 850 $ 775 $ 600 $ 700 Reduction to backstop issuances Commercial paper (b) (1,611) 389 (375) (253) (527) (419) (150) (276) Outstanding letters of credit (31) (25) (4) (2) — — — — Tax-exempt bonds (81) — — — — — (81) — Available capacity under the Master Credit Facility $ 6,277 $ 3,014 $ 896 $ 895 $ 323 $ 356 $ 369 $ 424 (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 on the Condensed Consolidated Balance Sheets. Other Credit Facilities September 30, 2021 (in millions) Facility size Amount drawn Duke Energy (Parent) Three (a) $ 1,000 $ 500 (a) During March 2021, Duke Energy extended the maturity date of the Three-Year Revolving Credit Facility from May 2022 to May 2024. Duke Energy Ohio Term Loan Facility In October 2021, Duke Energy Ohio entered into a two-year term loan facility with commitments totaling $100 million . Borrowings under the facility will be used to pay down short-term debt and for general corporate purposes. The term loan was fully drawn at the time of closing in October. The balance will be classified as Long-Term Debt on Duke Energy Ohio’s Condensed Consolidated Balance Sheets. Duke Energy Kentucky Term Loan Facility In October 2021, Duke Energy Kentucky entered into a two-year term loan facility with commitments totaling $50 million . Borrowings under the facility will be used to pay down short-term debt and for general corporate purposes. The term loan was fully drawn at the time of closing in October. The balance will be classified as Long-Term Debt on Duke Energy Ohio's Condensed Consolidated Balance Sheet. Duke Energy Indiana Term Loan Facility In October 2021, Duke Energy Indiana entered into a two-year term loan facility with commitments totaling $300 million. Borrowings under the facility will be used to pay down short-term debt and for general corporate purposes. The term loan was fully drawn at the time of closing in October. The balance will be classified as Long-Term Debt on Duke Energy Indiana’s Condensed Consolidated Balance Sheet.

Goodwill

Goodwill	9 Months Ended
	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	GOODWILL Duke Energy The following table presents the goodwill by reportable segment included on Duke Energy's Condensed Consolidated Balance Sheets at September 30, 2021, and December 31, 2020. Electric Utilities Gas Utilities Commercial (in millions) and Infrastructure and Infrastructure Renewables Total Goodwill balance $ 17,379 $ 1,924 $ 122 $ 19,425 Accumulated impairment charges — — (122) (122) Goodwill, adjusted for accumulated impairment charges $ 17,379 $ 1,924 $ — $ 19,303 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 Condensed Consolidated Balance Sheets at September 30, 2021, and December 31, 2020. 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. 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 the third quarter of 2021.

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2021
Related Party Transactions [Abstract]
Related Party Transactions	RELATED PARTY TRANSACTIONS The Subsidiary Registrants engage in related party transactions in accordance with applicable state and federal commission regulations. Refer to the Condensed 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 on the Condensed Consolidated Statements of Operations and Comprehensive Income are presented in the following table. Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2021 2020 2021 2020 Duke Energy Carolinas Corporate governance and shared service expenses (a) $ 207 $ 198 $ 653 $ 528 Indemnification coverages (b) 6 5 18 15 Joint Dispatch Agreement (JDA) revenue (c) 6 6 32 16 JDA expense (c) 68 28 133 72 Intercompany natural gas purchases (d) 14 10 43 26 Progress Energy Corporate governance and shared service expenses (a) $ 201 $ 185 $ 615 $ 520 Indemnification coverages (b) 10 9 31 27 JDA revenue (c) 68 28 133 72 JDA expense (c) 6 6 32 16 Intercompany natural gas purchases (d) 19 18 56 56 Duke Energy Progress Corporate governance and shared service expenses (a) $ 121 $ 113 $ 367 $ 301 Indemnification coverages (b) 4 4 14 13 JDA revenue (c) 68 28 133 72 JDA expense (c) 6 6 32 16 Intercompany natural gas purchases (d) 19 18 56 56 Duke Energy Florida Corporate governance and shared service expenses (a) $ 80 $ 72 $ 248 $ 219 Indemnification coverages (b) 6 5 17 14 Duke Energy Ohio Corporate governance and shared service expenses (a) $ 79 $ 80 $ 237 $ 241 Indemnification coverages (b) 1 1 3 3 Duke Energy Indiana Corporate governance and shared service expenses (a) $ 96 $ 102 $ 302 $ 300 Indemnification coverages (b) 2 2 6 6 Piedmont Corporate governance and shared service expenses (a) $ 32 $ 31 $ 101 $ 102 Indemnification coverages (b) 1 1 3 2 Intercompany natural gas sales (d) 33 28 99 82 Natural gas storage and transportation costs (e) 6 6 17 17 (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 and Impairment of assets and other charges on the Condensed 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 Condensed 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 Condensed 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 Condensed Consolidated Statements of Operations and Comprehensive Income. (e) Piedmont has related party transactions as a customer of its equity method investments in Pine Needle LNG Company, LLC, Hardy Storage Company, LLC and Cardinal Pipeline Company, LLC natural gas storage and transportation facilities. These expenses are included in Cost of natural gas on Piedmont's Condensed 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, such as pipeline lease arrangements, and their proportionate share of certain charged expenses. These transactions of the Subsidiary Registrants are incurred in the ordinary course of business and are eliminated in consolidation. As discussed in Note 11, 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 September 30, 2021 Intercompany income tax receivable $ — $ 36 $ — $ 8 $ 1 $ — $ 14 Intercompany income tax payable 133 — 51 — — 17 — December 31, 2020 Intercompany income tax receivable $ — $ — $ — $ — $ — $ 9 $ 10 Intercompany income tax payable 31 33 46 35 2 — —

Derivatives and Hedging

Derivatives and Hedging	9 Months Ended
	Sep. 30, 2021
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 Condensed Consolidated Balance Sheets. Cash collateral related to derivative instruments executed under master netting arrangements is offset against the collateralized derivatives on the Condensed Consolidated Balance Sheets. The cash impacts of settled derivatives are recorded as operating activities on the Condensed 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 accumulated other comprehensive loss for the three and nine months ended September 30, 2021, and 2020, 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 Condensed Consolidated Statements of Operations and Comprehensive Income. The following table shows notional amounts of outstanding derivatives related to interest rate risk. September 30, 2021 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Cash flow hedges $ 2,094 $ — $ — $ — $ — $ — Undesignated contracts 1,371 350 900 400 500 27 Total notional amount (a) $ 3,465 $ 350 $ 900 $ 400 $ 500 $ 27 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 (a) Duke Energy includes amounts related to consolidated VIEs of $594 million in cash flow hedges and $94 million in undesignated contracts as of September 30, 2021, and $632 million in cash flow hedges as of December 31, 2020. 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 loss for the three and nine months ended September 30, 2021, and 2020, were 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 natural gas costs 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. September 30, 2021 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy Carolinas Energy Progress Ohio Indiana Piedmont Electricity (GWh) (a) 29,044 — — — 3,004 15,881 — Natural gas (millions of dekatherms) 772 230 190 190 — 7 345 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 dekatherms) 678 145 158 158 — 2 373 (a) Duke Energy includes 10,159 GWh and 22,048 GWh related to cash flow hedges as of September 30, 2021, and December 31, 2020, respectively. LOCATION AND FAIR VALUE OF DERIVATIVE ASSETS AND LIABILITIES RECOGNIZED ON THE CONDENSED 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 Condensed 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 September 30, 2021 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 $ 359 $ 171 $ 135 $ 135 $ — $ 4 $ 36 $ 12 Noncurrent 177 100 78 78 — — — — Total Derivative Assets – Commodity Contracts $ 536 $ 271 $ 213 $ 213 $ — $ 4 $ 36 $ 12 Interest Rate Contracts Designated as Hedging Instruments Current $ 2 $ — $ — $ — $ — $ — $ — $ — Noncurrent 3 — — — — — — — Not Designated as Hedging Instruments Current $ 2 $ — $ 2 $ 2 $ — $ — $ — $ — Total Derivative Assets – Interest Rate Contracts $ 7 $ — $ 2 $ 2 $ — $ — $ — $ — Total Derivative Assets $ 543 $ 271 $ 215 $ 215 $ — $ 4 $ 36 $ 12 Derivative Liabilities September 30, 2021 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 $ 37 $ — $ — $ — $ — $ — $ — — Noncurrent 120 — — — — — — — Not Designated as Hedging Instruments Current $ 33 $ 12 $ — $ — $ — $ — $ 2 $ 20 Noncurrent 128 — — — — — — 128 Total Derivative Liabilities – Commodity Contracts $ 318 $ 12 $ — $ — $ — $ — $ 2 $ 148 Interest Rate Contracts Designated as Hedging Instruments Current $ 45 $ — $ — $ — $ — $ — $ — $ — Noncurrent 29 — — — — — — — Not Designated as Hedging Instruments Current 19 6 12 — 12 1 — — Noncurrent 4 — — — — 4 — — Total Derivative Liabilities – Interest Rate Contracts $ 97 $ 6 $ 12 $ — $ 12 $ 5 $ — $ — Total Derivative Liabilities $ 415 $ 18 $ 12 $ — $ 12 $ 5 $ 2 $ 148 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 OFFSETTING ASSETS AND LIABILITIES The following tables present the line items on the Condensed 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 September 30, 2021 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 $ 363 $ 171 $ 137 $ 137 $ — $ 4 $ 36 $ 12 Gross amounts offset (143) (87) (56) (56) — — — — Net amounts presented in Current Assets: Other $ 220 $ 84 $ 81 $ 81 $ — $ 4 $ 36 $ 12 Noncurrent Gross amounts recognized $ 180 $ 100 $ 78 $ 78 $ — $ — $ — $ — Gross amounts offset (71) (45) (26) (26) — — — — Net amounts presented in Other Noncurrent Assets: Other $ 109 $ 55 $ 52 $ 52 $ — $ — $ — $ — Derivative Liabilities September 30, 2021 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 $ 134 $ 18 $ 12 $ — $ 12 $ 1 $ 2 $ 20 Gross amounts offset — — — — — — — — Net amounts presented in Current Liabilities: Other $ 134 $ 18 $ 12 $ — $ 12 $ 1 $ 2 $ 20 Noncurrent Gross amounts recognized $ 281 $ — $ — $ — $ — $ 4 $ — $ 128 Gross amounts offset — — — — — — — — Net amounts presented in Other Noncurrent Liabilities: Other $ 281 $ — $ — $ — $ — $ 4 $ — $ 128 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

Investments in Debt and Equity

Investments in Debt and Equity Securities	9 Months Ended
	Sep. 30, 2021
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 fair value through net income (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 September 30, 2021, and December 31, 2020. Other Investments amounts are recorded in Other within Other Noncurrent Assets on the Condensed 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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value NDTF Cash and cash equivalents $ — $ — $ 164 $ — $ — $ 177 Equity securities 4,700 35 6,754 4,138 54 6,235 Corporate debt securities 44 5 847 76 1 806 Municipal bonds 13 1 296 22 — 370 U.S. government bonds 34 8 1,605 51 — 1,361 Other debt securities 4 1 195 8 — 180 Total NDTF Investments $ 4,795 $ 50 $ 9,861 $ 4,295 $ 55 $ 9,129 Other Investments Cash and cash equivalents $ — $ — $ 87 $ — $ — $ 127 Equity securities 83 — 145 79 — 146 Corporate debt securities 4 1 130 8 — 110 Municipal bonds 3 1 69 5 — 86 U.S. government bonds — — 50 — — 42 Other debt securities — — 34 — — 47 Total Other Investments $ 90 $ 2 $ 515 $ 92 $ — $ 558 Total Investments $ 4,885 $ 52 $ 10,376 $ 4,387 $ 55 $ 9,687 Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the three and nine months ended September 30, 2021, and 2020, were as follows. Three Months Ended Nine Months Ended (in millions) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 FV-NI: Realized gains $ 34 $ 13 $ 320 $ 338 Realized losses 40 16 100 148 AFS: Realized gains 17 26 51 73 Realized losses 15 19 46 38 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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value NDTF Cash and cash equivalents $ — $ — $ 60 $ — $ — $ 30 Equity securities 2,725 14 3,912 2,442 23 3,685 Corporate debt securities 27 3 495 49 1 510 Municipal bonds 1 — 24 6 — 91 U.S. government bonds 18 2 752 25 — 475 Other debt securities 4 1 190 7 — 174 Total NDTF Investments $ 2,775 $ 20 $ 5,433 $ 2,529 $ 24 $ 4,965 Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the three and nine months ended September 30, 2021, and 2020, were as follows. Three Months Ended Nine Months Ended (in millions) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 FV-NI: Realized gains $ 25 $ 10 $ 243 $ 46 Realized losses 29 12 68 82 AFS: Realized gains 10 20 35 50 Realized losses 10 17 32 30 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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value NDTF Cash and cash equivalents $ — $ — $ 104 $ — $ — $ 147 Equity securities 1,975 21 2,842 1,696 31 2,550 Corporate debt securities 17 2 352 27 — 296 Municipal bonds 12 1 272 16 — 279 U.S. government bonds 16 6 853 26 — 886 Other debt securities — — 5 1 — 6 Total NDTF Investments $ 2,020 $ 30 $ 4,428 $ 1,766 $ 31 $ 4,164 Other Investments Cash and cash equivalents $ — $ — $ 18 $ — $ — $ 106 Municipal bonds 2 — 26 3 — 26 Total Other Investments $ 2 $ — $ 44 $ 3 $ — $ 132 Total Investments $ 2,022 $ 30 $ 4,472 $ 1,769 $ 31 $ 4,296 Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the three and nine months ended September 30, 2021, and 2020, were as follows. Three Months Ended Nine Months Ended (in millions) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 FV-NI: Realized gains $ 9 $ 3 $ 77 $ 292 Realized losses 11 4 32 66 AFS: Realized gains 7 6 14 17 Realized losses 6 2 12 7 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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value NDTF Cash and cash equivalents $ — $ — $ 92 $ — $ — $ 76 Equity securities 1,882 21 2,736 1,617 31 2,459 Corporate debt securities 17 2 287 27 — 296 Municipal bonds 12 1 272 16 — 279 U.S. government bonds 16 2 466 26 — 412 Other debt securities — — 5 1 — 6 Total NDTF Investments $ 1,927 $ 26 $ 3,858 $ 1,687 $ 31 $ 3,528 Other Investments Cash and cash equivalents $ — $ — $ 16 $ — $ — $ 1 Total Other Investments $ — $ — $ 16 $ — $ — $ 1 Total Investments $ 1,927 $ 26 $ 3,874 $ 1,687 $ 31 $ 3,529 Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the three and nine months ended September 30, 2021, and 2020, were as follows. Three Months Ended Nine Months Ended (in millions) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 FV-NI: Realized gains $ 9 $ 3 $ 76 $ 43 Realized losses 11 4 31 51 AFS: Realized gains 6 6 13 17 Realized losses 5 2 11 7 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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value NDTF Cash and cash equivalents $ — $ — $ 12 $ — $ — $ 71 Equity securities 93 — 106 79 — 91 Corporate debt securities — — 65 — — — U.S. government bonds — 4 387 — — 474 Total NDTF Investments (a) $ 93 $ 4 $ 570 $ 79 $ — $ 636 Other Investments Cash and cash equivalents $ — $ — $ 1 $ — $ — $ 1 Municipal bonds 2 — 26 3 — 26 Total Other Investments $ 2 $ — $ 27 $ 3 $ — $ 27 Total Investments $ 95 $ 4 $ 597 $ 82 $ — $ 663 (a) During the nine months ended September 30, 2021, and the year ended December 31, 2020, Duke Energy Florida received reimbursements from the NDTF for costs related to ongoing decommissioning activity of Crystal River Unit 3. Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the three and nine months ended September 30, 2021, and 2020, were as follows: Three Months Ended Nine Months Ended (in millions) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 FV-NI: Realized gains $ — $ — $ 1 $ 249 Realized losses — — 1 15 AFS: Realized gains 1 — 1 — Realized losses 1 — 1 — 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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value Investments Cash and cash equivalents $ — $ — $ 19 $ — $ — $ 1 Equity securities 56 — 90 58 — 97 Corporate debt securities — — 5 — — 3 Municipal bonds 1 1 36 1 — 38 U.S. government bonds — — 5 — — 4 Total Investments $ 57 $ 1 $ 155 $ 59 $ — $ 143 Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the three and nine months ended September 30, 2021, and 2020, were immaterial. DEBT SECURITY MATURITIES The table below summarizes the maturity date for debt securities. September 30, 2021 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Indiana Due in one year or less $ 151 $ 3 $ 121 $ 22 $ 99 $ 5 Due after one through five years 954 343 548 244 304 18 Due after five through 10 years 639 268 286 247 39 8 Due after 10 years 1,482 847 553 517 36 15 Total $ 3,226 $ 1,461 $ 1,508 $ 1,030 $ 478 $ 46

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2021
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 (NAV) per share practical expedient. The NAV 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 New York Stock Exchange 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 in Duke Energy's Annual Report on Form 10-K for the year ended December 31, 2020, 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 Condensed Consolidated Balance Sheets. Derivative amounts in the tables below for all Duke Energy Registrants exclude cash collateral, which is disclosed in Note 8. See Note 9 for additional information related to investments by major security type for the Duke Energy Registrants. September 30, 2021 (in millions) Total Fair Value Level 1 Level 2 Level 3 Not Categorized NDTF cash and cash equivalents $ 164 $ 164 $ — $ — $ — NDTF equity securities 6,754 6,705 — — 49 NDTF debt securities 2,943 998 1,945 — — Other equity securities 145 145 — — — Other debt securities 283 45 238 — — Other cash and cash equivalents 87 87 — — — Derivative assets 543 27 490 26 — Total assets 10,919 8,171 2,673 26 49 Derivative liabilities (415) (2) (256) (157) — Net assets (liabilities) $ 10,504 $ 8,169 $ 2,417 $ (131) $ 49 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 The following tables provide reconciliations of beginning and ending balances of assets and liabilities measured at fair value using Level 3 measurements. Derivatives (net) Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2021 2020 2021 2020 Balance at beginning of period $ (131) $ (92) $ (77) $ (102) Total pretax realized or unrealized losses included in comprehensive income (11) (102) (86) (102) Purchases, sales, issuances and settlements: Purchases — — 21 14 Settlements 4 (3) (4) (18) Total gains (losses) included on the Condensed Consolidated Balance Sheet 7 (6) 15 5 Balance at end of period $ (131) $ (203) $ (131) $ (203) DUKE ENERGY CAROLINAS The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets. September 30, 2021 (in millions) Total Fair Value Level 1 Level 2 Not Categorized NDTF cash and cash equivalents $ 60 $ 60 $ — $ — NDTF equity securities 3,912 3,863 — 49 NDTF debt securities 1,461 359 1,102 — Derivative assets 271 — 271 — Total assets 5,704 4,282 1,373 49 Derivative liabilities (18) — (18) — Net assets $ 5,686 $ 4,282 $ 1,355 $ 49 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 PROGRESS ENERGY The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets. September 30, 2021 December 31, 2020 (in millions) Total Fair Value Level 1 Level 2 Total Fair Value Level 1 Level 2 NDTF cash and cash equivalents $ 104 $ 104 $ — $ 147 $ 147 $ — NDTF equity securities 2,842 2,842 — 2,550 2,550 — NDTF debt securities 1,482 639 843 1,467 682 785 Other debt securities 26 — 26 26 — 26 Other cash and cash equivalents 18 18 — 106 106 — Derivative assets 215 — 215 33 — 33 Total assets 4,687 3,603 1,084 4,329 3,485 844 Derivative liabilities (12) — (12) (29) — (29) Net assets $ 4,675 $ 3,603 $ 1,072 $ 4,300 $ 3,485 $ 815 DUKE ENERGY PROGRESS The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets. September 30, 2021 December 31, 2020 (in millions) Total Fair Value Level 1 Level 2 Total Fair Value Level 1 Level 2 NDTF cash and cash equivalents $ 92 $ 92 $ — $ 76 $ 76 $ — NDTF equity securities 2,736 2,736 — 2,459 2,459 — NDTF debt securities 1,030 278 752 993 237 756 Other cash and cash equivalents 16 16 — 1 1 — Derivative assets 215 — 215 33 — 33 Total assets 4,089 3,122 967 3,562 2,773 789 Derivative liabilities — — — (14) — (14) Net assets $ 4,089 $ 3,122 $ 967 $ 3,548 $ 2,773 $ 775 DUKE ENERGY FLORIDA The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets. September 30, 2021 December 31, 2020 (in millions) Total Fair Value Level 1 Level 2 Total Fair Value Level 1 Level 2 NDTF cash and cash equivalents $ 12 $ 12 $ — $ 71 $ 71 $ — NDTF equity securities 106 106 — 91 91 — NDTF debt securities 452 361 91 474 445 29 Other debt securities 26 — 26 26 — 26 Other cash and cash equivalents 1 1 — 1 1 — Total assets 597 480 117 663 608 55 Derivative liabilities (12) — (12) — — — Net assets $ 585 $ 480 $ 105 $ 663 $ 608 $ 55 DUKE ENERGY OHIO The recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets were not material at September 30, 2021, and December 31, 2020. DUKE ENERGY INDIANA The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets. September 30, 2021 December 31, 2020 (in millions) Total Fair Value Level 1 Level 2 Level 3 Total Fair Value Level 1 Level 2 Level 3 Other equity securities $ 90 $ 90 $ — $ — $ 97 $ 97 $ — $ — Other debt securities 46 — 46 — 45 — 45 — Other cash and cash equivalents 19 19 — — 1 1 — — Derivative assets 36 12 — 24 6 — — 6 Total assets 191 121 46 24 149 98 45 6 Derivative liabilities (2) (2) — — (1) (1) — — Net assets $ 189 $ 119 $ 46 $ 24 $ 148 $ 97 $ 45 $ 6 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) Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2021 2020 2021 2020 Balance at beginning of period $ 22 $ 10 $ 6 $ 11 Purchases, sales, issuances and settlements: Purchases — — 18 10 Settlements (3) (3) (12) (13) Total gains included on the Condensed Consolidated Balance Sheet 5 1 12 — Balance at end of period $ 24 $ 8 $ 24 $ 8 PIEDMONT The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets. September 30, 2021 December 31, 2020 (in millions) Total Fair Value Level 1 Level 2 Total Fair Value Level 1 Level 2 Derivative assets $ 12 $ 12 $ — $ 1 $ 1 $ — Derivative liabilities (148) — (148) (122) — (122) Net (liabilities) assets $ (136) $ 12 $ (148) $ (121) $ 1 $ (122) 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) Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2021 2020 2021 2020 Balance at beginning of period $ — $ (105) $ — $ (117) Total (losses) gains and settlements — (6) — 6 Balance at end of period $ — $ (111) $ — $ (111) QUANTITATIVE INFORMATION ABOUT UNOBSERVABLE INPUTS The following tables include quantitative information about the Duke Energy Registrants' derivatives classified as Level 3. September 30, 2021 Weighted Fair Value Average Investment Type (in millions) Valuation Technique Unobservable Input Range Range Duke Energy Electricity contracts $ (157) RTO forward pricing Forward electricity curves – price per MWh $ 18.02 - $ 143.85 $ 38.43 Duke Energy Ohio FTRs 2 RTO auction pricing FTR price – per MWh 0.06 - 1.27 0.71 Duke Energy Indiana FTRs 24 RTO auction pricing FTR price – per MWh (1.11) - 8.55 1.61 Duke Energy Total Level 3 derivatives $ (131) 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) 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. September 30, 2021 December 31, 2020 (in millions) Book Value Fair Value Book Value Fair Value Duke Energy (a) $ 62,802 $ 69,381 $ 59,863 $ 69,292 Duke Energy Carolinas 12,975 14,964 12,218 14,917 Progress Energy 19,488 22,593 19,264 23,470 Duke Energy Progress 9,848 10,915 9,258 10,862 Duke Energy Florida 7,549 8,932 7,915 9,756 Duke Energy Ohio 3,092 3,517 3,089 3,650 Duke Energy Indiana 4,092 4,883 4,091 5,204 Piedmont 2,968 3,320 2,780 3,306 (a) Book value of long-term debt inc ludes $1.3 billion at September 30, 2021, and December 31, 2020, of net unamortized debt discount and premium of purchase accounting adjustments related to the mergers with Progress Energy and Piedmont that are excluded from fair value of long-term debt.

Variable Interest Entities

Variable Interest Entities	9 Months Ended
	Sep. 30, 2021
Variable Interest Entities [Abstract]
Variable Interest Entities	VARIABLE INTEREST ENTITIES 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 nine months ended September 30, 2021, and the year ended December 31, 2020, 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 Condensed Consolidated Balance Sheets as Long-Term Debt. Amounts borrowed under the credit facilities for DEFR are reflected on the Condensed Consolidated Balance Sheets as Current maturities of long-term debt. 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 Condensed 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. 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 2023 Credit facility amount $ 350 $ 475 $ 350 $ 250 Amounts borrowed at September 30, 2021 350 475 350 250 Amounts borrowed at December 31, 2020 350 364 250 250 Restricted Receivables at September 30, 2021 535 915 532 443 Restricted Receivables at December 31, 2020 547 696 500 397 Nuclear Asset-Recovery Bonds – 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 Condensed Consolidated Balance Sheets. (in millions) September 30, 2021 December 31, 2020 Receivables of VIEs $ 6 $ 4 Regulatory Assets: Current 54 53 Current Assets: Other 17 39 Other Noncurrent Assets: Regulatory assets 896 937 Current Liabilities: Other 2 10 Current maturities of long-term debt 56 55 Long-Term Debt 946 1,002 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 Engineering, Procurement and Construction 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 Condensed Consolidated Balance Sheets related to Commercial Renewables VIEs. (in millions) September 30, 2021 December 31, 2020 Current Assets: Other $ 330 $ 257 Property, Plant and Equipment: Cost 7,315 6,394 Accumulated depreciation and amortization (1,414) (1,242) Other Noncurrent Assets: Other 110 67 Current maturities of long-term debt 165 167 Long-Term Debt 1,552 1,569 Other Noncurrent Liabilities: AROs 167 148 Other Noncurrent Liabilities: Other 341 316 NON-CONSOLIDATED VIEs The following tables summarize the impact of non-consolidated VIEs on the Condensed Consolidated Balance Sheets. September 30, 2021 Duke Energy Duke Duke Pipeline Commercial Energy Energy (in millions) Investments Renewables Total Ohio Indiana Receivables from affiliated companies $ — $ — $ — $ 47 $ 77 Investments in equity method unconsolidated affiliates 15 465 480 — — Deferred tax asset 58 — 58 — — Total assets $ 73 $ 465 $ 538 $ 47 $ 77 Other current liabilities 61 3 64 — — Other noncurrent liabilities 63 3 66 — — Total liabilities $ 124 $ 6 $ 130 $ — $ — Net (liabilities) assets $ (51) $ 459 $ 408 $ 47 $ 77 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 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 certain renewable energy project entities guarantees for debt services and operations and maintenance, 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. For the three and nine months ended September 30, 2020, the ACP investment was considered a significant subsidiary because its loss exceeded 10% of Duke Energy’s income. ACP's net loss for the three and nine months ended September 30, 2020, was $163 million and $4,505 million, respectively. In 2020, Duke Energy determined that it would no longer invest in the construction of the ACP pipeline. In February 2021, Duke Energy paid approximately $855 million to fund ACP's outstanding debt, relieving Duke Energy of its guarantee. See Notes 1 and 3 for further information regarding this transaction. Commercial Renewables Duke Energy has investments in various renewable energy project entities. Duke Energy has a 50% ownership in a VIE, which owns a portfolio of wind projects. This entity is a VIE as a result of Duke Energy issuing guarantees for debt service and operations and maintenance reserves in support of debt financings. Duke Energy does not consolidate this VIE because power to direct and control key activities is shared jointly by Duke Energy and the other owner. Duke Energy also has equity ownership in an entity, which owns a portfolio of fuel cell projects. Duke Energy does not consolidate the fuel cell portfolio as it does not have the power to direct the activities that most significantly impact the economic performance of the entity. 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. Duke Energy cannot predict the outcome in 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. The following table shows the gross and net receivables sold. Duke Energy Ohio Duke Energy Indiana (in millions) September 30, 2021 December 31, 2020 September 30, 2021 December 31, 2020 Receivables sold $ 218 $ 270 $ 328 $ 344 Less: Retained interests 47 83 77 110 Net receivables sold $ 171 $ 187 $ 251 $ 234 The following table shows sales and cash flows related to receivables sold. Duke Energy Ohio Duke Energy Indiana Three Months Ended Nine Months Ended Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, (in millions) 2021 2020 2021 2020 2021 2020 2021 2020 Sales Receivables sold $ 486 $ 462 $ 1,490 $ 1,428 $ 794 $ 717 $ 2,176 $ 1,947 Loss recognized on sale 2 2 7 8 4 3 10 9 Cash flows Cash proceeds from receivables sold $ 490 $ 449 $ 1,519 $ 1,439 $ 798 $ 689 $ 2,199 $ 1,941 Collection fees received — 1 1 1 — — 1 1 Return received on retained interests 1 1 3 3 1 1 4 4 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 Condensed Consolidated Statements of Cash Flows.

Revenue

Revenue	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Revenue	REVENUE 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. 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 $ 24 $ 107 $ 44 $ 45 $ 7 $ 51 $ 278 Duke Energy Progress 2 8 8 8 — — 26 Duke Energy Florida 22 99 36 37 7 51 252 Duke Energy Indiana — 1 9 14 15 25 64 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. 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 $ 17 $ 67 $ 64 $ 61 $ 60 $ 336 $ 605 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 Renewable Energy Certificates (RECs) to customers. Some of these PPAs have 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. Other The remainder of Duke Energy’s operations is presented as Other, which does not include material revenues from contracts with customers. Disaggregated Revenues Disaggregated revenues are presented as follows: Three Months Ended September 30, 2021 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 $ 2,955 $ 892 $ 1,525 $ 619 $ 906 $ 223 $ 316 $ — General 1,873 685 826 400 426 119 240 — Industrial 861 360 264 195 69 35 202 — Wholesale 619 111 399 324 75 19 89 — Other revenues 252 72 198 118 80 17 23 — Total Electric Utilities and Infrastructure revenue from contracts with customers $ 6,560 $ 2,120 $ 3,212 $ 1,656 $ 1,556 $ 413 $ 870 $ — Gas Utilities and Infrastructure Residential $ 129 $ — $ — $ — $ — $ 62 $ — $ 66 Commercial 78 — — — — 24 — 58 Industrial 30 — — — — 3 — 26 Power Generation — — — — — — — 23 Other revenues 33 — — — — 4 — 9 Total Gas Utilities and Infrastructure revenue from contracts with customers $ 270 $ — $ — $ — $ — $ 93 $ — $ 182 Commercial Renewables Revenue from contracts with customers $ 56 $ — $ — $ — $ — $ — $ — $ — Other Revenue from contracts with customers $ 8 $ — $ — $ — $ — $ — $ — $ — Total revenue from contracts with customers $ 6,894 $ 2,120 $ 3,212 $ 1,656 $ 1,556 $ 506 $ 870 $ 182 Other revenue sources (a) $ 57 $ (16) $ 21 $ 11 $ 5 $ — $ 16 $ 13 Total revenues $ 6,951 $ 2,104 $ 3,233 $ 1,667 $ 1,561 $ 506 $ 886 $ 195 (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. Three Months Ended September 30, 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 $ 2,936 $ 883 $ 1,550 $ 616 $ 934 $ 213 $ 289 $ — General 1,804 664 805 384 421 119 212 — Industrial 797 342 245 179 66 35 175 — Wholesale 603 117 412 358 54 10 64 — Other revenues 238 62 167 75 92 23 22 — Total Electric Utilities and Infrastructure revenue from contracts with customers $ 6,378 $ 2,068 $ 3,179 $ 1,612 $ 1,567 $ 400 $ 762 $ — Gas Utilities and Infrastructure Residential $ 112 $ — $ — $ — $ — $ 55 $ — $ 57 Commercial 64 — — — — 20 — 44 Industrial 24 — — — — 3 — 22 Power Generation — — — — — — — 10 Other revenues 16 — — — — 3 — 11 Total Gas Utilities and Infrastructure revenue from contracts with customers $ 216 $ — $ — $ — $ — $ 81 $ — $ 144 Commercial Renewables Revenue from contracts with customers $ 57 $ — $ — $ — $ — $ — $ — $ — Other Revenue from contracts with customers $ 7 $ — $ — $ — $ — $ — $ — $ — Total revenue from contracts with customers $ 6,658 $ 2,068 $ 3,179 $ 1,612 $ 1,567 $ 481 $ 762 $ 144 Other revenue sources (a) $ 63 $ (10) $ 18 $ 14 $ — $ (8) $ (1) $ 18 Total revenues $ 6,721 $ 2,058 $ 3,197 $ 1,626 $ 1,567 $ 473 $ 761 $ 162 (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. Nine Months Ended September 30, 2021 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 $ 7,753 $ 2,368 $ 3,903 $ 1,657 $ 2,246 $ 589 $ 894 $ — General 4,805 1,685 2,170 1,036 1,134 329 619 — Industrial 2,228 872 700 500 200 99 558 — Wholesale 1,644 341 1,056 901 155 45 202 — Other revenues 712 208 509 272 237 61 64 — Total Electric Utilities and Infrastructure revenue from contracts with customers $ 17,142 $ 5,474 $ 8,338 $ 4,366 $ 3,972 $ 1,123 $ 2,337 $ — Gas Utilities and Infrastructure Residential $ 747 $ — $ — $ — $ — $ 241 $ — $ 505 Commercial 373 — — — — 99 — 273 Industrial 110 — — — — 14 — 96 Power Generation — — — — — — — 69 Other revenues 100 — — — — 21 — 34 Total Gas Utilities and Infrastructure revenue from contracts with customers $ 1,330 $ — $ — $ — $ — $ 375 $ — $ 977 Commercial Renewables Revenue from contracts with customers $ 163 $ — $ — $ — $ — $ — $ — $ — Other Revenue from contracts with customers $ 20 $ — $ — $ — $ — $ — $ — $ — Total Revenue from contracts with customers $ 18,655 $ 5,474 $ 8,338 $ 4,366 $ 3,972 $ 1,498 $ 2,337 $ 977 Other revenue sources (a) $ 204 $ (44) $ 79 $ 51 $ 15 $ (4) $ 29 $ 39 Total revenues $ 18,859 $ 5,430 $ 8,417 $ 4,417 $ 3,987 $ 1,494 $ 2,366 $ 1,016 (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. Nine Months Ended September 30, 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 $ 7,451 $ 2,316 $ 3,792 $ 1,578 $ 2,214 $ 558 $ 785 $ — General 4,691 1,720 2,080 1,001 1,079 336 554 — Industrial 2,148 871 673 487 186 103 502 — Wholesale 1,535 332 1,018 877 141 22 163 — Other revenues 713 184 476 208 268 62 63 — Total Electric Utilities and Infrastructure revenue from contracts with customers $ 16,538 $ 5,423 $ 8,039 $ 4,151 $ 3,888 $ 1,081 $ 2,067 $ — Gas Utilities and Infrastructure Residential $ 631 $ — $ — $ — $ — $ 214 $ — $ 417 Commercial 308 — — — — 86 — 222 Industrial 92 — — — — 12 — 80 Power Generation — — — — — — — 27 Other revenues 58 — — — — 12 — 46 Total Gas Utilities and Infrastructure revenue from contracts with customers $ 1,089 $ — $ — $ — $ — $ 324 $ — $ 792 Commercial Renewables Revenue from contracts with customers $ 170 $ — $ — $ — $ — $ — $ — $ — Other Revenue from contracts with customers $ 20 $ — $ — $ — $ — $ — $ — $ — Total Revenue from contracts with customers $ 17,817 $ 5,423 $ 8,039 $ 4,151 $ 3,888 $ 1,405 $ 2,067 $ 792 Other revenue sources (a) $ 274 $ (7) $ 78 $ 56 $ 9 $ (11) $ 3 $ 79 Total revenues $ 18,091 $ 5,416 $ 8,117 $ 4,207 $ 3,897 $ 1,394 $ 2,070 $ 871 (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. Three Months Ended September 30, 2020 and 2021 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Balance at June 30, 2020 $ 102 $ 14 $ 29 $ 14 $ 14 $ 5 $ 3 $ 6 Write-Offs 12 (2) 15 13 2 — — — Credit Loss Expense (9) — (16) (15) — — — 3 Other Adjustments 28 10 9 9 — — — — Balance at September 30, 2020 $ 133 $ 22 $ 37 $ 21 $ 16 $ 5 $ 3 $ 9 Balance at June 30, 2021 $ 123 $ 42 $ 36 $ 21 $ 16 $ 4 $ 3 $ 13 Write-Offs (13) (3) (6) (3) (3) — — (4) Credit Loss Expense 11 4 6 3 3 — — 2 Other Adjustments 2 (1) — — — — — 4 Balance at September 30, 2021 $ 123 $ 42 $ 36 $ 21 $ 16 $ 4 $ 3 $ 15 Nine Months Ended September 30, 2020 and 2021 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 (7) (8) 8 8 — — — (5) Credit Loss Expense 24 9 2 (5) 8 1 — 7 Other Adjustments 35 10 9 9 — — — — Balance at September 30, 2020 $ 133 $ 22 $ 37 $ 21 $ 16 $ 5 $ 3 $ 9 Balance at December 31, 2020 $ 146 $ 23 $ 37 $ 23 $ 14 $ 4 $ 3 $ 12 Write-Offs (39) (10) (20) (11) (9) — — (7) Credit Loss Expense 40 20 19 9 10 — — 6 Other Adjustments (24) 9 — — 1 — — 4 Balance at September 30, 2021 $ 123 $ 42 $ 36 $ 21 $ 16 $ 4 $ 3 $ 15 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, 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. The aging of trade receivables is presented in the table below. Duke Energy considers receivables greater than 30 days outstanding past due. September 30, 2021 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Unbilled Revenue (a)(b) $ 826 $ 308 $ 242 $ 125 $ 117 $ 5 $ 27 $ 7 0-30 days 2,201 689 910 521 388 65 41 80 30-60 days 194 74 63 37 26 7 5 6 60-90 days 57 30 14 6 8 1 1 3 90+ days 161 68 27 5 22 31 10 9 Deferred Payment Arrangements (c) 113 66 29 21 8 2 — 6 Trade and Other Receivables $ 3,552 $ 1,235 $ 1,285 $ 715 $ 569 $ 111 $ 84 $ 111 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 Revenue (a)(b) $ 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 (c) 215 96 80 52 28 — — 7 Trade and Other Receivables $ 3,299 $ 966 $ 1,166 $ 655 $ 509 $ 102 $ 58 $ 262 (a) Unbilled revenues are recognized by applying customer billing rates to the estimated volumes of energy or natural gas delivered but not yet billed and are included within Receivables and Receivables of VIEs on the Condensed Consolidated Balance Sheets. (b) 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 Condensed Consolidated Balance Sheets of Duke Energy Ohio and Duke Energy Indiana. See Note 11 for further information. These receivables for unbilled revenues are $64 million and $115 million for Duke Energy Ohio and Duke Energy Indiana, respectively, as of September 30, 2021, and $87 million and $134 million for Duke Energy Ohio and Duke Energy Indiana, respectively, as of December 31, 2020. (c) 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.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2021
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 restricted stock units that are entitled to dividends declared on Duke Energy common stock during the restricted stock unit’s vesting periods. Dividends declared on preferred stock are recorded on the Condensed 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. Three Months Ended September 30, Nine Months Ended September 30, (in millions, except per share amounts) 2021 2020 2021 2020 Net income available to Duke Energy common stockholders $ 1,366 $ 1,265 $ 3,070 $ 1,347 Accumulated preferred stock dividends adjustment 12 12 12 13 Less: Impact of participating securities 1 1 3 2 Income from continuing operations available to Duke Energy common stockholders $ 1,377 $ 1,276 $ 3,079 $ 1,358 Weighted average common shares outstanding – basic and diluted 769 735 769 735 EPS available to Duke Energy common stockholders Basic and diluted $ 1.79 $ 1.74 $ 4.00 $ 1.85 Potentially dilutive items excluded from the calculation (a) 2 2 2 2 Dividends declared per common share $ 0.985 $ 0.965 $ 2.915 $ 2.855 Dividends declared on Series A preferred stock per depositary share (b) $ 0.359 $ 0.359 $ 1.078 $ 1.078 Dividends declared on Series B preferred stock per share (c) $ 24.375 $ 24.375 $ 48.750 $ 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. (b) 5.75% Series A Cumulative Redeemable Perpetual Preferred Stock dividends are payable quarterly in arrears on the 16th day of March, June, September and December. The preferred stock has a $25 liquidation preference per depositary share. (c) 4.875% Series B Fixed-Rate Reset Cumulative Redeemable Perpetual Preferred Stock dividends are payable semiannually in arrears on the 16th day of March and September. The preferred stock has a $1,000 liquidation preference per share.

Employee Benefit Plans

Employee Benefit Plans	9 Months Ended
	Sep. 30, 2021
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 and non-qualified, non-contributory defined benefit retirement plans. 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 monitors lump-sum benefit payment activity associated with its defined benefit retirement plans. Duke Energy does not believe it is probable that total lump-sum benefit payments will exceed the settlement threshold, defined as the sum of service cost and interest cost on projected benefit obligation components of net periodic pension costs, for any of its defined benefit retirement plans in 2021. If Duke Energy believed it were probable that total lump-sum benefit payments would exceed the settlement threshold in 2021, then a settlement charge reflecting 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, would be recognized. QUALIFIED PENSION PLANS The following tables include the components of net periodic pension costs for qualified pension plans. Three Months Ended September 30, 2021 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Service cost $ 43 $ 14 $ 13 $ 7 $ 5 $ 2 $ 2 $ 1 Interest cost on projected benefit obligation 55 13 17 8 10 2 5 2 Expected return on plan assets (139) (36) (47) (21) (25) (7) (10) (5) Amortization of actuarial loss 33 7 10 5 5 2 3 2 Amortization of prior service credit (7) (2) (1) — (1) — — (1) Amortization of settlement charges 2 1 1 — — — — 1 Net periodic pension costs $ (13) $ (3) $ (7) $ (1) $ (6) $ (1) $ — $ — Three Months Ended September 30, 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 $ 41 $ 12 $ 12 $ 6 $ 5 $ 1 $ 2 $ 1 Interest cost on projected benefit obligation 67 16 21 10 12 4 6 2 Expected return on plan assets (143) (36) (48) (22) (25) (7) (11) (5) Amortization of actuarial loss 32 7 10 4 6 2 3 2 Amortization of prior service credit (8) (2) — — — — — (2) Amortization of settlement charges 11 6 5 5 1 — 1 1 Net periodic pension costs $ — $ 3 $ — $ 3 $ (1) $ — $ 1 $ (1) Nine Months Ended September 30, 2021 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Service cost $ 131 $ 42 $ 38 $ 22 $ 16 $ 4 $ 7 $ 4 Interest cost on projected benefit obligation 165 38 52 23 29 9 14 6 Expected return on plan assets (418) (106) (141) (63) (76) (21) (30) (15) Amortization of actuarial loss 100 22 29 14 15 5 10 7 Amortization of prior service credit (22) (6) (2) (1) (1) — (1) (6) Amortization of settlement charges 6 4 2 1 — — — 1 Net periodic pension costs $ (38) $ (6) $ (22) $ (4) $ (17) $ (3) $ — $ (3) Nine Months Ended September 30, 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 $ 124 $ 38 $ 36 $ 20 $ 16 $ 3 $ 6 $ 4 Interest cost on projected benefit obligation 202 47 64 29 35 12 17 7 Expected return on plan assets (429) (108) (143) (66) (76) (21) (32) (16) Amortization of actuarial loss 96 21 30 13 17 5 9 7 Amortization of prior service credit (24) (6) (2) (1) (1) — (1) (7) Amortization of settlement charges 16 8 6 6 1 — 1 1 Net periodic pension costs $ (15) $ — $ (9) $ 1 $ (8) $ (1) $ — $ (4) NON-QUALIFIED PENSION PLANS Net periodic pension costs for non-qualified pension plans were not material for the three and nine months ended September 30, 2021, and 2020. OTHER POST-RETIREMENT BENEFIT PLANS Net periodic costs for OPEB plans were not material for the three and nine months ended September 30, 2021, and 2020.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES EFFECTIVE TAX RATES The ETRs from continuing operations for each of the Duke Energy Registrants are included in the following table. Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 Duke Energy 6.6 % 7.8 % 6.7 % (6.4) % Duke Energy Carolinas 2.9 % 12.0 % 3.6 % 13.6 % Progress Energy 12.9 % 10.4 % 11.5 % 13.4 % Duke Energy Progress 6.3 % 3.1 % 5.9 % 10.0 % Duke Energy Florida 19.1 % 21.4 % 19.1 % 20.3 % Duke Energy Ohio 13.4 % 16.7 % 15.3 % 16.6 % Duke Energy Indiana 15.8 % 19.6 % 16.3 % 19.4 % Piedmont 25.0 % 16.7 % 8.4 % 3.7 % The decrease in the ETR for Duke Energy for the three months ended September 30, 2021, was primarily due to an increase in the amortization of excess deferred taxes. The increase in the ETR for Duke Energy for the nine months ended September 30, 2021, was primarily due to the cancellation of the ACP pipeline project recorded in the prior year, partially offset by an increase in the amortization of excess deferred taxes. The decrease in the ETR for Duke Energy Carolinas for the three and nine months ended September 30, 2021, was primarily due to an increase in the amortization of excess deferred taxes. The increase in the ETR for Progress Energy for the three months ended September 30, 2021, was primarily due to a decrease in the amortization of excess deferred taxes. The decrease in the ETR for Progress Energy for the nine months ended September 30, 2021, was primarily due to an increase in the amortization of excess deferred taxes. The increase in the ETR for Duke Energy Progress for the three months ended September 30, 2021, was primarily due to a decrease in the amortization of excess deferred taxes. The decrease in the ETR for Duke Energy Progress for the nine months ended September 30, 2021, was primarily due to an increase in the amortization of excess deferred taxes. The decrease in the ETR for Duke Energy Florida for the three and nine months ended September 30, 2021, was primarily due to unfavorable tax adjustments in the prior year. The decrease in the ETR for Duke Energy Ohio for the three and nine months ended September 30, 2021, was primarily due to an increase in the amortization of excess deferred taxes. The decrease in the ETR for Duke Energy Indiana for the three and nine months ended September 30, 2021, was primarily due to an increase in the amortization of excess deferred taxes.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTSFor information on subsequent events related to regulatory matters, commitments and contingencies and debt and credit facilities, see Notes 3, 4 and 5.

Organization and Basis of Pre_2

Organization and Basis of Presentation (Policy)	9 Months Ended
	Sep. 30, 2021
Policy Text Block [Line Items]
Basis of Presentation	BASIS OF PRESENTATION These Condensed Consolidated Financial Statements have been prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Regulation S-X. Accordingly, these Condensed Consolidated Financial Statements do not include all information and notes required by GAAP for annual financial statements and should be read in conjunction with the Consolidated Financial Statements in the Duke Energy Registrants’ combined Annual Report on Form 10-K for the year ended December 31, 2020. The information in these combined notes relates to each of the Duke Energy Registrants as noted in the Index to Combined Notes to Condensed Consolidated Financial Statements. However, none of the registrants make any representations as to information related solely to Duke Energy or the subsidiaries of Duke Energy other than itself. These Condensed Consolidated Financial Statements, in the opinion of the respective companies’ management, reflect all normal recurring adjustments necessary to fairly present the financial position and results of operations of each of the Duke Energy Registrants. Amounts reported in Duke Energy’s interim Condensed Consolidated Statements of Operations and each of the Subsidiary Registrants’ interim Condensed Consolidated Statements of Operations and Comprehensive Income are not necessarily indicative of amounts expected for the respective annual periods due to effects of seasonal temperature variations on energy consumption, regulatory rulings, timing of maintenance on electric generating units, changes in mark-to-market valuations, changing commodity prices and other factors. In preparing financial statements that conform to GAAP, management 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.
Basis of Consolidation and Noncontrolling Interest	BASIS OF CONSOLIDATION These Condensed 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 11 for additional information on VIEs. These Condensed Consolidated Financial Statements also reflect the Duke Energy Registrants’ proportionate share of certain jointly owned generation and transmission facilities. 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 Condensed Consolidated Balance Sheet. Several operating agreements of Duke Energy's subsidiaries with noncontrolling interest are subject to allocations of earnings, 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 Hypothetical Liquidation at Book Value (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 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.
Cash, Cash Equivalents, and Restricted Cash	CASH, CASH EQUIVALENTS AND RESTRICTED CASHDuke Energy, Progress Energy and Duke Energy Florida have restricted cash balances related primarily to collateral assets, escrow deposits and VIEs. See Notes 9 and 11 for additional information. Restricted cash amounts are included in Other within Current Assets and Other Noncurrent Assets on the Condensed Consolidated Balance Sheets.
New Accounting Standards	NEW ACCOUNTING STANDARDS The following new accounting standard was adopted by the Duke Energy Registrants in 2021. Leases with Variable Lease Payments. In July 2021, the Financial Accounting Standards Board (FASB) issued new accounting guidance requiring lessors to classify a lease with variable lease payments that do not depend on a reference index or rate as an operating lease if both of the following are met: (1) the lease would have to be classified as a sales-type or direct financing lease under prior guidance, and (2) the lessor would have recognized a day-one loss. Duke Energy elected to adopt the guidance immediately upon issuance of the new standard and will be applying the new standard prospectively to new lease arrangements meeting the criteria. Duke Energy does not currently have any lease arrangements that this new accounting guidance will materially impact. The following accounting standard was adopted by the Duke Energy Registrants in 2020. Current Expected 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. Duke Energy recorded cumulative effects of changes in accounting principles related to the adoption of the new credit loss standard for allowances for credit losses of trade and other receivables, insurance receivables and financial guarantees. These amounts are included in the Condensed Consolidated Balance Sheets in Receivables, Receivables of VIEs, Other Noncurrent Assets and Other Noncurrent Liabilities. See Notes 4 and 12 for more information. 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: January 1, 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 The following new accounting standard has been issued but not yet adopted by the Duke Energy Registrants as of September 30, 2021. 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 2022. 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 2022 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 2022. 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.
Environmental Costs	Liabilities are recorded when losses become probable and are reasonably estimable.Costs are typically expensed as Operation, maintenance and other on the Condensed Consolidated Statements of Operations unless regulatory recovery of the costs is deemed probable.
Derivatives	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 Condensed Consolidated Statements of Operations and Comprehensive Income. 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 loss for the three and nine months ended September 30, 2021, and 2020, were 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 natural gas costs volatility for customers.
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.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.
Revenue from Contract with Customer	Duke Energy earns substantially all of its revenues through its reportable segments, Electric Utilities and Infrastructure, Gas Utilities and Infrastructure and Commercial Renewables.
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. Duke Energy’s participating securities are restricted stock units that are entitled to dividends declared on Duke Energy common stock during the restricted stock unit’s vesting periods. Dividends declared on preferred stock are recorded on the Condensed 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.

Organization and Basis of Pre_3

Organization and Basis of Presentation (Tables)	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Cash Received and Allocated Losses from Subsidiaries, Noncontrolling Interest	The following table presents allocated losses to noncontrolling interest for the three and nine months ended September 30, 2021, and 2020. Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2021 2020 2021 2020 Noncontrolling Interest Allocation of Income Allocated losses to noncontrolling tax equity members utilizing the HLBV method $ 119 $ 59 $ 217 $ 187 Allocated losses to noncontrolling members based on pro rata shares of ownership 10 11 30 21 Total Noncontrolling Interest Allocated Losses $ 129 $ 70 $ 247 $ 208
Schedule of Cash, Cash Equivalents and Restricted Cash	The following table presents the components of cash, cash equivalents and restricted cash included in the Condensed Consolidated Balance Sheets. September 30, 2021 December 31, 2020 Duke Duke Duke Progress Energy Duke Progress Energy Energy Energy Florida Energy Energy Florida Current Assets Cash and cash equivalents $ 548 $ 102 $ 40 $ 259 $ 59 $ 11 Other 194 17 17 194 39 39 Other Noncurrent Assets Other 1 — — 103 102 — Total cash, cash equivalents and restricted cash $ 743 $ 119 $ 57 $ 556 $ 200 $ 50
Schedule of Utility Inventory	The components of inventory are presented in the tables below. September 30, 2021 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 $ 2,317 $ 779 $ 1,009 $ 674 $ 336 $ 85 $ 305 $ 11 Coal 312 152 89 45 43 10 61 — Natural gas, oil and other fuel 271 38 157 96 60 19 1 57 Total inventory $ 2,900 $ 969 $ 1,255 $ 815 $ 439 $ 114 $ 367 $ 68 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 fuel 294 39 183 107 76 16 1 56 Total inventory $ 3,167 $ 1,010 $ 1,375 $ 911 $ 464 $ 110 $ 473 $ 68
Schedule 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: January 1, 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)	9 Months Ended
	Sep. 30, 2021
Segment Reporting Information [Line Items]
Business Segment Data	Business segment information is presented in the following tables. Segment assets presented exclude intercompany assets. Three Months Ended September 30, 2021 Electric Gas Total Utilities and Utilities and Commercial Reportable (in millions) Infrastructure Infrastructure Renewables Segments Other Eliminations Total Unaffiliated revenues $ 6,560 $ 266 $ 117 $ 6,943 $ 8 $ — $ 6,951 Intersegment revenues 9 23 — 32 20 (52) — Total revenues $ 6,569 $ 289 $ 117 $ 6,975 $ 28 $ (52) $ 6,951 Segment income (loss) (a) $ 1,425 $ (3) $ 78 $ 1,500 $ (134) $ — $ 1,366 Less: Noncontrolling interests 129 Add: Preferred stock dividend 39 Net Income $ 1,276 Segment assets $ 141,565 $ 14,692 $ 7,037 $ 163,294 $ 3,717 $ (4) $ 167,007 Three Months Ended September 30, 2020 Electric Gas Total Utilities and Utilities and Commercial Reportable (in millions) Infrastructure Infrastructure Renewables Segments Other Eliminations Total Unaffiliated revenues $ 6,371 $ 217 $ 126 $ 6,714 $ 7 $ — $ 6,721 Intersegment revenues 8 24 — 32 17 (49) — Total revenues $ 6,379 $ 241 $ 126 $ 6,746 $ 24 $ (49) $ 6,721 Segment income (loss) (b) $ 1,381 $ (73) $ 60 $ 1,368 $ (103) $ — $ 1,265 Less: Noncontrolling interests 70 Add: Preferred stock dividend 39 Net Income $ 1,234 (a) G as Utilities and Infrastructure includes $3 million, recorded within Equity in earnings (losses) of unconsolidated affiliates on the Condensed Consolidated Statements of Operations, related to gas pipeline investments. See Note 3 for additional information. Other includes $8 million recorded within Impairment of assets and other charges, $1 million within Operations, maintenance and other on the Condensed Consolidated Statements of Operations, related to the workplace and workforce realignment. See Note 1 for additional i nformation. Electric Utilities and Infrastructure includes $160 million recorded within Impairment of assets and other charges, $77 million within Other Income and expenses, $5 million within Operations, maintenance and other, $13 million within Regulated electric operating revenues and $3 million within Interest expense on the Duke Energy Carolinas' Condensed Consolidated Statement of Operations related to the 2018 South Carolina rate cases and the CCR settlement and insurance proceeds distributed in accordance with that agreement; it also includes $42 million recorded within Impairment of assets and other charges, $34 million within Other Income and expenses , $7 million within Operations, maintenance, and other, $15 million within Regulated electric operating revenues and $5 million within Interest expense on the Duke Energy Progress' Condensed Consolidated Statement of Operations. See Notes 3 and 4 for more information. (b) Electric Utilities and Infrastructure includes $19 million recorded within Impairment charges and $8 million recorded within Operations, maintenance and other on the Duke Energy Carolinas' Condensed Consolidated Statements of Operations related to a partial settlement in the Duke Energy Carolinas' 2019 North Carolina rate case and $8 million recorded within Operations, maintenance and other on Duke Energy Progress' Condensed Consolidated Statements of Operation related to a partial settlement in the Duke Energy Progress' 2019 North Carolina rate case. See Note 3 for more information. Additionally, Electric Utilities and Infrastructure includes $5 million of Impairment charges related to gas pipeline assets recorded on Duke Energy Progress' Condensed Consolidated Statement of Operations. Gas Utilities and Infrastructure includes $78 million recorded within Equity in earnings (losses) of unconsolidated affiliates on the Condensed Consolidated Statements of Operations and $7 million in Impairment charges recorded on the Piedmont Condensed Consolidated Statements of Operations related to gas pipeline investments. Nine Months Ended September 30, 2021 Electric Gas Total Utilities and Utilities and Commercial Reportable (in millions) Infrastructure Infrastructure Renewables Segments Other Eliminations Total Unaffiliated revenues $ 17,161 $ 1,323 $ 355 $ 18,839 $ 20 $ — $ 18,859 Intersegment revenues 24 68 — 92 61 (153) — Total revenues $ 17,185 $ 1,391 $ 355 $ 18,931 $ 81 $ (153) $ 18,859 Segment income (loss) (a) $ 3,180 $ 259 $ 152 $ 3,591 $ (521) $ — $ 3,070 Less: Noncontrolling interests 247 Add: Preferred stock dividend 92 Net Income $ 2,915 Nine Months Ended September 30, 2020 Electric Gas Total Utilities and Utilities and Commercial Reportable (in millions) Infrastructure Infrastructure Renewables Segments Other Eliminations Total Unaffiliated revenues $ 16,571 $ 1,122 $ 378 $ 18,071 $ 20 $ — $ 18,091 Intersegment revenues 25 72 — 97 53 (150) — Total revenues $ 16,596 $ 1,194 $ 378 $ 18,168 $ 73 $ (150) $ 18,091 Segment income (loss) (b) $ 2,839 $ (1,400) $ 207 $ 1,646 $ (299) $ — $ 1,347 Less: Noncontrolling interests 208 Add: Preferred stock dividend 93 Net Income $ 1,232 (a) Gas Utilities and Infrastructure includes $19 million, recorded within Equity in earnings (losses) of unconsolidated affiliates on the Condensed Consolidated Statements of Operations, related to gas pipeline investments. See Note 3 for additional information. Commercial Renewables includes a $35 million loss related to Texas Storm Uri, of which ($8 million) is recorded within Nonregulated electric and other revenues, $2 million within Operations, maintenance and other, $29 million within Equity in earnings (losses) of unconsolidated affiliates and $12 million within Loss Attributable to Noncontrolling Interests on the Condensed Consolidated Statements of Operations. See Note 4 for additional information. Other includes $139 million recorded within Impairment of assets and other charges, $28 million within Operations, maintenance and other, and $17 million within Depreciation and amortization on the Condensed Consolidated Statements of Operations, related to the workplace and workplace realignment. See Note 1 for additional information. Electric Utilities and Infrastructure includes $160 million recorded within Impairment of assets and other charges, $77 million within Other Income and expenses, $5 million within Operations, maintenance and other, $13 million within regulated operating revenues and $3 million within interest expense on the Duke Energy Carolinas' Condensed Consolidated Statement of Operations related to the 2018 South Carolina rate cases and the CCR settlement and insurance proceeds distributed in accordance with that agreement; it also includes $42 million recorded within Impairment of assets and other charges, $34 million within Other Income and expenses, $7 million within Operations, maintenance, and other, $15 million within Regulated electric operating revenues and $5 million wit hin interest expense on the Duke Energy Progress' Condensed Consolidated Statement of Operations. See Notes 3 and 4 for more information. (b) Gas Utilities and Infrastructure includes $2 billion recorded within Equity in earnings (losses) of unconsolidated affiliates on the Condensed Consolidated Statements of Operations, related to gas pipeline investments. See Note 3 for additional information. Other includes a $98 million reversal, included in Operations, maintenance and other on the Condensed Consolidated Statements of Operations, of 2018 severance costs due to a partial settlement in the Duke Energy Carolinas' 2019 North Carolina rate case. See Note 3 for additional information. Electric Utilities and Infrastructure includes $19 million recorded within Impairment charges and $8 million recorded within Operations, maintenance and other on the Duke Energy Carolinas' Condensed Consolidated Statements of Operations related to a partial settlement in the Duke Energy Carolinas' 2019 North Carolina rate case and $8 million recorded within Operations, maintenance and other on Duke Energy Progress' Condensed Consolidated Statements of Operation related to a partial settlement in the Duke Energy Progress' 2019 North Carolina rate case. See Note 3 for more information. Additionally, Electric Utilities and Infrastructure includes $5 million of Impairment charges related to gas pipeline assets recorded on Duke Energy Progress' Condensed Consolidated Statement of Operations in the prior year.
Duke Energy Ohio
Segment Reporting Information [Line Items]
Business Segment Data	Three Months Ended September 30, 2021 Electric Gas Total Utilities and Utilities and Reportable (in millions) Infrastructure Infrastructure Segments Other Eliminations Total Total revenues $ 413 $ 93 $ 506 $ — $ — $ 506 Segment income/Net (loss) income $ 48 $ 11 $ 59 $ (1) $ — $ 58 Segment assets $ 6,716 $ 3,783 $ 10,499 $ 27 $ (21) $ 10,505 Three Months Ended September 30, 2020 Electric Gas Total Utilities and Utilities and Reportable (in millions) Infrastructure Infrastructure Segments Other Total Total revenues $ 394 $ 79 $ 473 $ — $ 473 Segment income/Net (loss) income $ 63 $ 9 $ 72 $ (2) $ 70 Nine Months Ended September 30, 2021 Electric Gas Total Utilities and Utilities and Reportable (in millions) Infrastructure Infrastructure Segments Other Total Total revenues $ 1,119 $ 375 $ 1,494 $ — $ 1,494 Segment income/Net (loss) income $ 122 $ 77 $ 199 $ (11) $ 188 Nine Months Ended September 30, 2020 Electric Gas Total Utilities and Utilities and Reportable (in millions) Infrastructure Infrastructure Segments Other Total Total revenues $ 1,070 $ 324 $ 1,394 $ — $ 1,394 Segment income/Net (loss) income $ 137 $ 68 $ 205 $ (4) $ 201

Regulatory Matters (Tables)

Regulatory Matters (Tables)	9 Months Ended
	Sep. 30, 2021
Regulated Operations [Abstract]
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 Condensed Consolidated Balance Sheets as of September 30, 2021, and exclude capitalized asset retirement costs. Remaining Net Capacity Book Value (in MW) (in millions) Duke Energy Carolinas Allen Steam Station Units 1-2 (a) 324 $ 19 Allen Steam Station Units 4-5 (b) 516 362 Cliffside Unit 5 (b) 544 367 Duke Energy Progress Mayo Unit 1 (b) 704 640 Roxboro Units 3-4 (b) 1,392 465 Duke Energy Florida Crystal River Units 4-5 (c) 1,410 1,658 Duke Energy Indiana (d) Gibson Units 1-5 (e) 2,822 1,814 Cayuga Units 1-2 (e) 995 713 Total Duke Energy 8,707 $ 6,038 (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, was retired in March 2021. (b) These units were 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. The NCUC issued orders in the 2019 rate cases of Duke Energy Carolinas and Duke Energy Progress on March 31, 2021, and April 16, 2021, respectively, in which the proposals to shorten the remaining depreciable lives of these units were denied, while indicating the IRP proceeding was the appropriate proceeding for the review of generating plant retirements. (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. The settlement was approved by the FPSC on May 4, 2021. (d) Gallagher Units 2 and 4 with a total capacity of 280 MW and a total net book value of $102 million at December 31, 2020, were retired on June 1, 2021. (e) 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.

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Schedule of Reserves	The following table contains 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 Condensed Consolidated Balance Sheets. (in millions) September 30, 2021 December 31, 2020 Reserves for Environmental Remediation Duke Energy $ 74 $ 75 Duke Energy Carolinas 19 19 Progress Energy 17 19 Duke Energy Progress 6 6 Duke Energy Florida 11 12 Duke Energy Ohio 21 22 Duke Energy Indiana 5 6 Piedmont 12 10

Debt and Credit Facilities (Tab

Debt and Credit Facilities (Tables)	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	The following table summarizes significant debt issuances (in millions). Nine Months Ended September 30, 2021 Duke Duke Duke Maturity Interest Duke Energy Energy Energy Issuance Date Date Rate Energy (Parent) Carolinas Progress Piedmont Unsecured Debt March 2021 (a) March 2031 2.500 % $ 350 $ — $ — $ — $ 350 June 2021 (b)(c) June 2023 2.500 % 500 500 — — — June 2021 (c) June 2031 2.550 % 1,000 1,000 — — — June 2021 (c) June 2041 3.300 % 750 750 — — — June 2021 (c) June 2051 3.500 % 750 750 — — — September 2021 (d) January 2082 3.250 % 500 500 — — — First Mortgage Bonds April 2021 (e) April 2031 2.550 % 550 — 550 — — April 2021 (e) April 2051 3.450 % 450 — 450 — — August 2021 (f) August 2031 2.000 % 650 — — 650 — August 2021 (f) August 2051 2.900 % 450 — — 450 — Total issuances $ 5,950 $ 3,500 $ 1,000 $ 1,100 $ 350 (a) Debt issued to repay at maturity $160 million senior unsecured notes due June 2021, pay down short-term debt and for general corporate purposes. (b) Debt issuance has a floating interest rate. (c) Debt issued to repay $1.75 billion of Duke Energy (Parent) 2021 debt maturities, to repay a portion of short-term debt and for general corporate purposes. (d) Debt issued to repay in October 2021 $500 million of Duke Energy (Parent) unsecured notes. The interest rate resets every five years. (e) Debt issued to repay at maturity $500 million first mortgage bonds due June 2021, pay down short-term debt and for general company purposes. (f) Debt issued to repay at maturity a total of $600 million first mortgage bonds due September 2021, pay down short-term debt and for general company purposes. The following table shows the significant components of Current maturities of long-term debt on the Condensed 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 September 30, 2021 Unsecured Debt Duke Energy (Parent) (a) October 2021 5.125 % 500 Duke Energy Florida (b) November 2021 0.372 % 200 Duke Energy Progress (b) February 2022 0.305 % 700 Duke Energy (Parent) March 2022 3.227 % 300 Duke Energy (Parent) (b) March 2022 0.764 % 300 Progress Energy April 2022 3.150 % 450 Duke Energy (Parent) August 2022 3.050 % 500 Duke Energy (Parent) August 2022 2.400 % 500 First Mortgage Bonds Duke Energy Indiana January 2022 8.850 % 53 Duke Energy Carolinas May 2022 3.350 % 350 Duke Energy Progress May 2022 2.800 % 500 Other (c) 520 Current maturities of long-term debt $ 4,873 (a) Junior unsecured notes due January 2073 were redeemed on October 7, 2021. (b) Debt has a floating interest rate. (c) Includes finance lease obligations, amortizing debt, tax-exempt bonds with mandatory put options and small bullet maturities.
Schedule Of Line Of Credit Facilities	The table below includes the current borrowing sublimits and available capacity under these credit facilities. September 30, 2021 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 $ 1,275 $ 1,150 $ 850 $ 775 $ 600 $ 700 Reduction to backstop issuances Commercial paper (b) (1,611) 389 (375) (253) (527) (419) (150) (276) Outstanding letters of credit (31) (25) (4) (2) — — — — Tax-exempt bonds (81) — — — — — (81) — Available capacity under the Master Credit Facility $ 6,277 $ 3,014 $ 896 $ 895 $ 323 $ 356 $ 369 $ 424 (a) Represents the sublimit of each borrower. September 30, 2021 (in millions) Facility size Amount drawn Duke Energy (Parent) Three (a) $ 1,000 $ 500 (a) During March 2021, Duke Energy extended the maturity date of the Three-Year Revolving Credit Facility from May 2022 to May 2024.

Goodwill (Tables)

Goodwill (Tables)	9 Months Ended
	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill By Reportable Operating Segment	The following table presents the goodwill by reportable segment included on Duke Energy's Condensed Consolidated Balance Sheets at September 30, 2021, and December 31, 2020. Electric Utilities Gas Utilities Commercial (in millions) and Infrastructure and Infrastructure Renewables Total Goodwill balance $ 17,379 $ 1,924 $ 122 $ 19,425 Accumulated impairment charges — — (122) (122) Goodwill, adjusted for accumulated impairment charges $ 17,379 $ 1,924 $ — $ 19,303

Related Party Transactions (Tab

Related Party Transactions (Tables)	9 Months Ended
	Sep. 30, 2021
Related Party Transactions [Abstract]
Schedule of Related Party Transactions, Other Revenue and Expense	Material amounts related to transactions with related parties included on the Condensed Consolidated Statements of Operations and Comprehensive Income are presented in the following table. Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2021 2020 2021 2020 Duke Energy Carolinas Corporate governance and shared service expenses (a) $ 207 $ 198 $ 653 $ 528 Indemnification coverages (b) 6 5 18 15 Joint Dispatch Agreement (JDA) revenue (c) 6 6 32 16 JDA expense (c) 68 28 133 72 Intercompany natural gas purchases (d) 14 10 43 26 Progress Energy Corporate governance and shared service expenses (a) $ 201 $ 185 $ 615 $ 520 Indemnification coverages (b) 10 9 31 27 JDA revenue (c) 68 28 133 72 JDA expense (c) 6 6 32 16 Intercompany natural gas purchases (d) 19 18 56 56 Duke Energy Progress Corporate governance and shared service expenses (a) $ 121 $ 113 $ 367 $ 301 Indemnification coverages (b) 4 4 14 13 JDA revenue (c) 68 28 133 72 JDA expense (c) 6 6 32 16 Intercompany natural gas purchases (d) 19 18 56 56 Duke Energy Florida Corporate governance and shared service expenses (a) $ 80 $ 72 $ 248 $ 219 Indemnification coverages (b) 6 5 17 14 Duke Energy Ohio Corporate governance and shared service expenses (a) $ 79 $ 80 $ 237 $ 241 Indemnification coverages (b) 1 1 3 3 Duke Energy Indiana Corporate governance and shared service expenses (a) $ 96 $ 102 $ 302 $ 300 Indemnification coverages (b) 2 2 6 6 Piedmont Corporate governance and shared service expenses (a) $ 32 $ 31 $ 101 $ 102 Indemnification coverages (b) 1 1 3 2 Intercompany natural gas sales (d) 33 28 99 82 Natural gas storage and transportation costs (e) 6 6 17 17 (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 and Impairment of assets and other charges on the Condensed 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 Condensed 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 Condensed 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 Condensed 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 September 30, 2021 Intercompany income tax receivable $ — $ 36 $ — $ 8 $ 1 $ — $ 14 Intercompany income tax payable 133 — 51 — — 17 — December 31, 2020 Intercompany income tax receivable $ — $ — $ — $ — $ — $ 9 $ 10 Intercompany income tax payable 31 33 46 35 2 — —

Derivatives and Hedging (Tables

Derivatives and Hedging (Tables)	9 Months Ended
	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Notional Amounts of Outstanding Derivative Positions	The following table shows notional amounts of outstanding derivatives related to interest rate risk. September 30, 2021 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Cash flow hedges $ 2,094 $ — $ — $ — $ — $ — Undesignated contracts 1,371 350 900 400 500 27 Total notional amount (a) $ 3,465 $ 350 $ 900 $ 400 $ 500 $ 27 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 (a) Duke Energy includes amounts related to consolidated VIEs of $594 million in cash flow hedges and $94 million in undesignated contracts as of September 30, 2021, and $632 million in cash flow hedges as of December 31, 2020. 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. September 30, 2021 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy Carolinas Energy Progress Ohio Indiana Piedmont Electricity (GWh) (a) 29,044 — — — 3,004 15,881 — Natural gas (millions of dekatherms) 772 230 190 190 — 7 345 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 dekatherms) 678 145 158 158 — 2 373 (a) Duke Energy includes 10,159 GWh and 22,048 GWh related to cash flow hedges as of September 30, 2021, and December 31, 2020, respectively.
Location And Fair Value Of Derivatives Recognized in the Condensed 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 Condensed 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 September 30, 2021 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 $ 359 $ 171 $ 135 $ 135 $ — $ 4 $ 36 $ 12 Noncurrent 177 100 78 78 — — — — Total Derivative Assets – Commodity Contracts $ 536 $ 271 $ 213 $ 213 $ — $ 4 $ 36 $ 12 Interest Rate Contracts Designated as Hedging Instruments Current $ 2 $ — $ — $ — $ — $ — $ — $ — Noncurrent 3 — — — — — — — Not Designated as Hedging Instruments Current $ 2 $ — $ 2 $ 2 $ — $ — $ — $ — Total Derivative Assets – Interest Rate Contracts $ 7 $ — $ 2 $ 2 $ — $ — $ — $ — Total Derivative Assets $ 543 $ 271 $ 215 $ 215 $ — $ 4 $ 36 $ 12 Derivative Liabilities September 30, 2021 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 $ 37 $ — $ — $ — $ — $ — $ — — Noncurrent 120 — — — — — — — Not Designated as Hedging Instruments Current $ 33 $ 12 $ — $ — $ — $ — $ 2 $ 20 Noncurrent 128 — — — — — — 128 Total Derivative Liabilities – Commodity Contracts $ 318 $ 12 $ — $ — $ — $ — $ 2 $ 148 Interest Rate Contracts Designated as Hedging Instruments Current $ 45 $ — $ — $ — $ — $ — $ — $ — Noncurrent 29 — — — — — — — Not Designated as Hedging Instruments Current 19 6 12 — 12 1 — — Noncurrent 4 — — — — 4 — — Total Derivative Liabilities – Interest Rate Contracts $ 97 $ 6 $ 12 $ — $ 12 $ 5 $ — $ — Total Derivative Liabilities $ 415 $ 18 $ 12 $ — $ 12 $ 5 $ 2 $ 148 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
Offsetting Assets	The following tables present the line items on the Condensed 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 September 30, 2021 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 $ 363 $ 171 $ 137 $ 137 $ — $ 4 $ 36 $ 12 Gross amounts offset (143) (87) (56) (56) — — — — Net amounts presented in Current Assets: Other $ 220 $ 84 $ 81 $ 81 $ — $ 4 $ 36 $ 12 Noncurrent Gross amounts recognized $ 180 $ 100 $ 78 $ 78 $ — $ — $ — $ — Gross amounts offset (71) (45) (26) (26) — — — — Net amounts presented in Other Noncurrent Assets: Other $ 109 $ 55 $ 52 $ 52 $ — $ — $ — $ — Derivative Liabilities September 30, 2021 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 $ 134 $ 18 $ 12 $ — $ 12 $ 1 $ 2 $ 20 Gross amounts offset — — — — — — — — Net amounts presented in Current Liabilities: Other $ 134 $ 18 $ 12 $ — $ 12 $ 1 $ 2 $ 20 Noncurrent Gross amounts recognized $ 281 $ — $ — $ — $ — $ 4 $ — $ 128 Gross amounts offset — — — — — — — — Net amounts presented in Other Noncurrent Liabilities: Other $ 281 $ — $ — $ — $ — $ 4 $ — $ 128 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
Offsetting Liabilities	The following tables present the line items on the Condensed 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 September 30, 2021 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 $ 363 $ 171 $ 137 $ 137 $ — $ 4 $ 36 $ 12 Gross amounts offset (143) (87) (56) (56) — — — — Net amounts presented in Current Assets: Other $ 220 $ 84 $ 81 $ 81 $ — $ 4 $ 36 $ 12 Noncurrent Gross amounts recognized $ 180 $ 100 $ 78 $ 78 $ — $ — $ — $ — Gross amounts offset (71) (45) (26) (26) — — — — Net amounts presented in Other Noncurrent Assets: Other $ 109 $ 55 $ 52 $ 52 $ — $ — $ — $ — Derivative Liabilities September 30, 2021 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 $ 134 $ 18 $ 12 $ — $ 12 $ 1 $ 2 $ 20 Gross amounts offset — — — — — — — — Net amounts presented in Current Liabilities: Other $ 134 $ 18 $ 12 $ — $ 12 $ 1 $ 2 $ 20 Noncurrent Gross amounts recognized $ 281 $ — $ — $ — $ — $ 4 $ — $ 128 Gross amounts offset — — — — — — — — Net amounts presented in Other Noncurrent Liabilities: Other $ 281 $ — $ — $ — $ — $ 4 $ — $ 128 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

Investments in Debt and Equit_2

Investments in Debt and Equity Securities (Tables)	9 Months Ended
	Sep. 30, 2021
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI	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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value NDTF Cash and cash equivalents $ — $ — $ 164 $ — $ — $ 177 Equity securities 4,700 35 6,754 4,138 54 6,235 Corporate debt securities 44 5 847 76 1 806 Municipal bonds 13 1 296 22 — 370 U.S. government bonds 34 8 1,605 51 — 1,361 Other debt securities 4 1 195 8 — 180 Total NDTF Investments $ 4,795 $ 50 $ 9,861 $ 4,295 $ 55 $ 9,129 Other Investments Cash and cash equivalents $ — $ — $ 87 $ — $ — $ 127 Equity securities 83 — 145 79 — 146 Corporate debt securities 4 1 130 8 — 110 Municipal bonds 3 1 69 5 — 86 U.S. government bonds — — 50 — — 42 Other debt securities — — 34 — — 47 Total Other Investments $ 90 $ 2 $ 515 $ 92 $ — $ 558 Total Investments $ 4,885 $ 52 $ 10,376 $ 4,387 $ 55 $ 9,687
Debt Securities, Available-for-sale	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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value NDTF Cash and cash equivalents $ — $ — $ 164 $ — $ — $ 177 Equity securities 4,700 35 6,754 4,138 54 6,235 Corporate debt securities 44 5 847 76 1 806 Municipal bonds 13 1 296 22 — 370 U.S. government bonds 34 8 1,605 51 — 1,361 Other debt securities 4 1 195 8 — 180 Total NDTF Investments $ 4,795 $ 50 $ 9,861 $ 4,295 $ 55 $ 9,129 Other Investments Cash and cash equivalents $ — $ — $ 87 $ — $ — $ 127 Equity securities 83 — 145 79 — 146 Corporate debt securities 4 1 130 8 — 110 Municipal bonds 3 1 69 5 — 86 U.S. government bonds — — 50 — — 42 Other debt securities — — 34 — — 47 Total Other Investments $ 90 $ 2 $ 515 $ 92 $ — $ 558 Total Investments $ 4,885 $ 52 $ 10,376 $ 4,387 $ 55 $ 9,687
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 three and nine months ended September 30, 2021, and 2020, were as follows. Three Months Ended Nine Months Ended (in millions) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 FV-NI: Realized gains $ 34 $ 13 $ 320 $ 338 Realized losses 40 16 100 148 AFS: Realized gains 17 26 51 73 Realized losses 15 19 46 38
Investments Classified by Contractual Maturity Date	The table below summarizes the maturity date for debt securities. September 30, 2021 Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Indiana Due in one year or less $ 151 $ 3 $ 121 $ 22 $ 99 $ 5 Due after one through five years 954 343 548 244 304 18 Due after five through 10 years 639 268 286 247 39 8 Due after 10 years 1,482 847 553 517 36 15 Total $ 3,226 $ 1,461 $ 1,508 $ 1,030 $ 478 $ 46
Duke Energy Carolinas
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI	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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value NDTF Cash and cash equivalents $ — $ — $ 60 $ — $ — $ 30 Equity securities 2,725 14 3,912 2,442 23 3,685 Corporate debt securities 27 3 495 49 1 510 Municipal bonds 1 — 24 6 — 91 U.S. government bonds 18 2 752 25 — 475 Other debt securities 4 1 190 7 — 174 Total NDTF Investments $ 2,775 $ 20 $ 5,433 $ 2,529 $ 24 $ 4,965
Debt Securities, Available-for-sale	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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value NDTF Cash and cash equivalents $ — $ — $ 60 $ — $ — $ 30 Equity securities 2,725 14 3,912 2,442 23 3,685 Corporate debt securities 27 3 495 49 1 510 Municipal bonds 1 — 24 6 — 91 U.S. government bonds 18 2 752 25 — 475 Other debt securities 4 1 190 7 — 174 Total NDTF Investments $ 2,775 $ 20 $ 5,433 $ 2,529 $ 24 $ 4,965
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 three and nine months ended September 30, 2021, and 2020, were as follows. Three Months Ended Nine Months Ended (in millions) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 FV-NI: Realized gains $ 25 $ 10 $ 243 $ 46 Realized losses 29 12 68 82 AFS: Realized gains 10 20 35 50 Realized losses 10 17 32 30
Progress Energy
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI	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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value NDTF Cash and cash equivalents $ — $ — $ 104 $ — $ — $ 147 Equity securities 1,975 21 2,842 1,696 31 2,550 Corporate debt securities 17 2 352 27 — 296 Municipal bonds 12 1 272 16 — 279 U.S. government bonds 16 6 853 26 — 886 Other debt securities — — 5 1 — 6 Total NDTF Investments $ 2,020 $ 30 $ 4,428 $ 1,766 $ 31 $ 4,164 Other Investments Cash and cash equivalents $ — $ — $ 18 $ — $ — $ 106 Municipal bonds 2 — 26 3 — 26 Total Other Investments $ 2 $ — $ 44 $ 3 $ — $ 132 Total Investments $ 2,022 $ 30 $ 4,472 $ 1,769 $ 31 $ 4,296
Debt Securities, Available-for-sale	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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value NDTF Cash and cash equivalents $ — $ — $ 104 $ — $ — $ 147 Equity securities 1,975 21 2,842 1,696 31 2,550 Corporate debt securities 17 2 352 27 — 296 Municipal bonds 12 1 272 16 — 279 U.S. government bonds 16 6 853 26 — 886 Other debt securities — — 5 1 — 6 Total NDTF Investments $ 2,020 $ 30 $ 4,428 $ 1,766 $ 31 $ 4,164 Other Investments Cash and cash equivalents $ — $ — $ 18 $ — $ — $ 106 Municipal bonds 2 — 26 3 — 26 Total Other Investments $ 2 $ — $ 44 $ 3 $ — $ 132 Total Investments $ 2,022 $ 30 $ 4,472 $ 1,769 $ 31 $ 4,296
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 three and nine months ended September 30, 2021, and 2020, were as follows. Three Months Ended Nine Months Ended (in millions) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 FV-NI: Realized gains $ 9 $ 3 $ 77 $ 292 Realized losses 11 4 32 66 AFS: Realized gains 7 6 14 17 Realized losses 6 2 12 7
Duke Energy Progress
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI	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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value NDTF Cash and cash equivalents $ — $ — $ 92 $ — $ — $ 76 Equity securities 1,882 21 2,736 1,617 31 2,459 Corporate debt securities 17 2 287 27 — 296 Municipal bonds 12 1 272 16 — 279 U.S. government bonds 16 2 466 26 — 412 Other debt securities — — 5 1 — 6 Total NDTF Investments $ 1,927 $ 26 $ 3,858 $ 1,687 $ 31 $ 3,528 Other Investments Cash and cash equivalents $ — $ — $ 16 $ — $ — $ 1 Total Other Investments $ — $ — $ 16 $ — $ — $ 1 Total Investments $ 1,927 $ 26 $ 3,874 $ 1,687 $ 31 $ 3,529
Debt Securities, Available-for-sale	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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value NDTF Cash and cash equivalents $ — $ — $ 92 $ — $ — $ 76 Equity securities 1,882 21 2,736 1,617 31 2,459 Corporate debt securities 17 2 287 27 — 296 Municipal bonds 12 1 272 16 — 279 U.S. government bonds 16 2 466 26 — 412 Other debt securities — — 5 1 — 6 Total NDTF Investments $ 1,927 $ 26 $ 3,858 $ 1,687 $ 31 $ 3,528 Other Investments Cash and cash equivalents $ — $ — $ 16 $ — $ — $ 1 Total Other Investments $ — $ — $ 16 $ — $ — $ 1 Total Investments $ 1,927 $ 26 $ 3,874 $ 1,687 $ 31 $ 3,529
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 three and nine months ended September 30, 2021, and 2020, were as follows. Three Months Ended Nine Months Ended (in millions) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 FV-NI: Realized gains $ 9 $ 3 $ 76 $ 43 Realized losses 11 4 31 51 AFS: Realized gains 6 6 13 17 Realized losses 5 2 11 7
Duke Energy Florida
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI	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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value NDTF Cash and cash equivalents $ — $ — $ 12 $ — $ — $ 71 Equity securities 93 — 106 79 — 91 Corporate debt securities — — 65 — — — U.S. government bonds — 4 387 — — 474 Total NDTF Investments (a) $ 93 $ 4 $ 570 $ 79 $ — $ 636 Other Investments Cash and cash equivalents $ — $ — $ 1 $ — $ — $ 1 Municipal bonds 2 — 26 3 — 26 Total Other Investments $ 2 $ — $ 27 $ 3 $ — $ 27 Total Investments $ 95 $ 4 $ 597 $ 82 $ — $ 663 (a) During the nine months ended September 30, 2021, and the year ended December 31, 2020, Duke Energy Florida received reimbursements from the NDTF for costs related to ongoing decommissioning activity of Crystal River Unit 3.
Debt Securities, Available-for-sale	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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value NDTF Cash and cash equivalents $ — $ — $ 12 $ — $ — $ 71 Equity securities 93 — 106 79 — 91 Corporate debt securities — — 65 — — — U.S. government bonds — 4 387 — — 474 Total NDTF Investments (a) $ 93 $ 4 $ 570 $ 79 $ — $ 636 Other Investments Cash and cash equivalents $ — $ — $ 1 $ — $ — $ 1 Municipal bonds 2 — 26 3 — 26 Total Other Investments $ 2 $ — $ 27 $ 3 $ — $ 27 Total Investments $ 95 $ 4 $ 597 $ 82 $ — $ 663 (a) During the nine months ended September 30, 2021, and the year ended December 31, 2020, Duke Energy Florida received reimbursements from the NDTF for costs related to ongoing decommissioning activity of Crystal River Unit 3.
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 three and nine months ended September 30, 2021, and 2020, were as follows: Three Months Ended Nine Months Ended (in millions) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 FV-NI: Realized gains $ — $ — $ 1 $ 249 Realized losses — — 1 15 AFS: Realized gains 1 — 1 — Realized losses 1 — 1 —
Duke Energy Indiana
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI	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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value Investments Cash and cash equivalents $ — $ — $ 19 $ — $ — $ 1 Equity securities 56 — 90 58 — 97 Corporate debt securities — — 5 — — 3 Municipal bonds 1 1 36 1 — 38 U.S. government bonds — — 5 — — 4 Total Investments $ 57 $ 1 $ 155 $ 59 $ — $ 143
Debt Securities, Available-for-sale	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. September 30, 2021 December 31, 2020 Gross Gross Gross Gross Unrealized Unrealized Estimated Unrealized Unrealized Estimated Holding Holding Fair Holding Holding Fair (in millions) Gains Losses Value Gains Losses Value Investments Cash and cash equivalents $ — $ — $ 19 $ — $ — $ 1 Equity securities 56 — 90 58 — 97 Corporate debt securities — — 5 — — 3 Municipal bonds 1 1 36 1 — 38 U.S. government bonds — — 5 — — 4 Total Investments $ 57 $ 1 $ 155 $ 59 $ — $ 143

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2021
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 Condensed Consolidated Balance Sheets. Derivative amounts in the tables below for all Duke Energy Registrants exclude cash collateral, which is disclosed in Note 8. See Note 9 for additional information related to investments by major security type for the Duke Energy Registrants. September 30, 2021 (in millions) Total Fair Value Level 1 Level 2 Level 3 Not Categorized NDTF cash and cash equivalents $ 164 $ 164 $ — $ — $ — NDTF equity securities 6,754 6,705 — — 49 NDTF debt securities 2,943 998 1,945 — — Other equity securities 145 145 — — — Other debt securities 283 45 238 — — Other cash and cash equivalents 87 87 — — — Derivative assets 543 27 490 26 — Total assets 10,919 8,171 2,673 26 49 Derivative liabilities (415) (2) (256) (157) — Net assets (liabilities) $ 10,504 $ 8,169 $ 2,417 $ (131) $ 49 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
Reconciliation Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Unobservable Inputs	The following tables provide reconciliations of beginning and ending balances of assets and liabilities measured at fair value using Level 3 measurements. Derivatives (net) Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2021 2020 2021 2020 Balance at beginning of period $ (131) $ (92) $ (77) $ (102) Total pretax realized or unrealized losses included in comprehensive income (11) (102) (86) (102) Purchases, sales, issuances and settlements: Purchases — — 21 14 Settlements 4 (3) (4) (18) Total gains (losses) included on the Condensed Consolidated Balance Sheet 7 (6) 15 5 Balance at end of period $ (131) $ (203) $ (131) $ (203)
Quantitative Information Table - Level 3	The following tables include quantitative information about the Duke Energy Registrants' derivatives classified as Level 3. September 30, 2021 Weighted Fair Value Average Investment Type (in millions) Valuation Technique Unobservable Input Range Range Duke Energy Electricity contracts $ (157) RTO forward pricing Forward electricity curves – price per MWh $ 18.02 - $ 143.85 $ 38.43 Duke Energy Ohio FTRs 2 RTO auction pricing FTR price – per MWh 0.06 - 1.27 0.71 Duke Energy Indiana FTRs 24 RTO auction pricing FTR price – per MWh (1.11) - 8.55 1.61 Duke Energy Total Level 3 derivatives $ (131) 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)
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. September 30, 2021 December 31, 2020 (in millions) Book Value Fair Value Book Value Fair Value Duke Energy (a) $ 62,802 $ 69,381 $ 59,863 $ 69,292 Duke Energy Carolinas 12,975 14,964 12,218 14,917 Progress Energy 19,488 22,593 19,264 23,470 Duke Energy Progress 9,848 10,915 9,258 10,862 Duke Energy Florida 7,549 8,932 7,915 9,756 Duke Energy Ohio 3,092 3,517 3,089 3,650 Duke Energy Indiana 4,092 4,883 4,091 5,204 Piedmont 2,968 3,320 2,780 3,306 (a) Book value of long-term debt inc ludes $1.3 billion
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 Condensed Consolidated Balance Sheets. September 30, 2021 (in millions) Total Fair Value Level 1 Level 2 Not Categorized NDTF cash and cash equivalents $ 60 $ 60 $ — $ — NDTF equity securities 3,912 3,863 — 49 NDTF debt securities 1,461 359 1,102 — Derivative assets 271 — 271 — Total assets 5,704 4,282 1,373 49 Derivative liabilities (18) — (18) — Net assets $ 5,686 $ 4,282 $ 1,355 $ 49 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
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 tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets. September 30, 2021 December 31, 2020 (in millions) Total Fair Value Level 1 Level 2 Total Fair Value Level 1 Level 2 NDTF cash and cash equivalents $ 104 $ 104 $ — $ 147 $ 147 $ — NDTF equity securities 2,842 2,842 — 2,550 2,550 — NDTF debt securities 1,482 639 843 1,467 682 785 Other debt securities 26 — 26 26 — 26 Other cash and cash equivalents 18 18 — 106 106 — Derivative assets 215 — 215 33 — 33 Total assets 4,687 3,603 1,084 4,329 3,485 844 Derivative liabilities (12) — (12) (29) — (29) Net assets $ 4,675 $ 3,603 $ 1,072 $ 4,300 $ 3,485 $ 815
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 tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets. September 30, 2021 December 31, 2020 (in millions) Total Fair Value Level 1 Level 2 Total Fair Value Level 1 Level 2 NDTF cash and cash equivalents $ 92 $ 92 $ — $ 76 $ 76 $ — NDTF equity securities 2,736 2,736 — 2,459 2,459 — NDTF debt securities 1,030 278 752 993 237 756 Other cash and cash equivalents 16 16 — 1 1 — Derivative assets 215 — 215 33 — 33 Total assets 4,089 3,122 967 3,562 2,773 789 Derivative liabilities — — — (14) — (14) Net assets $ 4,089 $ 3,122 $ 967 $ 3,548 $ 2,773 $ 775
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 tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets. September 30, 2021 December 31, 2020 (in millions) Total Fair Value Level 1 Level 2 Total Fair Value Level 1 Level 2 NDTF cash and cash equivalents $ 12 $ 12 $ — $ 71 $ 71 $ — NDTF equity securities 106 106 — 91 91 — NDTF debt securities 452 361 91 474 445 29 Other debt securities 26 — 26 26 — 26 Other cash and cash equivalents 1 1 — 1 1 — Total assets 597 480 117 663 608 55 Derivative liabilities (12) — (12) — — — Net assets $ 585 $ 480 $ 105 $ 663 $ 608 $ 55
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 tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets. September 30, 2021 December 31, 2020 (in millions) Total Fair Value Level 1 Level 2 Level 3 Total Fair Value Level 1 Level 2 Level 3 Other equity securities $ 90 $ 90 $ — $ — $ 97 $ 97 $ — $ — Other debt securities 46 — 46 — 45 — 45 — Other cash and cash equivalents 19 19 — — 1 1 — — Derivative assets 36 12 — 24 6 — — 6 Total assets 191 121 46 24 149 98 45 6 Derivative liabilities (2) (2) — — (1) (1) — — Net assets $ 189 $ 119 $ 46 $ 24 $ 148 $ 97 $ 45 $ 6
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) Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2021 2020 2021 2020 Balance at beginning of period $ 22 $ 10 $ 6 $ 11 Purchases, sales, issuances and settlements: Purchases — — 18 10 Settlements (3) (3) (12) (13) Total gains included on the Condensed Consolidated Balance Sheet 5 1 12 — Balance at end of period $ 24 $ 8 $ 24 $ 8
Piedmont
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 Condensed Consolidated Balance Sheets. September 30, 2021 December 31, 2020 (in millions) Total Fair Value Level 1 Level 2 Total Fair Value Level 1 Level 2 Derivative assets $ 12 $ 12 $ — $ 1 $ 1 $ — Derivative liabilities (148) — (148) (122) — (122) Net (liabilities) assets $ (136) $ 12 $ (148) $ (121) $ 1 $ (122)
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) Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2021 2020 2021 2020 Balance at beginning of period $ — $ (105) $ — $ (117) Total (losses) gains and settlements — (6) — 6 Balance at end of period $ — $ (111) $ — $ (111)

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	9 Months Ended
	Sep. 30, 2021
VIE primary beneficiary
Variable Interest Entities [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 2023 Credit facility amount $ 350 $ 475 $ 350 $ 250 Amounts borrowed at September 30, 2021 350 475 350 250 Amounts borrowed at December 31, 2020 350 364 250 250 Restricted Receivables at September 30, 2021 535 915 532 443 Restricted Receivables at December 31, 2020 547 696 500 397
VIE not primary beneficiary
Variable Interest Entities [Line Items]
Schedule Of Variable Interest Entities	The following tables summarize the impact of non-consolidated VIEs on the Condensed Consolidated Balance Sheets. September 30, 2021 Duke Energy Duke Duke Pipeline Commercial Energy Energy (in millions) Investments Renewables Total Ohio Indiana Receivables from affiliated companies $ — $ — $ — $ 47 $ 77 Investments in equity method unconsolidated affiliates 15 465 480 — — Deferred tax asset 58 — 58 — — Total assets $ 73 $ 465 $ 538 $ 47 $ 77 Other current liabilities 61 3 64 — — Other noncurrent liabilities 63 3 66 — — Total liabilities $ 124 $ 6 $ 130 $ — $ — Net (liabilities) assets $ (51) $ 459 $ 408 $ 47 $ 77 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
DEFPF | VIE primary beneficiary
Variable Interest Entities [Line Items]
Schedule Of Variable Interest Entities	The following table summarizes the impact of DEFPF on Duke Energy Florida's Condensed Consolidated Balance Sheets. (in millions) September 30, 2021 December 31, 2020 Receivables of VIEs $ 6 $ 4 Regulatory Assets: Current 54 53 Current Assets: Other 17 39 Other Noncurrent Assets: Regulatory assets 896 937 Current Liabilities: Other 2 10 Current maturities of long-term debt 56 55 Long-Term Debt 946 1,002
Commercial Renewables | VIE primary beneficiary
Variable Interest Entities [Line Items]
Schedule Of Variable Interest Entities	The table below presents material balances reported on Duke Energy's Condensed Consolidated Balance Sheets related to Commercial Renewables VIEs. (in millions) September 30, 2021 December 31, 2020 Current Assets: Other $ 330 $ 257 Property, Plant and Equipment: Cost 7,315 6,394 Accumulated depreciation and amortization (1,414) (1,242) Other Noncurrent Assets: Other 110 67 Current maturities of long-term debt 165 167 Long-Term Debt 1,552 1,569 Other Noncurrent Liabilities: AROs 167 148 Other Noncurrent Liabilities: Other 341 316
CRC | VIE not primary beneficiary
Variable Interest Entities [Line Items]
Schedule Of Variable Interest Entities	The following table shows the gross and net receivables sold. Duke Energy Ohio Duke Energy Indiana (in millions) September 30, 2021 December 31, 2020 September 30, 2021 December 31, 2020 Receivables sold $ 218 $ 270 $ 328 $ 344 Less: Retained interests 47 83 77 110 Net receivables sold $ 171 $ 187 $ 251 $ 234 The following table shows sales and cash flows related to receivables sold. Duke Energy Ohio Duke Energy Indiana Three Months Ended Nine Months Ended Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, (in millions) 2021 2020 2021 2020 2021 2020 2021 2020 Sales Receivables sold $ 486 $ 462 $ 1,490 $ 1,428 $ 794 $ 717 $ 2,176 $ 1,947 Loss recognized on sale 2 2 7 8 4 3 10 9 Cash flows Cash proceeds from receivables sold $ 490 $ 449 $ 1,519 $ 1,439 $ 798 $ 689 $ 2,199 $ 1,941 Collection fees received — 1 1 1 — — 1 1 Return received on retained interests 1 1 3 3 1 1 4 4

Revenue (Tables)

Revenue (Tables)	9 Months Ended
	Sep. 30, 2021
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 $ 24 $ 107 $ 44 $ 45 $ 7 $ 51 $ 278 Duke Energy Progress 2 8 8 8 — — 26 Duke Energy Florida 22 99 36 37 7 51 252 Duke Energy Indiana — 1 9 14 15 25 64 Remaining Performance Obligations (in millions) 2021 2022 2023 2024 2025 Thereafter Total Piedmont $ 17 $ 67 $ 64 $ 61 $ 60 $ 336 $ 605
Disaggregation of Revenue	Disaggregated revenues are presented as follows: Three Months Ended September 30, 2021 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 $ 2,955 $ 892 $ 1,525 $ 619 $ 906 $ 223 $ 316 $ — General 1,873 685 826 400 426 119 240 — Industrial 861 360 264 195 69 35 202 — Wholesale 619 111 399 324 75 19 89 — Other revenues 252 72 198 118 80 17 23 — Total Electric Utilities and Infrastructure revenue from contracts with customers $ 6,560 $ 2,120 $ 3,212 $ 1,656 $ 1,556 $ 413 $ 870 $ — Gas Utilities and Infrastructure Residential $ 129 $ — $ — $ — $ — $ 62 $ — $ 66 Commercial 78 — — — — 24 — 58 Industrial 30 — — — — 3 — 26 Power Generation — — — — — — — 23 Other revenues 33 — — — — 4 — 9 Total Gas Utilities and Infrastructure revenue from contracts with customers $ 270 $ — $ — $ — $ — $ 93 $ — $ 182 Commercial Renewables Revenue from contracts with customers $ 56 $ — $ — $ — $ — $ — $ — $ — Other Revenue from contracts with customers $ 8 $ — $ — $ — $ — $ — $ — $ — Total revenue from contracts with customers $ 6,894 $ 2,120 $ 3,212 $ 1,656 $ 1,556 $ 506 $ 870 $ 182 Other revenue sources (a) $ 57 $ (16) $ 21 $ 11 $ 5 $ — $ 16 $ 13 Total revenues $ 6,951 $ 2,104 $ 3,233 $ 1,667 $ 1,561 $ 506 $ 886 $ 195 (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. Three Months Ended September 30, 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 $ 2,936 $ 883 $ 1,550 $ 616 $ 934 $ 213 $ 289 $ — General 1,804 664 805 384 421 119 212 — Industrial 797 342 245 179 66 35 175 — Wholesale 603 117 412 358 54 10 64 — Other revenues 238 62 167 75 92 23 22 — Total Electric Utilities and Infrastructure revenue from contracts with customers $ 6,378 $ 2,068 $ 3,179 $ 1,612 $ 1,567 $ 400 $ 762 $ — Gas Utilities and Infrastructure Residential $ 112 $ — $ — $ — $ — $ 55 $ — $ 57 Commercial 64 — — — — 20 — 44 Industrial 24 — — — — 3 — 22 Power Generation — — — — — — — 10 Other revenues 16 — — — — 3 — 11 Total Gas Utilities and Infrastructure revenue from contracts with customers $ 216 $ — $ — $ — $ — $ 81 $ — $ 144 Commercial Renewables Revenue from contracts with customers $ 57 $ — $ — $ — $ — $ — $ — $ — Other Revenue from contracts with customers $ 7 $ — $ — $ — $ — $ — $ — $ — Total revenue from contracts with customers $ 6,658 $ 2,068 $ 3,179 $ 1,612 $ 1,567 $ 481 $ 762 $ 144 Other revenue sources (a) $ 63 $ (10) $ 18 $ 14 $ — $ (8) $ (1) $ 18 Total revenues $ 6,721 $ 2,058 $ 3,197 $ 1,626 $ 1,567 $ 473 $ 761 $ 162 (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. Nine Months Ended September 30, 2021 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 $ 7,753 $ 2,368 $ 3,903 $ 1,657 $ 2,246 $ 589 $ 894 $ — General 4,805 1,685 2,170 1,036 1,134 329 619 — Industrial 2,228 872 700 500 200 99 558 — Wholesale 1,644 341 1,056 901 155 45 202 — Other revenues 712 208 509 272 237 61 64 — Total Electric Utilities and Infrastructure revenue from contracts with customers $ 17,142 $ 5,474 $ 8,338 $ 4,366 $ 3,972 $ 1,123 $ 2,337 $ — Gas Utilities and Infrastructure Residential $ 747 $ — $ — $ — $ — $ 241 $ — $ 505 Commercial 373 — — — — 99 — 273 Industrial 110 — — — — 14 — 96 Power Generation — — — — — — — 69 Other revenues 100 — — — — 21 — 34 Total Gas Utilities and Infrastructure revenue from contracts with customers $ 1,330 $ — $ — $ — $ — $ 375 $ — $ 977 Commercial Renewables Revenue from contracts with customers $ 163 $ — $ — $ — $ — $ — $ — $ — Other Revenue from contracts with customers $ 20 $ — $ — $ — $ — $ — $ — $ — Total Revenue from contracts with customers $ 18,655 $ 5,474 $ 8,338 $ 4,366 $ 3,972 $ 1,498 $ 2,337 $ 977 Other revenue sources (a) $ 204 $ (44) $ 79 $ 51 $ 15 $ (4) $ 29 $ 39 Total revenues $ 18,859 $ 5,430 $ 8,417 $ 4,417 $ 3,987 $ 1,494 $ 2,366 $ 1,016 (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. Nine Months Ended September 30, 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 $ 7,451 $ 2,316 $ 3,792 $ 1,578 $ 2,214 $ 558 $ 785 $ — General 4,691 1,720 2,080 1,001 1,079 336 554 — Industrial 2,148 871 673 487 186 103 502 — Wholesale 1,535 332 1,018 877 141 22 163 — Other revenues 713 184 476 208 268 62 63 — Total Electric Utilities and Infrastructure revenue from contracts with customers $ 16,538 $ 5,423 $ 8,039 $ 4,151 $ 3,888 $ 1,081 $ 2,067 $ — Gas Utilities and Infrastructure Residential $ 631 $ — $ — $ — $ — $ 214 $ — $ 417 Commercial 308 — — — — 86 — 222 Industrial 92 — — — — 12 — 80 Power Generation — — — — — — — 27 Other revenues 58 — — — — 12 — 46 Total Gas Utilities and Infrastructure revenue from contracts with customers $ 1,089 $ — $ — $ — $ — $ 324 $ — $ 792 Commercial Renewables Revenue from contracts with customers $ 170 $ — $ — $ — $ — $ — $ — $ — Other Revenue from contracts with customers $ 20 $ — $ — $ — $ — $ — $ — $ — Total Revenue from contracts with customers $ 17,817 $ 5,423 $ 8,039 $ 4,151 $ 3,888 $ 1,405 $ 2,067 $ 792 Other revenue sources (a) $ 274 $ (7) $ 78 $ 56 $ 9 $ (11) $ 3 $ 79 Total revenues $ 18,091 $ 5,416 $ 8,117 $ 4,207 $ 3,897 $ 1,394 $ 2,070 $ 871 (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.
Reserve for Credit Losses for Trade and Other Receivables	The following table presents the reserve for credit losses for trade and other receivables based on adoption of the new standard. Three Months Ended September 30, 2020 and 2021 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Balance at June 30, 2020 $ 102 $ 14 $ 29 $ 14 $ 14 $ 5 $ 3 $ 6 Write-Offs 12 (2) 15 13 2 — — — Credit Loss Expense (9) — (16) (15) — — — 3 Other Adjustments 28 10 9 9 — — — — Balance at September 30, 2020 $ 133 $ 22 $ 37 $ 21 $ 16 $ 5 $ 3 $ 9 Balance at June 30, 2021 $ 123 $ 42 $ 36 $ 21 $ 16 $ 4 $ 3 $ 13 Write-Offs (13) (3) (6) (3) (3) — — (4) Credit Loss Expense 11 4 6 3 3 — — 2 Other Adjustments 2 (1) — — — — — 4 Balance at September 30, 2021 $ 123 $ 42 $ 36 $ 21 $ 16 $ 4 $ 3 $ 15 Nine Months Ended September 30, 2020 and 2021 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 (7) (8) 8 8 — — — (5) Credit Loss Expense 24 9 2 (5) 8 1 — 7 Other Adjustments 35 10 9 9 — — — — Balance at September 30, 2020 $ 133 $ 22 $ 37 $ 21 $ 16 $ 5 $ 3 $ 9 Balance at December 31, 2020 $ 146 $ 23 $ 37 $ 23 $ 14 $ 4 $ 3 $ 12 Write-Offs (39) (10) (20) (11) (9) — — (7) Credit Loss Expense 40 20 19 9 10 — — 6 Other Adjustments (24) 9 — — 1 — — 4 Balance at September 30, 2021 $ 123 $ 42 $ 36 $ 21 $ 16 $ 4 $ 3 $ 15
Aging of Trade Receivables	The aging of trade receivables is presented in the table below. Duke Energy considers receivables greater than 30 days outstanding past due. September 30, 2021 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Unbilled Revenue (a)(b) $ 826 $ 308 $ 242 $ 125 $ 117 $ 5 $ 27 $ 7 0-30 days 2,201 689 910 521 388 65 41 80 30-60 days 194 74 63 37 26 7 5 6 60-90 days 57 30 14 6 8 1 1 3 90+ days 161 68 27 5 22 31 10 9 Deferred Payment Arrangements (c) 113 66 29 21 8 2 — 6 Trade and Other Receivables $ 3,552 $ 1,235 $ 1,285 $ 715 $ 569 $ 111 $ 84 $ 111 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 Revenue (a)(b) $ 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 (c) 215 96 80 52 28 — — 7 Trade and Other Receivables $ 3,299 $ 966 $ 1,166 $ 655 $ 509 $ 102 $ 58 $ 262 (a) Unbilled revenues are recognized by applying customer billing rates to the estimated volumes of energy or natural gas delivered but not yet billed and are included within Receivables and Receivables of VIEs on the Condensed Consolidated Balance Sheets. (b) 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 Condensed Consolidated Balance Sheets of Duke Energy Ohio and Duke Energy Indiana. See Note 11 for further information. These receivables for unbilled revenues are $64 million and $115 million for Duke Energy Ohio and Duke Energy Indiana, respectively, as of September 30, 2021, and $87 million and $134 million for Duke Energy Ohio and Duke Energy Indiana, respectively, as of December 31, 2020. (c) 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.

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2021
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. Three Months Ended September 30, Nine Months Ended September 30, (in millions, except per share amounts) 2021 2020 2021 2020 Net income available to Duke Energy common stockholders $ 1,366 $ 1,265 $ 3,070 $ 1,347 Accumulated preferred stock dividends adjustment 12 12 12 13 Less: Impact of participating securities 1 1 3 2 Income from continuing operations available to Duke Energy common stockholders $ 1,377 $ 1,276 $ 3,079 $ 1,358 Weighted average common shares outstanding – basic and diluted 769 735 769 735 EPS available to Duke Energy common stockholders Basic and diluted $ 1.79 $ 1.74 $ 4.00 $ 1.85 Potentially dilutive items excluded from the calculation (a) 2 2 2 2 Dividends declared per common share $ 0.985 $ 0.965 $ 2.915 $ 2.855 Dividends declared on Series A preferred stock per depositary share (b) $ 0.359 $ 0.359 $ 1.078 $ 1.078 Dividends declared on Series B preferred stock per share (c) $ 24.375 $ 24.375 $ 48.750 $ 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. (b) 5.75% Series A Cumulative Redeemable Perpetual Preferred Stock dividends are payable quarterly in arrears on the 16th day of March, June, September and December. The preferred stock has a $25 liquidation preference per depositary share. (c) 4.875% Series B Fixed-Rate Reset Cumulative Redeemable Perpetual Preferred Stock dividends are payable semiannually in arrears on the 16th day of March and September. The preferred stock has a $1,000 liquidation preference per share.

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	9 Months Ended
	Sep. 30, 2021
Qualified Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Components of Net Periodic Pension Costs	The following tables include the components of net periodic pension costs for qualified pension plans. Three Months Ended September 30, 2021 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Service cost $ 43 $ 14 $ 13 $ 7 $ 5 $ 2 $ 2 $ 1 Interest cost on projected benefit obligation 55 13 17 8 10 2 5 2 Expected return on plan assets (139) (36) (47) (21) (25) (7) (10) (5) Amortization of actuarial loss 33 7 10 5 5 2 3 2 Amortization of prior service credit (7) (2) (1) — (1) — — (1) Amortization of settlement charges 2 1 1 — — — — 1 Net periodic pension costs $ (13) $ (3) $ (7) $ (1) $ (6) $ (1) $ — $ — Three Months Ended September 30, 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 $ 41 $ 12 $ 12 $ 6 $ 5 $ 1 $ 2 $ 1 Interest cost on projected benefit obligation 67 16 21 10 12 4 6 2 Expected return on plan assets (143) (36) (48) (22) (25) (7) (11) (5) Amortization of actuarial loss 32 7 10 4 6 2 3 2 Amortization of prior service credit (8) (2) — — — — — (2) Amortization of settlement charges 11 6 5 5 1 — 1 1 Net periodic pension costs $ — $ 3 $ — $ 3 $ (1) $ — $ 1 $ (1) Nine Months Ended September 30, 2021 Duke Duke Duke Duke Duke Duke Energy Progress Energy Energy Energy Energy (in millions) Energy Carolinas Energy Progress Florida Ohio Indiana Piedmont Service cost $ 131 $ 42 $ 38 $ 22 $ 16 $ 4 $ 7 $ 4 Interest cost on projected benefit obligation 165 38 52 23 29 9 14 6 Expected return on plan assets (418) (106) (141) (63) (76) (21) (30) (15) Amortization of actuarial loss 100 22 29 14 15 5 10 7 Amortization of prior service credit (22) (6) (2) (1) (1) — (1) (6) Amortization of settlement charges 6 4 2 1 — — — 1 Net periodic pension costs $ (38) $ (6) $ (22) $ (4) $ (17) $ (3) $ — $ (3) Nine Months Ended September 30, 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 $ 124 $ 38 $ 36 $ 20 $ 16 $ 3 $ 6 $ 4 Interest cost on projected benefit obligation 202 47 64 29 35 12 17 7 Expected return on plan assets (429) (108) (143) (66) (76) (21) (32) (16) Amortization of actuarial loss 96 21 30 13 17 5 9 7 Amortization of prior service credit (24) (6) (2) (1) (1) — (1) (7) Amortization of settlement charges 16 8 6 6 1 — 1 1 Net periodic pension costs $ (15) $ — $ (9) $ 1 $ (8) $ (1) $ — $ (4)

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Summary of Effective Tax Rates	The ETRs from continuing operations for each of the Duke Energy Registrants are included in the following table. Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 Duke Energy 6.6 % 7.8 % 6.7 % (6.4) % Duke Energy Carolinas 2.9 % 12.0 % 3.6 % 13.6 % Progress Energy 12.9 % 10.4 % 11.5 % 13.4 % Duke Energy Progress 6.3 % 3.1 % 5.9 % 10.0 % Duke Energy Florida 19.1 % 21.4 % 19.1 % 20.3 % Duke Energy Ohio 13.4 % 16.7 % 15.3 % 16.6 % Duke Energy Indiana 15.8 % 19.6 % 16.3 % 19.4 % Piedmont 25.0 % 16.7 % 8.4 % 3.7 %

Organization and Basis of Pre_4

Organization and Basis of Presentation (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2020
Noncontrolling Interest [Line Items]
Other current liabilities	$ 2,239	$ 2,239		$ 2,936
Charges related to reduction in physical workspace	9	184
Impairment of assets and other charges
Noncontrolling Interest [Line Items]
Charges related to reduction in physical workspace	8	139
Operation, maintenance and other
Noncontrolling Interest [Line Items]
Charges related to reduction in physical workspace	1	28
Depreciation and amortization
Noncontrolling Interest [Line Items]
Charges related to reduction in physical workspace		17
Forecast
Noncontrolling Interest [Line Items]
Charges related to reduction in physical workspace			$ 200
ACP
Noncontrolling Interest [Line Items]
Other current liabilities	$ 36	$ 36		$ 936

Organization and Basis of Pre_5

Organization and Basis of Presentation (Schedule of Allocated Losses from Subsidiaries, Noncontrolling Interest) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Allocated losses to noncontrolling tax equity members utilizing the HLBV method	$ 119	$ 59	$ 217	$ 187
Allocated losses to noncontrolling members based on pro rata shares of ownership	10	11	30	21
Total Noncontrolling Interest Allocated Losses	$ 129	$ 70	$ 247	$ 208

Organization and Basis of Pre_6

Organization and Basis of Presentation (Schedule of Cash and Cash Equivalents) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Current Assets
Cash and cash equivalents	$ 548	$ 259
Other	194	194
Other Noncurrent Assets
Other	1	103
Total cash, cash equivalents and restricted cash	743	556	$ 600	$ 573
Progress Energy
Current Assets
Cash and cash equivalents	102	59
Other	17	39
Other Noncurrent Assets
Other		102
Total cash, cash equivalents and restricted cash	119	200	188	126
Duke Energy Florida
Current Assets
Cash and cash equivalents	40	11
Other	17	39
Other Noncurrent Assets
Total cash, cash equivalents and restricted cash	$ 57	$ 50	$ 35	$ 56

Organization and Basis of Pre_7

Organization and Basis of Presentation (Schedule of Inventory) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Public Utilities, Inventory [Line Items]
Inventory	$ 2,900	$ 3,167
Materials and supplies
Public Utilities, Inventory [Line Items]
Inventory	2,317	2,312
Coal
Public Utilities, Inventory [Line Items]
Inventory	312	561
Natural gas, oil and other fuel
Public Utilities, Inventory [Line Items]
Inventory	271	294
Duke Energy Carolinas
Public Utilities, Inventory [Line Items]
Inventory	969	1,010
Duke Energy Carolinas | Materials and supplies
Public Utilities, Inventory [Line Items]
Inventory	779	785
Duke Energy Carolinas | Coal
Public Utilities, Inventory [Line Items]
Inventory	152	186
Duke Energy Carolinas | Natural gas, oil and other fuel
Public Utilities, Inventory [Line Items]
Inventory	38	39
Progress Energy
Public Utilities, Inventory [Line Items]
Inventory	1,255	1,375
Progress Energy | Materials and supplies
Public Utilities, Inventory [Line Items]
Inventory	1,009	999
Progress Energy | Coal
Public Utilities, Inventory [Line Items]
Inventory	89	193
Progress Energy | Natural gas, oil and other fuel
Public Utilities, Inventory [Line Items]
Inventory	157	183
Duke Energy Progress
Public Utilities, Inventory [Line Items]
Inventory	815	911
Duke Energy Progress | Materials and supplies
Public Utilities, Inventory [Line Items]
Inventory	674	673
Duke Energy Progress | Coal
Public Utilities, Inventory [Line Items]
Inventory	45	131
Duke Energy Progress | Natural gas, oil and other fuel
Public Utilities, Inventory [Line Items]
Inventory	96	107
Duke Energy Florida
Public Utilities, Inventory [Line Items]
Inventory	439	464
Duke Energy Florida | Materials and supplies
Public Utilities, Inventory [Line Items]
Inventory	336	325
Duke Energy Florida | Coal
Public Utilities, Inventory [Line Items]
Inventory	43	63
Duke Energy Florida | Natural gas, oil and other fuel
Public Utilities, Inventory [Line Items]
Inventory	60	76
Duke Energy Ohio
Public Utilities, Inventory [Line Items]
Inventory	114	110
Duke Energy Ohio | Materials and supplies
Public Utilities, Inventory [Line Items]
Inventory	85	78
Duke Energy Ohio | Coal
Public Utilities, Inventory [Line Items]
Inventory	10	16
Duke Energy Ohio | Natural gas, oil and other fuel
Public Utilities, Inventory [Line Items]
Inventory	19	16
Duke Energy Indiana
Public Utilities, Inventory [Line Items]
Inventory	367	473
Duke Energy Indiana | Materials and supplies
Public Utilities, Inventory [Line Items]
Inventory	305	307
Duke Energy Indiana | Coal
Public Utilities, Inventory [Line Items]
Inventory	61	165
Duke Energy Indiana | Natural gas, oil and other fuel
Public Utilities, Inventory [Line Items]
Inventory	1	1
Piedmont
Public Utilities, Inventory [Line Items]
Inventory	68	68
Piedmont | Materials and supplies
Public Utilities, Inventory [Line Items]
Inventory	11	12
Piedmont | Natural gas, oil and other fuel
Public Utilities, Inventory [Line Items]
Inventory	$ 57	$ 56

Organization and Basis of Pre_8

Organization and Basis of Presentation (Schedule of New Accounting Pronouncements) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	$ 47,951	$ 51,240	$ 49,545	$ 49,184	$ 47,295	$ 46,611
Accounting Standards Update [Extensible List]	ASU 2016-13
Progress Energy
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	$ 15,593	16,882	16,942	16,241	16,429	16,221
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	4,108	3,293	2,687	2,471	3,260	2,707
Retained Earnings | Progress Energy
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	6,465	$ 7,743	$ 7,809	$ 7,109	$ 7,296	$ 7,090
Cumulative Change in Accounting Principle | Retained Earnings | Revision of Prior Period, Accounting Standards Update, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	120
Cumulative Change in Accounting Principle | Retained Earnings | Revision of Prior Period, Accounting Standards Update, Adjustment | Duke Energy Carolinas
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	16
Cumulative Change in Accounting Principle | Retained Earnings | Revision of Prior Period, Accounting Standards Update, Adjustment | Progress Energy
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	2
Cumulative Change in Accounting Principle | Retained Earnings | Revision of Prior Period, Accounting Standards Update, Adjustment | Duke Energy Progress
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	1
Cumulative Change in Accounting Principle | Retained Earnings | Revision of Prior Period, Accounting Standards Update, Adjustment | Duke Energy Florida
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	1
Cumulative Change in Accounting Principle | Retained Earnings | Revision of Prior Period, Accounting Standards Update, Adjustment | Piedmont
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings	$ 1

Business Segments (Narrative) (

Business Segments (Narrative) (Details) $ in Millions		Sep. 08, 2021USD ($)	Jan. 28, 2021USD ($)closing	Sep. 30, 2021USD ($)	Sep. 30, 2021USD ($)segment
Segment Reporting Information [Line Items]
Sale of noncontrolling interest	[1]			$ 999	$ 999
Noncontrolling Interests
Segment Reporting Information [Line Items]
Sale of noncontrolling interest	[1]			454	$ 454
Duke Energy Indiana | Noncontrolling Interests
Segment Reporting Information [Line Items]
Percentage sold			19.90%
Number of closings | closing			2
Value of sale of parent interest		$ 1,025	$ 2,000
Ownership interest sold		11.05%
Proceed of purchase price for exchange in interest		50.00%
Transaction costs		$ 27
Sale of noncontrolling interest		$ 545
Duke Energy Ohio
Segment Reporting Information [Line Items]
Number of reportable segments | segment					2
Wind and solar | Nonregulated
Segment Reporting Information [Line Items]
Renewable merchant plants				$ 206	$ 206
Joint owner ownership percentage				50.00%	50.00%
[1]	Relates to the sale of a noncontrolling interest in Duke Energy Indiana. See Note 2 for additional discussion.

Business Segments (Business Seg

Business Segments (Business Segment Data) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Segment Reporting Information [Line Items]
Operating revenues	$ 6,951	$ 6,721	$ 18,859	$ 18,091
Segment income (loss)	1,366	1,265	3,070	1,347
Less: Noncontrolling interests	129	70	247	208
Add: Preferred stock dividend	39	39	92	93
Net Income	1,276	1,234	2,915	1,232
Segment assets	167,007		167,007		$ 162,388
Equity in earnings (losses) of unconsolidated affiliates	22	(80)	14	(2,004)
Impairment of assets and other charges	211	28	342	36
Income (loss) before taxes	1,366	1,339	3,125	1,158
Nonregulated electric and other	193	192	573	574
Incurred costs	1,507	1,450	4,319	4,142
Duke Energy Carolinas
Segment Reporting Information [Line Items]
Operating revenues	2,104	2,058	5,430	5,416
Segment assets	46,221		46,221		45,048
Impairment of assets and other charges	163	20	238	22
Income (loss) before taxes	549	631	1,110	1,306
Incurred costs	471	402	1,347	1,218
Duke Energy Progress
Segment Reporting Information [Line Items]
Operating revenues	1,667	1,626	4,417	4,207
Segment assets	34,557		34,557		33,733
Impairment of assets and other charges	42	5	60	5
Income (loss) before taxes	400	357	850	790
Incurred costs	368	348	1,092	970
Piedmont
Segment Reporting Information [Line Items]
Operating revenues	195	162	1,016	871
Segment assets	9,024		9,024		8,615
Equity in earnings (losses) of unconsolidated affiliates			7	7
Impairment of assets and other charges	4	7	9	7
Income (loss) before taxes	(32)	(30)	191	161
Incurred costs	77	75	231	234
Duke Energy Ohio
Segment Reporting Information [Line Items]
Operating revenues	506	473	1,494	1,394
Segment income (loss)	58	70	188	201
Segment assets	10,505		10,505		$ 10,025
Impairment of assets and other charges			5
Income (loss) before taxes	67	84	222	241
Incurred costs	116	115	335	333
Impairment charges
Segment Reporting Information [Line Items]
Impairment of assets and other charges			139
Operations, maintenance and other
Segment Reporting Information [Line Items]
Impairment of assets and other charges			28
Depreciation and amortization
Segment Reporting Information [Line Items]
Impairment of assets and other charges			17
Electric Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	6,560	6,371	17,161	16,571
Gas Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	266	217	1,323	1,122
Gas Utilities and Infrastructure | Asset Impairment for Regulatory Action
Segment Reporting Information [Line Items]
Equity in earnings (losses) of unconsolidated affiliates			(19)
Commercial Renewables
Segment Reporting Information [Line Items]
Operating revenues	117	126	355	378
Total Reportable Segments
Segment Reporting Information [Line Items]
Operating revenues	6,943	6,714	18,839	18,071
Other
Segment Reporting Information [Line Items]
Operating revenues	8	7	20	20
Operating Segments | Electric Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	6,569	6,379	17,185	16,596
Segment income (loss)	1,425	1,381	3,180	2,839
Segment assets	141,565		141,565
Operating Segments | Electric Utilities and Infrastructure | Duke Energy Ohio
Segment Reporting Information [Line Items]
Operating revenues	413	394	1,119	1,070
Segment income (loss)	48	63	122	137
Segment assets	6,716		6,716
Operating Segments | Electric Utilities and Infrastructure | Impairment charges | Duke Energy Carolinas
Segment Reporting Information [Line Items]
Impairment of assets and other charges	160	19	160	19
Operating Segments | Electric Utilities and Infrastructure | Impairment charges | Duke Energy Progress
Segment Reporting Information [Line Items]
Impairment of assets and other charges	42		42
Operating Segments | Electric Utilities and Infrastructure | Impairment charges | Duke Energy Progress | ACP
Segment Reporting Information [Line Items]
Impairment of assets and other charges		5		5
Operating Segments | Electric Utilities and Infrastructure | Operations, maintenance and other | Duke Energy Carolinas
Segment Reporting Information [Line Items]
Income (loss) before taxes	5	8	5	8
Operating Segments | Electric Utilities and Infrastructure | Operations, maintenance and other | Duke Energy Progress
Segment Reporting Information [Line Items]
Income (loss) before taxes	7		7
Operating Segments | Electric Utilities and Infrastructure | Other income and expense | Duke Energy Carolinas
Segment Reporting Information [Line Items]
Income (loss) before taxes	77		77
Operating Segments | Electric Utilities and Infrastructure | Other income and expense | Duke Energy Progress
Segment Reporting Information [Line Items]
Income (loss) before taxes	34		34
Operating Segments | Electric Utilities and Infrastructure | Regulated electric operating revenues | Duke Energy Carolinas
Segment Reporting Information [Line Items]
Income (loss) before taxes	13		13
Operating Segments | Electric Utilities and Infrastructure | Regulated electric operating revenues | Duke Energy Progress
Segment Reporting Information [Line Items]
Income (loss) before taxes	15		15
Operating Segments | Electric Utilities and Infrastructure | Interest expense | Duke Energy Carolinas
Segment Reporting Information [Line Items]
Income (loss) before taxes	3		3
Operating Segments | Electric Utilities and Infrastructure | Interest expense | Duke Energy Progress
Segment Reporting Information [Line Items]
Income (loss) before taxes	5		5
Operating Segments | Gas Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	289	241	1,391	1,194
Segment income (loss)	(3)	(73)	259	(1,400)
Segment assets	14,692		14,692
Equity in earnings (losses) of unconsolidated affiliates	3	78		2,000
Operating Segments | Gas Utilities and Infrastructure | Duke Energy Ohio
Segment Reporting Information [Line Items]
Operating revenues	93	79	375	324
Segment income (loss)	11	9	77	68
Segment assets	3,783		3,783
Operating Segments | Gas Utilities and Infrastructure | Impairment charges
Segment Reporting Information [Line Items]
Impairment of assets and other charges	8
Operating Segments | Gas Utilities and Infrastructure | Impairment charges | Piedmont
Segment Reporting Information [Line Items]
Impairment of assets and other charges		7
Operating Segments | Gas Utilities and Infrastructure | Operations, maintenance and other
Segment Reporting Information [Line Items]
Income (loss) before taxes	1
Operating Segments | Commercial Renewables
Segment Reporting Information [Line Items]
Operating revenues	117	126	355	378
Segment income (loss)	78	60	152	207
Segment assets	7,037		7,037
Operating Segments | Commercial Renewables | Texas Storm Uri
Segment Reporting Information [Line Items]
Less: Noncontrolling interests			12
Equity in earnings (losses) of unconsolidated affiliates			29
Income (loss) before taxes			(35)
Nonregulated electric and other			8
Incurred costs			2
Operating Segments | Total Reportable Segments
Segment Reporting Information [Line Items]
Operating revenues	6,975	6,746	18,931	18,168
Segment income (loss)	1,500	1,368	3,591	1,646
Segment assets	163,294		163,294
Operating Segments | Total Reportable Segments | Duke Energy Ohio
Segment Reporting Information [Line Items]
Operating revenues	506	473	1,494	1,394
Segment income (loss)	59	72	199	205
Segment assets	10,499		10,499
Other | Operations, maintenance and other
Segment Reporting Information [Line Items]
Income (loss) before taxes				98
Other | Other
Segment Reporting Information [Line Items]
Operating revenues	28	24	81	73
Segment income (loss)	(134)	(103)	(521)	(299)
Segment assets	3,717		3,717
Other | Other | Duke Energy Ohio
Segment Reporting Information [Line Items]
Segment income (loss)	(1)	(2)	(11)	(4)
Segment assets	27		27
Eliminations
Segment Reporting Information [Line Items]
Operating revenues	(52)	(49)	(153)	(150)
Segment assets	(4)		(4)
Eliminations | Duke Energy Ohio
Segment Reporting Information [Line Items]
Segment assets	(21)		(21)
Eliminations | Electric Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	9	8	24	25
Eliminations | Gas Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	23	24	68	72
Eliminations | Total Reportable Segments
Segment Reporting Information [Line Items]
Operating revenues	32	32	92	97
Eliminations | Other
Segment Reporting Information [Line Items]
Operating revenues	$ 20	$ 17	$ 61	$ 53

Regulatory Matters (Duke Energy

Regulatory Matters (Duke Energy Carolinas and Duke Energy Progress) (Details) - USD ($) $ in Millions	Jan. 27, 2021	Jan. 22, 2021	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Public Utilities, General Disclosures [Line Items]
Impairment of assets and other charges			$ 211		$ 28	$ 342	$ 36
Duke Energy Carolinas
Public Utilities, General Disclosures [Line Items]
Impairment of assets and other charges			163		20	238	22
Duke Energy Carolinas | 20-year storm recovery bond
Public Utilities, General Disclosures [Line Items]
Facility term	20 years
Duke Energy Progress
Public Utilities, General Disclosures [Line Items]
Impairment of assets and other charges			$ 42		$ 5	$ 60	$ 5
Duke Energy Progress | 20-year storm recovery bond
Public Utilities, General Disclosures [Line Items]
Facility term	20 years
CCR Settlement Agreement | Duke Energy Carolinas and Duke Energy Progress
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%
CCR Settlement Agreement | Duke Energy Carolinas and Duke Energy Progress | NCUC
Public Utilities, General Disclosures [Line Items]
Public utilities, requested equity capital structure, percentage		48.00%
Public utilities, requested debt capital structure, percentage		52.00%
CCR Settlement Agreement | Duke Energy Carolinas
Public Utilities, General Disclosures [Line Items]
Impairment of assets and other charges				$ 454
Reversal of regulated electric operating revenues				50
CCR Settlement Agreement | Duke Energy Progress
Public Utilities, General Disclosures [Line Items]
Impairment of assets and other charges				494
Reversal of regulated electric operating revenues				$ 102
2020 North Carolina Storm Securitization Filings | Duke Energy Carolinas | NCUC | Storm costs
Public Utilities, General Disclosures [Line Items]
Regulatory assets	$ 287
2020 North Carolina Storm Securitization Filings | Duke Energy Progress | NCUC | Storm costs
Public Utilities, General Disclosures [Line Items]
Regulatory assets	$ 920

Regulatory Matters (Regulatory

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

Sep. 27, 2021contention

Jul. 28, 2021

Jun. 07, 2021

Jun. 06, 2021

May 21, 2021USD ($)

Mar. 31, 2021USD ($)

Sep. 30, 2019USD ($)

May 21, 2019USD ($)

Nov. 08, 2018USD ($)

Feb. 28, 2018

Aug. 25, 2017USD ($)

Sep. 30, 2021USD ($)

Sep. 30, 2020USD ($)

Sep. 30, 2021USD ($)

Sep. 30, 2020USD ($)

Public Utilities, General Disclosures [Line Items]

Impairment of assets and other charges

$ 211

$ 28

$ 342

$ 36

Other income and expenses, net

238

127

$ 493

310

Nuclear Regulatory Commission

Public Utilities, General Disclosures [Line Items]

Operating license extension

20 years

Duke Energy Carolinas

Public Utilities, General Disclosures [Line Items]

Impairment of assets and other charges

163

$ 20

$ 238

$ 22

Duke Energy Carolinas | NCUC | 2017 North Carolina Rate Case

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amount

$ 647

Requested return on equity, percent

9.90%

Public utilities, requested equity capital structure, percentage

52.00%

Public utilities, requested debt capital structure, percentage

48.00%

Duke Energy Carolinas | NCUC | 2019 North Carolina Rate Case

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amount

$ 291

Requested rate increase, percentage

6.00%

Requested rate increase (decrease), gross amount

$ 445

Requested rate increase (decrease), rider reduction

$ 154

Duke Energy Carolinas | NCUC | 2019 North Carolina Rate Case, additional Agreement and Stipulation of Partial Settlement

Public Utilities, General Disclosures [Line Items]

Approved return on equity percentage

9.60%

Public utilities, approved equity capital structure, percentage

52.00%

Public utilities, approved debt capital structure, percentage

48.00%

Approved rate increase, amount

$ 33

Duke Energy Carolinas | PSCSC | South Carolina Rate Case 2018

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amount

$ 168

Approved return on equity percentage

9.50%

Public utilities, approved equity capital structure, percentage

53.00%

Public utilities, approved debt capital structure, percentage

47.00%

Change in tax rate, deferred tax liability, income tax benefit

$ 66

Measurement period adjustment, income tax expense (benefit)

$ 45

Duke Energy Carolinas | PSCSC | South Carolina Rate Case 2018 | North Carolina Department of Revenue | State and local jurisdiction

Public Utilities, General Disclosures [Line Items]

Regulatory asset, amortization period

5 years

State and local taxes reduction amount

$ 17

Duke Energy Carolinas | Nuclear Regulatory Commission | Oconee Nuclear Station Subsequent License Renewal

Public Utilities, General Disclosures [Line Items]

Comment period

60 days

Number of contentions | contention

3

Duke Energy Carolinas | Nuclear Regulatory Commission | Oconee Nuclear Station Subsequent License Renewal | Oconee Nuclear Station

Public Utilities, General Disclosures [Line Items]

Operating license extension

20 years

Operating license

80 years

60 years

Duke Energy Carolinas | Grid Improvement | NCUC | 2019 North Carolina Rate Case, additional Agreement and Stipulation of Partial Settlement

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 800

Duke Energy Carolinas | Storm costs | NCUC | 2019 North Carolina Rate Case, additional Agreement and Stipulation of Partial Settlement

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 213

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

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 125

Regulatory asset, amortization period

12 years

Duke Energy Carolinas | Asset retirement obligations - coal ash | PSCSC | South Carolina Rate Case 2018

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 96

Regulatory asset, amortization period

5 years

Recovery costs denied

$ 115

Impairment of assets and other charges

160

160

Other income and expenses, net

$ 31

$ 31

Duke Energy Carolinas | Asset retirement obligations - unprotected EDIT, Property, Plant and Equipment | PSCSC | South Carolina Rate Case 2018

Public Utilities, General Disclosures [Line Items]

Regulatory asset, amortization period

20 years

Duke Energy Carolinas | Asset retirement obligations - unprotected EDIT | PSCSC | South Carolina Rate Case 2018

Public Utilities, General Disclosures [Line Items]

Regulatory asset, amortization period

5 years

Duke Energy Carolinas | Asset retirement obligations - deferred revenue | PSCSC | South Carolina Rate Case 2018

Public Utilities, General Disclosures [Line Items]

Regulatory asset, amortization period

5 years

Regulatory Matters (Regulator_2

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

May 21, 2021USD ($)

Apr. 16, 2021USD ($)

Oct. 16, 2020

Oct. 30, 2019USD ($)

Oct. 11, 2019

May 21, 2019USD ($)

Nov. 08, 2018USD ($)

Nov. 22, 2017

Jun. 01, 2017USD ($)

Sep. 30, 2021USD ($)

Sep. 30, 2020USD ($)

Sep. 30, 2021USD ($)

Sep. 30, 2020USD ($)

Jul. 27, 2020MW

Public Utilities, General Disclosures [Line Items]

Impairment of assets and other charges

$ 211

$ 28

$ 342

$ 36

Other income and expenses, net

238

127

493

310

Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Impairment of assets and other charges

42

$ 5

60

$ 5

Duke Energy Progress | Western Carolinas Modernization Plan

Public Utilities, General Disclosures [Line Items]

Generation capacity (MW) | MW

5

Duke Energy Progress | NCUC | 2017 North Carolina Rate Case

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amount

$ 477

Requested rate increase (decrease), amended amount

$ 420

Requested return on equity, percent

9.90%

Public utilities, requested equity capital structure, percentage

52.00%

Public utilities, requested debt capital structure, percentage

48.00%

Duke Energy Progress | NCUC | 2019 North Carolina Rate Case

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amount

$ 464

Requested rate increase, percentage

12.30%

Requested rate increase (decrease), gross amount

$ 586

Rider reduction

122

Requested rate increase (decrease), rider reduction

$ 120

Approved rate increase, amount

$ 178

Duke Energy Progress | NCUC | 2019 North Carolina Rate Case, additional Agreement and Stipulation of Partial Settlement

Public Utilities, General Disclosures [Line Items]

Approved return on equity percentage

9.60%

Public utilities, approved equity capital structure, percentage

52.00%

Public utilities, approved debt capital structure, percentage

48.00%

Duke Energy Progress | PSCSC | South Carolina Rate Case 2018

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amount

$ 59

Approved return on equity percentage

9.50%

Public utilities, approved equity capital structure, percentage

53.00%

Public utilities, approved debt capital structure, percentage

47.00%

Change in tax rate, deferred tax liability, income tax benefit

$ 17

Measurement period adjustment, income tax expense (benefit)

12

Duke Energy Progress | FERC | FERC Return on Equity Complaint, NCEMPA

Public Utilities, General Disclosures [Line Items]

Approved return on equity percentage

11.00%

Duke Energy Progress | FERC | FERC Return on Equity Complaint, NCEMC

Public Utilities, General Disclosures [Line Items]

Approved return on equity percentage

11.00%

Duke Energy Progress | State and local jurisdiction | North Carolina Department of Revenue | PSCSC | South Carolina Rate Case 2018

Public Utilities, General Disclosures [Line Items]

State and local taxes increase amount

12

Duke Energy Progress | Grid Improvement | NCUC | 2019 North Carolina Rate Case, additional Agreement and Stipulation of Partial Settlement

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 400

Duke Energy Progress | Storm costs | NCUC | 2019 North Carolina Rate Case, additional Agreement and Stipulation of Partial Settlement

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 714

Duke Energy Progress | Asset retirement obligations - coal ash | PSCSC | South Carolina Rate Case 2018

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 4

Regulatory asset, amortization period

5 years

Recovery costs denied

$ 65

Impairment of assets and other charges

42

42

Other income and expenses, net

$ 6

$ 6

Duke Energy Progress | Asset retirement obligations - unprotected EDIT, Property, Plant and Equipment | PSCSC | South Carolina Rate Case 2018

Public Utilities, General Disclosures [Line Items]

Regulatory asset, amortization period

20 years

Duke Energy Progress | Asset retirement obligations - unprotected EDIT | PSCSC | South Carolina Rate Case 2018

Public Utilities, General Disclosures [Line Items]

Regulatory asset, amortization period

5 years

Duke Energy Progress | Asset retirement obligations - deferred revenue | PSCSC | South Carolina Rate Case 2018

Public Utilities, General Disclosures [Line Items]

Regulatory asset, amortization period

3 years

Regulatory Matters (Regulator_3

Regulatory Matters (Regulatory Matters Narrative - Duke Energy Florida) (Details) - Duke Energy Florida	May 04, 2021USD ($)	Jul. 01, 2020USD ($)plantMW	Dec. 31, 2024USD ($)	Dec. 31, 2023USD ($)	Dec. 31, 2022USD ($)	Dec. 31, 2020USD ($)	Sep. 30, 2020USD ($)	May 19, 2020USD ($)	Dec. 19, 2019USD ($)	Nov. 22, 2019USD ($)	Apr. 30, 2019USD ($)
FPSC
Public Utilities, General Disclosures [Line Items]
Number of solar plants | plant		10
Generation capacity (MW) | MW		750
2021 Settlement | FPSC
Public Utilities, General Disclosures [Line Items]
Public utilities, approved equity capital structure, percentage	53.00%
Public utilities, approved debt capital structure, percentage	47.00%
Public utilities, basis points, increase, percentage	0.25%
Contract with customer, asset, after allowance for credit loss, noncurrent	$ 173,000,000
Future investment in infrastructure	$ 1,000,000,000
2021 Settlement | FPSC | US Treasury Securities
Public Utilities, General Disclosures [Line Items]
Public utilities, basis points, increase, percentage	0.50%
2021 Settlement | FPSC | Minimum
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage	8.85%
2021 Settlement | FPSC | Minimum | US Treasury Securities
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage	9.85%
2021 Settlement | FPSC | Maximum
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage	10.85%
2021 Settlement | FPSC | Maximum | US Treasury Securities
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage	10.10%
2021 Settlement | FPSC | Weighted Average
Public Utilities, General Disclosures [Line Items]
Approved return on equity percentage	9.85%
2021 Settlement | FPSC | Subsequent event
Public Utilities, General Disclosures [Line Items]
Approved rate increase, amount			$ 79,000,000	$ 49,000,000	$ 67,000,000
Hurricane Michael storm damage
Public Utilities, General Disclosures [Line Items]
Estimated storm costs - capital and operation maintenance						$ 80,000,000
Hurricane Michael storm damage | FPSC
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
Requested supplemental true-up								$ 3,000,000
Hurricane Dorian storm damage | FPSC
Public Utilities, General Disclosures [Line Items]
Estimated storm costs - capital and operation maintenance									$ 169,000,000
Actual storm costs - capital and operation maintenance							$ 145,000,000
Solar Project
Public Utilities, General Disclosures [Line Items]
Estimated cost of facilities		$ 1,000,000,000
Estimated cost of facilities period		4 years

Regulatory Matters (Regulator_4

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

Oct. 08, 2021USD ($)

Oct. 01, 2021USD ($)

Jun. 01, 2021USD ($)

Sep. 30, 2021USD ($)site

Dec. 31, 2020USD ($)

Nov. 18, 2020USD ($)order

Jul. 23, 2020USD ($)

Mar. 31, 2020USD ($)

Jan. 01, 2020plant

Nov. 21, 2019condition

Jul. 12, 2019USD ($)

Mar. 29, 2019USD ($)

Sep. 28, 2018USD ($)

Public Utilities, General Disclosures [Line Items]

Public utilities, property, plant and equipment, net

$ 110,236

$ 106,782

Duke Energy Ohio

Public Utilities, General Disclosures [Line Items]

Number of nuclear generating facilities eligible for funding | plant

2

Public utilities, property, plant and equipment, net

8,429

8,009

Duke Energy Ohio | Duke Energy Ohio Electric Base Rate Case | PUCO | Subsequent event

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amount

$ 55

Requested return on equity, percent

10.30%

Requested rate increase, percentage

3.30%

Duke Energy Ohio | Energy Efficiency Cost Recovery

Public Utilities, General Disclosures [Line Items]

Number of orders issued on application for rehearing | order

2

Shared savings cap

$ 8

Duke Energy Ohio | Natural Gas Pipeline extension | OPSB | Minimum

Public Utilities, General Disclosures [Line Items]

Estimated capital cost excluding AFUDC

185

Number of conditions on construction | condition

41

Duke Energy Ohio | Natural Gas Pipeline extension | OPSB | Maximum

Public Utilities, General Disclosures [Line Items]

Estimated capital cost excluding AFUDC

$ 205

Duke Energy Ohio | MGP Cost Recovery - 2009 Through 2012 | PUCO

Public Utilities, General Disclosures [Line Items]

Number of environmental remediation sites | site

2

Regulatory assets

$ 55

Duke Energy Ohio | MGP Cost Recovery - 2013 Through 2017 | PUCO

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 26

Duke Energy Ohio | MGP Cost Recovery - 2013 Through 2017 | PUCO | MGP Costs - regulatory disallowance

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 12

Duke Energy Ohio | MGP Cost Recovery - 2018 | PUCO

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 20

Duke Energy Ohio | MGP Cost Recovery - 2018 | PUCO | MGP Costs - regulatory disallowance

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 11

Duke Energy Ohio | MGP Cost Recovery - 2019 | PUCO

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 39

Duke Energy Ohio | MGP Cost Recovery - 2019 | PUCO | MGP Costs - regulatory disallowance

Public Utilities, General Disclosures [Line Items]

Regulatory assets

$ 4

Duke Energy Ohio | Midwest Propane Caverns

Public Utilities, General Disclosures [Line Items]

Public utilities, property, plant and equipment, net

$ 27

$ 27

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

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amount

$ 15

Requested rate increase, percentage

13.00%

Duke Energy Kentucky | Duke Energy Kentucky Gas Base Rate Case | KPSC | Subsequent event

Public Utilities, General Disclosures [Line Items]

Requested rate increase (decrease), amount

$ 9

Annual rate increase cap, percentage

5.00%

Base rate case-stay out period

4 years

Duke Energy Kentucky | Duke Energy Kentucky Gas Base Rate Case | KPSC | Subsequent event | Public Utilities, Natural Gas Base Rates

Public Utilities, General Disclosures [Line Items]

Requested rate increase, percentage

9.375%

Duke Energy Kentucky | Duke Energy Kentucky Gas Base Rate Case | KPSC | Subsequent event | Public Utilities, Natural Gas Riders

Public Utilities, General Disclosures [Line Items]

Requested rate increase, percentage

9.30%

Regulatory Matters (Regulator_5

Regulatory Matters (Regulatory Matters Narrative - Duke Energy Indiana) (Details) - Duke Energy Indiana - IURC - Indiana rate case 2019 - USD ($) $ in Millions	Jul. 28, 2021	Jun. 29, 2020	Dec. 04, 2019	Jul. 02, 2019	Dec. 31, 2020
Public Utilities, General Disclosures [Line Items]
Requested rate increase (decrease), amount				$ 395
Requested rate increase, percentage, net of tax			15.60%
Requested rate increase (decrease), amended amount			$ 396
Approved rate increase, amount		$ 146
Rate base					$ 10,200
Reduction of requested rate increase		$ 200
Reduction due to depreciation methodology		50.00%
Reduction due to approved return on equity		20.00%
Requested return on equity, percent		10.40%
Reduction due to earnings adjustments		20.00%
Estimated percentage of total rate increase, step one		75.00%
Estimated percentage of total rate increase, step two	25.00%
Approved return on equity percentage	9.70%	9.70%
Public utilities, approved equity capital structure, percentage	54.00%

Regulatory Matters (Regulator_6

Regulatory Matters (Regulatory Matters Narrative - Piedmont) (Details) - Piedmont - USD ($) $ in Millions	Sep. 07, 2021	Jul. 28, 2021	May 06, 2021	Mar. 22, 2021	Jul. 02, 2020	Dec. 31, 2020
2020 Tennessee Rate Case | TPUC
Public Utilities, General Disclosures [Line Items]
Requested rate increase (decrease), amount					$ 30	$ 26
Increase in annual revenue, percent					15.00%
Approved rate increase, amount			$ 16
Approved return on equity percentage			9.80%
2021 North Carolina Rate Case | NCUC
Public Utilities, General Disclosures [Line Items]
Requested rate increase (decrease), amount	$ 67			$ 109
Increase in annual revenue, percent				10.00%
Plants rolled into base rate				70.00%
Requested rate increase (decrease), amended amount		$ 97
Requested return on equity, percent	9.60%
Public utilities, requested equity capital structure, percentage	51.60%
Public utilities, requested debt capital structure, percentage	48.40%

Regulatory Matters (Other Regul

Regulatory Matters (Other Regulatory Matters) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Feb. 28, 2021	Dec. 31, 2020
Public Utilities, General Disclosures [Line Items]
Equity in (earnings) losses of unconsolidated affiliates		$ (22)	$ 80	$ (14)	$ 2,004
Other current liabilities		2,239		2,239			$ 2,936
Asset retirement obligations		673		673			718
ACP
Public Utilities, General Disclosures [Line Items]
Other current liabilities		36		36			$ 936
ACP | ACP
Public Utilities, General Disclosures [Line Items]
Equity in (earnings) losses of unconsolidated affiliates	$ 2,100
Other current liabilities		36		36
Other noncurrent liabilities		63		63
ACP | ACP | Current liabilities
Public Utilities, General Disclosures [Line Items]
Guarantor obligations settled						$ 855
Asset retirement obligations		$ 99		$ 99
ACP
Public Utilities, General Disclosures [Line Items]
Joint owner ownership percentage		47.00%		47.00%

Regulatory Matters (Schedule of

Regulatory Matters (Schedule of Net Carrying Value Of Facilities and Megawatt Capacity) (Details) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2021USD ($)MW	Dec. 31, 2034asset	Dec. 31, 2020USD ($)MW
Public Utilities, General Disclosures [Line Items]
Public utilities, property, plant and equipment, net	$ 110,236		$ 106,782
Duke Energy Carolinas
Public Utilities, General Disclosures [Line Items]
Public utilities, property, plant and equipment, net	33,920		33,187
Duke Energy Progress
Public Utilities, General Disclosures [Line Items]
Public utilities, property, plant and equipment, net	23,328		22,987
Duke Energy Florida
Public Utilities, General Disclosures [Line Items]
Public utilities, property, plant and equipment, net	17,461		16,563
Duke Energy Indiana
Public Utilities, General Disclosures [Line Items]
Public utilities, property, plant and equipment, net	$ 11,770		$ 11,721
Generation facilities to be retired
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	8,707
Public utilities, property, plant and equipment, net	$ 6,038
Generation facilities to be retired | Duke Energy Carolinas | Allen Steam Station Units 1-2
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	324
Public utilities, property, plant and equipment, net	$ 19
Generation facilities to be retired | Duke Energy Carolinas | Allen Steam Station Units 4-5
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	516
Public utilities, property, plant and equipment, net	$ 362
Generation facilities to be retired | Duke Energy Carolinas | Cliffside Unit 5
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	544
Public utilities, property, plant and equipment, net	$ 367
Generation facilities to be retired | Duke Energy Carolinas | Allen Steam Station 3
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW			270
Public utilities, property, plant and equipment, net			$ 26
Generation facilities to be retired | Duke Energy Progress | Mayo Unit 1
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	704
Public utilities, property, plant and equipment, net	$ 640
Generation facilities to be retired | Duke Energy Progress | Roxboro Units 3-4
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	1,392
Public utilities, property, plant and equipment, net	$ 465
Generation facilities to be retired | Duke Energy Florida | Crystal River Units 4-5
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	1,410
Public utilities, property, plant and equipment, net	$ 1,658
Generation facilities to be retired | Duke Energy Florida | Crystal River Units 4 and 5 | Forecast
Public Utilities, General Disclosures [Line Items]
Facilities retiring ahead of schedule | asset		2
Facilities retiring ahead of schedule, years ahead		8 years
Generation facilities to be retired | Duke Energy Indiana | Gibson Units 1-5
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	2,822
Public utilities, property, plant and equipment, net	$ 1,814
Generation facilities to be retired | Duke Energy Indiana | Cayuga Units 1-2
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	995
Public utilities, property, plant and equipment, net	$ 713
Generation facilities to be retired | Duke Energy Indiana | Gallagher Units 2 and 4
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW			280
Public utilities, property, plant and equipment, net			$ 102

Commitments and Contingencies_2

Commitments and Contingencies (Schedule of Environmental Loss Contingencies) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	$ 74	$ 75
Duke Energy Carolinas
Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	19	19
Progress Energy
Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	17	19
Duke Energy Progress
Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	6	6
Duke Energy Florida
Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	11	12
Duke Energy Ohio
Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	21	22
Duke Energy Indiana
Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	5	6
Piedmont
Environmental Matters Details [Line Items]
Reserves for Environmental Remediation	$ 12	$ 10

Commitments and Contingencies_3

Commitments and Contingencies (Narrative) (Details) $ in Millions	Jun. 16, 2021people	Sep. 30, 2021USD ($)claimcaseplant	Oct. 31, 2021USD ($)	Dec. 31, 2020USD ($)
Texas Storm Uri Tort Litigation
Loss Contingencies [Line Items]
Number of state court actions filed | case		30
Coal Ash Insurance Coverage Litigation
Loss Contingencies [Line Items]
Number of NC and SC Plants with Ash Basins | plant		15
Duke Energy Carolinas and Duke Energy Progress | Coal Ash Insurance Coverage Litigation | Subsequent event
Loss Contingencies [Line Items]
Proceeds from legal settlements			$ 418
Duke Energy Carolinas | Ruben Villano, et al. v. Duke Energy Carolinas, LLC | Pending Litigation
Loss Contingencies [Line Items]
Number of individuals | people	9
Number of survivors | people	4
Number of deceased individuals | people	5
Duke Energy Carolinas | Asbestos-related Injuries and Damages Claims
Loss Contingencies [Line Items]
Asbestos-related injuries and damages reserves		$ 508		$ 572
Reinsurance retention policy, excess retention, amount reinsured		697
Probable insurance recoveries		$ 644		704
Duke Energy Carolinas | Asbestos-related Injuries and Damages Claims | Non-malignant cases
Loss Contingencies [Line Items]
Loss contingency, pending claims, number | claim		74
Asbestos-related injuries and damages reserves		$ 15
Duke Energy Carolinas | Asbestos-related Injuries and Damages Claims | Malignant cases
Loss Contingencies [Line Items]
Loss contingency, pending claims, number | claim		58
Asbestos-related injuries and damages reserves		$ 21
Duke Energy and Duke Energy Carolinas | ASU 2016-13
Loss Contingencies [Line Items]
Reserve for credit losses for insurance receivables		$ 15		$ 15

Commitments and Contingencies_4

Commitments and Contingencies (Narrative 2) (Details) - Spent Nuclear Fuel Matters $ in Millions	Jun. 18, 2018USD ($)
Duke Energy Progress
Gain Contingencies [Line Items]
Gain contingency, unrecorded amount	$ 100
Duke Energy Florida
Gain Contingencies [Line Items]
Gain contingency, unrecorded amount	$ 200

Debt and Credit Facilities (Sum

Debt and Credit Facilities (Summary of Debt Issuances) (Details) - USD ($)	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Debt Instrument [Line Items]
Debt issuances	$ 5,950,000,000
Repayments of long-term debt	3,696,000,000	$ 3,468,000,000
Duke Energy (Parent)
Debt Instrument [Line Items]
Debt issuances	3,500,000,000
Repayments of long-term debt	1,750,000,000
Duke Energy Carolinas
Debt Instrument [Line Items]
Debt issuances	1,000,000,000
Repayments of long-term debt	616,000,000	457,000,000
Duke Energy Progress
Debt Instrument [Line Items]
Debt issuances	1,100,000,000
Repayments of long-term debt	605,000,000	$ 985,000,000
Piedmont
Debt Instrument [Line Items]
Debt issuances	350,000,000
Repayments of long-term debt	160,000,000
Unsecured Debt
Debt Instrument [Line Items]
Repayments of long-term debt	$ 160,000,000
Unsecured Debt | March 2021 Notes Due March 2031
Debt Instrument [Line Items]
Interest Rate	2.50%
Debt issuances	$ 350,000,000
Unsecured Debt | June 2021 Notes Due June 2023
Debt Instrument [Line Items]
Interest Rate	2.50%
Debt issuances	$ 500,000,000
Unsecured Debt | June 2021 Notes Due June 2031
Debt Instrument [Line Items]
Interest Rate	2.55%
Debt issuances	$ 1,000,000,000
Unsecured Debt | June 2021 Notes Due June 2041
Debt Instrument [Line Items]
Interest Rate	3.30%
Debt issuances	$ 750,000,000
Unsecured Debt | June 2021 Notes Due June 2051
Debt Instrument [Line Items]
Interest Rate	3.50%
Debt issuances	$ 750,000,000
Unsecured Debt | September 2021 Notes Due September 2081
Debt Instrument [Line Items]
Interest Rate	3.25%
Debt issuances	$ 500,000,000
Repayments of long-term debt	$ 500,000,000
Interest rate reset period	5 years
Unsecured Debt | Duke Energy (Parent) | June 2021 Notes Due June 2023
Debt Instrument [Line Items]
Debt issuances	$ 500,000,000
Unsecured Debt | Duke Energy (Parent) | June 2021 Notes Due June 2031
Debt Instrument [Line Items]
Debt issuances	1,000,000,000
Unsecured Debt | Duke Energy (Parent) | June 2021 Notes Due June 2041
Debt Instrument [Line Items]
Debt issuances	750,000,000
Unsecured Debt | Duke Energy (Parent) | June 2021 Notes Due June 2051
Debt Instrument [Line Items]
Debt issuances	750,000,000
Unsecured Debt | Duke Energy (Parent) | September 2021 Notes Due September 2081
Debt Instrument [Line Items]
Debt issuances	500,000,000
Unsecured Debt | Piedmont | March 2021 Notes Due March 2031
Debt Instrument [Line Items]
Debt issuances	$ 350,000,000
First Mortgage Bonds | April 2021 Notes Due April 2031
Debt Instrument [Line Items]
Interest Rate	2.55%
Debt issuances	$ 550,000,000
First Mortgage Bonds | April 2021 Notes Due April 2051
Debt Instrument [Line Items]
Interest Rate	3.45%
Debt issuances	$ 450,000,000
First Mortgage Bonds | August 2021 Notes Due August 2031
Debt Instrument [Line Items]
Interest Rate	2.00%
Debt issuances	$ 650,000,000
First Mortgage Bonds | August 2021 Notes Due August 2051
Debt Instrument [Line Items]
Interest Rate	2.90%
Debt issuances	$ 450,000,000
First Mortgage Bonds | Duke Energy Carolinas | April 2021 Notes Due April 2031
Debt Instrument [Line Items]
Debt issuances	550,000,000
First Mortgage Bonds | Duke Energy Carolinas | April 2021 Notes Due April 2051
Debt Instrument [Line Items]
Debt issuances	450,000,000
First Mortgage Bonds | Duke Energy Carolinas | Bonds maturing June 2021, 3.900% interest rate
Debt Instrument [Line Items]
Repayments of long-term debt	500,000,000
First Mortgage Bonds | Duke Energy Progress
Debt Instrument [Line Items]
Repayments of long-term debt	600,000,000
First Mortgage Bonds | Duke Energy Progress | August 2021 Notes Due August 2031
Debt Instrument [Line Items]
Debt issuances	650,000,000
First Mortgage Bonds | Duke Energy Progress | August 2021 Notes Due August 2051
Debt Instrument [Line Items]
Debt issuances	$ 450,000,000

Debt and Credit Facilities (S_2

Debt and Credit Facilities (Summary of Current Maturities of Long-term Debt) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Current maturities of long-term debt	$ 4,873	$ 4,238
Other debt securities
Debt Instrument [Line Items]
Current maturities of long-term debt	$ 520
Duke Energy (Parent) | Debt Maturing October 2021, 5.125% interest rate | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate	5.125%
Current maturities of long-term debt	$ 500
Duke Energy (Parent) | Debt Maturing March 2022, 3.227% interest rate | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate	3.227%
Current maturities of long-term debt	$ 300
Duke Energy (Parent) | Debt Maturing March 2022, 0.775%, floating interest rate | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate	0.764%
Current maturities of long-term debt	$ 300
Duke Energy (Parent) | Debt Maturing August 2022, 3.050% interest rate | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate	3.05%
Current maturities of long-term debt	$ 500
Duke Energy (Parent) | Debt Maturing August 2022, 2.400% interest rate | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate	2.40%
Current maturities of long-term debt	$ 500
Duke Energy Florida
Debt Instrument [Line Items]
Current maturities of long-term debt	$ 276	823
Duke Energy Florida | Debt Maturing November 2021, 0.391%, floating interest rate | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate	0.372%
Current maturities of long-term debt	$ 200
Duke Energy Progress
Debt Instrument [Line Items]
Current maturities of long-term debt	$ 1,207	603
Duke Energy Progress | Debt Maturing February 2022, 0.305%, floating interest rate | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate	0.305%
Current maturities of long-term debt	$ 700
Duke Energy Progress | Debt Maturing May 2022, 2.800%, interest rate | First Mortgage Bonds
Debt Instrument [Line Items]
Interest Rate	2.80%
Current maturities of long-term debt	$ 500
Progress Energy
Debt Instrument [Line Items]
Current maturities of long-term debt	$ 1,932	1,426
Progress Energy | Debt Maturing April 2022, 3.150% interest rate | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate	3.15%
Current maturities of long-term debt	$ 450
Duke Energy Indiana
Debt Instrument [Line Items]
Current maturities of long-term debt	$ 151	70
Duke Energy Indiana | Debt Maturing January 2022, 8.850% interest rate | First Mortgage Bonds
Debt Instrument [Line Items]
Interest Rate	8.85%
Current maturities of long-term debt	$ 53
Duke Energy Carolinas
Debt Instrument [Line Items]
Current maturities of long-term debt	$ 357	$ 506
Duke Energy Carolinas | Debt Maturing May 2022, 3.350% interest rate | First Mortgage Bonds
Debt Instrument [Line Items]
Interest Rate	3.35%
Current maturities of long-term debt	$ 350

Debt and Credit Facilities (Nar

Debt and Credit Facilities (Narrative) (Details) - Master Credit Facility - USD ($)	1 Months Ended
	Oct. 31, 2021	Sep. 30, 2021	Mar. 31, 2021
Debt Instrument [Line Items]
Facility size		$ 8,000,000,000	$ 8,000,000,000
Duke Energy Ohio
Debt Instrument [Line Items]
Facility size		775,000,000
Duke Energy Indiana
Debt Instrument [Line Items]
Facility size		$ 600,000,000
Subsequent event | Term Loan Facility | Duke Energy Ohio
Debt Instrument [Line Items]
Facility size	$ 100,000,000
Facility term	2 years
Subsequent event | Term Loan Facility | Duke Energy Kentucky
Debt Instrument [Line Items]
Facility size	$ 50,000,000
Facility term	2 years
Subsequent event | Term Loan Facility | Duke Energy Indiana
Debt Instrument [Line Items]
Facility size	$ 300,000,000
Facility term	2 years

Debt and Credit Facilities (Sch

Debt and Credit Facilities (Schedule of Line of Credit Facilities) (Details) - Master Credit Facility - USD ($)	Sep. 30, 2021	Mar. 31, 2021
Line of Credit Facility [Line Items]
Facility size	$ 8,000,000,000	$ 8,000,000,000
Commercial paper	(1,611,000,000)
Outstanding letters of credit	(31,000,000)
Tax-exempt bonds	(81,000,000)
Available capacity under the Master Credit Facility	6,277,000,000
Duke Energy Carolinas
Line of Credit Facility [Line Items]
Facility size	1,275,000,000
Commercial paper	(375,000,000)
Outstanding letters of credit	(4,000,000)
Available capacity under the Master Credit Facility	896,000,000
Duke Energy Progress
Line of Credit Facility [Line Items]
Facility size	1,150,000,000
Commercial paper	(253,000,000)
Outstanding letters of credit	(2,000,000)
Available capacity under the Master Credit Facility	895,000,000
Duke Energy Florida
Line of Credit Facility [Line Items]
Facility size	850,000,000
Commercial paper	(527,000,000)
Available capacity under the Master Credit Facility	323,000,000
Duke Energy Ohio
Line of Credit Facility [Line Items]
Facility size	775,000,000
Commercial paper	(419,000,000)
Available capacity under the Master Credit Facility	356,000,000
Duke Energy Indiana
Line of Credit Facility [Line Items]
Facility size	600,000,000
Commercial paper	(150,000,000)
Tax-exempt bonds	(81,000,000)
Available capacity under the Master Credit Facility	369,000,000
Piedmont
Line of Credit Facility [Line Items]
Facility size	700,000,000
Commercial paper	(276,000,000)
Available capacity under the Master Credit Facility	424,000,000
Duke Energy (Parent) | Proceeds loaned to subsidiary registrants
Line of Credit Facility [Line Items]
Commercial paper	(625,000,000)
Duke Energy (Parent) | Duke Energy (Parent)
Line of Credit Facility [Line Items]
Facility size	2,650,000,000
Commercial paper	389,000,000
Outstanding letters of credit	(25,000,000)
Available capacity under the Master Credit Facility	$ 3,014,000,000

Debt and Credit Facilities (S_3

Debt and Credit Facilities (Schedule of Other Credit Facilities) (Details) - Master Credit Facility - USD ($)	9 Months Ended
	Sep. 30, 2021	Mar. 31, 2021
Line of Credit Facility [Line Items]
Facility size	$ 8,000,000,000	$ 8,000,000,000
Duke Energy (Parent) Three-Year Revolving Credit Facility | Duke Energy (Parent)
Line of Credit Facility [Line Items]
Facility size	1,000,000,000
Amount drawn	$ 500,000,000
Facility term	3 years

Goodwill (Rollforward of Goodwi

Goodwill (Rollforward of Goodwill) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Goodwill [Line Items]
Goodwill balance	$ 19,425	$ 19,425
Accumulated impairment charges	(122)	(122)
Goodwill, adjusted for accumulated impairment charges	19,303	19,303
Electric Utilities and Infrastructure
Goodwill [Line Items]
Goodwill balance	17,379	17,379
Goodwill, adjusted for accumulated impairment charges	17,379	17,379
Gas Utilities and Infrastructure
Goodwill [Line Items]
Goodwill balance	1,924	1,924
Goodwill, adjusted for accumulated impairment charges	1,924	1,924
Commercial Renewables
Goodwill [Line Items]
Goodwill balance	122	122
Accumulated impairment charges	$ (122)	$ (122)

Goodwill (Narrative) (Details)

Goodwill (Narrative) (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Goodwill [Line Items]
Goodwill	$ 19,303,000,000	$ 19,303,000,000
Accumulated impairment charges	122,000,000	122,000,000
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
Accumulated impairment charges	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]
Accumulated impairment charges	0	0
Piedmont
Goodwill [Line Items]
Goodwill	49,000,000	49,000,000
Piedmont | Gas Utilities and Infrastructure
Goodwill [Line Items]
Accumulated impairment charges	$ 0	$ 0

Related Party Transactions (Oth

Related Party Transactions (Other Revenue and Expense) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
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	$ 207	$ 198	$ 653	$ 528
Duke Energy Carolinas | Indemnification coverages | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	6	5	18	15
Duke Energy Carolinas | JDA | Duke Energy Progress
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	68	28	133	72
Related party transaction, other revenues from transactions with related party	6	6	32	16
Duke Energy Carolinas | Intercompany natural gas purchases and sales | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	14	10	43	26
Progress Energy | Corporate governance and shared service expenses | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	201	185	615	520
Progress Energy | Indemnification coverages | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	10	9	31	27
Progress Energy | JDA | Duke Energy Carolinas
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	6	6	32	16
Related party transaction, other revenues from transactions with related party	68	28	133	72
Progress Energy | Intercompany natural gas purchases and sales | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	19	18	56	56
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	121	113	367	301
Duke Energy Progress | Indemnification coverages | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	4	4	14	13
Duke Energy Progress | JDA | Duke Energy Carolinas
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	6	6	32	16
Related party transaction, other revenues from transactions with related party	68	28	133	72
Duke Energy Progress | Intercompany natural gas purchases and sales | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	19	18	56	56
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	80	72	248	219
Duke Energy Florida | Indemnification coverages | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	6	5	17	14
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	79	80	237	241
Duke Energy Ohio | Indemnification coverages | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	1	1	3	3
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	96	102	302	300
Duke Energy Indiana | Indemnification coverages | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	2	2	6	6
Piedmont | Corporate governance and shared service expenses | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	32	31	101	102
Piedmont | Indemnification coverages | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	1	1	3	2
Piedmont | Intercompany natural gas purchases and sales | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, other revenues from transactions with related party	33	28	99	82
Piedmont | Natural gas storage and transportation costs | Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	$ 6	$ 6	$ 17	$ 17

Related Party Transactions (Int

Related Party Transactions (Intercompany Income Taxes) (Details) - Affiliated Entity - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Duke Energy Carolinas
Related Party Transaction [Line Items]
Intercompany income tax payable	$ 133	$ 31
Progress Energy
Related Party Transaction [Line Items]
Intercompany income tax receivable	36
Intercompany income tax payable		33
Duke Energy Progress
Related Party Transaction [Line Items]
Intercompany income tax payable	51	46
Duke Energy Florida
Related Party Transaction [Line Items]
Intercompany income tax receivable	8
Intercompany income tax payable		35
Duke Energy Ohio
Related Party Transaction [Line Items]
Intercompany income tax receivable	1
Intercompany income tax payable		2
Duke Energy Indiana
Related Party Transaction [Line Items]
Intercompany income tax receivable		9
Intercompany income tax payable	17
Piedmont
Related Party Transaction [Line Items]
Intercompany income tax receivable	$ 14	$ 10

Derivatives and Hedging (Notion

Derivatives and Hedging (Notional Amounts of Derivative Instruments) (Details) Mcf in Millions, $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2021USD ($)GWhMcf	Dec. 31, 2020USD ($)GWhMcf
Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 3,465	$ 1,809
Commodity contracts | Cash flow hedges
Derivative [Line Items]
Notional amount, energy measure (in gigawatt-hours) | GWh	10,159	22,048
Commodity contracts | Electricity (GWh)(a)
Derivative [Line Items]
Notional amount, energy measure (in gigawatt-hours) | GWh	29,044	35,409
Commodity contracts | Natural gas (millions of dekatherms)
Derivative [Line Items]
Notional amount, volume (in millions of dekatherms) | Mcf	772	678
Designated contracts | Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 2,094	$ 632
Designated contracts | Interest Rate Contracts | VIE primary beneficiary
Derivative [Line Items]
Notional amount	594	632
Undesignated contracts | Interest Rate Contracts
Derivative [Line Items]
Notional amount	1,371	1,177
Undesignated contracts | Interest Rate Contracts | VIE primary beneficiary
Derivative [Line Items]
Notional amount	94
Duke Energy Carolinas | Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 350	$ 400
Duke Energy Carolinas | Commodity contracts | Natural gas (millions of dekatherms)
Derivative [Line Items]
Notional amount, volume (in millions of dekatherms) | Mcf	230	145
Duke Energy Carolinas | Undesignated contracts | Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 350	$ 400
Progress Energy | Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 900	$ 750
Progress Energy | Commodity contracts | Natural gas (millions of dekatherms)
Derivative [Line Items]
Notional amount, volume (in millions of dekatherms) | Mcf	190	158
Progress Energy | Undesignated contracts | Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 900	$ 750
Duke Energy Progress | Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 400	$ 750
Duke Energy Progress | Commodity contracts | Natural gas (millions of dekatherms)
Derivative [Line Items]
Notional amount, volume (in millions of dekatherms) | Mcf	190	158
Duke Energy Progress | Undesignated contracts | Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 400	$ 750
Duke Energy Florida | Interest Rate Contracts
Derivative [Line Items]
Notional amount	500
Duke Energy Florida | Undesignated contracts | Interest Rate Contracts
Derivative [Line Items]
Notional amount	500
Duke Energy Ohio | Interest Rate 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	3,004	2,559
Duke Energy Ohio | Undesignated contracts | Interest Rate Contracts
Derivative [Line Items]
Notional amount	$ 27	$ 27
Duke Energy Indiana | Commodity contracts | Electricity (GWh)(a)
Derivative [Line Items]
Notional amount, energy measure (in gigawatt-hours) | GWh	15,881	10,802
Duke Energy Indiana | Commodity contracts | Natural gas (millions of dekatherms)
Derivative [Line Items]
Notional amount, volume (in millions of dekatherms) | Mcf	7	2
Piedmont | Commodity contracts | Natural gas (millions of dekatherms)
Derivative [Line Items]
Notional amount, volume (in millions of dekatherms) | Mcf	345	373

Derivatives and Hedging (Locati

Derivatives and Hedging (Location and Fair Value Amounts of Derivatives Reflected in the Condensed Consolidated Balance Sheets) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	$ 543	$ 61
Location and fair value amounts of derivatives (Liability)	415	324
Current assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	363	48
Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	180	13
Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	134	64
Noncurrent liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	281	260
Commodity Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	536	43
Location and fair value amounts of derivatives (Liability)	318	251
Interest Rate Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	7	18
Location and fair value amounts of derivatives (Liability)	97	73
Not Designated as Hedging Instruments | Commodity Contracts | Current assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	359	30
Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	177	13
Not Designated as Hedging Instruments | Commodity Contracts | Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	33	30
Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	128	137
Not Designated as Hedging Instruments | Interest Rate Contracts | Current assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	2	18
Not Designated as Hedging Instruments | Interest Rate Contracts | Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	19	5
Not Designated as Hedging Instruments | Interest Rate Contracts | Noncurrent liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	4	5
Designated as Hedging Instruments | Commodity Contracts | Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	37	14
Designated as Hedging Instruments | Commodity Contracts | Noncurrent liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	120	70
Designated as Hedging Instruments | Interest Rate Contracts | Current assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	2
Designated as Hedging Instruments | Interest Rate Contracts | Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	3
Designated as Hedging Instruments | Interest Rate Contracts | Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	45	15
Designated as Hedging Instruments | Interest Rate Contracts | Noncurrent liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	29	48
Duke Energy Carolinas
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	271	20
Location and fair value amounts of derivatives (Liability)	18	20
Duke Energy Carolinas | Current assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	171	14
Duke Energy Carolinas | Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	100	6
Duke Energy Carolinas | Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	18	17
Duke Energy Carolinas | Noncurrent liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)		3
Duke Energy Carolinas | Commodity Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	271	20
Location and fair value amounts of derivatives (Liability)	12	16
Duke Energy Carolinas | Interest Rate Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	6	4
Duke Energy Carolinas | Not Designated as Hedging Instruments | Commodity Contracts | Current assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	171	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 (Asset)	100	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 (Liability)	12	13
Duke Energy Carolinas | Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)		3
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 (Liability)	6	4
Progress Energy
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	215	33
Location and fair value amounts of derivatives (Liability)	12	29
Progress Energy | Current assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	137	27
Progress Energy | Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	78	6
Progress Energy | Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	12	2
Progress Energy | Noncurrent liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)		27
Progress Energy | Commodity Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	213	15
Location and fair value amounts of derivatives (Liability)		29
Progress Energy | Interest Rate Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	2	18
Location and fair value amounts of derivatives (Liability)	12
Progress Energy | Not Designated as Hedging Instruments | Commodity Contracts | Current assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	135	9
Progress Energy | Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	78	6
Progress Energy | Not Designated as Hedging Instruments | Commodity Contracts | Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)		2
Progress Energy | Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)		27
Progress Energy | Not Designated as Hedging Instruments | Interest Rate Contracts | Current assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	2	18
Progress Energy | Not Designated as Hedging Instruments | Interest Rate Contracts | Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	12
Duke Energy Progress
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	215	33
Location and fair value amounts of derivatives (Liability)		14
Duke Energy Progress | Current assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	137	27
Duke Energy Progress | Noncurrent assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	78	6
Duke Energy Progress | Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)		2
Duke Energy Progress | Noncurrent liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)		12
Duke Energy Progress | Commodity Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	213	15
Location and fair value amounts of derivatives (Liability)		14
Duke Energy Progress | Interest Rate Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	2	18
Duke Energy Progress | Not Designated as Hedging Instruments | Commodity Contracts | Current assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	135	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 (Asset)	78	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 (Liability)		2
Duke Energy Progress | Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)		12
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 (Asset)	2	18
Duke Energy Florida
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	12
Duke Energy Florida | Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	12
Duke Energy Florida | Interest Rate Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	12
Duke Energy Florida | Not Designated as Hedging Instruments | Interest Rate Contracts | Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	12
Duke Energy Ohio
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	4	1
Location and fair value amounts of derivatives (Liability)	5	6
Duke Energy Ohio | Current assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	4	1
Duke Energy Ohio | Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	1	1
Duke Energy Ohio | Noncurrent liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	4	5
Duke Energy Ohio | Commodity Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	4	1
Duke Energy Ohio | Interest Rate Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	5	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 (Asset)	4	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 (Liability)	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 (Liability)	4	5
Duke Energy Indiana
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	36	6
Location and fair value amounts of derivatives (Liability)	2	1
Duke Energy Indiana | Current assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	36	6
Duke Energy Indiana | Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	2	1
Duke Energy Indiana | Commodity Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	36	6
Location and fair value amounts of derivatives (Liability)	2	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 (Asset)	36	6
Duke Energy Indiana | Not Designated as Hedging Instruments | Commodity Contracts | Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	2	1
Piedmont
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	12	1
Location and fair value amounts of derivatives (Liability)	148	122
Piedmont | Current assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	12	1
Piedmont | Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	20	15
Piedmont | Noncurrent liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	128	107
Piedmont | Commodity Contracts
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	12	1
Location and fair value amounts of derivatives (Liability)	148	122
Piedmont | Not Designated as Hedging Instruments | Commodity Contracts | Current assets
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Asset)	12	1
Piedmont | Not Designated as Hedging Instruments | Commodity Contracts | Current liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	20	15
Piedmont | Not Designated as Hedging Instruments | Commodity Contracts | Noncurrent liabilities
Derivatives, Fair Value [Line Items]
Location and fair value amounts of derivatives (Liability)	$ 128	$ 107

Derivatives and Hedging (Schedu

Derivatives and Hedging (Schedule of Offsetting Assets) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	$ 543	$ 61
Net amounts recognized on the Condensed Consolidated Balance Sheet	543	61
Current assets
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	363	48
Gross amounts offset	(143)	(3)
Net amounts recognized on the Condensed Consolidated Balance Sheet	220	45
Noncurrent assets
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	180	13
Gross amounts offset	(71)	(5)
Net amounts recognized on the Condensed Consolidated Balance Sheet	109	8
Duke Energy Carolinas
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	271	20
Net amounts recognized on the Condensed Consolidated Balance Sheet	271	20
Duke Energy Carolinas | Current assets
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	171	14
Gross amounts offset	(87)	(2)
Net amounts recognized on the Condensed Consolidated Balance Sheet	84	12
Duke Energy Carolinas | Noncurrent assets
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	100	6
Gross amounts offset	(45)	(1)
Net amounts recognized on the Condensed Consolidated Balance Sheet	55	5
Progress Energy
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	215	33
Net amounts recognized on the Condensed Consolidated Balance Sheet	215	33
Progress Energy | Current assets
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	137	27
Gross amounts offset	(56)	(2)
Net amounts recognized on the Condensed Consolidated Balance Sheet	81	25
Progress Energy | Noncurrent assets
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	78	6
Gross amounts offset	(26)	(4)
Net amounts recognized on the Condensed Consolidated Balance Sheet	52	2
Duke Energy Progress
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	215	33
Net amounts recognized on the Condensed Consolidated Balance Sheet	215	33
Duke Energy Progress | Current assets
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	137	27
Gross amounts offset	(56)	(2)
Net amounts recognized on the Condensed Consolidated Balance Sheet	81	25
Duke Energy Progress | Noncurrent assets
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	78	6
Gross amounts offset	(26)	(4)
Net amounts recognized on the Condensed Consolidated Balance Sheet	52	2
Duke Energy Ohio
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	4	1
Duke Energy Ohio | Current assets
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	4	1
Net amounts recognized on the Condensed Consolidated Balance Sheet	4	1
Duke Energy Indiana
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	36	6
Net amounts recognized on the Condensed Consolidated Balance Sheet	36	6
Duke Energy Indiana | Current assets
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	36	6
Net amounts recognized on the Condensed Consolidated Balance Sheet	36	6
Piedmont
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	12	1
Net amounts recognized on the Condensed Consolidated Balance Sheet	12	1
Piedmont | Current assets
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	12	1
Net amounts recognized on the Condensed Consolidated Balance Sheet	$ 12	$ 1

Derivatives and Hedging (Sche_2

Derivatives and Hedging (Schedule of Offsetting Liabilities) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	$ 415	$ 324
Net amounts recognized on the Condensed Consolidated Balance Sheet	415	324
Current liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	134	64
Gross amounts offset		(3)
Net amounts recognized on the Condensed Consolidated Balance Sheet	134	61
Noncurrent liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	281	260
Gross amounts offset		(5)
Net amounts recognized on the Condensed Consolidated Balance Sheet	281	255
Duke Energy Carolinas
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	18	20
Net amounts recognized on the Condensed Consolidated Balance Sheet	18	20
Duke Energy Carolinas | Current liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	18	17
Gross amounts offset		(2)
Net amounts recognized on the Condensed Consolidated Balance Sheet	18	15
Duke Energy Carolinas | Noncurrent liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized		3
Gross amounts offset		(1)
Net amounts recognized on the Condensed Consolidated Balance Sheet		2
Progress Energy
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	12	29
Net amounts recognized on the Condensed Consolidated Balance Sheet	12	29
Progress Energy | Current liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	12	2
Gross amounts offset		(2)
Net amounts recognized on the Condensed Consolidated Balance Sheet	12
Progress Energy | Noncurrent liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized		27
Gross amounts offset		(4)
Net amounts recognized on the Condensed Consolidated Balance Sheet		23
Duke Energy Progress
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized		14
Net amounts recognized on the Condensed Consolidated Balance Sheet		14
Duke Energy Progress | Current liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized		2
Gross amounts offset		(2)
Duke Energy Progress | Noncurrent liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized		12
Gross amounts offset		(4)
Net amounts recognized on the Condensed Consolidated Balance Sheet		8
Duke Energy Florida
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	12
Net amounts recognized on the Condensed Consolidated Balance Sheet	12
Duke Energy Florida | Current liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	12
Net amounts recognized on the Condensed Consolidated Balance Sheet	12
Duke Energy Ohio
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	5	6
Duke Energy Ohio | Current liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	1	1
Net amounts recognized on the Condensed Consolidated Balance Sheet	1	1
Duke Energy Ohio | Noncurrent liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	4	5
Net amounts recognized on the Condensed Consolidated Balance Sheet	4	5
Duke Energy Indiana
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	2	1
Net amounts recognized on the Condensed Consolidated Balance Sheet	2	1
Duke Energy Indiana | Current liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	2	1
Net amounts recognized on the Condensed Consolidated Balance Sheet	2	1
Piedmont
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	148	122
Net amounts recognized on the Condensed Consolidated Balance Sheet	148	122
Piedmont | Current liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	20	15
Net amounts recognized on the Condensed Consolidated Balance Sheet	20	15
Piedmont | Noncurrent liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	128	107
Net amounts recognized on the Condensed Consolidated Balance Sheet	$ 128	$ 107

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	Sep. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale
Estimated Fair Value	$ 3,226
Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract]
Unrealized Holding Gains	4,885	$ 4,387
Unrealized Holding Losses	52	55
Estimated Fair Value	10,376	9,687
Duke Energy Carolinas
Debt Securities, Available-for-sale
Estimated Fair Value	1,461
Progress Energy
Debt Securities, Available-for-sale
Estimated Fair Value	1,508
Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract]
Unrealized Holding Gains	2,022	1,769
Unrealized Holding Losses	30	31
Estimated Fair Value	4,472	4,296
Duke Energy Progress
Debt Securities, Available-for-sale
Estimated Fair Value	1,030
Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract]
Unrealized Holding Gains	1,927	1,687
Unrealized Holding Losses	26	31
Estimated Fair Value	3,874	3,529
Duke Energy Florida
Debt Securities, Available-for-sale
Estimated Fair Value	478
Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract]
Unrealized Holding Gains	95	82
Unrealized Holding Losses	4
Estimated Fair Value	597	663
Duke Energy Indiana
Debt Securities, Available-for-sale
Estimated Fair Value	46
NDTF
Available-for-sale Securities
Cash and cash equivalents	164	177
Equity Securities, FV-NI
Equity Securities, FV-NI, Accumulated Unrealized Gain	4,700	4,138
Equity Securities, FV-NI, Accumulated Unrealized Loss	35	54
Equity securities, FV-NI	6,754	6,235
Debt Securities, Available-for-sale
Estimated Fair Value	2,943	2,717
Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract]
Unrealized Holding Gains	4,795	4,295
Unrealized Holding Losses	50	55
Estimated Fair Value	9,861	9,129
NDTF | Duke Energy Carolinas
Available-for-sale Securities
Cash and cash equivalents	60	30
Equity Securities, FV-NI
Equity Securities, FV-NI, Accumulated Unrealized Gain	2,725	2,442
Equity Securities, FV-NI, Accumulated Unrealized Loss	14	23
Equity securities, FV-NI	3,912	3,685
Debt Securities, Available-for-sale
Estimated Fair Value	1,461	1,250
Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract]
Unrealized Holding Gains	2,775	2,529
Unrealized Holding Losses	20	24
Estimated Fair Value	5,433	4,965
NDTF | Progress Energy
Available-for-sale Securities
Cash and cash equivalents	104	147
Equity Securities, FV-NI
Equity Securities, FV-NI, Accumulated Unrealized Gain	1,975	1,696
Equity Securities, FV-NI, Accumulated Unrealized Loss	21	31
Equity securities, FV-NI	2,842	2,550
Debt Securities, Available-for-sale
Estimated Fair Value	1,482	1,467
Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract]
Unrealized Holding Gains	2,020	1,766
Unrealized Holding Losses	30	31
Estimated Fair Value	4,428	4,164
NDTF | Duke Energy Progress
Available-for-sale Securities
Cash and cash equivalents	92	76
Equity Securities, FV-NI
Equity Securities, FV-NI, Accumulated Unrealized Gain	1,882	1,617
Equity Securities, FV-NI, Accumulated Unrealized Loss	21	31
Equity securities, FV-NI	2,736	2,459
Debt Securities, Available-for-sale
Estimated Fair Value	1,030	993
Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract]
Unrealized Holding Gains	1,927	1,687
Unrealized Holding Losses	26	31
Estimated Fair Value	3,858	3,528
NDTF | Duke Energy Florida
Available-for-sale Securities
Cash and cash equivalents	12	71
Equity Securities, FV-NI
Equity Securities, FV-NI, Accumulated Unrealized Gain	93	79
Equity securities, FV-NI	106	91
Debt Securities, Available-for-sale
Estimated Fair Value	452	474
Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract]
Unrealized Holding Gains	93	79
Unrealized Holding Losses	4
Estimated Fair Value	570	636
Other Investments
Available-for-sale Securities
Cash and cash equivalents	87	127
Equity Securities, FV-NI
Equity Securities, FV-NI, Accumulated Unrealized Gain	83	79
Equity securities, FV-NI	145	146
Debt Securities, Available-for-sale
Estimated Fair Value	283	285
Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract]
Unrealized Holding Gains	90	92
Unrealized Holding Losses	2
Estimated Fair Value	515	558
Other Investments | Progress Energy
Available-for-sale Securities
Cash and cash equivalents	18	106
Debt Securities, Available-for-sale
Estimated Fair Value	26	26
Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract]
Unrealized Holding Gains	2	3
Estimated Fair Value	44	132
Other Investments | Duke Energy Progress
Available-for-sale Securities
Cash and cash equivalents	16	1
Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract]
Estimated Fair Value	16	1
Other Investments | Duke Energy Florida
Available-for-sale Securities
Cash and cash equivalents	1	1
Debt Securities, Available-for-sale
Estimated Fair Value	26	26
Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract]
Unrealized Holding Gains	2	3
Estimated Fair Value	27	27
Other Investments | Duke Energy Indiana
Available-for-sale Securities
Cash and cash equivalents	19	1
Equity Securities, FV-NI
Equity Securities, FV-NI, Accumulated Unrealized Gain	56	58
Equity securities, FV-NI	90	97
Debt Securities, Available-for-sale
Estimated Fair Value	46	45
Investments, Accumulated Gross Unrealized Gains (Losses) [Abstract]
Unrealized Holding Gains	57	59
Unrealized Holding Losses	1
Estimated Fair Value	155	143
Corporate debt securities | NDTF
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	44	76
Gross Unrealized Holding Losses	5	1
Estimated Fair Value	847	806
Corporate debt securities | NDTF | Duke Energy Carolinas
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	27	49
Gross Unrealized Holding Losses	3	1
Estimated Fair Value	495	510
Corporate debt securities | NDTF | Progress Energy
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	17	27
Gross Unrealized Holding Losses	2
Estimated Fair Value	352	296
Corporate debt securities | NDTF | Duke Energy Progress
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	17	27
Gross Unrealized Holding Losses	2
Estimated Fair Value	287	296
Corporate debt securities | NDTF | Duke Energy Florida
Debt Securities, Available-for-sale
Estimated Fair Value	65
Corporate debt securities | Other Investments
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	4	8
Gross Unrealized Holding Losses	1
Estimated Fair Value	130	110
Corporate debt securities | Other Investments | Duke Energy Indiana
Debt Securities, Available-for-sale
Estimated Fair Value	5	3
Municipal bonds | NDTF
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	13	22
Gross Unrealized Holding Losses	1
Estimated Fair Value	296	370
Municipal bonds | NDTF | Duke Energy Carolinas
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	1	6
Estimated Fair Value	24	91
Municipal bonds | NDTF | Progress Energy
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	12	16
Gross Unrealized Holding Losses	1
Estimated Fair Value	272	279
Municipal bonds | NDTF | Duke Energy Progress
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	12	16
Gross Unrealized Holding Losses	1
Estimated Fair Value	272	279
Municipal bonds | Other Investments
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	3	5
Gross Unrealized Holding Losses	1
Estimated Fair Value	69	86
Municipal bonds | Other Investments | Progress Energy
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	2	3
Estimated Fair Value	26	26
Municipal bonds | Other Investments | Duke Energy Florida
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	2	3
Estimated Fair Value	26	26
Municipal bonds | Other Investments | Duke Energy Indiana
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	1	1
Gross Unrealized Holding Losses	1
Estimated Fair Value	36	38
U.S. government bonds | NDTF
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	34	51
Gross Unrealized Holding Losses	8
Estimated Fair Value	1,605	1,361
U.S. government bonds | NDTF | Duke Energy Carolinas
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	18	25
Gross Unrealized Holding Losses	2
Estimated Fair Value	752	475
U.S. government bonds | NDTF | Progress Energy
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	16	26
Gross Unrealized Holding Losses	6
Estimated Fair Value	853	886
U.S. government bonds | NDTF | Duke Energy Progress
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	16	26
Gross Unrealized Holding Losses	2
Estimated Fair Value	466	412
U.S. government bonds | NDTF | Duke Energy Florida
Debt Securities, Available-for-sale
Gross Unrealized Holding Losses	4
Estimated Fair Value	387	474
U.S. government bonds | Other Investments
Debt Securities, Available-for-sale
Estimated Fair Value	50	42
U.S. government bonds | Other Investments | Duke Energy Indiana
Debt Securities, Available-for-sale
Estimated Fair Value	5	4
Other debt securities | NDTF
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	4	8
Gross Unrealized Holding Losses	1
Estimated Fair Value	195	180
Other debt securities | NDTF | Duke Energy Carolinas
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains	4	7
Gross Unrealized Holding Losses	1
Estimated Fair Value	190	174
Other debt securities | NDTF | Progress Energy
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		1
Estimated Fair Value	5	6
Other debt securities | NDTF | Duke Energy Progress
Debt Securities, Available-for-sale
Gross Unrealized Holding Gains		1
Estimated Fair Value	5	6
Other debt securities | Other Investments
Debt Securities, Available-for-sale
Estimated Fair Value	$ 34	$ 47

Investments in Debt and Equit_4

Investments in Debt and Equity Securities (Realized Gains and Losses) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
FV-NI:
Realized gains	$ 34	$ 13	$ 320	$ 338
Realized losses	40	16	100	148
AFS:
Realized gains	17	26	51	73
Realized losses	15	19	46	38
Duke Energy Carolinas
FV-NI:
Realized gains	25	10	243	46
Realized losses	29	12	68	82
AFS:
Realized gains	10	20	35	50
Realized losses	10	17	32	30
Progress Energy
FV-NI:
Realized gains	9	3	77	292
Realized losses	11	4	32	66
AFS:
Realized gains	7	6	14	17
Realized losses	6	2	12	7
Duke Energy Progress
FV-NI:
Realized gains	9	3	76	43
Realized losses	11	4	31	51
AFS:
Realized gains	6	6	13	17
Realized losses	5	$ 2	11	7
Duke Energy Florida
FV-NI:
Realized gains			1	249
Realized losses			1	$ 15
AFS:
Realized gains	1		1
Realized losses	$ 1		$ 1

Investments in Debt and Equit_5

Investments in Debt and Equity Securities (Maturities) (Details) $ in Millions	Sep. 30, 2021USD ($)
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	$ 151
Due after one through five years	954
Due after five through 10 years	639
Due after 10 years	1,482
Total	3,226
Duke Energy Carolinas
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	3
Due after one through five years	343
Due after five through 10 years	268
Due after 10 years	847
Total	1,461
Progress Energy
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	121
Due after one through five years	548
Due after five through 10 years	286
Due after 10 years	553
Total	1,508
Duke Energy Progress
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	22
Due after one through five years	244
Due after five through 10 years	247
Due after 10 years	517
Total	1,030
Duke Energy Florida
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	99
Due after one through five years	304
Due after five through 10 years	39
Due after 10 years	36
Total	478
Duke Energy Indiana
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	5
Due after one through five years	18
Due after five through 10 years	8
Due after 10 years	15
Total	$ 46

Fair Value Measurements (Fair V

Fair Value Measurements (Fair Value Measurement Amounts for Assets and Liabilities) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	$ 3,226
Derivative assets	543	$ 61
Total assets	10,919	9,748
Derivative liabilities	(415)	(324)
Net assets (liabilities)	10,504	9,424
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	27	1
Total assets	8,171	7,551
Derivative liabilities	(2)
Net assets (liabilities)	8,169	7,551
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	490	53
Total assets	2,673	2,144
Derivative liabilities	(256)	(240)
Net assets (liabilities)	2,417	1,904
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	26	7
Total assets	26	7
Derivative liabilities	(157)	(84)
Net assets (liabilities)	(131)	(77)
Not Categorized
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	49	46
Net assets (liabilities)	49	46
NDTF
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	164	177
Equity securities, FV-NI	6,754	6,235
Debt securities, available-for-sale	2,943	2,717
NDTF | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	164	177
Debt securities, available-for-sale	998	874
NDTF | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	1,945	1,843
NDTF equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	6,754	6,235
NDTF equity securities | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	6,705	6,189
NDTF equity securities | Not Categorized
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	49	46
Other Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	87	127
Equity securities, FV-NI	145	146
Debt securities, available-for-sale	283	285
Other Investments | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	87	127
Equity securities, FV-NI	145	146
Debt securities, available-for-sale	45	37
Other Investments | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	238	248
Duke Energy Carolinas
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	1,461
Derivative assets	271	20
Total assets	5,704	4,985
Derivative liabilities	(18)	(20)
Net assets (liabilities)	5,686	4,965
Duke Energy Carolinas | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	4,282	3,861
Net assets (liabilities)	4,282	3,861
Duke Energy Carolinas | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	271	20
Total assets	1,373	1,078
Derivative liabilities	(18)	(20)
Net assets (liabilities)	1,355	1,058
Duke Energy Carolinas | Not Categorized
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	49	46
Net assets (liabilities)	49	46
Duke Energy Carolinas | NDTF
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	60	30
Equity securities, FV-NI	3,912	3,685
Debt securities, available-for-sale	1,461	1,250
Duke Energy Carolinas | NDTF | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	60	30
Debt securities, available-for-sale	359	192
Duke Energy Carolinas | NDTF | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	1,102	1,058
Duke Energy Carolinas | NDTF equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	3,912	3,685
Duke Energy Carolinas | NDTF equity securities | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	3,863	3,639
Duke Energy Carolinas | NDTF equity securities | Not Categorized
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	49	46
Progress Energy
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	1,508
Derivative assets	215	33
Total assets	4,687	4,329
Derivative liabilities	(12)	(29)
Net assets (liabilities)	4,675	4,300
Progress Energy | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	3,603	3,485
Net assets (liabilities)	3,603	3,485
Progress Energy | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	215	33
Total assets	1,084	844
Derivative liabilities	(12)	(29)
Net assets (liabilities)	1,072	815
Progress Energy | NDTF
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	104	147
Equity securities, FV-NI	2,842	2,550
Debt securities, available-for-sale	1,482	1,467
Progress Energy | NDTF | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	104	147
Debt securities, available-for-sale	639	682
Progress Energy | NDTF | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	843	785
Progress Energy | NDTF equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	2,842	2,550
Progress Energy | NDTF equity securities | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	2,842	2,550
Progress Energy | Other Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	18	106
Debt securities, available-for-sale	26	26
Progress Energy | Other Investments | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	18	106
Progress Energy | Other Investments | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	26	26
Duke Energy Progress
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	1,030
Derivative assets	215	33
Total assets	4,089	3,562
Derivative liabilities		(14)
Net assets (liabilities)	4,089	3,548
Duke Energy Progress | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	3,122	2,773
Net assets (liabilities)	3,122	2,773
Duke Energy Progress | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	215	33
Total assets	967	789
Derivative liabilities		(14)
Net assets (liabilities)	967	775
Duke Energy Progress | NDTF
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	92	76
Equity securities, FV-NI	2,736	2,459
Debt securities, available-for-sale	1,030	993
Duke Energy Progress | NDTF | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	92	76
Debt securities, available-for-sale	278	237
Duke Energy Progress | NDTF | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	752	756
Duke Energy Progress | NDTF equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	2,736	2,459
Duke Energy Progress | NDTF equity securities | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	2,736	2,459
Duke Energy Progress | Other Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	16	1
Duke Energy Progress | Other Investments | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	16	1
Duke Energy Florida
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	478
Total assets	597	663
Derivative liabilities	(12)
Net assets (liabilities)	585	663
Duke Energy Florida | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	480	608
Net assets (liabilities)	480	608
Duke Energy Florida | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	117	55
Derivative liabilities	(12)
Net assets (liabilities)	105	55
Duke Energy Florida | NDTF
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	12	71
Equity securities, FV-NI	106	91
Debt securities, available-for-sale	452	474
Duke Energy Florida | NDTF | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	12	71
Debt securities, available-for-sale	361	445
Duke Energy Florida | NDTF | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	91	29
Duke Energy Florida | NDTF equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	106	91
Duke Energy Florida | NDTF equity securities | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, FV-NI	106	91
Duke Energy Florida | Other Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1	1
Debt securities, available-for-sale	26	26
Duke Energy Florida | Other Investments | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1	1
Duke Energy Florida | Other Investments | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	26	26
Duke Energy Indiana
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	46
Derivative assets	36	6
Total assets	191	149
Derivative liabilities	(2)	(1)
Net assets (liabilities)	189	148
Duke Energy Indiana | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	12
Total assets	121	98
Derivative liabilities	(2)	(1)
Net assets (liabilities)	119	97
Duke Energy Indiana | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	46	45
Net assets (liabilities)	46	45
Duke Energy Indiana | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	24	6
Total assets	24	6
Net assets (liabilities)	24	6
Duke Energy Indiana | Other Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	19	1
Equity securities, FV-NI	90	97
Debt securities, available-for-sale	46	45
Duke Energy Indiana | Other Investments | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	19	1
Equity securities, FV-NI	90	97
Duke Energy Indiana | Other Investments | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale	46	45
Piedmont
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	12	1
Derivative liabilities	(148)	(122)
Net assets (liabilities)	(136)	(121)
Piedmont | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	12	1
Net assets (liabilities)	12	1
Piedmont | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	(148)	(122)
Net assets (liabilities)	$ (148)	$ (122)

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	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivatives (net)
Balance at beginning of period	$ (131)	$ (92)	$ (77)	$ (102)
Total pretax realized or unrealized losses included in comprehensive income	(11)	(102)	(86)	(102)
Purchases, sales, issuances and settlements:
Purchases			21	14
Settlements	4	(3)	(4)	(18)
Total gains (losses) included on the Condensed Consolidated Balance Sheet	7	(6)	15	5
Balance at end of period	(131)	(203)	(131)	(203)
Duke Energy Indiana
Derivatives (net)
Balance at beginning of period	22	10	6	11
Purchases, sales, issuances and settlements:
Purchases			18	10
Settlements	(3)	(3)	(12)	(13)
Total gains (losses) included on the Condensed Consolidated Balance Sheet	5	1	12
Balance at end of period	$ 24	8	$ 24	8
Piedmont
Derivatives (net)
Balance at beginning of period		(105)		(117)
Purchases, sales, issuances and settlements:
Total (losses) gains and settlements		(6)		6
Balance at end of period		$ (111)		$ (111)

Fair Value Measurements (Quanti

Fair Value Measurements (Quantitative Level 3 Fair Value Disclosures) (Details) $ in Millions	Sep. 30, 2021USD ($)$ / MWh	Jun. 30, 2021USD ($)	Dec. 31, 2020USD ($)$ / MWh	Sep. 30, 2020USD ($)	Jun. 30, 2020USD ($)	Dec. 31, 2019USD ($)
Fair Value Measurement Inputs and Valuation Techniques
Net derivative asset (liability) | $	$ (131)	$ (131)	$ (77)	$ (203)	$ (92)	$ (102)
Electricity contracts | Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques
Net derivative asset (liability) | $			$ (84)
Electricity contracts | Discounted cash flow | Minimum
Fair Value Measurement Inputs and Valuation Techniques
Input measurements (in usd per MWh and usd per MMBtu)			14.68
Electricity contracts | Discounted cash flow | Maximum
Fair Value Measurement Inputs and Valuation Techniques
Input measurements (in usd per MWh and usd per MMBtu)			151.84
Electricity contracts | Discounted cash flow | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques
Input measurements (in usd per MWh and usd per MMBtu)			28,840,000
Electricity contracts | RTO auction pricing
Fair Value Measurement Inputs and Valuation Techniques
Net derivative asset (liability) | $	$ (157)
Electricity contracts | RTO auction pricing | Minimum
Fair Value Measurement Inputs and Valuation Techniques
Input measurements (in usd per MWh and usd per MMBtu)	18.02
Electricity contracts | RTO auction pricing | Maximum
Fair Value Measurement Inputs and Valuation Techniques
Input measurements (in usd per MWh and usd per MMBtu)	143.85
Electricity contracts | RTO auction pricing | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques
Input measurements (in usd per MWh and usd per MMBtu)	38.43
Duke Energy Ohio | FTRs | RTO auction pricing
Fair Value Measurement Inputs and Valuation Techniques
Net derivative asset (liability) | $	$ 2		$ 1
Duke Energy Ohio | FTRs | RTO auction pricing | Minimum
Fair Value Measurement Inputs and Valuation Techniques
Input measurements (in usd per MWh and usd per MMBtu)	0.06		0.25
Duke Energy Ohio | FTRs | RTO auction pricing | Maximum
Fair Value Measurement Inputs and Valuation Techniques
Input measurements (in usd per MWh and usd per MMBtu)	1.27		1.68
Duke Energy Ohio | FTRs | RTO auction pricing | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques
Input measurements (in usd per MWh and usd per MMBtu)	0.71		0.79
Duke Energy Indiana
Fair Value Measurement Inputs and Valuation Techniques
Net derivative asset (liability) | $	$ 24	$ 22	$ 6	$ 8	$ 10	$ 11
Duke Energy Indiana | FTRs | RTO auction pricing
Fair Value Measurement Inputs and Valuation Techniques
Net derivative asset (liability) | $	$ 24		$ 6
Duke Energy Indiana | FTRs | RTO auction pricing | Minimum
Fair Value Measurement Inputs and Valuation Techniques
Input measurements (in usd per MWh and usd per MMBtu)	(1.11)		(2.40)
Duke Energy Indiana | FTRs | RTO auction pricing | Maximum
Fair Value Measurement Inputs and Valuation Techniques
Input measurements (in usd per MWh and usd per MMBtu)	8.55		7.41
Duke Energy Indiana | FTRs | RTO auction pricing | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques
Input measurements (in usd per MWh and usd per MMBtu)	1.61		1.05

Fair Value Measurements (Other

Fair Value Measurements (Other Fair Value Disclosure) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 62,802	$ 59,863
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	69,381	69,292
Piedmont Natural Gas and Progress Energy
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized debt discount (premium), net	1,300	1,300
Duke Energy Carolinas | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	12,975	12,218
Duke Energy Carolinas | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	14,964	14,917
Progress Energy | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	19,488	19,264
Progress Energy | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	22,593	23,470
Duke Energy Progress | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	9,848	9,258
Duke Energy Progress | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	10,915	10,862
Duke Energy Florida | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	7,549	7,915
Duke Energy Florida | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	8,932	9,756
Duke Energy Ohio | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	3,092	3,089
Duke Energy Ohio | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	3,517	3,650
Duke Energy Indiana | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	4,092	4,091
Duke Energy Indiana | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	4,883	5,204
Piedmont | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	2,968	2,780
Piedmont | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 3,320	$ 3,306

Variable Interest Entities (Nar

Variable Interest Entities (Narrative) (Details) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Feb. 28, 2021
Variable Interest Entities [Line Items]
Equity in earnings (losses) of unconsolidated affiliates		$ 22,000,000	$ (80,000,000)	$ 14,000,000	$ (2,004,000,000)
ACP | ACP
Variable Interest Entities [Line Items]
Equity in earnings (losses) of unconsolidated affiliates	$ (2,100,000,000)
ACP | Current liabilities | ACP
Variable Interest Entities [Line Items]
Guarantor obligations settled							$ 855,000,000
VIE primary beneficiary
Variable Interest Entities [Line Items]
Variable interest entity, financial or other support, amount				$ 0		$ 0
VIE primary beneficiary | CRC
Variable Interest Entities [Line Items]
Percent of proceeds received as cash		75.00%		75.00%
Percent of proceeds received as subordinated note		25.00%		25.00%
Minimum equity balance required by Cinergy Receivables		$ 3,000,000		$ 3,000,000
VIE not primary beneficiary | ACP
Variable Interest Entities [Line Items]
Equity in earnings (losses) of unconsolidated affiliates			$ (163,000,000)		$ (4,505,000,000)
VIE not primary beneficiary | ACP
Variable Interest Entities [Line Items]
Variable interest entity ownership interest				47.00%
VIE not primary beneficiary | VIE With Ownership In Portfolio Of Wind Projects
Variable Interest Entities [Line Items]
Variable interest entity ownership interest				50.00%
VIE not primary beneficiary | OVEC
Variable Interest Entities [Line Items]
Variable interest entity ownership interest				9.00%

Variable Interest Entities (Sch

Variable Interest Entities (Schedule of Accounts Receivable Securitizations) (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Variable Interest Entities [Line Items]
Long-Term Debt	$ 57,929,000,000	$ 55,625,000,000
Duke Energy Carolinas
Variable Interest Entities [Line Items]
Long-Term Debt	12,318,000,000	11,412,000,000
Duke Energy Progress
Variable Interest Entities [Line Items]
Long-Term Debt	8,491,000,000	8,505,000,000
Duke Energy Florida
Variable Interest Entities [Line Items]
Long-Term Debt	7,273,000,000	7,092,000,000
CRC | VIE primary beneficiary
Variable Interest Entities [Line Items]
Facility size	350,000,000
Long-Term Debt	350,000,000	350,000,000
Accounts receivable from securitization	535,000,000	547,000,000
DERF | Duke Energy Carolinas | VIE primary beneficiary
Variable Interest Entities [Line Items]
Facility size	475,000,000
Long-Term Debt	475,000,000	364,000,000
Accounts receivable from securitization	915,000,000	696,000,000
DEPR | Duke Energy Progress | VIE primary beneficiary
Variable Interest Entities [Line Items]
Facility size	350,000,000
Long-Term Debt	350,000,000	250,000,000
Accounts receivable from securitization	532,000,000	500,000,000
DEFR | Duke Energy Florida | VIE primary beneficiary
Variable Interest Entities [Line Items]
Facility size	250,000,000
Long-Term Debt	250,000,000	250,000,000
Accounts receivable from securitization	$ 443,000,000	$ 397,000,000

Variable Interest Entities (S_2

Variable Interest Entities (Schedule of Consolidated VIEs) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Variable Interest Entities [Line Items]
Regulatory Assets: Current	$ 1,791	$ 1,641
Current Assets: Other	768	462
Other Noncurrent Assets: Regulatory assets	12,247	12,421
Property, Plant and Equipment: Cost	160,652	155,580
Accumulated depreciation and amortization	(50,543)	(48,827)
Other Noncurrent Assets: Other	3,686	3,601
Current Liabilities: Other	2,239	2,936
Current maturities of long-term debt	4,873	4,238
Long-Term Debt	57,929	55,625
Other Noncurrent Liabilities: AROs	12,278	12,286
Other Noncurrent Liabilities: Other	1,714	1,719
Duke Energy Florida
Variable Interest Entities [Line Items]
Regulatory Assets: Current	365	265
Current Assets: Other	35	41
Other Noncurrent Assets: Regulatory assets	1,829	1,799
Property, Plant and Equipment: Cost	23,300	22,123
Accumulated depreciation and amortization	(5,839)	(5,560)
Other Noncurrent Assets: Other	351	335
Current Liabilities: Other	403	374
Current maturities of long-term debt	276	823
Long-Term Debt	7,273	7,092
Other Noncurrent Liabilities: AROs	443	514
Other Noncurrent Liabilities: Other	265	209
DEFPF | Duke Energy Florida | VIE primary beneficiary
Variable Interest Entities [Line Items]
Receivables of VIEs	6	4
Regulatory Assets: Current	54	53
Current Assets: Other	17	39
Other Noncurrent Assets: Regulatory assets	896	937
Current Liabilities: Other	2	10
Current maturities of long-term debt	56	55
Long-Term Debt	946	1,002
Commercial Renewables | VIE primary beneficiary
Variable Interest Entities [Line Items]
Current Assets: Other	330	257
Property, Plant and Equipment: Cost	7,315	6,394
Accumulated depreciation and amortization	(1,414)	(1,242)
Other Noncurrent Assets: Other	110	67
Current maturities of long-term debt	165	167
Long-Term Debt	1,552	1,569
Other Noncurrent Liabilities: AROs	167	148
Other Noncurrent Liabilities: Other	$ 341	$ 316

Variable Interest Entities (S_3

Variable Interest Entities (Schedule of Non-Consolidated VIEs) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Variable Interest Entities [Line Items]
Investments in equity method unconsolidated affiliates	$ 951	$ 961
Other noncurrent assets	3,686	3,601
Total Assets	167,007	162,388
Other current liabilities	2,239	2,936
Other, noncurrent liabilities	1,714	1,719
VIE not primary beneficiary
Variable Interest Entities [Line Items]
Investments in equity method unconsolidated affiliates	480	530
Other noncurrent assets		31
Deferred tax asset	58
Total Assets	538	561
Other current liabilities	64	933
Other, noncurrent liabilities	66	18
Total liabilities	130	951
Net assets	408	(390)
Duke Energy Ohio
Variable Interest Entities [Line Items]
Other noncurrent assets	83	72
Total Assets	10,505	10,025
Other current liabilities	68	70
Other, noncurrent liabilities	92	99
Duke Energy Ohio | VIE not primary beneficiary
Variable Interest Entities [Line Items]
Receivables from affiliated companies	47	83
Total Assets	47	83
Net assets	47	83
Duke Energy Indiana
Variable Interest Entities [Line Items]
Other noncurrent assets	276	253
Total Assets	14,428	14,041
Other current liabilities	104	83
Other, noncurrent liabilities	53	30
Duke Energy Indiana | VIE not primary beneficiary
Variable Interest Entities [Line Items]
Receivables from affiliated companies	77	110
Total Assets	77	110
Net assets	77	110
Pipeline Investments | VIE not primary beneficiary
Variable Interest Entities [Line Items]
Investments in equity method unconsolidated affiliates	15
Other noncurrent assets		31
Deferred tax asset	58
Total Assets	73	31
Other current liabilities	61	928
Other, noncurrent liabilities	63	8
Total liabilities	124	936
Net assets	(51)	(905)
Commercial Renewables | VIE not primary beneficiary
Variable Interest Entities [Line Items]
Investments in equity method unconsolidated affiliates	465	530
Total Assets	465	530
Other current liabilities	3	5
Other, noncurrent liabilities	3	10
Total liabilities	6	15
Net assets	$ 459	$ 515

Variable Interest Entities (Rec

Variable Interest Entities (Receivables Sold) (Details) - VIE not primary beneficiary - CRC - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Duke Energy Ohio
Variable Interest Entities [Line Items]
Receivables sold	$ 218	$ 270
Less: Retained interests	47	83
Net receivables sold	171	187
Duke Energy Indiana
Variable Interest Entities [Line Items]
Receivables sold	328	344
Less: Retained interests	77	110
Net receivables sold	$ 251	$ 234

Variable Interest Entities (Sal

Variable Interest Entities (Sales and Cash Flows) (Details) - VIE not primary beneficiary - CRC - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Duke Energy Ohio
Sales
Receivables sold	$ 486	$ 462	$ 1,490	$ 1,428
Loss recognized on sale	2	2	7	8
Cash flows
Cash proceeds from receivables sold	490	449	1,519	1,439
Collection fees received		1	1	1
Return received on retained interests	1	1	3	3
Duke Energy Indiana
Sales
Receivables sold	794	717	2,176	1,947
Loss recognized on sale	4	3	10	9
Cash flows
Cash proceeds from receivables sold	798	689	2,199	1,941
Collection fees received			1	1
Return received on retained interests	$ 1	$ 1	$ 4	$ 4

Revenue (Remaining Performance

Revenue (Remaining Performance Obligations) (Details) $ in Millions	Sep. 30, 2021USD ($)
Progress Energy
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 278
Progress Energy | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction, period	6 months
Revenue, remaining performance obligation, amount	$ 24
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 107
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 44
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 45
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 7
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, expected timing of satisfaction, period
Revenue, remaining performance obligation, amount	$ 51
Duke Energy Progress
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 26
Duke Energy Progress | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction, period	6 months
Revenue, remaining performance obligation, amount	$ 2
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 8
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 8
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 8
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
Duke Energy Florida
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 252
Duke Energy Florida | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction, period	6 months
Revenue, remaining performance obligation, amount	$ 22
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 99
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 36
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 37
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 7
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, expected timing of satisfaction, period
Revenue, remaining performance obligation, amount	$ 51
Duke Energy Indiana
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 64
Duke Energy Indiana | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction, period	6 months
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
Revenue, remaining performance obligation, amount	$ 1
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 9
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 14
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 15
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, expected timing of satisfaction, period
Revenue, remaining performance obligation, amount	$ 25
Piedmont
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 605
Piedmont | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction, period	6 months
Revenue, remaining performance obligation, amount	$ 17
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 67
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 64
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 61
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, expected timing of satisfaction, period	1 year
Revenue, remaining performance obligation, amount	$ 60
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, expected timing of satisfaction, period
Revenue, remaining performance obligation, amount	$ 336

Revenue (Remaining Performanc_2

Revenue (Remaining Performance Obligations Total) (Details) $ in Millions	Sep. 30, 2021USD ($)
Progress Energy
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 278
Duke Energy Progress
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	26
Duke Energy Florida
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	252
Duke Energy Indiana
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	64
Piedmont
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 605

Revenue (Disaggregation of Reve

Revenue (Disaggregation of Revenue) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 6,894	$ 6,658	$ 18,655	$ 17,817
Revenue from sources other than contracts with customers	57	63	204	274
Total operating revenues	6,951	6,721	18,859	18,091
Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	6,560	6,378	17,142	16,538
Total operating revenues	6,560	6,371	17,161	16,571
Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,955	2,936	7,753	7,451
Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,873	1,804	4,805	4,691
Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	861	797	2,228	2,148
Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	619	603	1,644	1,535
Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	252	238	712	713
Gas Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	270	216	1,330	1,089
Total operating revenues	266	217	1,323	1,122
Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	129	112	747	631
Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Commercial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	78	64	373	308
Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	30	24	110	92
Gas Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	33	16	100	58
Commercial Renewables
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	56	57	163	170
Total operating revenues	117	126	355	378
Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	8	7	20	20
Total operating revenues	8	7	20	20
Duke Energy Carolinas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,120	2,068	5,474	5,423
Revenue from sources other than contracts with customers	(16)	(10)	(44)	(7)
Total operating revenues	2,104	2,058	5,430	5,416
Duke Energy Carolinas | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,120	2,068	5,474	5,423
Duke Energy Carolinas | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	892	883	2,368	2,316
Duke Energy Carolinas | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	685	664	1,685	1,720
Duke Energy Carolinas | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	360	342	872	871
Duke Energy Carolinas | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	111	117	341	332
Duke Energy Carolinas | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	72	62	208	184
Progress Energy
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,212	3,179	8,338	8,039
Revenue from sources other than contracts with customers	21	18	79	78
Total operating revenues	3,233	3,197	8,417	8,117
Progress Energy | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,212	3,179	8,338	8,039
Progress Energy | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,525	1,550	3,903	3,792
Progress Energy | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	826	805	2,170	2,080
Progress Energy | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	264	245	700	673
Progress Energy | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	399	412	1,056	1,018
Progress Energy | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	198	167	509	476
Duke Energy Progress
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,656	1,612	4,366	4,151
Revenue from sources other than contracts with customers	11	14	51	56
Total operating revenues	1,667	1,626	4,417	4,207
Duke Energy Progress | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,656	1,612	4,366	4,151
Duke Energy Progress | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	619	616	1,657	1,578
Duke Energy Progress | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	400	384	1,036	1,001
Duke Energy Progress | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	195	179	500	487
Duke Energy Progress | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	324	358	901	877
Duke Energy Progress | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	118	75	272	208
Duke Energy Florida
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,556	1,567	3,972	3,888
Revenue from sources other than contracts with customers	5		15	9
Total operating revenues	1,561	1,567	3,987	3,897
Duke Energy Florida | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,556	1,567	3,972	3,888
Duke Energy Florida | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	906	934	2,246	2,214
Duke Energy Florida | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	426	421	1,134	1,079
Duke Energy Florida | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	69	66	200	186
Duke Energy Florida | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	75	54	155	141
Duke Energy Florida | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	80	92	237	268
Duke Energy Ohio
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	506	481	1,498	1,405
Revenue from sources other than contracts with customers		(8)	(4)	(11)
Total operating revenues	506	473	1,494	1,394
Duke Energy Ohio | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	413	400	1,123	1,081
Duke Energy Ohio | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	223	213	589	558
Duke Energy Ohio | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	119	119	329	336
Duke Energy Ohio | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	35	35	99	103
Duke Energy Ohio | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	19	10	45	22
Duke Energy Ohio | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	17	23	61	62
Duke Energy Ohio | Gas Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	93	81	375	324
Duke Energy Ohio | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	62	55	241	214
Duke Energy Ohio | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Commercial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	24	20	99	86
Duke Energy Ohio | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3	3	14	12
Duke Energy Ohio | Gas Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4	3	21	12
Duke Energy Indiana
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	870	762	2,337	2,067
Revenue from sources other than contracts with customers	16	(1)	29	3
Total operating revenues	886	761	2,366	2,070
Duke Energy Indiana | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	870	762	2,337	2,067
Duke Energy Indiana | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	316	289	894	785
Duke Energy Indiana | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	240	212	619	554
Duke Energy Indiana | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	202	175	558	502
Duke Energy Indiana | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	89	64	202	163
Duke Energy Indiana | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	23	22	64	63
Piedmont
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	182	144	977	792
Revenue from sources other than contracts with customers	13	18	39	79
Total operating revenues	195	162	1,016	871
Piedmont | Gas Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	182	144	977	792
Piedmont | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	66	57	505	417
Piedmont | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Commercial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	58	44	273	222
Piedmont | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	26	22	96	80
Piedmont | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Power Generation
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	23	10	69	27
Piedmont | Gas Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 9	$ 11	$ 34	$ 46

Revenue (Reserve for Credit Los

Revenue (Reserve for Credit Losses for Trade and Other Receivables) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 123	$ 102	$ 146	$ 76
Cumulative Change in Accounting Principle	123	133	123	133
Write-Offs	(13)	12	(39)	(7)
Credit Loss Expense	11	(9)	40	24
Other Adjustments	2	28	(24)	35
Ending balance	123	133	123	133
Duke Energy Carolinas
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	42	14	23	10
Cumulative Change in Accounting Principle	42	22	42	22
Write-Offs	(3)	(2)	(10)	(8)
Credit Loss Expense	4		20	9
Other Adjustments	(1)	10	9	10
Ending balance	42	22	42	22
Progress Energy
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	36	29	37	16
Cumulative Change in Accounting Principle	36	37	36	37
Write-Offs	(6)	15	(20)	8
Credit Loss Expense	6	(16)	19	2
Other Adjustments		9		9
Ending balance	36	37	36	37
Duke Energy Progress
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	21	14	23	8
Cumulative Change in Accounting Principle	21	21	21	21
Write-Offs	(3)	13	(11)	8
Credit Loss Expense	3	(15)	9	(5)
Other Adjustments		9		9
Ending balance	21	21	21	21
Duke Energy Florida
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	16	14	14	7
Cumulative Change in Accounting Principle	16	16	16	16
Write-Offs	(3)	2	(9)
Credit Loss Expense	3		10	8
Other Adjustments			1
Ending balance	16	16	16	16
Duke Energy Ohio
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	4	5	4	4
Cumulative Change in Accounting Principle	4	5	4	5
Credit Loss Expense				1
Ending balance	4	5	4	5
Duke Energy Indiana
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	3	3	3	3
Cumulative Change in Accounting Principle	3	3	3	3
Ending balance	3	3	3	3
Piedmont
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	13	6	12	6
Cumulative Change in Accounting Principle	15	9	15	9
Write-Offs	(4)		(7)	(5)
Credit Loss Expense	2	3	6	7
Other Adjustments	4		4
Ending balance	$ 15	$ 9	$ 15	9
Cumulative Change in Accounting Principle
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance				5
Cumulative Change in Accounting Principle
Cumulative Change in Accounting Principle | Duke Energy Carolinas
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance				1
Cumulative Change in Accounting Principle
Cumulative Change in Accounting Principle | Progress Energy
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance				2
Cumulative Change in Accounting Principle
Cumulative Change in Accounting Principle | Duke Energy Progress
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance				1
Cumulative Change in Accounting Principle
Cumulative Change in Accounting Principle | Duke Energy Florida
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance				1
Cumulative Change in Accounting Principle
Cumulative Change in Accounting Principle | Piedmont
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance				$ 1
Cumulative Change in Accounting Principle

Revenue (Aging of Trade Receiva

Revenue (Aging of Trade Receivables) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Financing Receivable, Past Due [Line Items]
Unbilled Receivables	$ 826	$ 969
Trade and Other Receivables, not past due	2,201	1,789
Deferred Payment Arrangements	113	215
Trade and Other Receivables	3,552	3,299
30-60 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	194	185
60-90 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	57	22
90 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	161	119
Duke Energy Carolinas
Financing Receivable, Past Due [Line Items]
Unbilled Receivables	308	328
Trade and Other Receivables, not past due	689	445
Deferred Payment Arrangements	66	96
Trade and Other Receivables	1,235	966
Duke Energy Carolinas | 30-60 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	74	80
Duke Energy Carolinas | 60-90 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	30	1
Duke Energy Carolinas | 90 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	68	16
Progress Energy
Financing Receivable, Past Due [Line Items]
Unbilled Receivables	242	283
Trade and Other Receivables, not past due	910	707
Deferred Payment Arrangements	29	80
Trade and Other Receivables	1,285	1,166
Progress Energy | 30-60 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	63	54
Progress Energy | 60-90 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	14	10
Progress Energy | 90 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	27	32
Duke Energy Progress
Financing Receivable, Past Due [Line Items]
Unbilled Receivables	125	167
Trade and Other Receivables, not past due	521	398
Deferred Payment Arrangements	21	52
Trade and Other Receivables	715	655
Duke Energy Progress | 30-60 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	37	25
Duke Energy Progress | 60-90 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	6	4
Duke Energy Progress | 90 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	5	9
Duke Energy Florida
Financing Receivable, Past Due [Line Items]
Unbilled Receivables	117	116
Trade and Other Receivables, not past due	388	307
Deferred Payment Arrangements	8	28
Trade and Other Receivables	569	509
Duke Energy Florida | 30-60 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	26	29
Duke Energy Florida | 60-90 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	8	6
Duke Energy Florida | 90 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	22	23
Duke Energy Ohio
Financing Receivable, Past Due [Line Items]
Unbilled Receivables	5	2
Trade and Other Receivables, not past due	65	60
Deferred Payment Arrangements	2
Trade and Other Receivables	111	102
Duke Energy Ohio | CRC
Financing Receivable, Past Due [Line Items]
Unbilled Receivables	64	87
Duke Energy Ohio | 30-60 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	7	8
Duke Energy Ohio | 60-90 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	1	2
Duke Energy Ohio | 90 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	31	30
Duke Energy Indiana
Financing Receivable, Past Due [Line Items]
Unbilled Receivables	27	16
Trade and Other Receivables, not past due	41	26
Trade and Other Receivables	84	58
Duke Energy Indiana | CRC
Financing Receivable, Past Due [Line Items]
Unbilled Receivables	115	134
Duke Energy Indiana | 30-60 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	5	3
Duke Energy Indiana | 60-90 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	1	1
Duke Energy Indiana | 90 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	10	12
Piedmont
Financing Receivable, Past Due [Line Items]
Unbilled Receivables	7	86
Trade and Other Receivables, not past due	80	149
Deferred Payment Arrangements	6	7
Trade and Other Receivables	111	262
Piedmont | 30-60 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	6	8
Piedmont | 60-90 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	3	3
Piedmont | 90 days
Financing Receivable, Past Due [Line Items]
Trade and Other Receivables	$ 9	$ 9

Stockholders' Equity (Earnings

Stockholders' Equity (Earnings Per Share Data) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Class of Stock [Line Items]
Net income available to Duke Energy common stockholders	$ 1,366	$ 1,265	$ 3,070	$ 1,347
Accumulated preferred stock dividends adjustment	12	12	12	13
Less: Impact of participating securities	1	1	3	2
Income from continuing operations available to Duke Energy common stockholders	$ 1,377	$ 1,276	$ 3,079	$ 1,358
Weighted average common shares outstanding – basic (in shares)	769	735	769	735
Diluted (in shares)	769	735	769	735
EPS available to Duke Energy common stockholders
Basic (in usd per share)	$ 1.79	$ 1.74	$ 4	$ 1.85
Diluted (in usd per share)	$ 1.79	$ 1.74	$ 4	$ 1.85
Potentially dilutive items excluded from the calculation (in shares)	2	2	2	2
Common Stock
EPS available to Duke Energy common stockholders
Dividends declared per common share (in usd per share)	$ 0.985	$ 0.965	$ 2.915	$ 2.855
Preferred stock, Series A
EPS available to Duke Energy common stockholders
Dividends declared on preferred stock per depositary share (in usd per share)	0.359	0.359	$ 1.078	1.078
Cumulative dividend rate per annum			5.75%
Liquidation preference per share (in usd per share)	25		$ 25
Preferred stock, Series B
EPS available to Duke Energy common stockholders
Dividends declared on preferred stock per depositary share (in usd per share)	24.375	$ 24.375	$ 48.750	$ 49.292
Cumulative dividend rate per annum			4.875%
Liquidation preference per share (in usd per share)	$ 1,000		$ 1,000

Employee Benefit Plans (Compone

Employee Benefit Plans (Components of Net Periodic Pension Costs) (Details) - Qualified Pension Plans - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	$ 43	$ 41	$ 131	$ 124
Interest cost on projected benefit obligation	55	67	165	202
Expected return on plan assets	(139)	(143)	(418)	(429)
Amortization of actuarial loss	33	32	100	96
Amortization of prior service credit	(7)	(8)	(22)	(24)
Amortization of settlement charges	2	11	6	16
Net periodic pension costs	(13)		(38)	(15)
Duke Energy Carolinas
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	14	12	42	38
Interest cost on projected benefit obligation	13	16	38	47
Expected return on plan assets	(36)	(36)	(106)	(108)
Amortization of actuarial loss	7	7	22	21
Amortization of prior service credit	(2)	(2)	(6)	(6)
Amortization of settlement charges	1	6	4	8
Net periodic pension costs	(3)	3	(6)	0
Progress Energy
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	13	12	38	36
Interest cost on projected benefit obligation	17	21	52	64
Expected return on plan assets	(47)	(48)	(141)	(143)
Amortization of actuarial loss	10	10	29	30
Amortization of prior service credit	(1)		(2)	(2)
Amortization of settlement charges	1	5	2	6
Net periodic pension costs	(7)		(22)	(9)
Duke Energy Progress
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	7	6	22	20
Interest cost on projected benefit obligation	8	10	23	29
Expected return on plan assets	(21)	(22)	(63)	(66)
Amortization of actuarial loss	5	4	14	13
Amortization of prior service credit			(1)	(1)
Amortization of settlement charges		5	1	6
Net periodic pension costs	(1)	3	(4)	1
Duke Energy Florida
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	5	5	16	16
Interest cost on projected benefit obligation	10	12	29	35
Expected return on plan assets	(25)	(25)	(76)	(76)
Amortization of actuarial loss	5	6	15	17
Amortization of prior service credit	(1)		(1)	(1)
Amortization of settlement charges		1		1
Net periodic pension costs	(6)	(1)	(17)	(8)
Duke Energy Ohio
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	2	1	4	3
Interest cost on projected benefit obligation	2	4	9	12
Expected return on plan assets	(7)	(7)	(21)	(21)
Amortization of actuarial loss	2	2	5	5
Net periodic pension costs	(1)		(3)	(1)
Duke Energy Indiana
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	2	2	7	6
Interest cost on projected benefit obligation	5	6	14	17
Expected return on plan assets	(10)	(11)	(30)	(32)
Amortization of actuarial loss	3	3	10	9
Amortization of prior service credit			(1)	(1)
Amortization of settlement charges		1		1
Net periodic pension costs		1
Piedmont
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	1	1	4	4
Interest cost on projected benefit obligation	2	2	6	7
Expected return on plan assets	(5)	(5)	(15)	(16)
Amortization of actuarial loss	2	2	7	7
Amortization of prior service credit	(1)	(2)	(6)	(7)
Amortization of settlement charges	$ 1	1	1	1
Net periodic pension costs		$ (1)	$ (3)	$ (4)

Income Taxes (Effective Tax Rat

Income Taxes (Effective Tax Rates) (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract]
Effective tax rate	6.60%	7.80%	6.70%	(6.40%)
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]
Effective tax rate	2.90%	12.00%	3.60%	13.60%
Progress Energy
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract]
Effective tax rate	12.90%	10.40%	11.50%	13.40%
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]
Effective tax rate	6.30%	3.10%	5.90%	10.00%
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]
Effective tax rate	19.10%	21.40%	19.10%	20.30%
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]
Effective tax rate	13.40%	16.70%	15.30%	16.60%
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]
Effective tax rate	15.80%	19.60%	16.30%	19.40%
Piedmont
Reconciliation of Income Tax Expense at the U.S. Federal Statutory Tax Rate to the Actual Tax Expense from Continuing Operations [Abstract]
Effective tax rate	25.00%	16.70%	8.40%	3.70%