DTE Energy (DTE) 10-K 5 Feb 20 2019 FY Annual report Financial data

Document and Entity Information

Document and Entity Information Document and Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2019	Jan. 24, 2020	Jun. 28, 2019
Entity Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2019
Document Transition Report	false
Entity File Number	1-11607
Entity Registrant Name	DTE Energy Co
Entity Incorporation, State or Country Code	MI
Entity Tax Identification Number	38-3217752
Entity Address, Address Line One	One Energy Plaza
Entity Address, City or Town	Detroit
Entity Address, State or Province	MI
Entity Address, Postal Zip Code	48226-1279
City Area Code	313
Local Phone Number	235-4000
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 23.1
Entity Common Stock, Shares Outstanding		192,234,700
Documents Incorporated by Reference	Certain information in DTE Energy's definitive Proxy Statement for its 2020 Annual Meeting of Common Shareholders to be held May 7, 2020 , which will be filed with the Securities and Exchange Commission pursuant to Regulation 14A, not later than 120 days after the end of the registrant’s fiscal year covered by this report on Form 10-K, is incorporated herein by reference to Part III (Items 10, 11, 12, 13, and 14) of this Form 10-K. This combined Form 10-K is filed separately by two registrants: DTE Energy and DTE Electric. Information contained herein relating to any individual registrant is filed by such registrant solely on its own behalf. DTE Electric makes no representation as to information relating exclusively to DTE Energy. DTE Electric, a wholly-owned subsidiary of DTE Energy, meets the conditions set forth in General Instructions I(1)(a) and (b) of Form 10-K and is therefore filing this form with the reduced disclosure format specified in General Instruction I(2) of Form 10-K.
Entity Central Index Key	0000936340
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Amendment Flag	false
Common stock, without par value
Entity Information [Line Items]
Title of 12(b) Security	Common stock, without par value
Trading Symbol	DTE
Security Exchange Name	NYSE
2012 Series C 5.25% Junior Subordinated Debentures due 2062
Entity Information [Line Items]
Title of 12(b) Security	2012 Series C 5.25% Junior Subordinated Debentures due 2062
Trading Symbol	DTQ
Security Exchange Name	NYSE
2016 Series B 5.375% Junior Subordinated Debentures due 2076
Entity Information [Line Items]
Title of 12(b) Security	2016 Series B 5.375% Junior Subordinated Debentures due 2076
Trading Symbol	DTJ
Security Exchange Name	NYSE
2016 Series F 6.00% Junior Subordinated Debentures due 2076
Entity Information [Line Items]
Title of 12(b) Security	2016 Series F 6.00% Junior Subordinated Debentures due 2076
Trading Symbol	DTY
Security Exchange Name	NYSE
2017 Series E 5.25% Junior Subordinated Debentures due 2077
Entity Information [Line Items]
Title of 12(b) Security	2017 Series E 5.25% Junior Subordinated Debentures due 2077
Trading Symbol	DTW
Security Exchange Name	NYSE
2019 6.25% Corporate Units
Entity Information [Line Items]
Title of 12(b) Security	2019 6.25% Corporate Units
Trading Symbol	DTP
Security Exchange Name	NYSE
DTE Electric
Entity Information [Line Items]
Entity File Number	1-2198
Entity Registrant Name	DTE Electric Co
Entity Incorporation, State or Country Code	MI
Entity Tax Identification Number	38-0478650
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
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 Common Stock, Shares Outstanding		138,632,324
Entity Central Index Key	0000028385

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Revenues
Utility operations	$ 6,638	$ 6,670	$ 6,434
Non-utility operations	6,031	7,542	6,173
Operating Revenues	12,669	14,212	12,607
Operating Expenses
Fuel, purchased power, and gas — utility	1,798	1,981	1,881
Fuel, purchased power, and gas — non-utility	5,053	6,630	5,283
Operation and maintenance	2,419	2,451	2,270
Depreciation and amortization	1,263	1,124	1,030
Taxes other than income	414	405	391
Asset (gains) losses and impairments, net	15	27	41
Operating Expenses	10,962	12,618	10,896
Operating Income	1,707	1,594	1,711
Other (Income) and Deductions
Interest expense	641	559	536
Interest income	(17)	(12)	(12)
Non-operating retirement benefits, net	39	37	65
Other income	(350)	(333)	(268)
Other expenses	70	127	103
Other (Income) and Deductions	383	378	424
Income Before Income Taxes	1,324	1,216	1,287
Income Tax Expense	152	98	175
Net Income	1,172	1,118	1,112
Less: Net Income (Loss) Attributable to Noncontrolling Interests	3	(2)	(22)
Net Income Attributable to DTE Energy Company/DTE Electric Company	$ 1,169	$ 1,120	$ 1,134
Basic Earnings per Common Share
Net income attributable to DTE Energy Company (in dollars per share)	$ 6.32	$ 6.18	$ 6.32
Diluted Earnings per Common Share
Net income attributable to DTE Energy Company (in dollars per share)	$ 6.31	$ 6.17	$ 6.32
Weighted Average Common Shares Outstanding
Basic (in shares)	185	181	179
Diluted (in shares)	185	181	179
DTE Electric
Operating Revenues
Utility operations	$ 5,224	$ 5,298	$ 5,102
Operating Revenues	5,224	5,298
Operating Expenses
Fuel, purchased power, and gas — utility	1,390	1,552	1,454
Operation and maintenance	1,452	1,470	1,428
Depreciation and amortization	946	836	753
Taxes other than income	310	307	302
Asset (gains) losses and impairments, net	13	(1)	0
Operating Expenses	4,111	4,164	3,937
Operating Income	1,113	1,134	1,165
Other (Income) and Deductions
Interest expense	313	283	274
Interest income	(2)	0	0
Non-operating retirement benefits, net	(1)	0	0
Other income	(107)	(83)	(77)
Other expenses	56	77	40
Other (Income) and Deductions	259	277	237
Income Before Income Taxes	854	857	928
Income Tax Expense	138	193	327
Net Income Attributable to DTE Energy Company/DTE Electric Company	$ 716	$ 664	$ 601

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Net Income	$ 1,172	$ 1,118	$ 1,112
Net Income	1,169	1,120	1,134
Other comprehensive income (loss), net of tax:
Benefit obligations, net of taxes	8	8	10
Net unrealized gains (losses) on derivatives during the period, net of taxes	(12)
Net unrealized gains (losses) on derivatives during the period, net of taxes		(1)	1
Net unrealized gains on investments during the period, net of taxes	0	0	1
Foreign currency translation	1	(2)	1
Other comprehensive income (loss)	(3)	5	13
Comprehensive income	1,169	1,123	1,125
Less: Comprehensive income (loss) attributable to noncontrolling interests	3	(2)	(22)
Comprehensive Income Attributable to DTE Energy Company/DTE Electric Company	1,166	1,125	1,147
DTE Electric
Net Income	716	664	601
Other comprehensive income (loss), net of tax:
Net unrealized gains on investments during the period, net of taxes	0	0	1
Other comprehensive income (loss)	0	0	1
Comprehensive Income Attributable to DTE Energy Company/DTE Electric Company	$ 716	$ 664	$ 602

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Tax effect on benefit obligation	$ 2	$ 2	$ 5
Tax effect on net unrealized gains (losses) on derivatives during the period	(4)
Tax effect on net unrealized gains (losses) on derivatives during the period		0	0
Tax effect on net unrealized gains (losses) on investments during the period	0	0	1
DTE Electric
Tax effect on net unrealized gains (losses) on investments during the period	$ 0	$ 0	$ 1

Consolidated Statements of Fina

Consolidated Statements of Financial Position - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Current Assets
Cash and cash equivalents	$ 93	$ 71
Restricted cash	0	5
Accounts receivable (less allowance for doubtful accounts)
Customer	1,642	1,789
Other	245	108
Inventories
Fuel and gas	373	406
Materials and supplies	386	405
Derivative assets	133	102
Regulatory assets	5	153
Other	209	221
Total Current Assets	3,086	3,260
Investments
Nuclear decommissioning trust funds	1,661	1,378
Investments in equity method investees	1,862	1,771
Other	265	219
Total Investments	3,788	3,368
Property
Property, plant, and equipment	35,072	31,810
Accumulated depreciation and amortization	(9,755)	(10,160)
Property, plant and equipment, net	25,317	21,650
Other Assets
Goodwill	2,464	2,293
Regulatory assets	4,171	4,568
Intangible assets	2,393	849
Notes receivable	202	64
Derivative assets	41	31
Prepaid postretirement costs	69	45
Operating lease right-of-use assets	169
Other	182	160
Total Other Assets	9,691	8,010
Total Assets	41,882	36,288
Current Liabilities
Accounts payable	1,076	1,329
Accounts payable
Accrued interest	147	127
Dividends payable	195	172
Short-term borrowings	828	609
Current portion long-term debt, including finance leases	687	1,499
Derivative liabilities	83	67
Regulatory liabilities	65	126
Short-term borrowings
Operating lease liabilities	33
Acquisition related deferred payment	379	0
Other	504	509
Total Current Liabilities	3,997	4,438
Long-Term Debt (net of current portion)
Mortgage bonds, notes, and other	14,778	10,982
Junior subordinated debentures	1,146	1,145
Finance lease obligations	11
Finance lease obligations		7
Total Long-Term Debt (net of current portion)	15,935	12,134
Other Liabilities
Deferred income taxes	2,315	1,975
Regulatory liabilities	3,264	2,922
Asset retirement obligations	2,672	2,469
Unamortized investment tax credit	166	138
Derivative liabilities	86	89
Accrued pension liability	808	837
Nuclear decommissioning	249	205
Operating lease liability	127
Other	427	364
Total Other Liabilities	10,114	8,999
Commitments and Contingencies (Notes 10 and 19)
Equity
Common stock	5,233	4,245
Retained earnings	6,587	6,112
Accumulated other comprehensive loss	(148)	(120)
Total DTE Energy Company/DTE Electric Company Equity	11,672	10,237
Noncontrolling interests	164	480
Total Equity	11,836	10,717
Total Liabilities and Equity	41,882	36,288
DTE Electric
Current Assets
Cash and cash equivalents	12	18
Accounts receivable (less allowance for doubtful accounts)
Customer	729	750
Affiliates	25	11
Other	41	54
Inventories
Fuel and gas	187	171
Materials and supplies	280	279
Regulatory assets	5	148
Other	78	89
Total Current Assets	1,357	1,520
Investments
Nuclear decommissioning trust funds	1,661	1,378
Other	38	34
Total Investments	1,699	1,412
Property
Property, plant, and equipment	24,279	22,747
Accumulated depreciation and amortization	(6,706)	(7,310)
Property, plant and equipment, net	17,573	15,437
Other Assets
Regulatory assets	3,448	3,829
Intangible assets	15	21
Prepaid postretirement costs — affiliates	266	189
Operating lease right-of-use assets	87
Other	143	121
Total Other Assets	3,959	4,160
Total Assets	24,588	22,529
Accounts payable
Affiliates	59	71
Other	406	441
Accrued interest	84	74
Current portion long-term debt, including finance leases	636	4
Regulatory liabilities	40	98
Short-term borrowings
Affiliates	97	101
Other	354	149
Operating lease liabilities	12
Other	155	139
Total Current Liabilities	1,843	1,077
Long-Term Debt (net of current portion)
Mortgage bonds, notes, and other	6,548	6,538
Finance lease obligations	4
Finance lease obligations		7
Total Long-Term Debt (net of current portion)	6,552	6,545
Other Liabilities
Deferred income taxes	2,355	2,246
Regulatory liabilities	2,546	2,171
Asset retirement obligations	2,447	2,271
Unamortized investment tax credit	166	137
Nuclear decommissioning	249	205
Accrued pension liability — affiliates	717	718
Accrued postretirement liability — affiliates	367	278
Operating lease liability	67
Other	84	88
Total Other Liabilities	8,998	8,114
Commitments and Contingencies (Notes 10 and 19)
Equity
Common stock	4,811	4,631
Retained earnings	2,384	2,162
Total DTE Energy Company/DTE Electric Company Equity	7,195	6,793
Total Liabilities and Equity	$ 24,588	$ 22,529

Consolidated Statements of Fi_2

Consolidated Statements of Financial Position (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Current Assets:
Allowance for doubtful accounts	$ 91	$ 91
Stockholders' Equity:
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares issued (in shares)	192,208,533	181,925,281
Common stock, shares outstanding (in shares)	192,208,533	181,925,281
DTE Electric
Current Assets:
Allowance for doubtful accounts	$ 46	$ 53
Stockholders' Equity:
Common stock, par value (in dollars per share)	$ 10	$ 10
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares issued (in shares)	138,632,324	138,632,324
Common stock, shares outstanding (in shares)	138,632,324	138,632,324

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Activities
Net Income		$ 1,172	$ 1,118	$ 1,112
Net Income		1,169	1,120	1,134
Adjustments to reconcile Net Income to Net cash from operating activities:
Depreciation and amortization		1,263	1,124	1,030
Nuclear fuel amortization		60	45	53
Allowance for equity funds used during construction		(24)	(28)	(23)
Deferred income taxes		329	114	196
Equity earnings of equity method investees		(111)	(132)	(102)
Dividends from equity method investees		160	74	74
Asset (gains) losses and impairments, net		14	29	38
Changes in assets and liabilities:
Accounts receivable, net		49	(44)	(252)
Inventories		59	(32)	(4)
Prepaid postretirement benefit costs		(24)	(45)	0
Accounts payable		(288)	146	129
Accrued pension liability		(29)	(87)	(228)
Accrued postretirement liability		0	(61)	25
Derivative assets and liabilities		(28)	31	(94)
Regulatory assets and liabilities		160	15	217
Other current and noncurrent assets and liabilities		(113)	413	(54)
Net cash from operating activities		2,649	2,680	2,117
Investing Activities
Plant and equipment expenditures — utility		(2,724)	(2,439)	(2,037)
Plant and equipment expenditures — non-utility		(273)	(274)	(213)
Acquisition, net of cash acquired		(2,470)	0	0
Proceeds from sale of nuclear decommissioning trust fund assets		788	1,203	1,240
Investment in nuclear decommissioning trust funds		(794)	(1,188)	(1,226)
Distributions from equity method investees		10	9	10
Contributions to equity method investees		(149)	(637)	(299)
Notes receivable		(98)
Notes receivable			2	1
Other		(22)	(23)	(38)
Net cash used for investing activities		(5,732)	(3,347)	(2,562)
Financing Activities
Issuance of long-term debt, net of issuance costs		2,506	1,432	1,398
Redemption of long-term debt		(821)	(105)	(385)
Issuance of equity units, net of issuance costs		1,265	0	0
Short-term borrowings, net		219		122
Short-term borrowings, net			(12)
Issuance of common stock		1,023	0	0
Repurchase of common stock		0	0	(51)
Dividends on common stock		(692)	(620)	(592)
Contributions from noncontrolling interests, principally REF entities		38	53	50
Distributions to noncontrolling interests		(59)	(48)	(40)
Purchases of noncontrolling interest, principally SGG		(300)	0	0
Other		(79)	(46)	(81)
Net cash from (used for) financing activities		3,100	654	421
Net Increase (Decrease) in Cash, Cash Equivalents, and Restricted Cash		17	(13)	(24)
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period		76	89	113
Cash, Cash Equivalents, and Restricted Cash at End of Period		93	76	89
Supplemental disclosure of cash information
Cash paid (received) for: Interest, net of interest capitalized		595	572	495
Cash paid (received) for: Income taxes		18	(26)	4
Supplemental disclosure of non-cash investing and financing activities
Plant and equipment expenditures in accounts payable	[1]	311	307	295
Premium on equity units	[1]	150	0	0
DTE Electric
Operating Activities
Net Income		716	664	601
Adjustments to reconcile Net Income to Net cash from operating activities:
Depreciation and amortization		946	836	753
Nuclear fuel amortization		60	45	53
Allowance for equity funds used during construction		(22)	(19)	(18)
Deferred income taxes		97	189	345
Asset (gains) losses and impairments, net		13	0	0
Changes in assets and liabilities:
Accounts receivable, net		20	33	(80)
Inventories		(17)	15	31
Prepaid postretirement benefit costs — affiliates		(77)	(76)	1
Accounts payable		(57)	54	(2)
Accrued pension liability — affiliates		(1)	(93)	(197)
Accrued postretirement liability — affiliates		89	(33)	42
Regulatory assets and liabilities		139	4	202
Other current and noncurrent assets and liabilities		(197)	101	(147)
Net cash from operating activities		1,709	1,720	1,584
Investing Activities
Plant and equipment expenditures		(2,200)	(1,989)	(1,574)
Proceeds from sale of nuclear decommissioning trust fund assets		788	1,203	1,240
Investment in nuclear decommissioning trust funds		(794)	(1,188)	(1,226)
Other		(21)	(15)	18
Net cash used for investing activities		(2,227)	(1,989)	(1,542)
Financing Activities
Issuance of long-term debt, net of issuance costs		643	519	435
Redemption of long-term debt		0	0	(300)
Capital contribution by parent company		180	325	100
Short-term borrowings, net — affiliate		(4)	(15)	(1)
Short-term borrowings, net — other		205	(89)	176
Dividends on common stock		(494)	(461)	(432)
Other		(18)	(7)	(18)
Net cash from (used for) financing activities		512	272	(40)
Net Increase (Decrease) in Cash, Cash Equivalents, and Restricted Cash		(6)	3	2
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period		18	15	13
Cash, Cash Equivalents, and Restricted Cash at End of Period		12	18	15
Supplemental disclosure of cash information
Cash paid (received) for: Interest, net of interest capitalized		295	283	252
Cash paid (received) for: Income taxes		46	0	(16)
Supplemental disclosure of non-cash investing and financing activities
Plant and equipment expenditures in accounts payable		$ 192	$ 181	$ 191
[1]	See Note 15 to the Consolidated Financial Statements, " Long-Term Debt " for additional non-cash financing activity related to the remarketing of RSNs.

Consolidated Statements of Chan

Consolidated Statements of Changes in Equity - USD ($) $ in Millions	Total	Common Stock	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interests	DTE Electric	DTE ElectricCommon Stock	DTE ElectricAdditional Paid-in Capital	DTE ElectricRetained Earnings	DTE ElectricAccumulated Other Comprehensive Income (Loss)
Beginning balance (in shares) at Dec. 31, 2016		179,433,000					138,632,000
Beginning balance at Dec. 31, 2016	$ 9,499	$ 4,030	$ 5,114	$ (133)	$ 488
Beginning balance at Dec. 31, 2016						$ 5,995	$ 1,386	$ 2,820	$ 1,787	$ 2
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss)	1,112		1,134		(22)
Net Income	1,134					601			601
Dividends declared on common stock	(602)		(602)			(432)			(432)
Repurchase of common stock (in shares)		(524,000)
Repurchase of common stock	(51)	$ (51)
Other comprehensive income (loss), net of tax	13			13		1				1
Stock-based compensation, net contributions from (distributions to) noncontrolling interests, and other (in shares)		478,000
Stock-based compensation, net contributions from (distributions to) noncontrolling interests, and other	19	$ 10	(3)		12
Capital contribution by parent company						100		100
Ending balance (in shares) at Dec. 31, 2017		179,387,000					138,632,000
Ending balance at Dec. 31, 2017	9,990	$ 3,989	5,643	(120)	478
Ending balance at Dec. 31, 2017						6,265	$ 1,386	2,920	1,956	3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss)	1,118		1,120		(2)
Net Income	1,120					664			664
Dividends declared on common stock	(653)		(653)			(461)			(461)
Issuance of common stock (in shares)		255,000
Issuance of common stock	26	$ 26
Contribution of common stock to pension plan (in shares)		1,751,000
Contribution of common stock to pension plan	175	$ 175
Other comprehensive income (loss), net of tax	5			5		0
Stock-based compensation, net contributions from (distributions to) noncontrolling interests, and other (in shares)		532,000
Stock-based compensation, net contributions from (distributions to) noncontrolling interests, and other	$ 56	$ 55	(3)		4
Capital contribution by parent company						$ 325		325
Ending balance (in shares) at Dec. 31, 2018	181,925,281	181,925,000				138,632,324	138,632,000
Ending balance at Dec. 31, 2018	$ 10,717	$ 4,245	6,112	(120)	480
Ending balance at Dec. 31, 2018	10,237					$ 6,793	$ 1,386	3,245	2,162	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss)	1,172		1,169		3
Net Income	1,169					716			716
Dividends declared on common stock	(714)		(714)			(494)			(494)
Issuance of common stock (in shares)		8,634,000
Issuance of common stock	1,014	$ 1,014
Premium on equity units	(150)	(150)
Issuance costs of equity units	(30)	$ (30)
Contribution of common stock to pension plan (in shares)		815,000
Contribution of common stock to pension plan	100	$ 100
Other comprehensive income (loss), net of tax	(3)			(3)		0
Purchase of noncontrolling interests, principally SGG	(300)	$ (3)			(297)
Stock-based compensation, net contributions from (distributions to) noncontrolling interests, and other (in shares)		835,000
Stock-based compensation, net contributions from (distributions to) noncontrolling interests, and other	$ 30	$ 57	(5)		(22)
Capital contribution by parent company						$ 180		180
Ending balance (in shares) at Dec. 31, 2019	192,208,533	192,209,000				138,632,324	138,632,000
Ending balance at Dec. 31, 2019	$ 11,836	$ 5,233	$ 6,587	$ (148)	$ 164
Ending balance at Dec. 31, 2019	$ 11,672					$ 7,195	$ 1,386	$ 3,425	$ 2,384	$ 0

Consolidated Statements of Ch_2

Consolidated Statements of Changes in Equity (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Stockholders' Equity [Abstract]
Dividends declared on common stock (in dollars per share)	$ 3.85	$ 3.60	$ 3.36

Organization and Basis of Prese

Organization and Basis of Presentation	12 Months Ended
	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	ORGANIZATION AND BASIS OF PRESENTATION Corporate Structure DTE Energy owns the following businesses: • DTE Electric is a public utility engaged in the generation, purchase, distribution, and sale of electricity to approximately 2.2 million customers in southeastern Michigan; • DTE Gas is a public utility engaged in the purchase, storage, transportation, distribution, and sale of natural gas to approximately 1.3 million customers throughout Michigan and the sale of storage and transportation capacity; and • Other businesses primarily involved in 1) services related to the gathering, transportation, and storage of natural gas; 2) power and industrial projects; and 3) energy marketing and trading operations. DTE Electric and DTE Gas are regulated by the MPSC. Certain activities of DTE Electric and DTE Gas, as well as various other aspects of businesses under DTE Energy are regulated by the FERC. In addition, the Registrants are regulated by other federal and state regulatory agencies including the NRC, the EPA, the EGLE, and for DTE Energy, the CFTC. Basis of Presentation The accompanying Consolidated Financial Statements of the Registrants are prepared using accounting principles generally accepted in the United States of America. These accounting principles require management to use estimates and assumptions that impact reported amounts of assets, liabilities, revenues and expenses, and the disclosure of contingent assets and liabilities. Actual results may differ from the Registrants' estimates. The information in these combined notes relates to each of the Registrants as noted in the Index of Combined Notes to Consolidated Financial Statements. However, DTE Electric does not make any representation as to information related solely to DTE Energy or the subsidiaries of DTE Energy other than itself. Certain prior year balances for the Registrants were reclassified to match the current year's Consolidated Financial Statements presentation. Principles of Consolidation The Registrants consolidate all majority-owned subsidiaries and investments in entities in which they have controlling influence. Non-majority owned investments are accounted for using the equity method when the Registrants are able to significantly influence the operating policies of the investee. When the Registrants do not influence the operating policies of an investee, the cost method is used. These Consolidated Financial Statements also reflect the Registrants' proportionate interests in certain jointly-owned utility plants. The Registrants eliminate all intercompany balances and transactions. The Registrants evaluate whether an entity is a VIE whenever reconsideration events occur. The Registrants consolidate VIEs for which they are the primary beneficiary. If a Registrant is not the primary beneficiary and an ownership interest is held, the VIE is accounted for under the equity method of accounting. When assessing the determination of the primary beneficiary, a Registrant considers all relevant facts and circumstances, including: the power, through voting or similar rights, to direct the activities of the VIE that most significantly impact the VIE's economic performance and the obligation to absorb the expected losses and/or the right to receive the expected returns of the VIE. The Registrants perform ongoing reassessments of all VIEs to determine if the primary beneficiary status has changed. Legal entities within DTE Energy's Power and Industrial Projects segment enter into long-term contractual arrangements with customers to supply energy-related products or services. The entities are generally designed to pass-through the commodity risk associated with these contracts to the customers, with DTE Energy retaining operational and customer default risk. These entities generally are VIEs and consolidated when DTE Energy is the primary beneficiary. In addition, DTE Energy has interests in certain VIEs through which control of all significant activities is shared with partners, and therefore are generally accounted for under the equity method. DTE Energy currently owns an 85% interest in SGG, which owns and operates midstream natural gas assets. SGG has contracts through which certain construction risk is designed to pass-through to the customers, with DTE Energy retaining operational and customer default risk. SGG is a VIE with DTE Energy as the primary beneficiary. The Registrants have variable interests in NEXUS, which include DTE Energy's 50% ownership interest and DTE Electric's transportation services contract. NEXUS is a joint venture which owns a 256-mile pipeline to transport Utica and Marcellus shale gas to Ohio, Michigan, and Ontario market centers. NEXUS also owns Generation Pipeline, LLC, a 23-mile regulated pipeline system located in northern Ohio, which was acquired in September 2019. Refer to Note 4, "Acquisitions," for additional information. NEXUS is a VIE as it has insufficient equity at risk to finance its activities. The Registrants are not the primary beneficiaries, as the power to direct significant activities is shared between the owners of the equity interests. DTE Energy accounts for its ownership interest in NEXUS under the equity method. The Registrants hold ownership interests in certain limited partnerships. The limited partnerships include investment funds which support regional development and economic growth, as well as an operational business providing energy-related products. These entities are generally VIEs as a result of certain characteristics of the limited partnership voting rights. The ownership interests are accounted for under the equity method as the Registrants are not the primary beneficiaries. DTE Energy has variable interests in VIEs through certain of its long-term purchase and sale contracts. DTE Electric has variable interests in VIEs through certain of its long-term purchase contracts. As of December 31, 2019 , the carrying amount of assets and liabilities in DTE Energy's Consolidated Statements of Financial Position that relate to its variable interests under long-term purchase and sale contracts are predominantly related to working capital accounts and generally represent the amounts owed by or to DTE Energy for the deliveries associated with the current billing cycle under the contracts. As of December 31, 2019 , the carrying amount of assets and liabilities in DTE Electric's Consolidated Statements of Financial Position that relate to its variable interests under long-term purchase contracts are predominantly related to working capital accounts and generally represent the amounts owed by DTE Electric for the deliveries associated with the current billing cycle under the contracts. The Registrants have not provided any significant form of financial support associated with these long-term contracts. There is no material potential exposure to loss as a result of DTE Energy's variable interests through these long-term purchase and sale contracts. In addition, there is no material potential exposure to loss as a result of DTE Electric's variable interests through these long-term purchase contracts. The maximum risk exposure for consolidated VIEs is reflected on the Registrants' Consolidated Statements of Financial Position and for DTE Energy, in Note 19 to the Consolidated Financial Statements, " Commitments and Contingencies ," related to the REF guarantees and indemnities. For non-consolidated VIEs, the maximum risk exposure of the Registrants is generally limited to their investment, notes receivable, future funding commitments, and amounts which DTE Energy has guaranteed. See Note 19 to the Consolidated Financial Statements, " Commitments and Contingencies ," for further discussion of the NEXUS guarantee arrangements. The following table summarizes the major Consolidated Statements of Financial Position items for consolidated VIEs as of December 31, 2019 and 2018 . All assets and liabilities of a consolidated VIE are presented where it has been determined that a consolidated VIE has either (1) assets that can be used only to settle obligations of the VIE or (2) liabilities for which creditors do not have recourse to the general credit of the primary beneficiary. VIEs, in which DTE Energy holds a majority voting interest and is the primary beneficiary, that meet the definition of a business and whose assets can be used for purposes other than the settlement of the VIE's obligations have been excluded from the table below. Amounts for DTE Energy's consolidated VIEs are as follows: December 31, 2019 December 31, 2018 SGG (a) Other Total SGG (a) Other Total (In millions) ASSETS Cash and cash equivalents $ 16 $ 11 $ 27 $ 25 $ 14 $ 39 Restricted cash — — — — 5 5 Accounts receivable 8 19 27 9 37 46 Inventories — 74 74 1 92 93 Property, plant, and equipment, net 410 33 443 395 46 441 Goodwill 25 — 25 25 — 25 Intangible assets 542 — 542 557 — 557 Other current and long-term assets 2 — 2 3 — 3 $ 1,003 $ 137 $ 1,140 $ 1,015 $ 194 $ 1,209 LIABILITIES Accounts payable and accrued current liabilities $ 2 $ 13 $ 15 $ 3 $ 31 $ 34 Other current and long-term liabilities 7 7 14 9 10 19 $ 9 $ 20 $ 29 $ 12 $ 41 $ 53 _____________________________________ (a) Amounts shown are 100% of SGG's assets and liabilities, of which DTE Energy owns 85% at December 31, 2019 and 55% at December 31, 2018. Amounts for DTE Energy's non-consolidated VIEs are as follows: December 31, 2019 2018 (In millions) Investments in equity method investees $ 1,503 $ 1,425 Notes receivable $ 21 $ 15 Future funding commitments $ 63 $ 55 Equity Method Investments Investments in non-consolidated affiliates that are not controlled by the Registrants, but over which they have significant influence, are accounted for using the equity method. Certain of the equity method investees are also considered VIEs and disclosed in the non-consolidated VIEs table above. At December 31, 2019 and 2018 , DTE Energy's share of the underlying equity in the net assets of the investees exceeded the carrying amounts of Investments in equity method investees by $74 million and $59 million , respectively. The difference is being amortized over the life of the underlying assets. DTE Energy equity method investees are described below: Investments % Owned Segment 2019 2018 2019 2018 Description (In millions) Significant Equity Method Investees Gas Storage and Pipelines NEXUS Pipeline $ 1,345 $ 1,260 50% 50% 256-mile pipeline to transport Utica and Marcellus shale gas to Ohio, Michigan, and Ontario market centers. Also includes Generation Pipeline, a 23-mile pipeline located in northern Ohio Vector Pipeline 131 123 40% 40% 348-mile pipeline connecting Chicago, Michigan, and Ontario market centers Millennium Pipeline 209 202 26% 26% 263-mile pipeline serving markets in the Northeast 1,685 1,585 Other Equity Method Investees Other Segments 177 186 $ 1,862 $ 1,771 The balances in Other Equity Method Investees are individually insignificant and are primarily from the Power and Industrial Projects segment. These investments are comprised of projects that deliver energy and utility-type products and services to an industrial customer, sell electricity from renewable energy projects under long-term power purchase agreements, and produce and sell metallurgical coke. For further information by segment, see Note 23 to the Consolidated Financial Statements, " Segment and Related Information ." The following table presents summarized financial information of subsidiaries not consolidated and 50 percent or less owned by DTE Energy. The amounts included in the table below represents 100% of the results of continuing operations of such entities accounted for under the equity method of accounting. Summarized balance sheet data is as follows: December 31, 2019 2018 (In millions) Current Assets $ 374 $ 358 Non-current assets $ 5,260 $ 5,101 Current Liabilities $ 414 $ 391 Non-current liabilities $ 698 $ 762 Summarized income statement data is as follows: December 31, 2019 2018 2017 (In millions) Operating Revenues $ 1,210 $ 883 $ 756 Operating Expenses $ 853 $ 622 $ 561 Net Income $ 313 $ 365 $ 254

Significant Accounting Policies

Significant Accounting Policies	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Significant Accounting Policies	SIGNIFICANT ACCOUNTING POLICIES Other Income Other income for the Registrants is recognized for non-operating income such as equity earnings of equity method investees, allowance for equity funds used during construction, contract services, and gains (losses) from trading securities. DTE Energy's Power and Industrial Projects segment also recognizes Other income in connection with the sale of membership interests in reduced emissions fuel facilities to investors. In exchange for the cash received, the investors will receive a portion of the economic attributes of the facilities, including income tax attributes. The transactions are not treated as a sale of membership interests for financial reporting purposes. Other income related to fixed non-refundable cash payments received from investors for which the earnings process is not contingent upon production of refined coal is recognized on a straight-line basis over the non-cancelable contract term as the economic benefit from the ownership of the facility is transferred to investors. Other income related to cash payments that is contingent upon production of refined coal is considered earned and recognized when the contingency regarding the timing and amount of payment is resolved, generally as refined coal is produced and tax credits are generated. The following is a summary of DTE Energy's Other income: 2019 2018 2017 (In millions) Income from REF entities $ 130 $ 98 $ 77 Equity earnings of equity method investees 111 132 102 Gains from equity securities 37 6 26 Contract services 29 51 19 Allowance for equity funds used during construction 24 28 23 Other 19 18 21 $ 350 $ 333 $ 268 The following is a summary of DTE Electric's Other income: 2019 2018 2017 (In millions) Gains from equity securities allocated from DTE Energy $ 37 $ 6 $ 26 Contract services 32 51 21 Allowance for equity funds used during construction 22 19 18 Other 16 7 12 $ 107 $ 83 $ 77 For information on equity earnings of equity method investees by segment, see Note 23 to the Consolidated Financial Statements, " Segment and Related Information ." Accounting for ISO Transactions DTE Electric participates in the energy market through MISO. MISO requires that DTE Electric submit hourly day-ahead, real-time, and FTR bids and offers for energy at locations across the MISO region. DTE Electric accounts for MISO transactions on a net hourly basis in each of the day-ahead, real-time, and FTR markets. In any single hour, transactions in each of the MISO energy markets are netted based on MWh to determine if DTE Electric is in a net sale or purchase position. Net purchases are recorded in Fuel, purchased power, and gas — utility and net sales are recorded in Operating Revenues — Utility operations on the Registrants' Consolidated Statements of Operations. The Energy Trading segment participates in the energy markets through various ISOs and RTOs. These markets require that Energy Trading submits hourly day-ahead, real-time bids and offers for energy at locations across each region. Energy Trading submits bids in the annual and monthly auction revenue rights and FTR auctions to the RTOs. Energy Trading accounts for these transactions on a net hourly basis for the day-ahead, real-time, and FTR markets. These transactions are related to trading contracts which, if derivatives, are presented on a net basis in Operating Revenues — Non-utility operations, and if non-derivatives, the realized gains and losses for sales are recorded in Operating Revenues — Non-utility operations and purchases are recorded in Fuel, purchased power, and gas — non-utility in the DTE Energy Consolidated Statements of Operations. DTE Electric and Energy Trading record accruals for future net purchases adjustments based on historical experience and reconcile accruals to actual costs when invoices are received from MISO and other ISOs and RTOs. Derivatives Energy Trading classifies derivative transactions as revenue or expense based on the intent of the transaction (buy or sell). Revenues are recorded on a gross or net basis within the income statement depending upon whether it represents a non-trading activity or trading activity, respectively. For additional information, refer to Note 14 to the Consolidated Financial Statements, " Financial and Other Derivative Instruments ". Changes in Accumulated Other Comprehensive Income (Loss) Comprehensive income (loss) is the change in common shareholders’ equity during a period from transactions and events from non-owner sources, including Net Income. The amounts recorded to Accumulated other comprehensive income (loss) for DTE Energy include changes in benefit obligations, consisting of deferred actuarial losses and prior service costs, unrealized gains and losses from derivatives accounted for as cash flow hedges, DTE Energy's interest in other comprehensive income of equity investees which comprise the net unrealized gains and losses on investments, and foreign currency translation adjustments. DTE Energy releases income tax effects from accumulated other comprehensive income when the circumstances upon which they are premised cease to exist. Changes in Accumulated other comprehensive income (loss) are presented in DTE Energy's Consolidated Statements of Changes in Equity and DTE Electric's Consolidated Statements of Changes in Shareholder's Equity. For further discussion regarding changes in Accumulated other comprehensive income (loss), see Note 3 to the Consolidated Financial Statements, "New Accounting Pronouncements." For the years ended December 31, 2019 and 2018 , reclassifications out of Accumulated other comprehensive income (loss) not relating to the adoption of new accounting pronouncements for DTE Energy were not material. The following table summarizes the changes in DTE Energy's Accumulated other comprehensive income (loss) by component (a) for the years ended December 31, 2019 and 2018 : Net Unrealized Gain (Loss) on Derivatives Net Unrealized Loss on Investments Benefit Obligations (b) Foreign Currency Translation Total (In millions) Balance, December 31, 2017 $ (3 ) $ (2 ) $ (110 ) $ (5 ) $ (120 ) Other comprehensive loss before reclassifications (2 ) — (1 ) (2 ) (5 ) Amounts reclassified from Accumulated other comprehensive income (loss) 1 — 9 — 10 Net current-period Other comprehensive income (loss) (1 ) — 8 (2 ) 5 Implementation of ASU 2016-01 (7 ) 2 — — (5 ) Balance, December 31, 2018 $ (11 ) $ — $ (102 ) $ (7 ) $ (120 ) Other comprehensive income (loss) before reclassifications (14 ) — (7 ) 1 (20 ) Amounts reclassified from Accumulated other comprehensive income (loss) 2 — 15 — 17 Net current-period Other comprehensive income (loss) (12 ) — 8 1 (3 ) Implementation of ASU 2018-02 (2 ) — (23 ) — (25 ) Balance, December 31, 2019 $ (25 ) $ — $ (117 ) $ (6 ) $ (148 ) ______________________________________ (a) All amounts are net of tax, except for Foreign currency translation. (b) The amounts reclassified from Accumulated other comprehensive income (loss) are included in the computation of the net periodic pension and other postretirement benefit costs (see Note 21 to the Consolidated Financial Statements, " Retirement Benefits and Trusteed Assets "). Cash, Cash Equivalents, and Restricted Cash Cash and cash equivalents include cash on hand, cash in banks, and temporary investments purchased with remaining maturities of three months or less. Restricted cash consists of funds held to satisfy requirements of certain debt and DTE Energy partnership operating agreements. Restricted cash designated for interest and principal payments within one year is classified as a Current Asset. Receivables Accounts receivable are primarily composed of trade receivables and unbilled revenue. The Registrants' Accounts receivable are stated at net realizable value. The allowance for doubtful accounts for DTE Electric and DTE Gas is generally calculated using the aging approach that utilizes rates developed in reserve studies. DTE Electric and DTE Gas establish an allowance for uncollectible accounts based on historical losses and management’s assessment of existing economic conditions, customer trends, and other factors. Customer accounts are generally considered delinquent if the amount billed is not received by the due date, which is typically in 21 days, however, factors such as assistance programs may delay aggressive action. DTE Electric and DTE Gas assess late payment fees on trade receivables based on past-due terms with customers. Customer accounts are written off when collection efforts have been exhausted. The time period for write-off is 150 days after service has been terminated. The customer allowance for doubtful accounts for DTE Energy's other businesses is calculated based on specific review of probable future collections based on receivable balances generally in excess of 30 days. DTE Energy unbilled revenues of $0.9 billion and $1.0 billion at December 31, 2019 and 2018 , respectively, include $263 million and $264 million of DTE Electric unbilled revenues, respectively, included in Customer Accounts receivable. Notes Receivable Notes receivable, or financing receivables, for DTE Energy are primarily comprised of finance lease receivables and loans and are included in Notes receivable and Other current assets on DTE Energy’s Consolidated Statements of Financial Position. Notes receivable, or financing receivables, for DTE Electric are primarily comprised of loans. Notes receivable are typically considered delinquent when payment is not received for periods ranging from 60 to 120 days. The Registrants cease accruing interest (nonaccrual status), consider a note receivable impaired, and establish an allowance for credit loss when it is probable that all principal and interest amounts due will not be collected in accordance with the contractual terms of the note receivable. Cash payments received on nonaccrual status notes receivable, that do not bring the account contractually current, are first applied to contractually owed past due interest, with any remainder applied to principal. Accrual of interest is generally resumed when the note receivable becomes contractually current. In determining the allowance for credit losses for notes receivable, the Registrants consider the historical payment experience and other factors that are expected to have a specific impact on the counterparty’s ability to pay. In addition, the Registrants monitor the credit ratings of the counterparties from which they have notes receivable. Inventories Inventory related to utility operations is generally valued at average cost. Inventory related to non-utility operations is valued at the lower of cost or net realizable value. DTE Gas' natural gas inventory of $40 million and $48 million as of December 31, 2019 and 2018 , respectively, is determined using the last-in, first-out (LIFO) method. The replacement cost of gas in inventory exceeded the LIFO cost by $49 million and $113 million at December 31, 2019 and 2018 , respectively. Property, Retirement and Maintenance, and Depreciation and Amortization Property is stated at cost and includes construction-related labor, materials, overheads, and AFUDC for utility property. The cost of utility properties retired is charged to accumulated depreciation. Expenditures for maintenance and repairs are charged to expense when incurred. Utility property at DTE Electric and DTE Gas is depreciated over its estimated useful life using straight-line rates approved by the MPSC. DTE Energy's non-utility property is depreciated over its estimated useful life using the straight-line method. Depreciation and amortization expense also includes the amortization of certain regulatory assets for the Registrants. The cost of nuclear fuel is capitalized. The amortization of nuclear fuel is included within Fuel, purchased power, and gas — utility in the DTE Energy Consolidated Statements of Operations, and Fuel and purchased power in the DTE Electric Consolidated Statements of Operations, and is recorded using the units-of-production method. See Note 7 to the Consolidated Financial Statements, " Property, Plant, and Equipment ." Long-Lived Assets Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate the carrying amount of an asset may not be recoverable. If the carrying amount of the asset exceeds the expected undiscounted future cash flows generated by the asset, an impairment loss is recognized resulting in the asset being written down to its estimated fair value. Assets to be disposed of are reported at the lower of the carrying amount or fair value, less costs to sell. Intangible Assets The Registrants have certain Intangible assets as shown below: December 31, 2019 December 31, 2018 Useful Lives Gross Carrying Value Accumulated Amortization Net Carrying Value Gross Carrying Value Accumulated Amortization Net Carrying Value (In millions) Intangible assets subject to amortization Customer relationships 25 to 40 years (a) $ 2,252 $ (66 ) $ 2,186 $ 779 $ (44 ) $ 735 Contract intangibles 6 to 26 years 268 (76 ) 192 159 (66 ) 93 2,520 (142 ) 2,378 938 (110 ) 828 DTE Electric renewable energy credits (b) 15 — 15 20 — 20 DTE Electric emission allowances (b) — — — 1 — 1 DTE Electric Long-term intangible assets 15 — 15 21 — 21 DTE Energy Long-term intangible assets $ 2,535 $ (142 ) $ 2,393 $ 959 $ (110 ) $ 849 ______________________________________ (a) The useful lives of the customer relationship intangible assets are based on the number of years in which the assets are expected to economically contribute to the business. The expected economic benefit incorporates existing customer contracts and expected renewal rates based on the estimated volume and production lives of gas resources in the region. (b) Emission allowances and renewable energy credits are charged to expense, using average cost, as the allowances and credits are consumed in the operation of the business. The following table summarizes DTE Energy's estimated customer relationship and contract intangible amortization expense expected to be recognized during each year through 2024 : 2020 2021 2022 2023 2024 (In millions) Estimated amortization expense $ 82 $ 86 $ 86 $ 86 $ 86 DTE Energy amortizes customer relationship and contract intangible assets on a straight-line basis over the expected period of benefit. DTE Energy's Intangible assets amortization expense was $33 million in 2019 , $27 million in 2018 , and $29 million in 2017 . Excise and Sales Taxes The Registrants record the billing of excise and sales taxes as a receivable with an offsetting payable to the applicable taxing authority, with no net impact on the Registrants’ Consolidated Statements of Operations. Deferred Debt Costs The costs related to the issuance of long-term debt are deferred and amortized over the life of each debt issue. The deferred amounts are included as a direct deduction from the carrying amount of each debt issue in Mortgage bonds, notes, and other and Junior subordinated debentures on DTE Energy's Consolidated Statements of Financial Position and in Mortgage bonds, notes, and other on DTE Electric's Consolidated Statements of Financial Position. In accordance with MPSC regulations applicable to DTE Energy’s electric and gas utilities, the unamortized discount, premium, and expense related to utility debt redeemed with a refinancing are amortized over the life of the replacement issue. Discount, premium, and expense on early redemptions of debt associated with DTE Energy's non-utility operations are charged to earnings. Investments in Debt and Equity Securities The Registrants generally record investments in debt and equity securities at market value with unrealized gains or losses included in earnings. Changes in the fair value of Fermi 2 nuclear decommissioning investments are recorded as adjustments to Regulatory assets or liabilities, due to a recovery mechanism from customers. The Registrants' equity investments are reviewed for impairment each reporting period. If the assessment indicates that an impairment exists, a loss is recognized resulting in the equity investment being written down to its estimated fair value. See Note 13 of the Consolidated Financial Statements, " Fair Value ." DTE Energy Foundation There were no contributions made by DTE Energy to the DTE Energy Foundation for the year ended December 31, 2019 . DTE Energy's charitable contributions to the DTE Energy Foundation were $22 million and $43 million for the years ended December 31, 2018 and 2017 , respectively. The DTE Energy Foundation is a non-consolidated not-for-profit private foundation, the purpose of which is to contribute to and assist charitable organizations. Other Accounting Policies See the following notes for other accounting policies impacting the Registrants’ Consolidated Financial Statements: Note Title 5 Revenue 9 Asset Retirement Obligations 10 Regulatory Matters 11 Income Taxes 13 Fair Value 14 Financial and Other Derivative Instruments 18 Leases 21 Retirement Benefits and Trusteed Assets 22 Stock-Based Compensation

New Accounting Pronouncements

New Accounting Pronouncements	12 Months Ended
	Dec. 31, 2019
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
New Accounting Pronouncements	NEW ACCOUNTING PRONOUNCEMENTS Recently Adopted Pronouncements In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), as amended. This guidance requires a lessee to account for leases as finance or operating leases and disclose key information about leasing arrangements. Both types of leases will result in the lessee recognizing a right-of-use asset and a corresponding lease liability on its balance sheet, with differing methodology for income statement recognition, depending on the lease classification. The Registrants adopted the standard on January 1, 2019 using the prospective approach. The standard provides a number of transition practical expedients of which the Registrants elected the package of three expedients that must be taken together, allowing entities to not reassess whether an agreement is a lease, to carryforward the existing lease classification, and to not reassess initial direct costs associated with existing leases; but did not elect to apply hindsight in determining lease term and impairment of the right-to-use assets. The Registrants also elected to not evaluate land easements under the new guidance at adoption if they were not previously accounted for as leases. These practical expedients apply to leases that commenced prior to January 1, 2019. At adoption of the new standard, the Registrants recognized on the Consolidated Statements of Financial Position, right-of-use assets and lease liabilities for certain operating leases of approximately $137 million and $130 million , respectively, for DTE Energy and approximately $74 million and $67 million , respectively, for DTE Electric as of January 1, 2019. The right-of-use lease assets include $9 million of prepaid lease costs that have been reclassified from Other assets, current and noncurrent, and $2 million of deferred lease costs that have been reclassified from Other liabilities, current and noncurrent, for the Registrants. The adoption of the ASU did not have a significant impact on the Registrants' Consolidated Statements of Operations but required additional disclosures for leases. See Note 18 to the Consolidated Financial Statements, " Leases ." In February 2018, the FASB issued ASU No. 2018-02, Income Statement — Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income . The amendments in this update allow a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the TCJA. The amendments in this update also require entities to disclose their accounting policy for releasing income tax effects from accumulated other comprehensive income. The Registrants adopted the standard effective January 1, 2019. Upon adoption, DTE Energy reclassified $25 million of income tax effects from Accumulated other comprehensive income (loss) to Retained Earnings. Recently Issued Pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments — Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, as amended. The amendments in this update replace the incurred loss impairment methodology in current generally accepted accounting principles with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information, including forecasts, to develop credit loss estimates. The ASU requires entities to use the new methodology to measure impairment of financial instruments, including accounts receivable, and may result in earlier recognition of credit losses than under current generally accepted accounting principles. Entities will apply the new guidance as a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is adopted. The ASU is effective for the Registrants beginning after December 15, 2019, and interim periods therein. The Registrants will adopt the ASU on its effective date. The Registrants are currently assessing the impact of this standard on their Consolidated Financial Statements. In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurements (Topic 820): Disclosure Framework — Changes to the Disclosure Requirements for Fair Value Measurement . The amendments in this update modify the disclosure requirements on fair value measurements in Topic 820. The ASU is effective for the Registrants for fiscal years beginning after December 15, 2019, and interim periods therein. The Registrants will adopt the ASU on its effective date. The Registrants are currently assessing the impact of this standard on their Consolidated Financial Statements. In August 2018, the FASB issued ASU No. 2018-14, Compensation — Retirement Benefits — Defined Benefit Plans (Subtopic 715-20): Disclosure Framework — Changes to the Disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans . The amendments in this update modify the disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans. The ASU is effective for the Registrants for fiscal years ending after December 15, 2020. Early adoption is permitted. The Registrants anticipate adopting the ASU on its effective date. The Registrants are currently assessing the impact of this standard on their Consolidated Financial Statements. In August 2018, the FASB issued ASU No. 2018-15, Intangibles — Goodwill and Other — Internal-Use Software (Subtopic 350-40): Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That is a Service Contract . The amendments in this update align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal use software license). The ASU is effective for the Registrants for fiscal years beginning after December 15, 2019, and interim periods therein. The Registrants will adopt the ASU on its effective date. The ASU may be applied using either a retrospective or prospective approach. The Registrants will apply the ASU prospectively, and are currently assessing the impact of this standard on their Consolidated Financial Statements. In October 2018, the FASB issued ASU No. 2018-17, Consolidation (Topic 810): Targeted Improvements to Related Party Guidance for Variable Interest Entities . The amendments in this update modify the requirements for determining whether a decision-making fee is a variable interest and require reporting entities to consider indirect interests held through related parties under common control on a proportional basis. The ASU is effective for the Registrants for fiscal years beginning after December 15, 2019, and interim periods therein. The Registrants will adopt the ASU on its effective date. The Registrants are currently assessing the impact of this standard on their Consolidated Financial Statements. In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740) — Simplifying the Accounting for Income Taxes . The amendments in this update simplify the accounting for income taxes by removing certain exceptions and clarifying certain requirements regarding franchise taxes, goodwill, consolidated tax expenses, and annual effective tax rate calculations. The ASU is effective for the Registrants for fiscal years beginning after December 15, 2020. Early adoption is permitted. The Registrants are currently assessing the impact of this standard on their Consolidated Financial Statements.

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2019
Business Combinations [Abstract]
Acquisitions	ACQUISITIONS Electric Segment Acquisition Effective September 12, 2019, DTE Sustainable Generation closed on the purchase of an 89 MW renewable energy project located in Michigan from Heritage Sustainable Energy in support of DTE Energy's renewable energy goals. Direct transaction costs primarily related to advisory fees were immaterial and are included in Operation and maintenance in DTE Energy's Consolidated Statements of Operations. The fair value of consideration provided for the acquisition was approximately $175 million , of which $174 million has been paid in cash. The acquisition was accounted for using the acquisition method of accounting for business combinations. Accordingly, the cost was allocated to the underlying net assets based on their respective fair values as shown below: (In millions) Contract intangibles $ 109 Property, plant, and equipment, net 60 Working capital 6 Total $ 175 The intangible assets recorded pertain to existing customer contracts and were estimated by applying the income approach, based on discounted projected cash flows attributable to the existing agreements. The contract intangible assets are amortized on a straight-line basis with useful lives ranging from 11 years to 13 years , which is based on the remaining number of years the assets are expected to economically contribute to the business. The pro forma financial information has not been presented for DTE Energy because the effects of the acquisition were not material to the Consolidated Statements of Operations. In conjunction with the above acquisition, DTE Sustainable Generation closed on a purchase and sale agreement with Heritage Sustainable Energy in January 2020 to acquire an additional renewable energy project for approximately $33 million paid in cash. The acquired projects are non-utility operations and related revenues are classified accordingly as Operating Revenues - Non-utility operations within DTE Energy's Consolidated Statements of Operations and the Electric segment results of operations. Refer to Note 23 to the Consolidated Financial Statements, " Segment and Related Information ." Gas Storage and Pipelines Segment Acquisitions Generation Pipeline Acquisition Effective September 20, 2019, NEXUS closed on the purchase of Generation Pipeline, LLC, a pipeline system regulated by the Public Utilities Commission of Ohio. The 23-mile pipeline system supplies gas to industrial customers in the Toledo, OH area, has existing interconnects with ANR Pipeline Company and Panhandle Eastern Pipeline Company, and is located four miles from NEXUS. Total consideration paid for the acquired entity was approximately $163 million , of which DTE Energy's portion was 50% . DTE Energy accounts for its ownership interest in NEXUS under the equity method, which now includes equity in earnings related to Generation Pipeline, LLC. Blue Union and LEAP Acquisition On December 4, 2019, DTE Energy closed on the purchase of midstream natural gas assets in support of its strategy to continue to grow and earn competitive returns for shareholders. DTE Energy purchased 100 percent of M5 Louisiana Gathering, LLC and its wholly owned subsidiaries from Momentum Midstream and Indigo Natural Resources. The acquisition includes the Blue Union and LEAP assets which provide natural gas gathering and other midstream services to producers located primarily in Louisiana. The fair value of the consideration provided for the entities acquired was $2.74 billion and includes $2.36 billion paid in cash and an estimated $378 million of contingent consideration to be paid upon completion of a gathering pipeline in the second half of 2020. The contingent payment will range from $0 million to $385 million , with no payment due until the pipeline is completed. As of December 31, 2019, the liability for the contingent consideration payment and the related accretion expense of $1 million is included in a separate line in the Consolidated Statements of Financial Position. The acquisition was financed through the issuance of Equity Units, common stock, and Senior Notes. See Notes 12 and 15 to the Consolidated Financial Statements, " Common Stock and Earnings Per Share " and " Long-Term Debt ," respectively, for more information. The acquired assets are part of DTE Energy's non-utility Gas Storage and Pipelines segment. The acquisition was accounted for using the acquisition method of accounting for business combinations. The allocation of the purchase price included in the Consolidated Statements of Financial Position is preliminary and may be revised up to one year from the date of acquisition due to adjustments in the estimated fair value of the assets acquired and the liabilities assumed. The purchase price is subject to (i) final working capital settlement adjustments, and (ii) resolution of any indemnification claims that might be deducted from the $100 million of cash consideration paid and held in escrow. As such, DTE Energy cannot estimate the potential amount of the additional revisions to the purchase price allocation in 2020. The excess purchase price over the fair value of net assets acquired totaled approximately $171 million and was classified as goodwill. The factors contributing to the recognition of goodwill are based on various strategic benefits that are expected to be realized from the Blue Union and LEAP acquisition. The acquisition will provide DTE Energy with a platform for midstream growth and access to further investment opportunities in the Haynesville basin. The goodwill is expected to be deductible for income tax purposes. The preliminary allocation of the purchase price is based on estimated fair values of the Blue Union and LEAP assets acquired and liabilities assumed at the date of acquisition, December 4, 2019 . The components of the preliminary purchase price allocation are as follows: (In millions) Assets Cash $ 62 Accounts receivable 31 Property, plant, and equipment, net 1,035 Goodwill 171 Customer relationship intangibles 1,473 Other current assets 1 $ 2,773 Liabilities Accounts payable $ 26 Acquisition related deferred payment 378 Other current liabilities 2 Asset retirement obligations 9 $ 415 Total cash consideration $ 2,358 The intangible assets recorded as a result of the acquisition pertain to existing customer relationships, which were valued at approximately $1.47 billion as of the acquisition date. The fair value of the intangible assets acquired was estimated by applying the income approach. The income approach is based upon discounted projected future cash flows attributable to the existing contracts and agreements. The fair value measurement is based on significant unobservable inputs, including management estimates and assumptions, and thus represents a Level 3 measurement, pursuant to the applicable accounting guidance. Key estimates and inputs include revenue and expense projections and discount rates based on the risks associated with the entities. The intangible assets are amortized on a straight-line basis over a period of 40 years , which is based on the number of years the assets are expected to economically contribute to the business. The expected economic benefit incorporates existing customer contracts with a weighted-average amortization life of 13 years and expected renewal rates, based on the estimated volume and production lives of gas resources in the region. See Note 2 to the Consolidated Financial Statements, " Significant Accounting Policies ," for more information. DTE Energy has incurred $18 million of direct transaction costs for the year ended December 31, 2019. These costs are primarily related to advisory fees and are included in Operation and maintenance in DTE Energy's Consolidated Statements of Operations. Additionally, DTE Energy has incurred $49 million of issuance costs related to the acquisition financing, of which $10 million are included in Mortgage bonds, notes, and other, and $39 million are included in Common Stock in DTE Energy's Consolidated Statements of Financial Position. DTE Energy's 2019 Consolidated Statements of Operations include Operating Revenues — Non-utility operations of $15 million and Net Income of $3 million associated with the acquired entities for the one-month period following the acquisition date, excluding the $18 million transaction costs described above. The pro forma financial information has not been presented for DTE Energy because the effects of the acquisition were not material to the Consolidated Statements of Operations.

Revenue

Revenue	12 Months Ended
	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Revenue	REVENUE Significant Accounting Policy Upon the adoption of Topic 606, revenue is measured based upon the consideration specified in a contract with a customer at the time when performance obligations are satisfied. Under Topic 606, a performance obligation is a promise in a contract to transfer a distinct good or service or a series of distinct goods or services to the customer. The Registrants recognize revenue when performance obligations are satisfied by transferring control over a product or service to a customer. The Registrants have determined control to be transferred when the product is delivered or the service is provided to the customer. For the years ended December 31, 2019 and 2018 , recognition of revenue for the Registrants subsequent to the adoption of Topic 606 is substantially similar in amount and approach to that prior to adoption. Rates for DTE Electric and DTE Gas include provisions to adjust billings for fluctuations in fuel and purchased power costs, cost of natural gas, and certain other costs. Revenues are adjusted for differences between actual costs subject to reconciliation and the amounts billed in current rates. Under or over recovered revenues related to these cost recovery mechanisms are included in Regulatory assets or liabilities on the Registrants' Consolidated Statements of Financial Position and are recovered or returned to customers through adjustments to the billing factors. For discussion of derivative contracts, see Note 14 to the Consolidated Financial Statements, " Financial and Other Derivative Instruments ." Disaggregation of Revenue The following is a summary of revenues disaggregated by segment for DTE Energy: 2019 2018 (In millions) Electric (a) Residential $ 2,427 $ 2,494 Commercial 1,795 1,794 Industrial 659 690 Other (b) 348 320 Total Electric operating revenues (c) $ 5,229 $ 5,298 Gas Gas sales $ 1,043 $ 1,055 End User Transportation 219 232 Intermediate Transportation 78 58 Other (b) 142 91 Total Gas operating revenues (d) $ 1,482 $ 1,436 Other segment operating revenues Gas Storage and Pipelines (e) $ 501 $ 485 Power and Industrial Projects (f) $ 1,560 $ 2,204 Energy Trading (g) $ 4,610 $ 5,557 _______________________________________ (a) Revenues under the Electric segment generally represent those of DTE Electric. (b) Includes revenue adjustments related to various regulatory mechanisms. (c) Includes $22 million under Alternative Revenue Programs and $19 million of other revenues, which are both outside the scope of Topic 606 for the year ended December 31, 2019 and includes $21 million under Alternative Revenue Programs and $20 million of other revenues, which are both outside the scope of Topic 606 for the year ended December 31, 2018 . (d) Includes $8 million under Alternative Revenue Programs and $7 million of other revenues, which are both outside the scope of Topic 606 for the year ended December 31, 2019 and includes $2 million under Alternative Revenue Programs and $7 million of other revenues, which are both outside the scope of Topic 606 for the year ended December 31, 2018 . (e) Includes revenues outside the scope of Topic 606 primarily related to $9 million of contracts accounted for as leases for the year ended December 31, 2019 . (f) Includes revenues outside the scope of Topic 606 primarily related to $121 million and $125 million of contracts accounted for as leases for the years ended December 31, 2019 and December 31, 2018 , respectively. (g) Includes revenues outside the scope of Topic 606 primarily related to $3.4 billion and $4.5 billion of derivatives for the years ended December 31, 2019 and December 31, 2018 , respectively. Nature of Goods and Services The following is a description of principal activities, separated by reportable segments, from which DTE Energy generates revenue. For more detailed information about reportable segments, see Note 23 to the Consolidated Financial Statements, “ Segment and Related Information .” The Registrants have contracts with customers which may contain more than one performance obligation. When more than one performance obligation exists in a contract, the consideration under the contract is allocated to the performance obligations based on the relative standalone selling price. DTE Energy generally determines standalone selling prices based on the prices charged to customers or the use of the adjusted market assessment approach. The adjusted market assessment approach involves the evaluation of the market in which DTE Energy sells goods or services and estimating the price that a customer in that market would be willing to pay. Under Topic 606, when a customer simultaneously receives and consumes the product or service provided, revenue is considered to be recognized over time. Alternatively, if it is determined that the criteria for recognition of revenue over time is not met, the revenue is considered to be recognized at a point in time. Electric Electric consists principally of DTE Electric. Electric revenues are primarily comprised of the supply and delivery of electricity, and related capacity. Revenues are primarily associated with cancelable contracts, with the exception of certain long-term contracts with commercial and industrial customers. Revenues, including estimated unbilled amounts, are generally recognized over time based upon volumes delivered or through the passage of time ratably based upon providing a stand-ready service. The Registrants have determined that the above methods represent a faithful depiction of the transfer of control to the customer. Unbilled revenues are typically determined utilizing approved tariff rates and estimated meter volumes. Estimated unbilled amounts recognized in revenue are subject to adjustment in the following reporting period as actual volumes by customer class are known. Revenues are typically subject to tariff rates based upon customer class and type of service and are billed and received monthly. Tariff rates are determined by the MPSC on a per unit or monthly basis. Gas Gas consists principally of DTE Gas. Gas revenues are primarily comprised of the supply and delivery of natural gas, and other services including storage, transportation, and appliance maintenance. Revenues are primarily associated with cancelable contracts with the exception of certain long-term contracts with commercial and industrial customers. Revenues, including estimated unbilled amounts, are generally recognized over time based upon volumes delivered or through the passage of time ratably based upon providing a stand-ready service. DTE Energy has determined that the above methods represent a faithful depiction of the transfer of control to the customer. Unbilled revenues are typically determined using both estimated meter volumes and estimated usage based upon the number of unbilled days and historical temperatures. Estimated unbilled amounts recognized in revenue are subject to adjustment in the following reporting period as actual volumes by customer class and service type are known. Revenues are typically subject to tariff rates or other rates subject to regulatory oversight and are billed and received monthly. Tariff rates are determined by the MPSC on a per unit or monthly basis. Gas Storage and Pipelines Gas Storage and Pipelines revenues generally consist of services related to the gathering, transportation, and storage of natural gas. Contracts are primarily long-term in nature. Revenues, including estimated unbilled amounts, are generally recognized over time based upon services provided or through the passage of time ratably based upon providing a stand-ready service. DTE Energy has determined that the above methods represent a faithful depiction of the transfer of control to the customer. Revenues are typically billed and received monthly. Pricing for such revenues may consist of demand rates, commodity rates, transportation rates, and other associated fees. Consideration may consist of both fixed and variable components. Generally, uncertainties in the variable consideration components are resolved and revenues are known at the time of recognition. Power and Industrial Projects Power and Industrial Projects revenues include contracts accounted for as leases which are outside of the scope of Topic 606. For performance obligations within the scope of Topic 606, the timing of revenue recognition is dependent upon when control over the associated product or service is transferred. Revenues at Power and Industrial Projects, within the scope of Topic 606, generally consist of sales of refined coal, coal, blast furnace coke, coke oven gas, electricity, equipment maintenance services, and other energy related products and services. Revenues, including estimated unbilled amounts, for the sale of blast furnace coke are generally recognized at a point in time when the product is delivered, which represents the transfer of control to the customer. Other revenues are generally recognized over time based upon services provided or through the passage of time ratably based upon providing a stand-ready service. DTE Energy has determined that the above methods represent a faithful depiction of the transfer of control to the customer. Market based pricing structures exist in such contracts including adjustments for consumer price or other indices. Consideration may consist of both fixed and variable components. Generally, uncertainties in the variable consideration components are resolved and revenues are known at the time of recognition. Billing terms vary and are generally monthly with payment terms typically within 30 days following billing. Energy Trading Energy Trading revenues consist primarily of derivative contracts outside of the scope of Topic 606. For performance obligations within the scope of Topic 606, the timing of revenue recognition is dependent upon when control over the associated product or service is transferred. Revenues, including estimated unbilled amounts, within the scope of Topic 606 arising from the sale of natural gas, electricity, power capacity, and other energy related products are generally recognized over time based upon volumes delivered or through the passage of time ratably based upon providing a stand-ready service. DTE Energy has determined that the above methods represent a faithful depiction of the transfer of control to the customer. Revenues are known at the time of recognition. Payment for the aforementioned revenues is generally due from customers in the month following delivery. Revenues associated with RECs are recognized at a point in time when control of the RECs are transferred to the customer which is deemed to be when the subject RECs are entered for transfer to the customer in the applicable regulatory tracking system. Revenues associated with RECs under a wholesale full requirements power contract are deferred until control has been transferred. The deferred revenues represent a contract liability for which payment has been received and the amounts have been estimated using the adjusted market assessment approach. With the exception of RECs, generally all other performance obligations associated with wholesale full requirements power contracts are satisfied over time in conjunction with the delivery of power. At the time power is delivered, DTE Energy may not have control over the RECs as the RECs are not self-generated and may not yet have been procured resulting in deferred revenues. Deferred Revenue The following is a summary of deferred revenue activity: DTE Energy (In millions) Beginning Balance, January 1, 2019 $ 74 Increases due to cash received or receivable, excluding amounts recognized as revenue during the period 51 Revenue recognized that was included in the deferred revenue balance at the beginning of the period (50 ) Ending Balance, December 31, 2019 $ 75 The deferred revenues at DTE Energy generally represent amounts paid by or receivable from customers for which the associated performance obligation has not yet been satisfied. Deferred revenues include amounts associated with REC performance obligations under certain wholesale full requirements power contracts. Deferred revenues associated with RECs are recognized as revenue when control of the RECs has transferred. Other performance obligations associated with deferred revenues include providing products and services related to customer prepayments. Deferred revenues associated with these products and services are recognized when control has transferred to the customer. The following table represents deferred revenue amounts for DTE Energy that are expected to be recognized as revenue in future periods: DTE Energy (In millions) 2020 $ 43 2021 6 2022 7 2023 6 2024 3 2025 and thereafter 10 $ 75 Transaction Price Allocated to the Remaining Performance Obligations In accordance with optional exemptions available under Topic 606, the Registrants did not disclose the value of unsatisfied performance obligations for (1) contracts with an original expected length of one year or less, (2) with the exception of fixed consideration, contracts for which revenue is recognized at the amount to which the Registrants have the right to invoice for goods provided and services performed, and (3) contracts for which variable consideration relates entirely to an unsatisfied performance obligation. Such contracts consist of varying types of performance obligations across the segments, including the supply and delivery of energy related products and services. Contracts with variable volumes and/or variable pricing, including those with pricing provisions tied to a consumer price or other index, have also been excluded as the related consideration under the contract is variable at inception of the contract. Contract lengths vary from cancelable to multi-year. The Registrants expect to recognize revenue for the following amounts related to fixed consideration associated with remaining performance obligations in each of the future periods noted: DTE Energy DTE Electric (In millions) 2020 $ 253 $ 8 2021 292 8 2022 232 7 2023 164 7 2024 126 7 2025 and thereafter 538 — $ 1,605 $ 37 Other Matters The following table represents expenses recognized for estimated uncollectible accounts receivable: December 31, 2019 2018 (In millions) DTE Energy $ 111 $ 140 DTE Electric $ 65 $ 85

Goodwill

Goodwill	12 Months Ended
	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	GOODWILL DTE Energy has goodwill resulting from business combinations. The following is the summary of change in the carrying amount of goodwill for the years ended December 31: 2019 2018 (In millions) Balance as of January 1 $ 2,293 $ 2,293 Goodwill attributable to Gas Storage and Pipelines 2019 acquisition of Blue Union and LEAP 171 — Balance at December 31 $ 2,464 $ 2,293

Property, Plant, and Equipment

Property, Plant, and Equipment	12 Months Ended
	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Property, Plant, and Equipment	PROPERTY, PLANT, AND EQUIPMENT The following is a summary of Property, plant, and equipment by classification as of December 31: 2019 2018 Property, plant, and equipment (In millions) DTE Electric Generation $ 12,028 $ 11,027 Distribution 9,715 9,153 Other 2,536 2,567 Total DTE Electric 24,279 22,747 DTE Gas Distribution 4,164 3,823 Storage 570 548 Transmission and other 1,244 1,204 Total DTE Gas 5,978 5,575 Non-utility and other Gas Storage and Pipelines 3,524 2,307 Power and Industrial Projects 1,108 1,070 Other 183 111 Non-utility and other 4,815 3,488 Total DTE Energy 35,072 31,810 Accumulated depreciation and amortization DTE Electric Generation (3,460 ) (3,609 ) Distribution (2,553 ) (2,974 ) Other (693 ) (727 ) Total DTE Electric (6,706 ) (7,310 ) DTE Gas Distribution (1,334 ) (1,283 ) Storage (172 ) (165 ) Transmission and other (409 ) (404 ) Total DTE Gas (1,915 ) (1,852 ) Non-utility and other Gas Storage and Pipelines (459 ) (390 ) Power and Industrial Projects (604 ) (546 ) Other (71 ) (62 ) Non-utility and other (1,134 ) (998 ) Total DTE Energy (9,755 ) (10,160 ) Net DTE Energy Property, plant, and equipment $ 25,317 $ 21,650 Net DTE Electric Property, plant, and equipment $ 17,573 $ 15,437 The following is a summary of the Registrants' AFUDC and interest capitalized for the years ended December 31: DTE Energy DTE Electric 2019 2018 2019 2018 (In millions) Allowance for debt funds used during construction and interest capitalized $ 15 $ 15 $ 10 $ 9 Allowance for equity funds used during construction 24 28 22 19 Total $ 39 $ 43 $ 32 $ 28 The composite depreciation rate for DTE Electric was approximately 4.0% , 3.7% , and 3.6% in 2019 , 2018 and 2017 , respectively. The composite depreciation rate for DTE Gas was 2.7% for all periods. The average estimated useful life for each major class of utility Property, plant, and equipment as of December 31, 2019 follows: Estimated Useful Lives in Years Utility Generation Distribution Storage DTE Electric 34 38 N/A DTE Gas N/A 50 56 The estimated useful lives for DTE Electric's Other utility assets range from 3 to 80 years, while the estimated useful lives for DTE Gas' Transmission and other utility assets range from 3 to 70 years. The estimated useful lives for major classes of DTE Energy's non-utility assets and facilities range from 2 to 55 years. The following is a summary of Depreciation and amortization expense for DTE Energy: 2019 2018 2017 (In millions) Property, plant, and equipment $ 997 $ 878 $ 829 Regulatory assets and liabilities 227 212 165 Intangible assets 33 27 29 Other 6 7 7 $ 1,263 $ 1,124 $ 1,030 The following is a summary of Depreciation and amortization expense for DTE Electric: 2019 2018 2017 (In millions) Property, plant, and equipment $ 748 $ 652 $ 615 Regulatory assets and liabilities 193 179 133 Other 5 5 5 $ 946 $ 836 $ 753 Capitalized software costs are classified as Property, plant, and equipment and the related amortization is included in accumulated depreciation and amortization on the Registrants' Consolidated Financial Statements. The Registrants capitalize the costs associated with computer software developed or obtained for use in their businesses. The Registrants amortize capitalized software costs on a straight-line basis over the expected period of benefit, ranging from 3 to 15 years for DTE Energy and 3 to 15 years for DTE Electric. The following balances for capitalized software relate to DTE Energy: Year Ended December 31, 2019 2018 2017 (In millions) Amortization expense of capitalized software $ 123 $ 108 $ 101 Gross carrying value of capitalized software $ 906 $ 905 Accumulated amortization of capitalized software $ 520 $ 534 The following balances for capitalized software relate to DTE Electric: Year Ended December 31, 2019 2018 2017 (In millions) Amortization expense of capitalized software $ 112 $ 101 $ 93 Gross carrying value of capitalized software $ 811 $ 799 Accumulated amortization of capitalized software $ 462 $ 463

Jointly-Owned Utility Plant

Jointly-Owned Utility Plant	12 Months Ended
	Dec. 31, 2019
Jointly Owned Utility Plant, Net Ownership Amount [Abstract]
Jointly-Owned Utility Plant	JOINTLY-OWNED UTILITY PLANT DTE Electric has joint ownership interest in two power plants, Belle River and Ludington Hydroelectric Pumped Storage. DTE Electric’s share of direct expenses of the jointly-owned plants are included in Fuel, purchased power, and gas — utility and Operation and maintenance expenses in the DTE Energy Consolidated Statements of Operations and Fuel and purchased power — utility and Operation and maintenance expenses in the DTE Electric Consolidated Statements of Operations. DTE Electric's ownership information of the two utility plants as of December 31, 2019 was as follows: Belle River Ludington In-service date 1984-1985 1973 Total plant capacity 1,270 MW 2,220 MW Ownership interest 81% 49% Investment in Property, plant, and equipment (in millions) $ 1,903 $ 616 Accumulated depreciation (in millions) $ 896 $ 193 Belle River The Michigan Public Power Agency (MPPA) has ownership interests in Belle River Unit No. 1 and other related facilities. The MPPA is entitled to 19% of the total capacity and energy of the plant and is responsible for the same percentage of the plant’s operation, maintenance, and capital improvement costs. Ludington Hydroelectric Pumped Storage Consumers Energy Company has an ownership interest in the Ludington Hydroelectric Pumped Storage Plant. Consumers Energy is entitled to 51% of the total capacity and energy of the plant and is responsible for the same percentage of the plant’s operation, maintenance, and capital improvement costs.

Asset Retirement Obligations

Asset Retirement Obligations	12 Months Ended
	Dec. 31, 2019
Asset Retirement Obligation Disclosure [Abstract]
Asset Retirement Obligations	ASSET RETIREMENT OBLIGATIONS DTE Electric has a legal retirement obligation for the decommissioning costs for its Fermi 1 and Fermi 2 nuclear plants, dismantlement of facilities located on leased property, and various other operations. DTE Electric has conditional retirement obligations for asbestos and PCB removal at certain of its power plants and various distribution equipment. DTE Gas has conditional retirement obligations for gas pipelines, certain service centers, compressor and gate stations. The Registrants recognize such obligations as liabilities at fair market value when they are incurred, which generally is at the time the associated assets are placed in service. Fair value is measured using expected future cash outflows discounted at the Registrants' credit-adjusted risk-free rate. For its utility operations, the Registrants recognize in the Consolidated Statements of Operations removal costs in accordance with regulatory treatment. Any differences between costs recognized related to asset retirement and those reflected in rates are recognized as either a Regulatory asset or liability on the Consolidated Statements of Financial Position. If a reasonable estimate of fair value cannot be made in the period in which the retirement obligation is incurred, such as for assets with indeterminate lives, the liability is recognized when a reasonable estimate of fair value can be made. Natural gas storage system and certain other distribution assets for DTE Gas and substations, manholes, and certain other distribution assets for DTE Electric have an indeterminate life. Therefore, no liability has been recorded for these assets. Changes to asset retirement obligations for 2019 , 2018 , and 2017 were as follows: 2019 2018 2017 DTE Energy (In millions) Asset retirement obligations at January 1 $ 2,469 $ 2,320 $ 2,197 Accretion 149 140 131 Liabilities incurred 20 27 2 Liabilities settled (17 ) (16 ) (6 ) Revision in estimated cash flows 51 (2 ) (4 ) Asset retirement obligations at December 31 $ 2,672 $ 2,469 $ 2,320 2019 2018 2017 DTE Electric (In millions) Asset retirement obligations at January 1 $ 2,271 $ 2,125 $ 2,012 Accretion 138 129 120 Liabilities incurred 1 27 1 Liabilities settled (14 ) (8 ) (2 ) Revision in estimated cash flows 51 (2 ) (6 ) Asset retirement obligations at December 31 $ 2,447 $ 2,271 $ 2,125 Approximately $2.1 billion of the asset retirement obligations represent nuclear decommissioning liabilities that are funded through a surcharge to electric customers over the life of the Fermi 2 nuclear plant. The NRC has jurisdiction over the decommissioning of nuclear power plants and requires minimum decommissioning funding based upon a formula. The MPSC and FERC regulate the recovery of costs of decommissioning nuclear power plants and both require the use of external trust funds to finance the decommissioning of Fermi 2. Rates approved by the MPSC provide for the recovery of decommissioning costs of Fermi 2 and the disposal of low-level radioactive waste. DTE Electric believes the MPSC collections will be adequate to fund the estimated cost of decommissioning. The decommissioning assets, anticipated earnings thereon, and future revenues from decommissioning collections will be used to decommission Fermi 2. DTE Electric expects the liabilities to be reduced to zero at the conclusion of the decommissioning activities. If amounts remain in the trust funds for Fermi 2 following the completion of the decommissioning activities, those amounts will be disbursed based on rulings by the MPSC and FERC. A portion of the funds recovered through the Fermi 2 decommissioning surcharge and deposited in external trust accounts is designated for the removal of non-radioactive assets and returning the site to greenfield. This removal and greenfielding is not considered a legal liability. Therefore, it is not included in the asset retirement obligation, but is reflected as the Nuclear decommissioning liability. The decommissioning of Fermi 1 is funded by DTE Electric. Contributions to the Fermi 1 trust are discretionary. For additional discussion of Nuclear decommissioning trust fund assets, see Note 13 to the Consolidated Financial Statements, " Fair Value ."

Regulatory Matters

Regulatory Matters	12 Months Ended
	Dec. 31, 2019
Regulatory Assets and Liabilities Disclosure [Abstract]
Regulatory Matters	REGULATORY MATTERS Regulation DTE Electric and DTE Gas are subject to the regulatory jurisdiction of the MPSC, which issues orders pertaining to rates, recovery of certain costs, including the costs of generating facilities and regulatory assets, conditions of service, accounting, and operating-related matters. DTE Electric is also regulated by the FERC with respect to financing authorization and wholesale electric activities. Regulation results in differences in the application of generally accepted accounting principles between regulated and non-regulated businesses. The Registrants are unable to predict the outcome of the unresolved regulatory matters discussed herein. Resolution of these matters is dependent upon future MPSC orders and appeals, which may materially impact the Consolidated Financial Statements of the Registrants. Regulatory Assets and Liabilities DTE Electric and DTE Gas are required to record Regulatory assets and liabilities for certain transactions that would have been treated as revenue or expense in non-regulated businesses. Continued applicability of regulatory accounting treatment requires that rates be designed to recover specific costs of providing regulated services and be charged to and collected from customers. Future regulatory changes could result in the discontinuance of this accounting treatment for Regulatory assets and liabilities for some or all of the Registrants' businesses and may require the write-off of the portion of any Regulatory asset or liability that was no longer probable of recovery through regulated rates. Management believes that currently available facts support the continued use of Regulatory assets and liabilities and that all Regulatory assets and liabilities are recoverable or refundable in the current regulatory environment. The following are balances and a brief description of the Registrants' Regulatory assets and liabilities at December 31: DTE Energy DTE Electric 2019 2018 2019 2018 Assets (In millions) Recoverable pension and other postretirement costs Pension $ 1,983 $ 1,961 $ 1,497 $ 1,476 Other postretirement costs 201 213 131 121 Fermi 2 asset retirement obligation 669 778 669 778 Recoverable undepreciated costs on retiring plants 657 630 657 630 Recoverable Michigan income taxes 189 201 152 161 Deferred environmental costs 66 69 — — Recoverable income taxes related to AFUDC equity 56 51 47 41 Unamortized loss on reacquired debt 56 60 40 43 Customer360 deferred costs 55 42 55 42 Energy Waste Reduction incentive 54 49 43 39 Nuclear Performance Evaluation and Review Committee Tracker 48 43 48 43 Enhanced Tree Trimming Program deferred costs 43 — 43 — Other recoverable income taxes 20 23 20 23 Non-service pension and other postretirement costs 15 10 — — Transitional Reconciliation Mechanism 10 21 10 21 Accrued PSCR/GCR revenue 3 116 3 116 Removal costs asset — 407 — 407 Other 51 47 38 36 4,176 4,721 3,453 3,977 Less amount included in Current Assets (5 ) (153 ) (5 ) (148 ) $ 4,171 $ 4,568 $ 3,448 $ 3,829 DTE Energy DTE Electric 2019 2018 2019 2018 Liabilities (In millions) Refundable federal income taxes $ 2,359 $ 2,410 $ 1,911 $ 1,958 Removal costs liability 700 253 483 — Negative other postretirement offset 93 101 69 79 Renewable energy 54 86 54 86 Non-service pension and other postretirement costs 46 22 21 11 Accrued PSCR/GCR refund 23 — — — TCJA rate reduction liability 1 118 — 93 Other 53 58 48 42 3,329 3,048 2,586 2,269 Less amount included in Current Liabilities (65 ) (126 ) (40 ) (98 ) $ 3,264 $ 2,922 $ 2,546 $ 2,171 As noted below, certain Regulatory assets for which costs have been incurred have been included (or are expected to be included, for costs incurred subsequent to the most recently approved rate case) in DTE Electric's or DTE Gas' rate base, thereby providing a return on invested costs (except as noted). Certain other regulatory assets are not included in rate base but accrue recoverable carrying charges until surcharges to collect the assets are billed. Certain Regulatory assets do not result from cash expenditures and therefore do not represent investments included in rate base or have offsetting liabilities that reduce rate base. ASSETS • Recoverable pension and other postretirement costs — Accounting standards for pension and other postretirement benefit costs require, among other things, the recognition in Other comprehensive income of the actuarial gains or losses and the prior service costs that arise during the period but that are not immediately recognized as components of net periodic benefit costs. DTE Electric and DTE Gas record the impact of actuarial gains or losses and prior service costs as a Regulatory asset since the traditional rate setting process allows for the recovery of pension and other postretirement costs. The asset will reverse as the deferred items are amortized and recognized as components of net periodic benefit costs. (a) • Fermi 2 asset retirement obligation — This obligation is for Fermi 2 decommissioning costs. The asset captures the timing differences between expense recognition and current recovery in rates and will reverse over the remaining life of the related plant. (a) • Recoverable undepreciated costs on retiring plants — Deferral of estimated remaining balances associated with coal power plants expected to be retired by 2023. • Recoverable Michigan income taxes — The State of Michigan enacted a corporate income tax resulting in the establishment of state deferred tax liabilities for DTE Energy's utilities. Offsetting Regulatory assets were also recorded as the impacts of the deferred tax liabilities will be reflected in rates as the related taxable temporary differences reverse and flow through current income tax expense. • Deferred environmental costs — The MPSC approved the deferral of investigation and remediation costs associated with DTE Gas' former MGP sites. Amortization of deferred costs is over a ten -year period beginning in the year after costs were incurred, with recovery (net of any insurance proceeds) through base rate filings. (a) • Recoverable income taxes related to AFUDC equity — Accounting standards for income taxes require recognition of a deferred tax liability for the equity component of AFUDC. A regulatory asset is required for the future increase in taxes payable related to the equity component of AFUDC that will be recovered from customers through future rates over the remaining life of the related plant. • Unamortized loss on reacquired debt — The unamortized discount, premium, and expense related to debt redeemed with a refinancing are deferred, amortized, and recovered over the life of the replacement issue. • Customer360 deferred costs — The MPSC approved the deferral and amortization of certain costs associated with implementing Customer360, an integrated software application that enables improved interface among customer service, billing, meter reading, credit and collections, device management, account management, and retail access. Amortization of deferred costs over a 15 -year amortization period began after the billing system was put into operation during the second quarter of 2017. • Energy Waste Reduction incentive — DTE Electric and DTE Gas operate MPSC approved energy waste reduction programs designed to reduce overall energy usage by their customers. The utilities are eligible to earn an incentive by exceeding statutory savings targets. The utilities have consistently exceeded the savings targets and recognize the incentive as a regulatory asset in the period earned. (a) • Nuclear Performance Evaluation and Review Committee Tracker — Deferral and amortization of certain costs associated with oversight and review of DTE Electric's nuclear power generation program, including safety and regulatory compliance, nuclear leadership, nuclear facilities, as well as operation and financial performance, pursuant to the MPSC authorization. The approved five -year amortization period began January 1, 2018, with recovery through base rate filings. • Enhanced Tree Trimming Program deferred costs — The MPSC approved the deferral of costs for the first three years of a tree trimming surge, aimed at reducing the number and duration of customer interruptions. The MPSC will review the surge program and amortization of deferred costs in future rate filings. • Other recoverable income taxes — Income taxes receivable from DTE Electric's customers representing the difference in property-related deferred income taxes and amounts previously reflected in DTE Electric's rates. This asset will reverse over the remaining life of the related plant. • Non-service pension and other postretirement costs — Upon adoption of ASU 2017-07 on January 1, 2018, certain non-service costs are no longer capitalized into Property, Plant & Equipment. Such costs may be recorded to regulatory assets for ratemaking purposes and recovered as amortization expense based on the composite depreciation rate for plant-in-service. • Transitional Reconciliation Mechanism — The MPSC approved the recovery of the deferred net incremental revenue requirement associated with the transition of PLD customers to DTE Electric's distribution system, effective July 1, 2014. Annual reconciliations are filed and surcharges are implemented to recover approved amounts. • Accrued PSCR/GCR revenue — Receivable for the temporary under-recovery of and carrying costs on fuel and purchased power costs incurred by DTE Electric which are recoverable through the PSCR mechanism and temporary under-recovery of and carrying costs on gas costs incurred by DTE Gas which are recoverable through the GCR mechanism. • Removal costs asset — Receivable for the recovery of asset removal expenditures in excess of amounts collected from customers. (a) Cost of removal is included within depreciation rates approved by the MPSC. In connection with DTE Electric's recent rate order in 2019 which approved an updated depreciation study, DTE Electric re-measured the amount of historical depreciation expense that had been allocated between accumulated depreciation and cost of removal. The reallocation was performed following a settlement with the MPSC in which DTE Electric agreed to maintain specific, individual reserve accounts for the cost of removal for certain retiring plants. Based upon the reallocation, it was determined that the amounts collected for asset removal expenditures, as a component of depreciation, have exceeded actual asset removal expenditures. Accordingly, DTE Electric reallocated amounts from accumulated depreciation to the removal cost regulatory balance resulting in a net Removal costs liability as of December 31, 2019. ________________________________________________ (a) Regulatory assets not earning a return or accruing carrying charges. LIABILITIES • Refundable federal income taxes — DTE Electric and DTE Gas' remeasurement of deferred taxes due to the enactment of the TCJA, which reflects the net impact of the tax rate change on cumulative temporary differences expected to reverse after the effective date of January 1, 2018. Refer to "2017 Tax Reform" section below for additional information. • Removal costs liability — The amount collected from customers for the funding of future asset removal activities. For 2019, the liability includes amounts previously reflected within the Removal costs asset for DTE Electric, as noted above. • Negative other postretirement offset — DTE Electric and DTE Gas' negative other postretirement costs are not included as a reduction to their authorized rates; therefore, DTE Electric and DTE Gas are accruing a Regulatory liability to eliminate the impact on earnings of the negative other postretirement expense accrual. The Regulatory liabilities will reverse to the extent DTE Electric and DTE Gas' other postretirement expense is positive in future years. • Renewable energy — Amounts collected in rates in excess of renewable energy expenditures. • Non-service pension and other postretirement costs — Upon adoption of ASU 2017-07 on January 1, 2018, certain non-service cost activity is no longer credited to Property, Plant & Equipment. Such costs may be recorded to regulatory liabilities for ratemaking purposes and refunded through credits to amortization expense based on the composite depreciation rate for plant-in-service. • Accrued PSCR/GCR refund - Liability for the temporary over-recovery of and a return on power supply costs and transmission costs incurred by DTE Electric which are recoverable through the PSCR mechanism and temporary over-recovery of and a return on gas costs incurred by DTE Gas which are recoverable through the GCR mechanism. • TCJA rate reduction liability — Due to the change in the corporate Federal income tax rate from 35% to 21%, DTE Electric and DTE Gas reduced rates charged to customers during 2018. A regulatory liability equal to the difference between revenues billed based on a 35% rate, and revenues based on a 21% rate, was accrued for the period January 1, 2018 through the date the lower rates were implemented. The refund of the liability occurred from January 1, 2019 through June 30, 2019. 2018 Electric Rate Case Filing DTE Electric filed a rate case with the MPSC on July 6, 2018 requesting an increase in base rates of $328 million based on a projected twelve-month period ending April 30, 2020. The requested increase in base rates was primarily due to an increase in net plant resulting from infrastructure investments, depreciation expense, as requested in the 2016 DTE Electric Depreciation Case Filing, and reliability improvement projects. The rate filing also requested an increase in return on equity from 10.0% to 10.5% and included projected changes in sales, operation and maintenance expenses, and working capital. In addition, the rate filing requested an Infrastructure Recovery Mechanism to recover the incremental revenue requirement associated with certain distribution, fossil generation, and nuclear generation capital expenditures through 2022. Finally, as noted in the 2017 Tax Reform section below, DTE Electric proposed an amortization schedule for Calculation C in this filing. On February 1, 2019 DTE Electric reduced its initial requested increase in base rates to $248.6 million , primarily reflecting the reduction in requested depreciation expense resulting from the MPSC's approval of new depreciation rates. On May 2, 2019, the MPSC issued an order approving an annual revenue increase of $125 million for services rendered on or after May 9, 2019. The MPSC authorized a return on equity of 10.0% . In addition, the order approved the proposed amortization schedule for Calculation C but denied the requested Infrastructure Recovery Mechanism. 2019 Electric Rate Case Filing DTE Electric filed a rate case with the MPSC on July 8, 2019 requesting an increase in base rates of $351 million based on a projected twelve-month period ending April 30, 2021. The requested increase in base rates is primarily due to an increase in net plant resulting from infrastructure and generation investments. The rate filing also requests an increase in return on equity from 10.0% to 10.5% and includes projected changes in sales and operating and maintenance expenses. A final MPSC order in this case is expected by May 2020. 2016 DTE Electric Depreciation Case Filing DTE Electric filed a depreciation case with the MPSC on November 1, 2016 requesting an increase in depreciation rates for plant in service balances as of December 31, 2015. The MPSC issued an order on December 6, 2018 authorizing DTE Electric to increase its composite depreciation rate from 3.06% to 3.72% . The new rates are effective for service rendered on or after May 9, 2019, per the final order in DTE Electric's 2018 rate case issued on May 2, 2019. 2017 Tax Reform On December 27, 2017, the MPSC issued an order to consider changes in the rates of all Michigan rate-regulated utilities to reflect the effects of the federal TCJA. On January 19, 2018, DTE Electric and DTE Gas filed information with the MPSC regarding the potential change in revenue requirements due to the TCJA effective January 1, 2018 and outlined their recommended method to flow the current and deferred tax benefits of those impacts to ratepayers. On February 22, 2018, the MPSC issued an order in this case requiring utilities, including DTE Electric and DTE Gas, to follow a 3-step approach of credits and calculations. In 2018, MPSC orders for the first two steps, Credit A and Credit B, were issued for DTE Electric and DTE Gas. The third step is to perform Calculation C to address all remaining issues relative to the new tax law, which is primarily the remeasurement of deferred taxes and how the amounts deferred as Regulatory liabilities will flow to ratepayers. DTE Gas filed its Calculation C case on November 16, 2018 to reduce the annual revenue requirement by $12 million related to the amortization of deferred tax remeasurement. On August 20, 2019, the MPSC issued an order in this case approving a $13 million reduction to DTE Gas' annual revenue requirement. This reduction in revenue will be offset by a corresponding reduction in income tax expenses with the Consolidated Statement of Operations. DTE Electric proposed an amortization schedule for Calculation C in its general rate case filed July 6, 2018, which was approved by the MPSC in the May 2, 2019 rate order. 2019 Gas Rate Case Filing DTE Gas filed a rate case with the MPSC on November 25, 2019 requesting an increase in base rates of $204 million based on a projected twelve-month period ending September 30, 2021. The requested increase in base rates is primarily due to an increase in net plant resulting from infrastructure investments and operating and maintenance expenses. The rate filing also requests an increase in return on equity from 10.0% to 10.5% and includes projected changes in sales and working capital. A final MPSC order in this case is expected by September 2020.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES Income Tax Summary DTE Energy files a consolidated federal income tax return. DTE Electric is a part of the consolidated federal income tax return of DTE Energy. DTE Energy and its subsidiaries file consolidated and/or separate company income tax returns in various states and localities, including a consolidated return in the State of Michigan. DTE Electric is part of the Michigan consolidated income tax return of DTE Energy. The federal, state and local income tax expense for DTE Electric is determined on an individual company basis with no allocation of tax expenses or benefits from other affiliates of DTE Energy. DTE Electric had income tax receivables with DTE Energy of $14 million and $8 million at December 31, 2019 and 2018 , respectively. The Registrants' total Income Tax Expense varied from the statutory federal income tax rate for the following reasons: 2019 2018 2017 DTE Energy (In millions) Income Before Income Taxes $ 1,324 $ 1,216 $ 1,287 Income tax expense at statutory rate - 21% in 2019 and 2018 - 35% in 2017 $ 278 $ 255 $ 450 Production tax credits (128 ) (223 ) (189 ) Investment tax credits (4 ) (4 ) (4 ) TCJA regulatory liability amortization (38 ) — — Depreciation 2 2 (4 ) Noncontrolling interests — 2 8 AFUDC equity (4 ) (14 ) (18 ) Employee Stock Ownership Plan dividends (3 ) (3 ) (5 ) Stock based compensation (7 ) (3 ) (14 ) State and local income taxes, net of federal benefit 48 60 51 Enactment of the Tax Cuts and Jobs Act — 21 (105 ) Other, net 8 5 5 Income Tax Expense $ 152 $ 98 $ 175 Effective income tax rate 11.5 % 8.1 % 13.6 % 2019 2018 2017 DTE Electric (In millions) Income Before Income Taxes $ 854 $ 857 $ 928 Income tax expense at statutory rate - 21% in 2019 and 2018 - 35% in 2017 $ 179 $ 180 $ 325 Production tax credits (45 ) (35 ) (36 ) Investment tax credits (4 ) (3 ) (4 ) TCJA regulatory liability amortization (35 ) — — Depreciation 2 2 3 AFUDC equity (4 ) (3 ) (5 ) Employee Stock Ownership Plan dividends (2 ) (2 ) (3 ) State and local income taxes, net of federal benefit 49 49 48 Enactment of the Tax Cuts and Jobs Act — 7 — Other, net (2 ) (2 ) (1 ) Income Tax Expense $ 138 $ 193 $ 327 Effective income tax rate 16.2 % 22.5 % 35.2 % Components of the Registrants' Income Tax Expense were as follows: 2019 2018 2017 DTE Energy (In millions) Current income tax expense (benefit) Federal $ (184 ) $ (17 ) $ (22 ) State and other income tax 7 1 1 Total current income taxes (177 ) (16 ) (21 ) Deferred income tax expense Federal 275 38 118 State and other income tax 54 76 78 Total deferred income taxes 329 114 196 $ 152 $ 98 $ 175 2019 2018 2017 DTE Electric (In millions) Current income tax expense (benefit) Federal $ 25 $ — $ (17 ) State and other income tax 16 4 (1 ) Total current income taxes 41 4 (18 ) Deferred income tax expense Federal 51 131 270 State and other income tax 46 58 75 Total deferred income taxes 97 189 345 $ 138 $ 193 $ 327 Deferred tax assets and liabilities are recognized for the estimated future tax effect of temporary differences between the tax basis of assets or liabilities and the reported amounts in the Registrant's Consolidated Financial Statements. Consistent with the original establishment of these deferred tax liabilities (assets), recognition of these non-cash transactions are not reflected in the Consolidated Statements of Cash Flows. The Registrants' deferred tax assets (liabilities) were comprised of the following at December 31: DTE Energy DTE Electric 2019 2018 2019 2018 (In millions) Property, plant, and equipment $ (3,755 ) $ (3,462 ) $ (2,956 ) $ (2,840 ) Regulatory assets and liabilities (47 ) (54 ) 4 (3 ) Tax credit carry-forwards 1,161 1,178 252 250 Pension and benefits 300 311 258 258 Federal net operating loss carry-forward 276 117 — 2 State and local net operating loss carry-forwards 117 59 — 1 Investments in equity method investees (465 ) (216 ) — (1 ) Other 138 125 87 87 (2,275 ) (1,942 ) (2,355 ) (2,246 ) Less valuation allowance (40 ) (33 ) — — Long-term deferred income tax liabilities $ (2,315 ) $ (1,975 ) $ (2,355 ) $ (2,246 ) Deferred income tax assets $ 2,264 $ 2,021 $ 865 $ 855 Deferred income tax liabilities (4,579 ) (3,996 ) (3,220 ) (3,101 ) $ (2,315 ) $ (1,975 ) $ (2,355 ) $ (2,246 ) Tax credit carry-forwards for DTE Energy include $1.01 billion of general business credits that expire from 2034 through 2039 and $153 million of alternative minimum tax credits that will be refundable over the next three years . The alternative minimum tax credits are production tax credits earned prior to 2006 but not utilized. The majority of these alternative minimum tax credits were generated from projects that had received a private letter ruling (PLR) from the IRS. These PLRs provide assurance as to the appropriateness of using these credits to offset taxable income, however, these tax credits are subject to IRS audit and adjustment. No valuation allowance is required for the tax credits carry-forward deferred tax asset. DTE Energy has a federal net operating loss carry-forward of $1.3 billion as of December 31, 2019 . The net operating loss carry-forwards generated in 2015 and 2016 will expire from 2035 through 2036 , and the net operating loss carry-forward generated in 2018 and subsequent years will be carried forward indefinitely. No valuation allowance is required for the federal net operating loss deferred tax asset. DTE Energy has state and local deferred tax assets related to net operating loss carry-forwards of $117 million and $59 million at December 31, 2019 and 2018 , respectively. The state and local net operating loss carry-forwards expire from 2020 through 2039 . DTE Energy has recorded valuation allowances at December 31, 2019 and 2018 of approximately $40 million and $33 million , respectively, which are primarily related to these deferred tax assets. In assessing the realizability of deferred tax assets, DTE Energy considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. Tax credit carry-forwards for DTE Electric include $252 million of general business credits that expire from 2036 through 2039 . No valuation allowance is required for the tax credits carry-forward deferred tax asset. DTE Electric has no state and local deferred tax assets related to net operating loss carry-forwards at December 31, 2019 , while there was $1 million of state and local deferred tax assets related to net operating loss carry-forwards at December 31, 2018 . No valuation allowance is required for DTE Electric's state and local net operating loss carry-forwards. The above tables exclude unamortized investment tax credits that are shown separately on the Registrants' Consolidated Statements of Financial Position. Investment tax credits are deferred and amortized to income over the average life of the related property. Tax Cuts and Jobs Act On December 22, 2017, the TCJA was enacted reducing the corporate income tax rate from 35% to 21% , effective January 1, 2018. As a result of the enactment, the deferred tax assets and liabilities were remeasured to reflect the impact of the TCJA on the cumulative temporary differences expected to reverse after the effective date. The net impact of this remeasurement was a decrease in deferred tax liabilities of $2.56 billion , of which $2.45 billion was attributable to regulated utilities and offset to regulatory assets and liabilities. This regulatory treatment is consistent with prior precedent set by the MPSC from previous tax law changes. The remaining $105 million was attributable to the non-utility entities and was recognized as a net reduction to income tax expense in 2017. During the year ended December 31, 2018 , DTE Energy and DTE Electric finalized their analysis and recorded true-up adjustments to the remeasurement of deferred taxes of $21 million and $7 million , respectively. The impact of the true-up adjustments was an increase in Income Tax Expense, of which $17 million was attributable to the regulated utilities and increased Regulatory liabilities. During 2019, DTE Electric and DTE Gas began amortizing excess deferred tax liabilities in accordance with orders issued by the Michigan Public Service Commission. Refer to Note 10 to the Consolidated Financial Statements, "Regulatory Matters," for further detail regarding these orders. Uncertain Tax Positions A reconciliation of the beginning and ending amount of unrecognized tax benefits for the Registrants is as follows: 2019 2018 2017 DTE Energy (In millions) Balance at January 1 $ 10 $ 10 $ 10 Additions for tax positions of prior years — — — Balance at December 31 $ 10 $ 10 $ 10 2019 2018 2017 DTE Electric (In millions) Balance at January 1 $ 13 $ 13 $ 13 Additions for tax positions of prior years — — — Balance at December 31 $ 13 $ 13 $ 13 DTE Energy had $8 million of unrecognized tax benefits at December 31, 2019 and 2018 that, if recognized, would favorably impact its effective tax rate. DTE Energy does not anticipate any material decrease in unrecognized tax benefits in the next twelve months. DTE Electric had $10 million of unrecognized tax benefits at December 31, 2019 and 2018 that, if recognized, would favorably impact its effective tax rate. DTE Electric does not anticipate any material decrease in unrecognized tax benefits in the next twelve months. The Registrants recognize interest and penalties pertaining to income taxes in Interest expense and Other expenses, respectively, on their Consolidated Statements of Operations. Accrued interest pertaining to income taxes for DTE Energy totaled $4 million at December 31, 2019 and 2018 . DTE Energy recognized interest expense related to income taxes of $1 million in 2019 and 2018 , and a nominal amount in 2017 . DTE Energy had accrued no penalties pertaining to income taxes. Accrued interest pertaining to income taxes for DTE Electric totaled $6 million and $5 million at December 31, 2019 and 2018 , respectively. DTE Electric recognized interest expense related to income taxes of $1 million in 2019 and 2018 , and a nominal amount in 2017 . DTE Electric had accrued no penalties pertaining to income taxes. In 2019 , DTE Energy, including DTE Electric, settled a federal tax audit for the 2017 tax year. DTE Energy's federal income tax returns for 2018 and subsequent years remain subject to examination by the IRS. DTE Energy's Michigan Business Tax returns for the years 2008-2011 and Michigan Corporate Income Tax returns for the year 2015 and subsequent years remain subject to examination by the State of Michigan. DTE Energy also files tax returns in numerous state and local jurisdictions with varying statutes of limitation.

Common Stock and Earnings Per S

Common Stock and Earnings Per Share	12 Months Ended
	Dec. 31, 2019
Earnings Per Share [Abstract]
Common Stock and Earnings Per Share	COMMON STOCK AND EARNINGS PER SHARE Common Stock On October 1, 2019, DTE Energy issued approximately 5.87 million shares of common stock under the stock repurchase contracts associated with DTE Energy's 2016 Series C Equity Units for $675 million . Refer to Note 15 to the Consolidated Financial Statements, " Long-Term Debt " for additional information. In conjunction with the acquisition of Blue Union and LEAP, in November 2019 DTE Energy issued 2.76 million shares of common stock at $126.00 per share grossing $348 million . Net proceeds from the offering were approximately $339 million . Refer to Note 4 to the Consolidated Financial Statements, " Acquisitions " for additional information. Earnings per Share Basic earnings per share is calculated by dividing the net income, adjusted for income allocated to participating securities, by the weighted average number of common shares outstanding during the period. Diluted earnings per share reflect the dilution that would occur if any potentially dilutive instruments were exercised or converted into common shares. DTE Energy's participating securities are restricted shares under the stock incentive program that contain rights to receive non-forfeitable dividends. Equity units, performance shares, and stock options do not receive cash dividends; as such, these awards are not considered participating securities. For additional information, see Notes 15 and 22 to the Consolidated Financial Statements, " Long-Term Debt " and " Stock-Based Compensation ," respectively. The following is a reconciliation of DTE Energy's basic and diluted income per share calculation for the years ended December 31 : 2019 2018 2017 (In millions, except per share amounts) Basic Earnings per Share Net Income Attributable to DTE Energy Company $ 1,169 $ 1,120 $ 1,134 Less: Allocation of earnings to net restricted stock awards (2 ) (2 ) (2 ) Net income available to common shareholders — basic $ 1,167 $ 1,118 $ 1,132 Average number of common shares outstanding — basic 185 181 179 Basic Earnings per Common Share $ 6.32 $ 6.18 $ 6.32 Diluted Earnings per Share Net Income Attributable to DTE Energy Company $ 1,169 $ 1,120 $ 1,134 Less: Allocation of earnings to net restricted stock awards (2 ) (2 ) (2 ) Net income available to common shareholders — diluted $ 1,167 $ 1,118 $ 1,132 Average number of common shares outstanding - diluted 185 181 179 Diluted Earnings per Common Share (a) $ 6.31 $ 6.17 $ 6.32 _______________________________________ (a) Equity Units excluded from the calculation of diluted EPS were approximately 9.9 million for the year ended December 31, 2019 and 6.3 million for the years ended December 31, 2018 and 2017 , as the dilutive stock price threshold was not met. For more information, see Note 15 to the Consolidated Financial Statements, " Long-Term Debt ."

Fair Value

Fair Value	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value	FAIR VALUE Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date in a principal or most advantageous market. Fair value is a market-based measurement that is determined based on inputs, which refer broadly to assumptions that market participants use in pricing assets or liabilities. These inputs can be readily observable, market corroborated, or generally unobservable inputs. The Registrants make certain assumptions they believe that market participants would use in pricing assets or liabilities, including assumptions about risk, and the risks inherent in the inputs to valuation techniques. Credit risk of the Registrants and their counterparties is incorporated in the valuation of assets and liabilities through the use of credit reserves, the impact of which was immaterial at December 31, 2019 and 2018 . The Registrants believe they use valuation techniques that maximize the use of observable market-based inputs and minimize the use of unobservable inputs. A fair value hierarchy has been established that prioritizes the inputs to valuation techniques used to measure fair value in three broad levels. The fair value hierarchy gives the highest priority to quoted prices (unadjusted) in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3). In some cases, the inputs used to measure fair value might fall in different levels of the fair value hierarchy. All assets and liabilities are required to be classified in their entirety based on the lowest level of input that is significant to the fair value measurement in its entirety. Assessing the significance of a particular input may require judgment considering factors specific to the asset or liability and may affect the valuation of the asset or liability and its placement within the fair value hierarchy. The Registrants classify fair value balances based on the fair value hierarchy defined as follows: • Level 1 — Consists of unadjusted quoted prices in active markets for identical assets or liabilities that the Registrants have the ability to access as of the reporting date. • Level 2 — Consists of inputs other than quoted prices included within Level 1 that are directly observable for the asset or liability or indirectly observable through corroboration with observable market data. • Level 3 — Consists of unobservable inputs for assets or liabilities whose fair value is estimated based on internally developed models or methodologies using inputs that are generally less readily observable and supported by little, if any, market activity at the measurement date. Unobservable inputs are developed based on the best available information and subject to cost-benefit constraints. The following table presents assets and liabilities for DTE Energy measured and recorded at fair value on a recurring basis (a) : December 31, 2019 December 31, 2018 Level 1 Level 2 Level 3 Other (b) Netting (c) Net Balance Level 1 Level 2 Level 3 Other (b) Netting (c) Net Balance (In millions) Assets Cash equivalents (d) $ 15 $ — $ — $ — $ — $ 15 $ 16 $ 2 $ — $ — $ — $ 18 Nuclear decommissioning trusts Equity securities 1,046 — — — — 1,046 851 — — — — 851 Fixed income securities 160 378 — — — 538 12 490 — — — 502 Private equity and other — — — 43 — 43 — — — 20 — 20 Cash equivalents 34 — — — — 34 5 — — — — 5 Other investments (e) Equity securities 140 — — — — 140 110 — — — — 110 Fixed income securities 79 — — — — 79 69 — — — — 69 Cash equivalents 4 — — — — 4 4 — — — — 4 Derivative assets Commodity contracts Natural gas 205 76 74 — (266 ) 89 199 87 63 — (277 ) 72 Electricity — 223 83 — (225 ) 81 — 247 56 — (252 ) 51 Environmental & Other — 110 3 — (110 ) 3 — — 7 — (1 ) 6 Foreign currency exchange contracts — 1 — — — 1 — 4 — — — 4 Total derivative assets 205 410 160 — (601 ) 174 199 338 126 — (530 ) 133 Total $ 1,683 $ 788 $ 160 $ 43 $ (601 ) $ 2,073 $ 1,266 $ 830 $ 126 $ 20 $ (530 ) $ 1,712 Liabilities Derivative liabilities Commodity contracts Natural gas $ (221 ) $ (41 ) $ (89 ) $ — $ 266 $ (85 ) $ (197 ) $ (71 ) $ (112 ) $ — $ 272 $ (108 ) Electricity — (231 ) (67 ) — 225 (73 ) — (227 ) (58 ) — 240 (45 ) Environmental & Other — (121 ) — — 110 (11 ) — (1 ) — — 1 — Interest rate contracts — — — — — — — (3 ) — — — (3 ) Total $ (221 ) $ (393 ) $ (156 ) $ — $ 601 $ (169 ) $ (197 ) $ (302 ) $ (170 ) $ — $ 513 $ (156 ) Net Assets (Liabilities) at end of period $ 1,462 $ 395 $ 4 $ 43 $ — $ 1,904 $ 1,069 $ 528 $ (44 ) $ 20 $ (17 ) $ 1,556 Assets Current $ 218 $ 320 $ 123 $ — $ (513 ) $ 148 $ 212 $ 273 $ 96 $ — $ (461 ) $ 120 Noncurrent 1,465 468 37 43 (88 ) 1,925 1,054 557 30 20 (69 ) 1,592 Total Assets $ 1,683 $ 788 $ 160 $ 43 $ (601 ) $ 2,073 $ 1,266 $ 830 $ 126 $ 20 $ (530 ) $ 1,712 Liabilities Current $ (211 ) $ (300 ) $ (85 ) $ — $ 513 $ (83 ) $ (191 ) $ (251 ) $ (76 ) $ — $ 451 $ (67 ) Noncurrent (10 ) (93 ) (71 ) — 88 (86 ) (6 ) (51 ) (94 ) — 62 (89 ) Total Liabilities $ (221 ) $ (393 ) $ (156 ) $ — $ 601 $ (169 ) $ (197 ) $ (302 ) $ (170 ) $ — $ 513 $ (156 ) Net Assets (Liabilities) at end of period $ 1,462 $ 395 $ 4 $ 43 $ — $ 1,904 $ 1,069 $ 528 $ (44 ) $ 20 $ (17 ) $ 1,556 _______________________________________ (a) See footnotes on following page. _______________________________________ (b) Amounts represent assets valued at NAV as a practical expedient for fair value. (c) Amounts represent the impact of master netting agreements that allow DTE Energy to net gain and loss positions and cash collateral held or placed with the same counterparties. (d) At December 31, 2019 , the $15 million consisted of $4 million and $11 million of cash equivalents included in Cash and Cash equivalents and Other investments on DTE Energy's Consolidated Statements of Financial Position, respectively. At December 31, 2018 , the $18 million consisted of $3 million , $5 million , and $10 million of cash equivalents included in Cash and Cash equivalents, Restricted cash, and Other investments on DTE Energy's Consolidated Statements of Financial Position, respectively. (e) Excludes cash surrender value of life insurance investments. The following table presents assets for DTE Electric measured and recorded at fair value on a recurring basis as of: December 31, 2019 December 31, 2018 Level 1 Level 2 Level 3 Other (a) Net Balance Level 1 Level 2 Level 3 Other (a) Net Balance (In millions) Assets Cash equivalents (b) $ 11 $ — $ — $ — $ 11 $ 8 $ 2 $ — $ — $ 10 Nuclear decommissioning trusts Equity securities 1,046 — — — 1,046 851 — — — 851 Fixed income securities 160 378 — — 538 12 490 — — 502 Private equity and other — — — 43 43 — — — 20 20 Cash equivalents 34 — — — 34 5 — — — 5 Other investments Equity securities 13 — — — 13 10 — — — 10 Derivative assets — FTRs — — 3 — 3 — — 6 — 6 Total $ 1,264 $ 378 $ 3 $ 43 $ 1,688 $ 886 $ 492 $ 6 $ 20 $ 1,404 Assets Current $ 11 $ — $ 3 $ — $ 14 $ 8 $ 2 $ 6 $ — $ 16 Noncurrent 1,253 378 — 43 1,674 878 490 — 20 1,388 Total Assets $ 1,264 $ 378 $ 3 $ 43 $ 1,688 $ 886 $ 492 $ 6 $ 20 $ 1,404 _______________________________________ (a) Amounts represent assets valued at NAV as a practical expedient for fair value. (b) At December 31, 2019 , the $11 million consisted of cash equivalents included in Other investments on DTE Electric's Consolidated Statements of Financial Position. At December 31, 2018 , the $10 million consisted of cash equivalents included in Other investments on DTE Electric's Consolidated Statements of Financial Position. Cash Equivalents Cash equivalents include investments with maturities of three months or less when purchased. The cash equivalents shown in the fair value table are comprised of short-term investments and money market funds. Nuclear Decommissioning Trusts and Other Investments The nuclear decommissioning trusts and other investments hold debt and equity securities directly and indirectly through commingled funds. Exchange-traded debt and equity securities held directly are valued using quoted market prices in actively traded markets. Commingled funds that hold exchange-traded equity or debt securities are valued based on stated NAVs. Non-exchange traded fixed income securities are valued based upon quotations available from brokers or pricing services. Other assets such as private equity investments are classified as NAV assets. A primary price source is identified by asset type, class, or issue for each security. The trustee monitors prices supplied by pricing services and may use a supplemental price source or change the primary price source of a given security if the trustee determines that another price source is considered preferable. The Registrants have obtained an understanding of how these prices are derived, including the nature and observability of the inputs used in deriving such prices. Derivative Assets and Liabilities Derivative assets and liabilities are comprised of physical and financial derivative contracts, including futures, forwards, options, and swaps that are both exchange-traded and over-the-counter traded contracts. Various inputs are used to value derivatives depending on the type of contract and availability of market data. Exchange-traded derivative contracts are valued using quoted prices in active markets. The Registrants consider the following criteria in determining whether a market is considered active: frequency in which pricing information is updated, variability in pricing between sources or over time, and the availability of public information. Other derivative contracts are valued based upon a variety of inputs including commodity market prices, broker quotes, interest rates, credit ratings, default rates, market-based seasonality, and basis differential factors. The Registrants monitor the prices that are supplied by brokers and pricing services and may use a supplemental price source or change the primary price source of an index if prices become unavailable or another price source is determined to be more representative of fair value. The Registrants have obtained an understanding of how these prices are derived. Additionally, the Registrants selectively corroborate the fair value of their transactions by comparison of market-based price sources. Mathematical valuation models are used for derivatives for which external market data is not readily observable, such as contracts which extend beyond the actively traded reporting period. The Registrants have established a Risk Management Committee whose responsibilities include directly or indirectly ensuring all valuation methods are applied in accordance with predefined policies. The development and maintenance of the Registrants' forward price curves has been assigned to DTE Energy's Risk Management Department, which is separate and distinct from the trading functions within DTE Energy. The following table presents the fair value reconciliation of Level 3 assets and liabilities measured at fair value on a recurring basis for DTE Energy: Year Ended December 31, 2019 Year Ended December 31, 2018 Natural Gas Electricity Other Total Natural Gas Electricity Other Total (In millions) Net Assets (Liabilities) as of January 1 $ (49 ) $ (2 ) $ 7 $ (44 ) $ (29 ) $ 12 $ 8 $ (9 ) Transfers from Level 3 into Level 2 — — — — (3 ) — — (3 ) Total gains (losses) Included in earnings 15 77 (1 ) 91 (146 ) 29 1 (116 ) Recorded in Regulatory liabilities — — 2 2 — — 9 9 Purchases, issuances, and settlements: Settlements 19 (59 ) (5 ) (45 ) 129 (43 ) (11 ) 75 Net Assets (Liabilities) as of December 31 $ (15 ) $ 16 $ 3 $ 4 $ (49 ) $ (2 ) $ 7 $ (44 ) The amount of total gains (losses) included in Net Income attributed to the change in unrealized gains (losses) related to assets and liabilities held at December 31, 2019 and 2018 and reflected in Operating Revenues — Non-utility operations and Fuel, purchased power, and gas — non-utility in DTE Energy's Consolidated Statements of Operations $ (1 ) $ 59 $ (38 ) $ 20 $ (119 ) $ 15 $ (16 ) $ (120 ) The following table presents the fair value reconciliation of Level 3 assets and liabilities measured at fair value on a recurring basis for DTE Electric: Year Ended December 31, 2019 2018 (In millions) Net Assets as of January 1 $ 6 $ 9 Change in fair value recorded in Regulatory liabilities 2 9 Purchases, issuances, and settlements: Settlements (5 ) (12 ) Net Assets as of December 31 $ 3 $ 6 The amount of total gains (losses) included in Regulatory liabilities attributed to the change in unrealized gains (losses) related to assets and liabilities held at December 31, 2019 and 2018 and reflected in DTE Electric's Consolidated Statements of Financial Position $ 3 $ 6 Derivatives are transferred between levels primarily due to changes in the source data used to construct price curves as a result of changes in market liquidity. Transfers in and transfers out are reflected as if they had occurred at the beginning of the period. There were no transfers between Levels 1 and 2 for the Registrants during the years ended December 31, 2019 and 2018 , and there were no transfers from or into Level 3 for DTE Electric during the same periods. The following tables present the unobservable inputs related to DTE Energy's Level 3 assets and liabilities: December 31, 2019 Commodity Contracts Derivative Assets Derivative Liabilities Valuation Techniques Unobservable Input Range Weighted Average (In millions) Natural Gas $ 74 $ (89 ) Discounted Cash Flow Forward basis price (per MMBtu) $ (1.78 ) — $ 5.78 /MMBtu $ (0.09 )/MMBtu Electricity $ 83 $ (67 ) Discounted Cash Flow Forward basis price (per MWh) $ (10 ) — $ 6 /MWh $ — December 31, 2018 Commodity Contracts Derivative Assets Derivative Liabilities Valuation Techniques Unobservable Input Range Weighted Average (In millions) Natural Gas $ 63 $ (112 ) Discounted Cash Flow Forward basis price (per MMBtu) $ (2.15 ) — $ 5.59 /MMBtu $ (0.10 )/MMBtu Electricity $ 56 $ (58 ) Discounted Cash Flow Forward basis price (per MWh) $ (7 ) — $ 9 /MWh $ 1 /MWh The unobservable inputs used in the fair value measurement of the electricity and natural gas commodity types consist of inputs that are less observable due in part to lack of available broker quotes, supported by little, if any, market activity at the measurement date or are based on internally developed models. Certain basis prices (i.e., the difference in pricing between two locations) included in the valuation of natural gas and electricity contracts were deemed unobservable. The inputs listed above would have a direct impact on the fair values of the above security types if they were adjusted. A significant increase (decrease) in the basis price would result in a higher (lower) fair value for long positions, with offsetting impacts to short positions. Fair Value of Financial Instruments The following table presents the carrying amount and fair value of financial instruments for DTE Energy: December 31, 2019 December 31, 2018 Carrying Fair Value Carrying Fair Value Amount Level 1 Level 2 Level 3 Amount Level 1 Level 2 Level 3 (In millions) Notes receivable — Other (a) , excluding lessor finance leases $ 184 $ — $ — $ 184 $ 40 $ — $ — $ 40 Dividends payable $ 195 $ 195 $ — $ — $ 172 $ 172 $ — $ — Short-term borrowings $ 828 $ — $ 828 $ — $ 609 $ — $ 609 $ — Notes payable — Other (b) , excluding lessee finance leases $ 25 $ — $ — $ 25 $ 41 $ — $ — $ 41 Long-term debt (c) $ 16,606 $ 2,572 $ 14,207 $ 1,252 $ 13,622 $ 1,796 $ 10,712 $ 1,317 _______________________________________ (a) Current portion included in Current Assets — Other on DTE Energy's Consolidated Statements of Financial Position. (b) Included in Current Liabilities — Other and Other Liabilities — Other on DTE Energy's Consolidated Statements of Financial Position. (c) Includes debt due within one year, unamortized debt discounts, and issuance costs. Excludes finance lease obligations. The following table presents the carrying amount and fair value of financial instruments for DTE Electric: December 31, 2019 December 31, 2018 Carrying Fair Value Carrying Fair Value Amount Level 1 Level 2 Level 3 Amount Level 1 Level 2 Level 3 (In millions) Notes receivable — Other (a) , excluding lessor finance leases $ 9 $ — $ — $ 9 $ 6 $ — $ — $ 6 Short-term borrowings — affiliates $ 97 $ — $ — $ 97 $ 101 $ — $ — $ 101 Short-term borrowings — other $ 354 $ — $ 354 $ — 149 $ — $ 149 $ — Notes payable — Other (b) , excluding lessee finance leases $ 21 $ — $ — $ 21 $ 21 $ — $ — $ 21 Long-term debt (c) $ 7,180 $ — $ 7,916 $ 173 $ 6,538 $ — $ 6,552 $ 161 _______________________________________ (a) Included in Current Assets — Other on DTE Electric's Consolidated Statements of Financial Position. (b) Included in Current Liabilities — Other and Other Liabilities — Other on DTE Electric's Consolidated Statements of Financial Position. (c) Includes debt due within one year, unamortized debt discounts, and issuance costs. Excludes finance lease obligations. For further fair value information on financial and derivative instruments, see Note 14 to the Consolidated Financial Statements, " Financial and Other Derivative Instruments ." Nuclear Decommissioning Trust Funds DTE Electric has a legal obligation to decommission its nuclear power plants following the expiration of its operating licenses. This obligation is reflected as an Asset retirement obligation on DTE Electric's Consolidated Statements of Financial Position. Rates approved by the MPSC provide for the recovery of decommissioning costs of Fermi 2 and the disposal of low-level radioactive waste. See Note 9 to the Consolidated Financial Statements, " Asset Retirement Obligations ." The following table summarizes DTE Electric's fair value of the nuclear decommissioning trust fund assets: December 31, 2019 2018 (In millions) Fermi 2 $ 1,650 $ 1,372 Fermi 1 3 3 Low-level radioactive waste 8 3 $ 1,661 $ 1,378 The costs of securities sold are determined on the basis of specific identification. The following table sets forth DTE Electric's gains and losses and proceeds from the sale of securities by the nuclear decommissioning trust funds: Year Ended December 31, 2019 2018 2017 (In millions) Realized gains $ 56 $ 65 $ 83 Realized losses $ (31 ) $ (42 ) $ (29 ) Proceeds from sale of securities $ 788 $ 1,203 $ 1,240 Realized gains and losses from the sale of securities and unrealized gains and losses incurred by the Fermi 2 trust are recorded to the Regulatory asset and Nuclear decommissioning liability. Realized gains and losses from the sale of securities and unrealized gains and losses on the low-level radioactive waste funds are recorded to the Nuclear decommissioning liability. The following table sets forth DTE Electric's fair value and unrealized gains and losses for the nuclear decommissioning trust funds: December 31, 2019 December 31, 2018 Fair Unrealized Unrealized Losses Fair Unrealized Unrealized Losses (In millions) Equity securities $ 1,046 $ 396 $ (39 ) $ 851 $ 235 $ (79 ) Fixed income securities 538 24 (1 ) 502 7 (8 ) Private equity and other 43 — — 20 — — Cash equivalents 34 — — 5 — — $ 1,661 $ 420 $ (40 ) $ 1,378 $ 242 $ (87 ) The following table summarizes the fair value of the fixed income securities held in nuclear decommissioning trust funds by contractual maturity: December 31, 2019 (In millions) Due within one year $ 15 Due after one through five years 102 Due after five through ten years 109 Due after ten years 312 $ 538 Other Securities At December 31, 2019 and 2018 , the Registrants' securities, included in Other investments on the Consolidated Statements of Financial Position, were comprised primarily of money market and equity securities. Net gains related to equity securities held at December 31, 2019 were $37 million . Net losses related to equity securities held at December 31, 2018 were $11 million and net gains related to equity securities held at December 31, 2017 were $26 million . Gains or losses related to the Rabbi Trust assets are allocated from DTE Energy to DTE Electric.

Financial and Other Derivative

Financial and Other Derivative Instruments	12 Months Ended
	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Financial and Other Derivative Instruments	FINANCIAL AND OTHER DERIVATIVE INSTRUMENTS The Registrants recognize all derivatives at their fair value as Derivative assets or liabilities on their respective Consolidated Statements of Financial Position unless they qualify for certain scope exceptions, including the normal purchases and normal sales exception. Further, derivatives that qualify and are designated for hedge accounting are classified as either hedges of a forecasted transaction or the variability of cash flows to be received or paid related to a recognized asset or liability (cash flow hedge); or as hedges of the fair value of a recognized asset or liability or of an unrecognized firm commitment (fair value hedge). For cash flow hedges, the derivative gain or loss is deferred in Accumulated other comprehensive income (loss) and later reclassified into earnings when the underlying transaction occurs. For fair value hedges, changes in fair values for the derivative and hedged item are recognized in earnings each period. For derivatives that do not qualify or are not designated for hedge accounting, changes in fair value are recognized in earnings each period. The Registrants' primary market risk exposure is associated with commodity prices, credit, and interest rates. The Registrants have risk management policies to monitor and manage market risks. The Registrants use derivative instruments to manage some of the exposure. DTE Energy uses derivative instruments for trading purposes in its Energy Trading segment. Contracts classified as derivative instruments include electricity, natural gas, oil, certain environmental contracts, forwards, futures, options, swaps, and foreign currency exchange contracts. Items not classified as derivatives include natural gas and environmental inventory, pipeline transportation contracts, some environmental contracts, and natural gas storage assets. DTE Electric — DTE Electric generates, purchases, distributes, and sells electricity. DTE Electric uses forward contracts to manage changes in the price of electricity and fuel. Substantially all of these contracts meet the normal purchases and normal sales exception and are therefore accounted for under the accrual method. Other derivative contracts are MTM and recoverable through the PSCR mechanism when settled. This results in the deferral of unrealized gains and losses as Regulatory assets or liabilities until realized. DTE Gas — DTE Gas purchases, stores, transports, distributes, and sells natural gas, buys and sells transportation capacity, and sells storage capacity. DTE Gas has fixed-priced contracts for portions of its expected natural gas supply requirements through March 2022. Substantially all of these contracts meet the normal purchases and normal sales exception and are therefore accounted for under the accrual method. DTE Gas may also sell forward transportation and storage capacity contracts. Forward transportation and storage contracts are generally not derivatives and are therefore accounted for under the accrual method. Gas Storage and Pipelines — This segment is primarily engaged in services related to the gathering, transportation, and storage of natural gas. Primarily fixed-priced contracts are used in the marketing and management of transportation and storage services. Generally, these contracts are not derivatives and are therefore accounted for under the accrual method. Power and Industrial Projects — This segment manages and operates energy and pulverized coal projects, a coke battery, reduced emissions fuel projects, renewable gas recovery, and power generation assets. Primarily fixed-price contracts are used in the marketing and management of the segment assets. These contracts are generally not derivatives and are therefore accounted for under the accrual method. Energy Trading — Commodity Price Risk — Energy Trading markets and trades electricity, natural gas physical products, and energy financial instruments, and provides energy and asset management services utilizing energy commodity derivative instruments. Forwards, futures, options, and swap agreements are used to manage exposure to the risk of market price and volume fluctuations in its operations. These derivatives are accounted for by recording changes in fair value to earnings unless hedge accounting criteria are met. Energy Trading — Foreign Currency Exchange Risk — Energy Trading has foreign currency exchange forward contracts to economically hedge fixed Canadian dollar commitments existing under natural gas and power purchase and sale contracts and natural gas transportation contracts. Energy Trading enters into these contracts to mitigate price volatility with respect to fluctuations of the Canadian dollar relative to the U.S. dollar. These derivatives are accounted for by recording changes in fair value to earnings unless hedge accounting criteria are met. Corporate and Other — Interest Rate Risk — DTE Energy may use interest rate swaps, treasury locks, and other derivatives to hedge the risk associated with interest rate market volatility. Credit Risk — DTE Energy maintains credit policies that significantly minimize overall credit risk. These policies include an evaluation of potential customers’ and counterparties’ financial condition, including the viability of underlying productive assets, credit rating, collateral requirements, or other credit enhancements such as letters of credit or guarantees. DTE Energy generally uses standardized agreements that allow the netting of positive and negative transactions associated with a single counterparty. DTE Energy maintains a provision for credit losses based on factors surrounding the credit risk of its customers, historical trends, and other information. Based on DTE Energy's credit policies and its December 31, 2019 provision for credit losses, DTE Energy’s exposure to counterparty nonperformance is not expected to have a material adverse effect on DTE Energy's Consolidated Financial Statements. Derivative Activities DTE Energy manages its MTM risk on a portfolio basis based upon the delivery period of its contracts and the individual components of the risks within each contract. Accordingly, it records and manages the energy purchase and sale obligations under its contracts in separate components based on the commodity (e.g. electricity or natural gas), the product (e.g. electricity for delivery during peak or off-peak hours), the delivery location (e.g. by region), the risk profile (e.g. forward or option), and the delivery period (e.g. by month and year). The following describes the categories of activities represented by their operating characteristics and key risks: • Asset Optimization — Represents derivative activity associated with assets owned and contracted by DTE Energy, including forward natural gas purchases and sales, natural gas transportation, and storage capacity. Changes in the value of derivatives in this category typically economically offset changes in the value of underlying non-derivative positions, which do not qualify for fair value accounting. The difference in accounting treatment of derivatives in this category and the underlying non-derivative positions can result in significant earnings volatility. • Marketing and Origination — Represents derivative activity transacted by originating substantially hedged positions with wholesale energy marketers, producers, end-users, utilities, retail aggregators, and alternative energy suppliers. • Fundamentals Based Trading — Represents derivative activity transacted with the intent of taking a view, capturing market price changes, or putting capital at risk. This activity is speculative in nature as opposed to hedging an existing exposure. • Other — Includes derivative activity at DTE Electric related to FTRs. Changes in the value of derivative contracts at DTE Electric are recorded as Derivative assets or liabilities, with an offset to Regulatory assets or liabilities as the settlement value of these contracts will be included in the PSCR mechanism when realized. The following table presents the fair value of derivative instruments for DTE Energy: December 31, 2019 December 31, 2018 Derivative Derivative Derivative Derivative (In millions) Derivatives designated as hedging instruments Interest rate contracts $ — $ — $ — $ (3 ) Derivatives not designated as hedging instruments Commodity contracts Natural gas $ 355 $ (351 ) $ 349 $ (380 ) Electricity 306 (298 ) 303 (285 ) Environmental & Other 113 (121 ) 7 (1 ) Foreign currency exchange contracts 1 — 4 — Total derivatives not designated as hedging instruments $ 775 $ (770 ) $ 663 $ (666 ) Current $ 646 $ (596 ) $ 563 $ (518 ) Noncurrent 129 (174 ) 100 (151 ) Total derivatives $ 775 $ (770 ) $ 663 $ (669 ) The following table presents the fair value of derivative instruments for DTE Electric: December 31, 2019 2018 (In millions) FTRs — Other current assets $ 3 $ 6 Total derivatives not designated as hedging instruments $ 3 $ 6 Certain of DTE Energy's derivative positions are subject to netting arrangements which provide for offsetting of asset and liability positions as well as related cash collateral. Such netting arrangements generally do not have restrictions. Under such netting arrangements, DTE Energy offsets the fair value of derivative instruments with cash collateral received or paid for those contracts executed with the same counterparty, which reduces DTE Energy's Total Assets and Liabilities. Cash collateral is allocated between the fair value of derivative instruments and customer accounts receivable and payable with the same counterparty on a pro-rata basis to the extent there is exposure. Any cash collateral remaining, after the exposure is netted to zero, is reflected in Accounts receivable and Accounts payable as collateral paid or received, respectively. DTE Energy also provides and receives collateral in the form of letters of credit which can be offset against net Derivative assets and liabilities as well as Accounts receivable and payable. DTE Energy had issued letters of credit of $6 million outstanding at December 31, 2019 and $4 million at December 31, 2018 , which could be used to offset net Derivative liabilities. Letters of credit received from third parties which could be used to offset net Derivative assets were $4 million and $8 million at December 31, 2019 and 2018 , respectively. Such balances of letters of credit are excluded from the tables below and are not netted with the recognized assets and liabilities in DTE Energy's Consolidated Statements of Financial Position. For contracts with certain clearing agents, the fair value of derivative instruments is netted against realized positions with the net balance reflected as either 1) a Derivative asset or liability or 2) an Account receivable or payable. Other than certain clearing agents, Accounts receivable and Accounts payable that are subject to netting arrangements have not been offset against the fair value of Derivative assets and liabilities. The following table presents net cash collateral offsetting arrangements for DTE Energy: December 31, 2019 2018 (In millions) Cash collateral netted against Derivative assets $ — $ (17 ) Cash collateral recorded in Accounts receivable (a) 13 10 Cash collateral recorded in Accounts payable (a) (3 ) (6 ) Total net cash collateral posted (received) $ 10 $ (13 ) _______________________________________ (a) Amounts are recorded net by counterparty. The following table presents the netting offsets of Derivative assets and liabilities for DTE Energy: December 31, 2019 December 31, 2018 Gross Amounts of Recognized Assets (Liabilities) Gross Amounts Offset in the Consolidated Statements of Financial Position Net Amounts of Assets (Liabilities) Presented in the Consolidated Statements of Financial Position Gross Amounts of Recognized Assets (Liabilities) Gross Amounts Offset in the Consolidated Statements of Financial Position Net Amounts of Assets (Liabilities) Presented in the Consolidated Statements of Financial Position (In millions) Derivative assets Commodity contracts Natural gas $ 355 $ (266 ) $ 89 $ 349 $ (277 ) $ 72 Electricity 306 (225 ) 81 303 (252 ) 51 Environmental & Other 113 (110 ) 3 7 (1 ) 6 Foreign currency exchange contracts 1 — 1 4 — 4 Total derivative assets $ 775 $ (601 ) $ 174 $ 663 $ (530 ) $ 133 Derivative liabilities Commodity contracts Natural gas $ (351 ) $ 266 $ (85 ) $ (380 ) $ 272 $ (108 ) Electricity (298 ) 225 (73 ) (285 ) 240 (45 ) Environmental & Other (121 ) 110 (11 ) (1 ) 1 — Interest rate contracts — — — (3 ) — (3 ) Total derivative liabilities $ (770 ) $ 601 $ (169 ) $ (669 ) $ 513 $ (156 ) The following table presents the netting offsets of Derivative assets and liabilities showing the reconciliation of derivative instruments to DTE Energy's Consolidated Statements of Financial Position: December 31, 2019 December 31, 2018 Derivative Assets Derivative Liabilities Derivative Assets Derivative Liabilities Current Noncurrent Current Noncurrent Current Noncurrent Current Noncurrent (In millions) Total fair value of derivatives $ 646 $ 129 $ (596 ) $ (174 ) $ 563 $ 100 $ (518 ) $ (151 ) Counterparty netting (513 ) (88 ) 513 88 (451 ) (62 ) 451 62 Collateral adjustment — — — — (10 ) (7 ) — — Total derivatives as reported $ 133 $ 41 $ (83 ) $ (86 ) $ 102 $ 31 $ (67 ) $ (89 ) The effect of derivatives not designated as hedging instruments on DTE Energy's Consolidated Statements of Operations is as follows: Location of Gain (Loss) Recognized in Income on Derivatives Gain (Loss) Recognized in Income on Derivatives for Years Ended December 31, 2019 2018 2017 (In millions) Commodity contracts Natural gas Operating Revenues — Non-utility operations $ 44 $ (42 ) $ (74 ) Natural gas Fuel, purchased power, and gas — non-utility (5 ) (94 ) 97 Electricity Operating Revenues — Non-utility operations 44 49 105 Environmental & Other Operating Revenues — Non-utility operations (26 ) (1 ) 2 Foreign currency exchange contracts Operating Revenues — Non-utility operations (2 ) 7 (2 ) Total $ 55 $ (81 ) $ 128 Revenues and energy costs related to trading contracts are presented on a net basis in DTE Energy's Consolidated Statements of Operations. Commodity derivatives used for trading purposes, and financial non-trading commodity derivatives, are accounted for using the MTM method with unrealized and realized gains and losses recorded in Operating Revenues — Non-utility operations. Non-trading physical commodity sale and purchase derivative contracts are generally accounted for using the MTM method with unrealized and realized gains and losses for sales recorded in Operating Revenues — Non-utility operations and purchases recorded in Fuel, purchased power, and gas — non-utility. The following represents the cumulative gross volume of DTE Energy's derivative contracts outstanding as of December 31, 2019 : Commodity Number of Units Natural gas (MMBtu) 1,699,804,805 Electricity (MWh) 31,351,229 Foreign currency exchange (CAD) 78,563,487 Various subsidiaries of DTE Energy have entered into contracts which contain ratings triggers and are guaranteed by DTE Energy. These contracts contain provisions which allow the counterparties to require that DTE Energy post cash or letters of credit as collateral in the event that DTE Energy’s credit rating is downgraded below investment grade. Certain of these provisions (known as "hard triggers") state specific circumstances under which DTE Energy can be required to post collateral upon the occurrence of a credit downgrade, while other provisions (known as "soft triggers") are not as specific. For contracts with soft triggers, it is difficult to estimate the amount of collateral which may be requested by counterparties and/or which DTE Energy may ultimately be required to post. The amount of such collateral which could be requested fluctuates based on commodity prices (primarily natural gas, power, and coal) and the provisions and maturities of the underlying transactions. As of December 31, 2019 , DTE Energy's contractual obligation to post collateral in the form of cash or letters of credit in the event of a downgrade to below investment grade, under both hard trigger and soft trigger provisions, was $527 million . As of December 31, 2019 , DTE Energy had $678 million of derivatives in net liability positions, for which hard triggers exist. There is no collateral that has been posted against such liabilities, including cash and letters of credit. Associated derivative net asset positions for which contractual offset exists were $593 million . The net remaining amount of $85 million is derived from the $527 million noted above.

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2019
Long-term Debt, Unclassified [Abstract]
Long-Term Debt	LONG-TERM DEBT Long-Term Debt DTE Energy's long-term debt outstanding and weighted average interest rates of debt outstanding at December 31 were: Interest Rate (a) Maturity Date 2019 2018 (In millions) Mortgage bonds, notes, and other DTE Energy Debt, Unsecured 3.2% 2022 — 2033 $ 6,625 $ 4,425 DTE Electric Taxable Debt, Principally Secured 4.2% 2020 — 2049 6,930 6,280 DTE Electric Tax-Exempt Revenue Bonds (b) 4.3% 2020 — 2030 310 310 DTE Gas Taxable Debt, Principally Secured 4.3% 2020 — 2049 1,710 1,550 Other Long-Term Debt, including Non-Recourse Debt — 1 15,575 12,566 Unamortized debt discount (24 ) (16 ) Unamortized debt issuance costs (91 ) (73 ) Long-term debt due within one year (682 ) (1,495 ) $ 14,778 $ 10,982 Junior Subordinated Debentures Subordinated Debentures 5.5% 2062 — 2077 $ 1,180 $ 1,180 Unamortized debt issuance costs (34 ) (35 ) $ 1,146 $ 1,145 _______________________________________ (a) Weighted average interest rate as of December 31, 2019 . (b) DTE Electric Tax-Exempt Revenue Bonds are issued by a public body that loans the proceeds to DTE Electric on terms substantially mirroring the Revenue Bonds. DTE Electric's long-term debt outstanding and weighted average interest rates of debt outstanding at December 31 were: Interest Rate (a) Maturity Date 2019 2018 (In millions) Mortgage bonds, notes, and other Taxable Debt, Principally Secured 4.2% 2020 — 2049 $ 6,930 $ 6,280 Tax-Exempt Revenue Bonds (b) 4.3% 2020 — 2030 310 310 7,240 6,590 Unamortized debt discount (15 ) (11 ) Unamortized debt issuance costs (45 ) (41 ) Long-term debt due within one year (632 ) — $ 6,548 $ 6,538 _______________________________________ (a) Weighted average interest rate as of December 31, 2019 . (b) Tax-Exempt Revenue Bonds are issued by a public body that loans the proceeds to DTE Electric on terms substantially mirroring the Revenue Bonds. Debt Issuances In 2019 , the following debt was issued: Company Month Type Interest Rate Maturity Date Amount (In millions) DTE Electric February Mortgage Bonds (a) 3.95% 2049 $ 650 DTE Energy June Senior Notes (b) 2.60% 2022 300 DTE Energy June Senior Notes (b) 3.40% 2029 500 DTE Gas October Mortgage Bonds (b) 2.95% 2029 140 DTE Gas October Mortgage Bonds (b) 3.72% 2049 140 DTE Energy November Senior Notes (c) 2.25% 2022 500 DTE Energy November Senior Notes (c) 2.95% 2030 300 DTE Energy November Equity Units (c) (d) 2025 1,300 $ 3,830 _______________________________________ (a) Bonds were issued as Green Bonds and the proceeds will be used to finance expenditures for solar and wind energy, payments under power purchase agreements for solar and wind energy, and energy optimization programs. (b) Proceeds were used for the repayment of short-term borrowings and general corporate purposes. (c) Proceeds were used to pay a portion of the purchase price of the Blue Union and LEAP acquisition. Refer to "Acquisition Financing" below for additional information. (d) See "Acquisition Financing" below for more information regarding the rates associated with the Equity Units. Debt Redemptions In 2019 , the following debt was redeemed: Company Month Type Interest Rate Maturity Date Amount (In millions) DTE Energy October Senior Notes 1.50% 2019 $ 400 DTE Gas October Senior Notes 5.00% 2019 120 DTE Energy December Senior Notes 2.40% 2019 300 DTE Energy Various Other long-term debt Various 2019 1 $ 821 The following table shows the Registrants' scheduled debt maturities, excluding any unamortized discount on debt: 2020 2021 2022 2023 2024 2025 and Thereafter Total (In millions) DTE Energy (a) $ 682 $ 462 $ 2,716 $ 1,177 $ 1,425 $ 10,293 $ 16,755 DTE Electric $ 632 $ 462 $ 316 $ 202 $ 400 $ 5,228 $ 7,240 _______________________________________ (a) Amounts include DTE Electric's scheduled debt maturities. In January 2020, DTE Electric sent notice to optionally redeem its $300 million 2010 Series A 4.89% Senior Notes due September 2020. The notes are expected to be redeemed in March 2020. Junior Subordinated Debentures DTE Energy has the right to defer interest payments on the Junior Subordinated Debentures. Should DTE Energy exercise this right, it cannot declare or pay dividends on, or redeem, purchase or acquire, any of its capital stock during the deferral period. Any deferred interest payments will bear additional interest at the rate associated with the related debt issue. As of December 31, 2019 , no interest payments have been deferred on the Junior Subordinated Debentures. Cross Default Provisions Substantially all of the net utility properties of DTE Electric and DTE Gas are subject to the lien of mortgages. Should DTE Electric or DTE Gas fail to timely pay their indebtedness under these mortgages, such failure may create cross defaults in the indebtedness of DTE Energy. 2016 Acquisition Senior Notes Remarketing In October 2016, DTE Energy issued $675 million of 2016 Equity Units, initially in the form of Corporate Units. The Corporate Units were listed on the New York Stock Exchange under the symbol DTV. Each Corporate Unit consisted of a stock purchase contract and a 1/20 interest in a RSN issued by DTE Energy. The stock purchase contract obligated the holders to purchase shares of DTE Energy's common stock at a future settlement date. The purchase price under the stock purchase contracts was $50 per Corporate Unit and the number of shares purchased was determined by a formula based upon the average closing price of DTE Energy common stock near the settlement date. The RSNs were pledged as collateral to secure the purchase of common stock under the related stock purchase contracts. In August 2019, DTE Energy remarketed the $675 million 2016 Series C 1.5% RSNs due 2024 pursuant to the terms of the 2016 Equity Units. As a result of the remarketing, the interest rate was reset to 2.529% , payable semi-annually at the new rate beginning October 1, 2019. DTE Energy did not receive any proceeds from the remarketing. All proceeds belonged to the investors holding the related 2016 Equity Units and were temporarily used to purchase a portfolio of treasury securities. The securities were released on behalf of investors on October 1, 2019 to satisfy the related stock purchase contracts and pay the purchase price to DTE Energy for the issuance of approximately 5.87 million shares of common stock. Gas Storage and Pipelines Segment Acquisition Financing In December 2019, DTE Energy closed on the purchase of midstream natural gas assets. The acquisition was financed through the issuance of Equity Units, Senior Notes, and common stock. For information on the common stock issuance, refer to Note 12 to the Consolidated Financial Statements, " Common Stock and Earnings Per Share ." In November 2019, DTE issued $1.3 billion of 2019 Equity Units. Each Equity Unit has a stated amount of $ 50 and was initially issued in the form of a Corporate Unit, comprised of (i) a forward purchase contract to buy DTE Energy common stock (stock purchase contract) and (ii) a 1/20 undivided beneficial ownership interest in $1,000 principal amount of DTE Energy’s 2019 Series F 2.25% RSNs due 2025 . The RSN debt instruments and the stock purchase contract equity instruments are deemed to be separate instruments as the investor may trade the RSNs separately from the stock purchase contracts and may also settle the stock purchase contracts separately. The Corporate Units are listed on the New York Stock Exchange under the symbol DTP. The stock purchase contract obligates the holder to purchase from DTE Energy on the settlement date, November 1, 2022, for a price of $ 50 per stock purchase contract, the following number of shares of DTE Energy’s common stock, subject to anti-dilution adjustments: • if the AMV of DTE Energy’s common stock, which is the average volume-weighted average price of DTE Energy’s common stock for the trading days during the 20 consecutive scheduled trading day period ending on the third scheduled trading day immediately preceding the stock purchase contract settlement date, is equal to or greater than $157.50 , 0.3175 shares of common stock; • if the AMV is less than $157.50 but greater than $ 126.00 , a number of shares of common stock equal to $50 divided by the AMV; and • if the AMV is less than or equal to $126.00 , 0.3968 shares of common stock. The RSNs bear interest at a rate of 2.25% per year, payable quarterly, and mature on November 1, 2025 . The RSNs will be remarketed in 2022. If this remarketing is successful, the interest rate on the RSNs will be reset, and thereafter interest will be payable semi-annually at the reset rate. If there is no successful remarketing, the interest rate on the RSNs will not be reset, and the holders of the RSNs will have the right to put the RSNs to DTE Energy at a price equal to 100% of the principal amount, and the proceeds of the put right will be deemed to have been applied against the holders’ obligation under the stock purchase contracts. DTE Energy may also redeem, in whole or in part, the RSNs in the event of a failed final remarketing. DTE Energy will also pay the stock purchase contract holders quarterly contract adjustment payments at a rate of 4% per year of the stated amount of $50 per Equity Unit, or $2 per year, commencing on February 1, 2020 . The present value of the future contract adjustment payments of $150 million is recorded as a reduction of shareholders’ equity, offset by the stock purchase contract liability. The stock purchase contract liability is included in Current Liabilities — Other and Other Liabilities — Other on DTE Energy’s Consolidated Statements of Financial Position. Interest payments on the RSNs are recorded as interest expense and stock purchase contract payments are charged against the liability. Accretion of the stock purchase contract liability is recorded as imputed interest expense. The treasury stock method will be used to compute diluted EPS for the stock purchase contract. Under the treasury stock method, the stock purchase contract will only have a dilutive effect when the settlement rate is based on the market value of DTE’s common stock that is greater than $157.50 (the threshold appreciation price). If payments for the stock purchase contract are deferred, DTE Energy may not make any cash distributions related to its capital stock, including dividends, redemptions, repurchases, liquidation payments or guarantee payments. Also, during the deferral period, DTE Energy may not make any payments on or redeem or repurchase any debt securities that are equal in right of payment with, or subordinated to, the RSNs. Until settlement of the stock purchase contracts, the shares of stock underlying each contract are not outstanding. Under the terms of the stock purchase contracts, assuming no anti-dilution or other adjustments, DTE Energy will issue between 8.3 million and 10.3 million shares of its common stock in November 2022. A total of 13 million shares of DTE Energy’s common stock have been reserved for issuance in connection with the stock purchase contracts. Selected information about DTE Energy’s 2019 Equity Units is presented below: Issuance Date Units Issued Total Net Proceeds Total Long-Term Debt RSN Annual Interest Rate Stock Purchase Contract Annual Rate Stock Purchase Settlement Date Stock Purchase Contract Liability RSN Maturity Date (In millions, except interest rates) 11/1/19 26 $ 1,268 $ 1,300 2.25% 4.0% 11/1/2022 $ 150 11/1/2025 In November 2019, DTE Energy issued $500 million of 2019 Series G 2.25% Senior Notes due 2022 and $300 million of Series H 2.95% Senior Notes due 2030. The proceeds from the Senior Notes were used for the acquisition.

Preferred and Preference Securi

Preferred and Preference Securities	12 Months Ended
	Dec. 31, 2019
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred and Preference Securities	PREFERRED AND PREFERENCE SECURITIES As of December 31, 2019 , the amount of authorized and unissued stock is as follows: Company Type of Stock Par Value Shares Authorized DTE Energy Preferred $ — 5,000,000 DTE Electric Preferred $ 100 6,747,484 DTE Electric Preference $ 1 30,000,000 DTE Gas Preferred $ 1 7,000,000 DTE Gas Preference $ 1 4,000,000

Short-Term Credit Arrangements

Short-Term Credit Arrangements and Borrowings	12 Months Ended
	Dec. 31, 2019
Short-term Debt [Abstract]
Short-Term Credit Arrangements and Borrowings	SHORT-TERM CREDIT ARRANGEMENTS AND BORROWINGS DTE Energy, DTE Electric, and DTE Gas have unsecured revolving credit agreements that can be used for general corporate borrowings, but are intended to provide liquidity support for each of the companies’ commercial paper programs. Borrowings under the revolvers are available at prevailing short-term interest rates. Additionally, DTE Energy has other facilities to support letter of credit issuance. The agreements require DTE Energy, DTE Electric, and DTE Gas to maintain a total funded debt to capitalization ratio of no more than 0.65 to 1. In the agreements, "total funded debt" means all indebtedness of each respective company and their consolidated subsidiaries, including finance lease obligations, hedge agreements, and guarantees of third parties’ debt, but excluding contingent obligations, nonrecourse and junior subordinated debt, and certain equity-linked securities and, except for calculations at the end of the second quarter, certain DTE Gas short-term debt. "Capitalization" means the sum of (a) total funded debt plus (b) "consolidated net worth," which is equal to consolidated total equity of each respective company and their consolidated subsidiaries (excluding pension effects under certain FASB statements), as determined in accordance with accounting principles generally accepted in the United States of America. At December 31, 2019 , the total funded debt to total capitalization ratios for DTE Energy, DTE Electric, and DTE Gas were 0.58 to 1, 0.51 to 1, and 0.48 to 1, respectively, and were in compliance with this financial covenant. The availability under the facilities in place at December 31, 2019 is shown in the following table: DTE Energy DTE Electric DTE Gas Total (In millions) Unsecured letter of credit facility, expiring in February 2021 $ 150 $ — $ — $ 150 Unsecured letter of credit facility, expiring in August 2021 110 — — 110 Unsecured revolving credit facility, expiring April 2024 1,500 500 300 2,300 1,760 500 300 2,560 Amounts outstanding at December 31, 2019 Commercial paper issuances 280 354 194 828 Letters of credit 229 — — 229 509 354 194 1,057 Net availability at December 31, 2019 $ 1,251 $ 146 $ 106 $ 1,503 DTE Energy has $9 million of other outstanding letters of credit which are used for various corporate purposes and are not included in the facilities described above. The weighted average interest rate for short-term borrowings was 2.0% and 2.9% at December 31, 2019 and 2018 , respectively, for DTE Energy. The weighted average interest rate for short-term borrowings was 1.9% and 2.9% at December 31, 2019 and 2018 , respectively, for DTE Electric. In conjunction with maintaining certain exchange-traded risk management positions, DTE Energy may be required to post collateral with its clearing agent. DTE Energy has a demand financing agreement for up to $100 million with its clearing agent. The agreement, as amended, also allows for up to $50 million of additional margin financing provided that DTE Energy posts a letter of credit for the incremental amount and allows the right of setoff with posted collateral. At December 31, 2019 , the capacity under this facility was $150 million . The amount outstanding under this agreement was $114 million and $93 million at December 31, 2019 and 2018 , respectively, and was fully offset by the posted collateral. Dividend Restrictions Certain of DTE Energy’s credit facilities contain a provision requiring DTE Energy to maintain a total funded debt to capitalization ratio, as defined in the agreements, of no more than 0.65 to 1, which has the effect of limiting the amount of dividends DTE Energy can pay in order to maintain compliance with this provision. At December 31, 2019 , the effect of this provision was to restrict the payment of approximately $3.2 billion of Retained earnings totaling $6.6 billion . There are no other effective limitations with respect to DTE Energy’s ability to pay dividends.

Leases

Leases	12 Months Ended
	Dec. 31, 2019
Leases [Abstract]
Leases	LEASES Disclosures related to the year ended December 31, 2019 are presented as required under Topic 842. Prior period disclosures for the year ended December 31, 2018 are presented under Topic 840. The Registrants have elected to use a practical expedient provided by Topic 842 whereby comparative disclosures for prior periods are allowed to be presented under Topic 840. As a result, the disclosures presented under Topic 842 and Topic 840 will not be fully comparable in specific disclosure requirements. Lessee Topic 842 — Leases at DTE Energy are primarily comprised of various forms of equipment, computer hardware, coal railcars, production facilities, buildings, and certain easement leases with terms ranging from approximately 2 to 40 years. Leases at DTE Electric are primarily comprised of various forms of equipment, computer hardware, coal railcars, and certain easement leases with terms ranging from approximately 2 to 40 years. A lease is deemed to exist when the Registrants have the right to control the use of identified property, plant or equipment, as conveyed through a contract, for a certain period of time and consideration paid. The right to control is deemed to occur when the Registrants have the right to obtain substantially all of the economic benefits of the identified assets and the right to direct the use of such assets. Lease liabilities are determined utilizing a discount rate to determine the present values of lease payments. Topic 842 requires the use of the rate implicit in the lease when it is readily determinable. When the rate implicit in the lease is not readily determinable, the incremental borrowing rate is used. The Registrants have determined their respective incremental borrowing rates based upon the rate of interest that would have been paid on a collateralized basis over similar tenors to that of the leases. The incremental borrowing rates for DTE Electric and DTE Gas have been determined utilizing respective secured borrowing rates for first mortgage bonds with like tenors of remaining lease terms. Incremental borrowing rates for non-utility entities have been determined utilizing an implied secured borrowing rate based upon an unsecured rate for a similar tenor of remaining lease terms, which is then adjusted for the estimated impact of collateral. Certain leases of the Registrants contain escalation clauses whereby the payments are adjusted for consumer price or labor indices. DTE Energy has leases with non-index based escalation clauses for fixed dollar or percentage increases. DTE Electric has leases with non-index based escalation clauses for fixed dollar increases. DTE Energy also has leases with variable payments based upon usage of, or revenues associated with, the leased assets. DTE Electric also has leases with variable payments based upon the usage of the leased assets. Certain leases of easements and coal railcars contain provisions whereby the Registrants have the option to terminate the lease agreement by giving notice of such termination during the time frames specified in the respective lease. The Registrants have considered such provisions in the determination of the lease term when it is reasonably certain that the lease would be terminated. The Registrants have certain leases which contain purchase options. Based upon the nature of the leased property and terms of the purchase options, the Registrants have determined it is not reasonably certain that such purchase options will be utilized. Thus, the impact of the purchase options has not been included in the determination of right-of-use assets and lease liabilities for the subject leases. The Registrants have certain leases which contain renewal options. Where the renewal options were deemed reasonably certain to occur, the impacts of such options were included in the determination of the right of use assets and lease liabilities. The Registrants have agreements with lease and non-lease components, which are generally accounted for separately. Consideration in a lease is allocated between lease and non-lease components based upon the estimated relative standalone prices. The Registrants have certain coal railcar leases for which non-lease and lease components are accounted for as a single lease component, as permitted under Topic 842. The components of lease cost for the year ended December 31, 2019 were as follows: DTE Energy DTE Electric (In millions) Operating lease cost $ 41 $ 17 Finance lease cost: Amortization of right-of-use assets 4 4 Interest of lease liabilities — — Total finance lease cost 4 4 Variable lease cost 10 — Short-term lease cost 10 3 $ 65 $ 24 The Registrants have elected not to apply the recognition requirements of Topic 842 to leases with a term of 12 months or less. DTE Energy and DTE Electric record operating, variable, and short-term lease costs as Operating Expenses on the Consolidated Statements of Operations, except for certain amounts that may be capitalized to other assets. Other information related to leases for the year ended December 31, 2019 were as follows: DTE Energy DTE Electric (In millions) Supplemental Cash Flows Information Cash paid for amounts included in the measurement of these liabilities: Operating cash flows for finance leases $ 5 $ 5 Operating cash flows for operating leases $ 40 $ 16 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 68 $ 27 Finance leases $ 8 $ — Weighted Average Remaining Lease Term Operating leases 9.7 years 10.6 years Finance leases 9.1 years 2.0 years Weighted Average Discount Rate Operating leases 3.5% 3.3% Finance leases 3.1% 3.1% The Registrants' future minimum lease payments under leases for remaining periods as of December 31, 2019 were as follows: DTE Energy DTE Electric Operating Leases Finance Leases Operating Leases Finance Leases (In millions) 2020 $ 38 $ 5 $ 14 $ 3 2021 30 5 13 4 2022 26 1 12 — 2023 20 1 10 — 2024 12 1 8 — 2025 and thereafter 67 4 38 — Total future minimum lease payments 193 17 95 7 Imputed interest (33 ) (2 ) (16 ) — $ 160 $ 15 $ 79 $ 7 Finance leases reported on the Consolidated Statement of Financial Position were as follows: DTE Energy DTE Electric December 31, 2019 (In millions) Right-of-use assets, within Property, plant, and equipment, net $ 15 $ 7 Current lease liabilities, within Current Liabilities — Other $ 4 $ 3 Topic 840 — The following disclosures are presented under Topic 840 for the year ended December 31, 2018. The Registrants lease various assets under operating leases, including coal railcars, office buildings, a warehouse, computers, vehicles, and other equipment. The lease arrangements expire at various dates through 2051 and 2046 for DTE Energy and DTE Electric, respectively. The Registrants' future minimum lease payments under non-cancelable operating leases at December 31, 2018 were as follows: DTE Energy DTE Electric (In millions) 2019 $ 42 $ 17 2020 30 12 2021 18 10 2022 11 7 2023 8 5 2024 and thereafter 45 29 $ 154 $ 80 The Registrants are the lessee under certain capital leases related to software and information technology related equipment. Property under capital leases for the Registrants as of December 31, 2018 were as follows: DTE Energy DTE Electric (In millions) Gross property under capital leases $ 18 $ 18 Accumulated amortization of property under capital leases $ 7 $ 7 Lessor Topic 842 — DTE Energy leases a portion of its pipeline system to the Vector Pipeline through a finance lease contract that has been renewed through 2025, with additional renewal options reasonably certain to be exercised through 2040. DTE Energy owns a 40% interest in the Vector Pipeline. In addition, DTE Energy has an energy services agreement that expires in 2026, of which a portion is accounted for as a finance lease. DTE Energy also leases various assets under operating leases for a pipeline, energy facilities and related equipment. Such leases are comprised of both fixed payments and variable payments which are contingent on volumes, with terms ranging from 3 to 24 years. Generally, the operating leases do not have renewal provisions or options to purchase the assets at the end of the lease. The operating leases generally do not have termination for convenience provisions. Termination may be allowed under specific circumstances stated in the lease contract, such as under an event of default. Certain of the finance and operating leases have lease terms that extend to the end of the estimated economic life of the leased assets, thereby resulting in no residual value. Any remaining residual values under the finance and operating leases are expected to be recovered through rates, renewals or new lease contracts. Residual values have been determined using the estimated economic life of the leased assets. The finance and operating leases do not contain residual value guarantees. Certain of the operating leases have both lease and non-lease components. The lease and non-lease components are allocated based upon estimated relative standalone selling prices. A lease is deemed to exist when the Registrants have provided other parties with the right to control the use of identified property, plant or equipment, as conveyed through a contract, for a certain period of time and consideration received. The right to control is deemed to occur when the Registrants have provided other parties with the right to obtain substantially all of the economic benefits of the identified assets and the right to direct the use of such assets. DTE Energy’s lease income associated with operating leases was as follows for the year ended December 31, 2019 : DTE Energy (In millions) Fixed payments (a) $ 65 Variable payments (a) 128 $ 193 _______________________________________ (a) Includes $130 million of lease payments reported in Operating Revenues and $63 million of lease payments reported in Other income on DTE Energy's Consolidated Statements of Operations. DTE Energy’s minimum future rental revenues under operating leases for remaining periods as of December 31, 2019 were as follows: DTE Energy (In millions) 2020 $ 64 2021 62 2022 22 2023 22 2024 22 2025 and thereafter 194 $ 386 Depreciation expense associated with DTE Energy's property under operating leases was $26 million for the year ended December 31, 2019 . Property under operating leases for DTE Energy as of December 31, 2019 were as follows: DTE Energy (In millions) Gross property under operating leases $ 445 Accumulated amortization of property under operating leases $ 173 The components of DTE Energy’s net investment in finance leases for remaining periods as of December 31, 2019 were as follows: DTE Energy (In millions) 2020 $ 9 2021 4 2022 4 2023 5 2024 5 2025 and thereafter 55 Total minimum future lease receipts 82 Residual value of leased pipeline 19 Less unearned income 55 Net investment in finance lease 46 Less current portion 5 $ 41 Interest income recognized under finance leases was $5 million for the year ended December 31, 2019 . Topic 840 — DTE Energy leases various assets under operating leases for energy facilities and related equipment. DTE Energy’s minimum future rental revenues under non-cancelable operating leases as of December 31, 2018 were as follows: DTE Energy (In millions) 2019 $ 66 2020 66 2021 64 2022 20 2023 20 2024 and thereafter 196 $ 432 The amounts listed above do not include contingent rentals associated with the leased assets. DTE Energy had contingent rental revenues of $107 million , $91 million , and $101 million in 2018, 2017, and 2016, respectively. DTE Energy leases a portion of its pipeline system to the Vector Pipeline through a capital lease contract that was set to expire in 2020, with renewal options extending for five years . DTE Energy owns a 40% interest in the Vector Pipeline. In addition, DTE Energy has two energy services agreements, for which a portion of are accounted for as capital leases. These agreements were set to expire in 2019 and 2026. The components of DTE Energy’s net investment in capital leases at December 31, 2018 were as follows: DTE Energy (In millions) 2019 $ 10 2020 9 2021 — 2022 — 2023 — 2024 and thereafter 1 Total minimum future lease receipts 20 Residual value of leased pipeline 40 Less unearned income 9 Net investment in capital lease 51 Less current portion 5 $ 46 Property under operating leases for DTE Energy as of December 31, 2018 were as follows: DTE Energy (In millions) Gross property under operating leases $ 447 Accumulated amortization of property under operating leases $ 148
Leases	LEASES Disclosures related to the year ended December 31, 2019 are presented as required under Topic 842. Prior period disclosures for the year ended December 31, 2018 are presented under Topic 840. The Registrants have elected to use a practical expedient provided by Topic 842 whereby comparative disclosures for prior periods are allowed to be presented under Topic 840. As a result, the disclosures presented under Topic 842 and Topic 840 will not be fully comparable in specific disclosure requirements. Lessee Topic 842 — Leases at DTE Energy are primarily comprised of various forms of equipment, computer hardware, coal railcars, production facilities, buildings, and certain easement leases with terms ranging from approximately 2 to 40 years. Leases at DTE Electric are primarily comprised of various forms of equipment, computer hardware, coal railcars, and certain easement leases with terms ranging from approximately 2 to 40 years. A lease is deemed to exist when the Registrants have the right to control the use of identified property, plant or equipment, as conveyed through a contract, for a certain period of time and consideration paid. The right to control is deemed to occur when the Registrants have the right to obtain substantially all of the economic benefits of the identified assets and the right to direct the use of such assets. Lease liabilities are determined utilizing a discount rate to determine the present values of lease payments. Topic 842 requires the use of the rate implicit in the lease when it is readily determinable. When the rate implicit in the lease is not readily determinable, the incremental borrowing rate is used. The Registrants have determined their respective incremental borrowing rates based upon the rate of interest that would have been paid on a collateralized basis over similar tenors to that of the leases. The incremental borrowing rates for DTE Electric and DTE Gas have been determined utilizing respective secured borrowing rates for first mortgage bonds with like tenors of remaining lease terms. Incremental borrowing rates for non-utility entities have been determined utilizing an implied secured borrowing rate based upon an unsecured rate for a similar tenor of remaining lease terms, which is then adjusted for the estimated impact of collateral. Certain leases of the Registrants contain escalation clauses whereby the payments are adjusted for consumer price or labor indices. DTE Energy has leases with non-index based escalation clauses for fixed dollar or percentage increases. DTE Electric has leases with non-index based escalation clauses for fixed dollar increases. DTE Energy also has leases with variable payments based upon usage of, or revenues associated with, the leased assets. DTE Electric also has leases with variable payments based upon the usage of the leased assets. Certain leases of easements and coal railcars contain provisions whereby the Registrants have the option to terminate the lease agreement by giving notice of such termination during the time frames specified in the respective lease. The Registrants have considered such provisions in the determination of the lease term when it is reasonably certain that the lease would be terminated. The Registrants have certain leases which contain purchase options. Based upon the nature of the leased property and terms of the purchase options, the Registrants have determined it is not reasonably certain that such purchase options will be utilized. Thus, the impact of the purchase options has not been included in the determination of right-of-use assets and lease liabilities for the subject leases. The Registrants have certain leases which contain renewal options. Where the renewal options were deemed reasonably certain to occur, the impacts of such options were included in the determination of the right of use assets and lease liabilities. The Registrants have agreements with lease and non-lease components, which are generally accounted for separately. Consideration in a lease is allocated between lease and non-lease components based upon the estimated relative standalone prices. The Registrants have certain coal railcar leases for which non-lease and lease components are accounted for as a single lease component, as permitted under Topic 842. The components of lease cost for the year ended December 31, 2019 were as follows: DTE Energy DTE Electric (In millions) Operating lease cost $ 41 $ 17 Finance lease cost: Amortization of right-of-use assets 4 4 Interest of lease liabilities — — Total finance lease cost 4 4 Variable lease cost 10 — Short-term lease cost 10 3 $ 65 $ 24 The Registrants have elected not to apply the recognition requirements of Topic 842 to leases with a term of 12 months or less. DTE Energy and DTE Electric record operating, variable, and short-term lease costs as Operating Expenses on the Consolidated Statements of Operations, except for certain amounts that may be capitalized to other assets. Other information related to leases for the year ended December 31, 2019 were as follows: DTE Energy DTE Electric (In millions) Supplemental Cash Flows Information Cash paid for amounts included in the measurement of these liabilities: Operating cash flows for finance leases $ 5 $ 5 Operating cash flows for operating leases $ 40 $ 16 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 68 $ 27 Finance leases $ 8 $ — Weighted Average Remaining Lease Term Operating leases 9.7 years 10.6 years Finance leases 9.1 years 2.0 years Weighted Average Discount Rate Operating leases 3.5% 3.3% Finance leases 3.1% 3.1% The Registrants' future minimum lease payments under leases for remaining periods as of December 31, 2019 were as follows: DTE Energy DTE Electric Operating Leases Finance Leases Operating Leases Finance Leases (In millions) 2020 $ 38 $ 5 $ 14 $ 3 2021 30 5 13 4 2022 26 1 12 — 2023 20 1 10 — 2024 12 1 8 — 2025 and thereafter 67 4 38 — Total future minimum lease payments 193 17 95 7 Imputed interest (33 ) (2 ) (16 ) — $ 160 $ 15 $ 79 $ 7 Finance leases reported on the Consolidated Statement of Financial Position were as follows: DTE Energy DTE Electric December 31, 2019 (In millions) Right-of-use assets, within Property, plant, and equipment, net $ 15 $ 7 Current lease liabilities, within Current Liabilities — Other $ 4 $ 3 Topic 840 — The following disclosures are presented under Topic 840 for the year ended December 31, 2018. The Registrants lease various assets under operating leases, including coal railcars, office buildings, a warehouse, computers, vehicles, and other equipment. The lease arrangements expire at various dates through 2051 and 2046 for DTE Energy and DTE Electric, respectively. The Registrants' future minimum lease payments under non-cancelable operating leases at December 31, 2018 were as follows: DTE Energy DTE Electric (In millions) 2019 $ 42 $ 17 2020 30 12 2021 18 10 2022 11 7 2023 8 5 2024 and thereafter 45 29 $ 154 $ 80 The Registrants are the lessee under certain capital leases related to software and information technology related equipment. Property under capital leases for the Registrants as of December 31, 2018 were as follows: DTE Energy DTE Electric (In millions) Gross property under capital leases $ 18 $ 18 Accumulated amortization of property under capital leases $ 7 $ 7 Lessor Topic 842 — DTE Energy leases a portion of its pipeline system to the Vector Pipeline through a finance lease contract that has been renewed through 2025, with additional renewal options reasonably certain to be exercised through 2040. DTE Energy owns a 40% interest in the Vector Pipeline. In addition, DTE Energy has an energy services agreement that expires in 2026, of which a portion is accounted for as a finance lease. DTE Energy also leases various assets under operating leases for a pipeline, energy facilities and related equipment. Such leases are comprised of both fixed payments and variable payments which are contingent on volumes, with terms ranging from 3 to 24 years. Generally, the operating leases do not have renewal provisions or options to purchase the assets at the end of the lease. The operating leases generally do not have termination for convenience provisions. Termination may be allowed under specific circumstances stated in the lease contract, such as under an event of default. Certain of the finance and operating leases have lease terms that extend to the end of the estimated economic life of the leased assets, thereby resulting in no residual value. Any remaining residual values under the finance and operating leases are expected to be recovered through rates, renewals or new lease contracts. Residual values have been determined using the estimated economic life of the leased assets. The finance and operating leases do not contain residual value guarantees. Certain of the operating leases have both lease and non-lease components. The lease and non-lease components are allocated based upon estimated relative standalone selling prices. A lease is deemed to exist when the Registrants have provided other parties with the right to control the use of identified property, plant or equipment, as conveyed through a contract, for a certain period of time and consideration received. The right to control is deemed to occur when the Registrants have provided other parties with the right to obtain substantially all of the economic benefits of the identified assets and the right to direct the use of such assets. DTE Energy’s lease income associated with operating leases was as follows for the year ended December 31, 2019 : DTE Energy (In millions) Fixed payments (a) $ 65 Variable payments (a) 128 $ 193 _______________________________________ (a) Includes $130 million of lease payments reported in Operating Revenues and $63 million of lease payments reported in Other income on DTE Energy's Consolidated Statements of Operations. DTE Energy’s minimum future rental revenues under operating leases for remaining periods as of December 31, 2019 were as follows: DTE Energy (In millions) 2020 $ 64 2021 62 2022 22 2023 22 2024 22 2025 and thereafter 194 $ 386 Depreciation expense associated with DTE Energy's property under operating leases was $26 million for the year ended December 31, 2019 . Property under operating leases for DTE Energy as of December 31, 2019 were as follows: DTE Energy (In millions) Gross property under operating leases $ 445 Accumulated amortization of property under operating leases $ 173 The components of DTE Energy’s net investment in finance leases for remaining periods as of December 31, 2019 were as follows: DTE Energy (In millions) 2020 $ 9 2021 4 2022 4 2023 5 2024 5 2025 and thereafter 55 Total minimum future lease receipts 82 Residual value of leased pipeline 19 Less unearned income 55 Net investment in finance lease 46 Less current portion 5 $ 41 Interest income recognized under finance leases was $5 million for the year ended December 31, 2019 . Topic 840 — DTE Energy leases various assets under operating leases for energy facilities and related equipment. DTE Energy’s minimum future rental revenues under non-cancelable operating leases as of December 31, 2018 were as follows: DTE Energy (In millions) 2019 $ 66 2020 66 2021 64 2022 20 2023 20 2024 and thereafter 196 $ 432 The amounts listed above do not include contingent rentals associated with the leased assets. DTE Energy had contingent rental revenues of $107 million , $91 million , and $101 million in 2018, 2017, and 2016, respectively. DTE Energy leases a portion of its pipeline system to the Vector Pipeline through a capital lease contract that was set to expire in 2020, with renewal options extending for five years . DTE Energy owns a 40% interest in the Vector Pipeline. In addition, DTE Energy has two energy services agreements, for which a portion of are accounted for as capital leases. These agreements were set to expire in 2019 and 2026. The components of DTE Energy’s net investment in capital leases at December 31, 2018 were as follows: DTE Energy (In millions) 2019 $ 10 2020 9 2021 — 2022 — 2023 — 2024 and thereafter 1 Total minimum future lease receipts 20 Residual value of leased pipeline 40 Less unearned income 9 Net investment in capital lease 51 Less current portion 5 $ 46 Property under operating leases for DTE Energy as of December 31, 2018 were as follows: DTE Energy (In millions) Gross property under operating leases $ 447 Accumulated amortization of property under operating leases $ 148
Leases	LEASES Disclosures related to the year ended December 31, 2019 are presented as required under Topic 842. Prior period disclosures for the year ended December 31, 2018 are presented under Topic 840. The Registrants have elected to use a practical expedient provided by Topic 842 whereby comparative disclosures for prior periods are allowed to be presented under Topic 840. As a result, the disclosures presented under Topic 842 and Topic 840 will not be fully comparable in specific disclosure requirements. Lessee Topic 842 — Leases at DTE Energy are primarily comprised of various forms of equipment, computer hardware, coal railcars, production facilities, buildings, and certain easement leases with terms ranging from approximately 2 to 40 years. Leases at DTE Electric are primarily comprised of various forms of equipment, computer hardware, coal railcars, and certain easement leases with terms ranging from approximately 2 to 40 years. A lease is deemed to exist when the Registrants have the right to control the use of identified property, plant or equipment, as conveyed through a contract, for a certain period of time and consideration paid. The right to control is deemed to occur when the Registrants have the right to obtain substantially all of the economic benefits of the identified assets and the right to direct the use of such assets. Lease liabilities are determined utilizing a discount rate to determine the present values of lease payments. Topic 842 requires the use of the rate implicit in the lease when it is readily determinable. When the rate implicit in the lease is not readily determinable, the incremental borrowing rate is used. The Registrants have determined their respective incremental borrowing rates based upon the rate of interest that would have been paid on a collateralized basis over similar tenors to that of the leases. The incremental borrowing rates for DTE Electric and DTE Gas have been determined utilizing respective secured borrowing rates for first mortgage bonds with like tenors of remaining lease terms. Incremental borrowing rates for non-utility entities have been determined utilizing an implied secured borrowing rate based upon an unsecured rate for a similar tenor of remaining lease terms, which is then adjusted for the estimated impact of collateral. Certain leases of the Registrants contain escalation clauses whereby the payments are adjusted for consumer price or labor indices. DTE Energy has leases with non-index based escalation clauses for fixed dollar or percentage increases. DTE Electric has leases with non-index based escalation clauses for fixed dollar increases. DTE Energy also has leases with variable payments based upon usage of, or revenues associated with, the leased assets. DTE Electric also has leases with variable payments based upon the usage of the leased assets. Certain leases of easements and coal railcars contain provisions whereby the Registrants have the option to terminate the lease agreement by giving notice of such termination during the time frames specified in the respective lease. The Registrants have considered such provisions in the determination of the lease term when it is reasonably certain that the lease would be terminated. The Registrants have certain leases which contain purchase options. Based upon the nature of the leased property and terms of the purchase options, the Registrants have determined it is not reasonably certain that such purchase options will be utilized. Thus, the impact of the purchase options has not been included in the determination of right-of-use assets and lease liabilities for the subject leases. The Registrants have certain leases which contain renewal options. Where the renewal options were deemed reasonably certain to occur, the impacts of such options were included in the determination of the right of use assets and lease liabilities. The Registrants have agreements with lease and non-lease components, which are generally accounted for separately. Consideration in a lease is allocated between lease and non-lease components based upon the estimated relative standalone prices. The Registrants have certain coal railcar leases for which non-lease and lease components are accounted for as a single lease component, as permitted under Topic 842. The components of lease cost for the year ended December 31, 2019 were as follows: DTE Energy DTE Electric (In millions) Operating lease cost $ 41 $ 17 Finance lease cost: Amortization of right-of-use assets 4 4 Interest of lease liabilities — — Total finance lease cost 4 4 Variable lease cost 10 — Short-term lease cost 10 3 $ 65 $ 24 The Registrants have elected not to apply the recognition requirements of Topic 842 to leases with a term of 12 months or less. DTE Energy and DTE Electric record operating, variable, and short-term lease costs as Operating Expenses on the Consolidated Statements of Operations, except for certain amounts that may be capitalized to other assets. Other information related to leases for the year ended December 31, 2019 were as follows: DTE Energy DTE Electric (In millions) Supplemental Cash Flows Information Cash paid for amounts included in the measurement of these liabilities: Operating cash flows for finance leases $ 5 $ 5 Operating cash flows for operating leases $ 40 $ 16 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 68 $ 27 Finance leases $ 8 $ — Weighted Average Remaining Lease Term Operating leases 9.7 years 10.6 years Finance leases 9.1 years 2.0 years Weighted Average Discount Rate Operating leases 3.5% 3.3% Finance leases 3.1% 3.1% The Registrants' future minimum lease payments under leases for remaining periods as of December 31, 2019 were as follows: DTE Energy DTE Electric Operating Leases Finance Leases Operating Leases Finance Leases (In millions) 2020 $ 38 $ 5 $ 14 $ 3 2021 30 5 13 4 2022 26 1 12 — 2023 20 1 10 — 2024 12 1 8 — 2025 and thereafter 67 4 38 — Total future minimum lease payments 193 17 95 7 Imputed interest (33 ) (2 ) (16 ) — $ 160 $ 15 $ 79 $ 7 Finance leases reported on the Consolidated Statement of Financial Position were as follows: DTE Energy DTE Electric December 31, 2019 (In millions) Right-of-use assets, within Property, plant, and equipment, net $ 15 $ 7 Current lease liabilities, within Current Liabilities — Other $ 4 $ 3 Topic 840 — The following disclosures are presented under Topic 840 for the year ended December 31, 2018. The Registrants lease various assets under operating leases, including coal railcars, office buildings, a warehouse, computers, vehicles, and other equipment. The lease arrangements expire at various dates through 2051 and 2046 for DTE Energy and DTE Electric, respectively. The Registrants' future minimum lease payments under non-cancelable operating leases at December 31, 2018 were as follows: DTE Energy DTE Electric (In millions) 2019 $ 42 $ 17 2020 30 12 2021 18 10 2022 11 7 2023 8 5 2024 and thereafter 45 29 $ 154 $ 80 The Registrants are the lessee under certain capital leases related to software and information technology related equipment. Property under capital leases for the Registrants as of December 31, 2018 were as follows: DTE Energy DTE Electric (In millions) Gross property under capital leases $ 18 $ 18 Accumulated amortization of property under capital leases $ 7 $ 7 Lessor Topic 842 — DTE Energy leases a portion of its pipeline system to the Vector Pipeline through a finance lease contract that has been renewed through 2025, with additional renewal options reasonably certain to be exercised through 2040. DTE Energy owns a 40% interest in the Vector Pipeline. In addition, DTE Energy has an energy services agreement that expires in 2026, of which a portion is accounted for as a finance lease. DTE Energy also leases various assets under operating leases for a pipeline, energy facilities and related equipment. Such leases are comprised of both fixed payments and variable payments which are contingent on volumes, with terms ranging from 3 to 24 years. Generally, the operating leases do not have renewal provisions or options to purchase the assets at the end of the lease. The operating leases generally do not have termination for convenience provisions. Termination may be allowed under specific circumstances stated in the lease contract, such as under an event of default. Certain of the finance and operating leases have lease terms that extend to the end of the estimated economic life of the leased assets, thereby resulting in no residual value. Any remaining residual values under the finance and operating leases are expected to be recovered through rates, renewals or new lease contracts. Residual values have been determined using the estimated economic life of the leased assets. The finance and operating leases do not contain residual value guarantees. Certain of the operating leases have both lease and non-lease components. The lease and non-lease components are allocated based upon estimated relative standalone selling prices. A lease is deemed to exist when the Registrants have provided other parties with the right to control the use of identified property, plant or equipment, as conveyed through a contract, for a certain period of time and consideration received. The right to control is deemed to occur when the Registrants have provided other parties with the right to obtain substantially all of the economic benefits of the identified assets and the right to direct the use of such assets. DTE Energy’s lease income associated with operating leases was as follows for the year ended December 31, 2019 : DTE Energy (In millions) Fixed payments (a) $ 65 Variable payments (a) 128 $ 193 _______________________________________ (a) Includes $130 million of lease payments reported in Operating Revenues and $63 million of lease payments reported in Other income on DTE Energy's Consolidated Statements of Operations. DTE Energy’s minimum future rental revenues under operating leases for remaining periods as of December 31, 2019 were as follows: DTE Energy (In millions) 2020 $ 64 2021 62 2022 22 2023 22 2024 22 2025 and thereafter 194 $ 386 Depreciation expense associated with DTE Energy's property under operating leases was $26 million for the year ended December 31, 2019 . Property under operating leases for DTE Energy as of December 31, 2019 were as follows: DTE Energy (In millions) Gross property under operating leases $ 445 Accumulated amortization of property under operating leases $ 173 The components of DTE Energy’s net investment in finance leases for remaining periods as of December 31, 2019 were as follows: DTE Energy (In millions) 2020 $ 9 2021 4 2022 4 2023 5 2024 5 2025 and thereafter 55 Total minimum future lease receipts 82 Residual value of leased pipeline 19 Less unearned income 55 Net investment in finance lease 46 Less current portion 5 $ 41 Interest income recognized under finance leases was $5 million for the year ended December 31, 2019 . Topic 840 — DTE Energy leases various assets under operating leases for energy facilities and related equipment. DTE Energy’s minimum future rental revenues under non-cancelable operating leases as of December 31, 2018 were as follows: DTE Energy (In millions) 2019 $ 66 2020 66 2021 64 2022 20 2023 20 2024 and thereafter 196 $ 432 The amounts listed above do not include contingent rentals associated with the leased assets. DTE Energy had contingent rental revenues of $107 million , $91 million , and $101 million in 2018, 2017, and 2016, respectively. DTE Energy leases a portion of its pipeline system to the Vector Pipeline through a capital lease contract that was set to expire in 2020, with renewal options extending for five years . DTE Energy owns a 40% interest in the Vector Pipeline. In addition, DTE Energy has two energy services agreements, for which a portion of are accounted for as capital leases. These agreements were set to expire in 2019 and 2026. The components of DTE Energy’s net investment in capital leases at December 31, 2018 were as follows: DTE Energy (In millions) 2019 $ 10 2020 9 2021 — 2022 — 2023 — 2024 and thereafter 1 Total minimum future lease receipts 20 Residual value of leased pipeline 40 Less unearned income 9 Net investment in capital lease 51 Less current portion 5 $ 46 Property under operating leases for DTE Energy as of December 31, 2018 were as follows: DTE Energy (In millions) Gross property under operating leases $ 447 Accumulated amortization of property under operating leases $ 148
Leases	LEASES Disclosures related to the year ended December 31, 2019 are presented as required under Topic 842. Prior period disclosures for the year ended December 31, 2018 are presented under Topic 840. The Registrants have elected to use a practical expedient provided by Topic 842 whereby comparative disclosures for prior periods are allowed to be presented under Topic 840. As a result, the disclosures presented under Topic 842 and Topic 840 will not be fully comparable in specific disclosure requirements. Lessee Topic 842 — Leases at DTE Energy are primarily comprised of various forms of equipment, computer hardware, coal railcars, production facilities, buildings, and certain easement leases with terms ranging from approximately 2 to 40 years. Leases at DTE Electric are primarily comprised of various forms of equipment, computer hardware, coal railcars, and certain easement leases with terms ranging from approximately 2 to 40 years. A lease is deemed to exist when the Registrants have the right to control the use of identified property, plant or equipment, as conveyed through a contract, for a certain period of time and consideration paid. The right to control is deemed to occur when the Registrants have the right to obtain substantially all of the economic benefits of the identified assets and the right to direct the use of such assets. Lease liabilities are determined utilizing a discount rate to determine the present values of lease payments. Topic 842 requires the use of the rate implicit in the lease when it is readily determinable. When the rate implicit in the lease is not readily determinable, the incremental borrowing rate is used. The Registrants have determined their respective incremental borrowing rates based upon the rate of interest that would have been paid on a collateralized basis over similar tenors to that of the leases. The incremental borrowing rates for DTE Electric and DTE Gas have been determined utilizing respective secured borrowing rates for first mortgage bonds with like tenors of remaining lease terms. Incremental borrowing rates for non-utility entities have been determined utilizing an implied secured borrowing rate based upon an unsecured rate for a similar tenor of remaining lease terms, which is then adjusted for the estimated impact of collateral. Certain leases of the Registrants contain escalation clauses whereby the payments are adjusted for consumer price or labor indices. DTE Energy has leases with non-index based escalation clauses for fixed dollar or percentage increases. DTE Electric has leases with non-index based escalation clauses for fixed dollar increases. DTE Energy also has leases with variable payments based upon usage of, or revenues associated with, the leased assets. DTE Electric also has leases with variable payments based upon the usage of the leased assets. Certain leases of easements and coal railcars contain provisions whereby the Registrants have the option to terminate the lease agreement by giving notice of such termination during the time frames specified in the respective lease. The Registrants have considered such provisions in the determination of the lease term when it is reasonably certain that the lease would be terminated. The Registrants have certain leases which contain purchase options. Based upon the nature of the leased property and terms of the purchase options, the Registrants have determined it is not reasonably certain that such purchase options will be utilized. Thus, the impact of the purchase options has not been included in the determination of right-of-use assets and lease liabilities for the subject leases. The Registrants have certain leases which contain renewal options. Where the renewal options were deemed reasonably certain to occur, the impacts of such options were included in the determination of the right of use assets and lease liabilities. The Registrants have agreements with lease and non-lease components, which are generally accounted for separately. Consideration in a lease is allocated between lease and non-lease components based upon the estimated relative standalone prices. The Registrants have certain coal railcar leases for which non-lease and lease components are accounted for as a single lease component, as permitted under Topic 842. The components of lease cost for the year ended December 31, 2019 were as follows: DTE Energy DTE Electric (In millions) Operating lease cost $ 41 $ 17 Finance lease cost: Amortization of right-of-use assets 4 4 Interest of lease liabilities — — Total finance lease cost 4 4 Variable lease cost 10 — Short-term lease cost 10 3 $ 65 $ 24 The Registrants have elected not to apply the recognition requirements of Topic 842 to leases with a term of 12 months or less. DTE Energy and DTE Electric record operating, variable, and short-term lease costs as Operating Expenses on the Consolidated Statements of Operations, except for certain amounts that may be capitalized to other assets. Other information related to leases for the year ended December 31, 2019 were as follows: DTE Energy DTE Electric (In millions) Supplemental Cash Flows Information Cash paid for amounts included in the measurement of these liabilities: Operating cash flows for finance leases $ 5 $ 5 Operating cash flows for operating leases $ 40 $ 16 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 68 $ 27 Finance leases $ 8 $ — Weighted Average Remaining Lease Term Operating leases 9.7 years 10.6 years Finance leases 9.1 years 2.0 years Weighted Average Discount Rate Operating leases 3.5% 3.3% Finance leases 3.1% 3.1% The Registrants' future minimum lease payments under leases for remaining periods as of December 31, 2019 were as follows: DTE Energy DTE Electric Operating Leases Finance Leases Operating Leases Finance Leases (In millions) 2020 $ 38 $ 5 $ 14 $ 3 2021 30 5 13 4 2022 26 1 12 — 2023 20 1 10 — 2024 12 1 8 — 2025 and thereafter 67 4 38 — Total future minimum lease payments 193 17 95 7 Imputed interest (33 ) (2 ) (16 ) — $ 160 $ 15 $ 79 $ 7 Finance leases reported on the Consolidated Statement of Financial Position were as follows: DTE Energy DTE Electric December 31, 2019 (In millions) Right-of-use assets, within Property, plant, and equipment, net $ 15 $ 7 Current lease liabilities, within Current Liabilities — Other $ 4 $ 3 Topic 840 — The following disclosures are presented under Topic 840 for the year ended December 31, 2018. The Registrants lease various assets under operating leases, including coal railcars, office buildings, a warehouse, computers, vehicles, and other equipment. The lease arrangements expire at various dates through 2051 and 2046 for DTE Energy and DTE Electric, respectively. The Registrants' future minimum lease payments under non-cancelable operating leases at December 31, 2018 were as follows: DTE Energy DTE Electric (In millions) 2019 $ 42 $ 17 2020 30 12 2021 18 10 2022 11 7 2023 8 5 2024 and thereafter 45 29 $ 154 $ 80 The Registrants are the lessee under certain capital leases related to software and information technology related equipment. Property under capital leases for the Registrants as of December 31, 2018 were as follows: DTE Energy DTE Electric (In millions) Gross property under capital leases $ 18 $ 18 Accumulated amortization of property under capital leases $ 7 $ 7 Lessor Topic 842 — DTE Energy leases a portion of its pipeline system to the Vector Pipeline through a finance lease contract that has been renewed through 2025, with additional renewal options reasonably certain to be exercised through 2040. DTE Energy owns a 40% interest in the Vector Pipeline. In addition, DTE Energy has an energy services agreement that expires in 2026, of which a portion is accounted for as a finance lease. DTE Energy also leases various assets under operating leases for a pipeline, energy facilities and related equipment. Such leases are comprised of both fixed payments and variable payments which are contingent on volumes, with terms ranging from 3 to 24 years. Generally, the operating leases do not have renewal provisions or options to purchase the assets at the end of the lease. The operating leases generally do not have termination for convenience provisions. Termination may be allowed under specific circumstances stated in the lease contract, such as under an event of default. Certain of the finance and operating leases have lease terms that extend to the end of the estimated economic life of the leased assets, thereby resulting in no residual value. Any remaining residual values under the finance and operating leases are expected to be recovered through rates, renewals or new lease contracts. Residual values have been determined using the estimated economic life of the leased assets. The finance and operating leases do not contain residual value guarantees. Certain of the operating leases have both lease and non-lease components. The lease and non-lease components are allocated based upon estimated relative standalone selling prices. A lease is deemed to exist when the Registrants have provided other parties with the right to control the use of identified property, plant or equipment, as conveyed through a contract, for a certain period of time and consideration received. The right to control is deemed to occur when the Registrants have provided other parties with the right to obtain substantially all of the economic benefits of the identified assets and the right to direct the use of such assets. DTE Energy’s lease income associated with operating leases was as follows for the year ended December 31, 2019 : DTE Energy (In millions) Fixed payments (a) $ 65 Variable payments (a) 128 $ 193 _______________________________________ (a) Includes $130 million of lease payments reported in Operating Revenues and $63 million of lease payments reported in Other income on DTE Energy's Consolidated Statements of Operations. DTE Energy’s minimum future rental revenues under operating leases for remaining periods as of December 31, 2019 were as follows: DTE Energy (In millions) 2020 $ 64 2021 62 2022 22 2023 22 2024 22 2025 and thereafter 194 $ 386 Depreciation expense associated with DTE Energy's property under operating leases was $26 million for the year ended December 31, 2019 . Property under operating leases for DTE Energy as of December 31, 2019 were as follows: DTE Energy (In millions) Gross property under operating leases $ 445 Accumulated amortization of property under operating leases $ 173 The components of DTE Energy’s net investment in finance leases for remaining periods as of December 31, 2019 were as follows: DTE Energy (In millions) 2020 $ 9 2021 4 2022 4 2023 5 2024 5 2025 and thereafter 55 Total minimum future lease receipts 82 Residual value of leased pipeline 19 Less unearned income 55 Net investment in finance lease 46 Less current portion 5 $ 41 Interest income recognized under finance leases was $5 million for the year ended December 31, 2019 . Topic 840 — DTE Energy leases various assets under operating leases for energy facilities and related equipment. DTE Energy’s minimum future rental revenues under non-cancelable operating leases as of December 31, 2018 were as follows: DTE Energy (In millions) 2019 $ 66 2020 66 2021 64 2022 20 2023 20 2024 and thereafter 196 $ 432 The amounts listed above do not include contingent rentals associated with the leased assets. DTE Energy had contingent rental revenues of $107 million , $91 million , and $101 million in 2018, 2017, and 2016, respectively. DTE Energy leases a portion of its pipeline system to the Vector Pipeline through a capital lease contract that was set to expire in 2020, with renewal options extending for five years . DTE Energy owns a 40% interest in the Vector Pipeline. In addition, DTE Energy has two energy services agreements, for which a portion of are accounted for as capital leases. These agreements were set to expire in 2019 and 2026. The components of DTE Energy’s net investment in capital leases at December 31, 2018 were as follows: DTE Energy (In millions) 2019 $ 10 2020 9 2021 — 2022 — 2023 — 2024 and thereafter 1 Total minimum future lease receipts 20 Residual value of leased pipeline 40 Less unearned income 9 Net investment in capital lease 51 Less current portion 5 $ 46 Property under operating leases for DTE Energy as of December 31, 2018 were as follows: DTE Energy (In millions) Gross property under operating leases $ 447 Accumulated amortization of property under operating leases $ 148

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES Environmental DTE Electric Air — DTE Electric is subject to the EPA ozone and fine particulate transport and acid rain regulations that limit power plant emissions of SO 2 and NO X . The EPA and the State of Michigan have also issued emission reduction regulations relating to ozone, fine particulate, regional haze, mercury, and other air pollution. These rules have led to controls on fossil-fueled power plants to reduce SO 2 , NO X , mercury, and other emissions. Additional rulemakings may occur over the next few years which could require additional controls for SO 2 , NO X , and other hazardous air pollutants. The EPA proposed revised air quality standards for ground level ozone in November 2014 and specifically requested comments on the form and level of the ozone standards. The standards were finalized in October 2015. The State of Michigan recommended to the EPA in October 2016 which areas of the state are not attaining the new standard. On April 30, 2018, the EPA finalized the State of Michigan's recommended marginal non-attainment designation for southeast Michigan. The State is required to develop and implement a plan to address the southeast Michigan ozone non-attainment area by 2021. The Registrants cannot predict the financial impact of the State's plan to address the ozone non-attainment area at this time. In July 2009, the Registrants received a NOV/FOV from the EPA alleging, among other things, that five DTE Electric power plants violated New Source Performance standards, Prevention of Significant Deterioration requirements, and operating permit requirements under the Clean Air Act. In June 2010, the EPA issued a NOV/FOV making similar allegations related to a project and outage at Unit 2 of the Monroe Power Plant. In March 2013, DTE Energy received a supplemental NOV from the EPA relating to the July 2009 NOV/FOV. The supplemental NOV alleged additional violations relating to the New Source Review provisions under the Clean Air Act, among other things. In August 2010, the U.S. Department of Justice, at the request of the EPA, brought a civil suit in the U.S. District Court for the Eastern District of Michigan against DTE Energy and DTE Electric, related to the June 2010 NOV/FOV and the outage work performed at Unit 2 of the Monroe Power Plant. In August 2011, the U.S. District Court judge granted DTE Energy's motion for summary judgment in the civil case, dismissing the case and entering judgment in favor of DTE Energy and DTE Electric. In October 2011, the EPA filed a Notice of Appeal to the Court of Appeals for the Sixth Circuit. In March 2013, the Court of Appeals remanded the case to the U.S. District Court for review of the procedural component of the New Source Review notification requirements. In September 2013, the EPA filed a motion seeking leave to amend their complaint regarding the June 2010 NOV/FOV adding additional claims related to outage work performed at the Trenton Channel and Belle River Power Plants as well as additional claims related to work performed at the Monroe Power Plant. In March 2014, the U.S. District Court judge again granted DTE Energy's motion for summary judgment dismissing the civil case related to Monroe Unit 2. In April 2014, the U.S. District Court judge granted motions filed by the EPA and the Sierra Club to amend their New Source Review complaint adding additional claims for Monroe Units 1, 2, and 3, Belle River Units 1 and 2, and Trenton Channel Unit 9. In October 2014, the EPA and the U.S. Department of Justice filed a notice of appeal of the U.S. District Court judge's dismissal of the Monroe Unit 2 case. The amended New Source Review claims were all stayed pending resolution of the appeal by the Court of Appeals for the Sixth Circuit. On January 10, 2017, a divided panel of the Court reversed the decision of the U.S. District Court. On May 8, 2017, DTE Energy and DTE Electric filed a motion to stay the mandate pending filing of a petition for writ of certiorari with the U.S. Supreme Court. The Sixth Circuit granted the motion on May 16, 2017, staying the claims in the U.S. District Court until the U.S. Supreme Court disposes of the case. DTE Electric and DTE Energy filed a petition for writ of certiorari on July 31, 2017. On December 11, 2017, the U.S. Supreme Court denied certiorari. As a result of the Supreme Court electing not to review the matter, the case was sent back to the U.S. District Court for further proceedings and on June 14, 2018 the case was stayed pending settlement negotiations. The proceedings at the District Court remain stayed while the parties discuss potential resolution of the matter. The Registrants believe that the plants and generating units identified by the EPA and the Sierra Club have complied with all applicable federal environmental regulations. Depending upon the outcome of the litigation and further discussions with the EPA regarding the two NOVs/FOVs, DTE Electric could be required to install additional pollution control equipment at some or all of the power plants in question, implement early retirement of facilities where control equipment is not economical, engage in supplemental environmental programs, and/or pay fines. The Registrants do not expect the outcome of this matter to have a material impact on their Consolidated Financial Statements. The EPA has implemented regulatory actions under the Clean Air Act to address emissions of GHGs from the utility sector and other sectors of the economy. Among these actions, in 2015 the EPA finalized performance standards for emissions of carbon dioxide from new and existing fossil-fuel fired EGUs. The performance standards for existing EGUs, known as the EPA Clean Power Plan, were challenged by petitioners and stayed by the U.S. Supreme Court in February 2016 pending final review by the courts. On October 10, 2017, the EPA, under a new administration, proposed to rescind the Clean Power Plan, and in August 2018, the EPA proposed revised emission guidelines for GHGs from existing EGUs. On June 19, 2019, the EPA Administrator officially repealed the Clean Power Plan and finalized its replacement, named the ACE rule. The ACE Rule requires the state of Michigan to submit a plan in 2022 that includes GHG standards for existing coal-fired power plant units in Michigan. These final rules do not impact DTE Energy's revised commitment to reduce carbon emissions 32% by the early 2020s, 50% by 2030, and 80% by 2040, or its goal of net zero emissions by 2050 for DTE Electric, from the 2005 carbon emissions levels. In addition to the GHG standards for existing EGUs, in December 2018, the EPA issued proposed revisions to the carbon dioxide performance standards for new, modified, or reconstructed fossil-fuel fired EGUs. The carbon standards for new sources are not expected to have a material impact on DTE Electric, since DTE Electric has no plans to build new coal-fired generation and any potential new gas generation will be able to comply with the standards. Pending or future legislation or other regulatory actions could have a material impact on DTE Electric's operations and financial position and the rates charged to its customers. Impacts include expenditures for environmental equipment beyond what is currently planned, financing costs related to additional capital expenditures, the purchase of emission credits from market sources, higher costs of purchased power, and the retirement of facilities where control equipment is not economical. DTE Electric would seek to recover these incremental costs through increased rates charged to its utility customers, as authorized by the MPSC. To comply with air pollution requirements, DTE Electric spent approximately $2.4 billion through 2019 . DTE Electric does no t anticipate additional capital expenditures for air pollution requirements through 2026 , subject to the results of future rulemakings. Water — In response to an EPA regulation, DTE Electric was required to examine alternatives for reducing the environmental impacts of the cooling water intake structures at several of its facilities. Based on the results of completed studies and expected future studies, DTE Electric may be required to install technologies to reduce the impacts of the water intake structures. A final rule became effective in October 2014. The final rule requires studies to be completed and submitted as part of the National Pollutant Discharge Elimination System (NPDES) permit application process to determine the type of technology needed to reduce impacts to fish. DTE Electric has initiated the process of completing the required studies. Final compliance for the installation of any required technology will be determined by the state on a case by case, site specific basis. DTE Electric is currently evaluating the compliance options and working with the State of Michigan on evaluating whether any controls are needed. These evaluations/studies may require modifications to some existing intake structures. It is not possible to quantify the impact of this rulemaking at this time. Contaminated and Other Sites — Prior to the construction of major interstate natural gas pipelines, gas for heating and other uses was manufactured locally from processes involving coal, coke, or oil. The facilities, which produced gas, have been designated as MGP sites. DTE Electric conducted remedial investigations at contaminated sites, including three former MGP sites. The investigations have revealed contamination related to the by-products of gas manufacturing at each MGP site. In addition to the MGP sites, DTE Electric is also in the process of cleaning up other contaminated sites, including the area surrounding an ash landfill, electrical distribution substations, electric generating power plants, and underground and aboveground storage tank locations. The findings of these investigations indicated that the estimated cost to remediate these sites is expected to be incurred over the next several years. At December 31, 2019 and 2018 , DTE Electric had $8 million and $7 million , respectively, accrued for remediation. Any change in assumptions, such as remediation techniques, nature and extent of contamination, and regulatory requirements, could impact the estimate of remedial action costs for the sites and affect DTE Electric’s financial position and cash flows. DTE Electric believes the likelihood of a material change to the accrued amount is remote based on current knowledge of the conditions at each site. Coal Combustion Residuals and Effluent Limitations Guidelines — A final EPA rule for the disposal of coal combustion residuals, commonly known as coal ash, became effective in October 2015, and was revised in October 2016 and July 2018. The rule is based on the continued listing of coal ash as a non-hazardous waste and relies on various self-implementation design and performance standards. DTE Electric owns and operates three permitted engineered coal ash storage facilities to dispose of coal ash from coal-fired power plants and operates a number of smaller impoundments at its power plants subject to certain provisions in the CCR rule. At certain facilities, the rule currently requires the installation of monitoring wells, compliance with groundwater standards, and the closure of basins at the end of the useful life of the associated power plant. At other facilities, the rule requires ash laden waters be moved from earthen basins to steel and concrete tanks. DTE Electric has estimated the impact of the current rule to be $608 million . On December 2, 2019 a proposed revision to the CCR Rule was published in the Federal Register to address the D.C. Circuit’s 2018 decision regarding CCR impoundments that are not lined with an engineered liner system. The rule proposes that all CCR impoundments that do not meet the engineered liner requirements must close by specific dates, and it further confirms that all clay lined impoundments are viewed as unlined. The EPA is also preparing a rulemaking, expected to be proposed early in 2020, that will provide mechanisms to determine if certain alternative liner systems may be as protective as the current liners specified in the CCR rule. DTE Electric is currently evaluating options based on the range of outcomes of the current proposed rule and the anticipated proposed rule to determine any changes to DTE Electric's plans in the operation and closure of coal ash impoundments. At the State level, legislation was signed by the Governor in December 2018 and provides for further regulation of the CCR program in Michigan. Additionally, the bill provides the basis of a CCR program that EGLE will submit to the EPA for approval to fully regulate the CCR program in Michigan in lieu of a Federal permit program. In November 2015, the EPA finalized the ELG Rule for the steam electric power generating industry which requires additional controls to be installed between 2018 and 2023. Compliance schedules for individual facilities and individual waste streams are determined through issuance of new National Pollutant Discharge Elimination System (NPDES) permits by the State of Michigan. The State of Michigan has issued a NPDES permit for the Belle River Power Plant establishing a compliance deadline of December 31, 2021. No new permits that would require ELG compliance have been issued for other facilities, consequently no compliance timelines have been established. On April 12, 2017, the EPA granted a petition for reconsideration of the 2015 ELG Rule. The EPA also signed an administrative stay of the ELG Rule’s compliance deadlines for fly ash transport water, bottom ash transport water, and flue gas desulfurization (FGD) wastewater, among others. On June 6, 2017, the EPA published in the Federal Register a proposed rule (Postponement Rule) to postpone certain applicable deadlines within the 2015 ELG rule. The Postponement Rule was published on September 18, 2017. The Postponement Rule nullified the administrative stay but also extended the earliest compliance deadlines for only FGD wastewater and bottom ash transport water until November 1, 2020 in order for the EPA to propose and finalize a new ruling. On November 22, 2019, the EPA issued a proposed rule to revise the technology-based effluent limitations guidelines and standards applicable to flue gas desulfurization wastewater and bottom ash transport water. The ELG compliance requirements and final deadlines for bottom ash transport water and FGD wastewater, and total ELG related compliance costs will not be known until the EPA completes its reconsideration of the ELG Rule expected by the end of 2020. DTE Gas Contaminated and Other Sites — DTE Gas owns or previously owned, 14 former MGP sites. Investigations have revealed contamination related to the by-products of gas manufacturing at each site. Cleanup of eight of the MGP sites is complete and the sites are closed. DTE Gas has also completed partial closure of four additional sites. Cleanup activities associated with the remaining sites will continue over the next several years. The MPSC has established a cost deferral and rate recovery mechanism for investigation and remediation costs incurred at former MGP sites. In addition to the MGP sites, DTE Gas is also in the process of cleaning up other contaminated sites, including gate stations, gas pipeline releases, and underground storage tank locations. As of December 31, 2019 and 2018 , DTE Gas had $25 million accrued for remediation. Any change in assumptions, such as remediation techniques, nature and extent of contamination, and regulatory requirements, could impact the estimate of remedial action costs for the sites and affect DTE Gas' financial position and cash flows. DTE Gas anticipates the cost amortization methodology approved by the MPSC, which allows for amortization of the MGP costs over a ten -year period beginning with the year subsequent to the year the MGP costs were incurred, will prevent the associated investigation and remediation costs from having a material adverse impact on DTE Gas' results of operations. Non-utility DTE Energy's non-utility businesses are subject to a number of environmental laws and regulations dealing with the protection of the environment from various pollutants. In March 2019, the EPA issued a finding of violation to EES Coke, the Michigan coke battery facility that is a wholly-owned subsidiary of DTE Energy, alleging that the 2008 and 2014 permits issued by EGLE did not comply with the Clean Air Act. EES Coke evaluated the EPA's alleged violations and believes that the permits approved by EGLE complied with the Clean Air Act. Discussions with the EPA are ongoing. At the present time, DTE Energy does not believe this will have a material financial impact. Other In 2010, the EPA finalized a new one -hour SO 2 ambient air quality standard that requires states to submit plans and associated timelines for non-attainment areas that demonstrate attainment with the new SO 2 standard in phases. Phase 1 addresses non-attainment areas designated based on ambient monitoring data. Phase 2 addresses non-attainment areas with large sources of SO 2 and modeled concentrations exceeding the National Ambient Air Quality Standards for SO 2 . Phase 3 addresses smaller sources of SO 2 with modeled or monitored exceedances of the new SO 2 standard. Michigan's Phase 1 non-attainment area includes DTE Energy facilities in southwest Detroit and areas of Wayne County. Modeling runs by EGLE suggest that emission reductions may be required by significant sources of SO 2 emissions in these areas, including DTE Electric power plants and DTE Energy's Michigan coke battery facility. As part of the state implementation plan (SIP) process, DTE Energy has worked with EGLE to develop air permits reflecting significant SO2 emission reductions that, in combination with other non-DTE Energy sources' emission reduction strategies, will help the state attain the standard and sustain its attainment. Since several non-DTE Energy sources are also part of the proposed compliance plan, DTE Energy is unable to determine the full impact of the final required emissions reductions on DTE's facilities at this time. Michigan's Phase 2 non-attainment area includes DTE Electric facilities in St. Clair County. State implementation plan submittal and EPA approval describing the control strategy and timeline for demonstrating compliance with the new SO 2 standard is the next step in the process and is expected to be completed by first quarter 2020. DTE Energy is currently working with EGLE to develop the required SIP. DTE Energy is unable to determine the full impact of the SIP strategy. Synthetic Fuel Guarantees DTE Energy discontinued the operations of its synthetic fuel production facilities throughout the United States as of December 31, 2007. DTE Energy provided certain guarantees and indemnities in conjunction with the sales of interests in its synfuel facilities. The guarantees cover potential commercial, environmental, oil price, and tax-related obligations that will survive until 90 days after expiration of all applicable statutes of limitations. DTE Energy estimates that its maximum potential liability under these guarantees at December 31, 2019 was approximately $400 million . Payment under these guarantees are considered remote. REF Guarantees DTE Energy has provided certain guarantees and indemnities in conjunction with the sales of interests in or lease of its REF facilities. The guarantees cover potential commercial, environmental, and tax-related obligations that will survive until 90 days after expiration of all applicable statutes of limitations. DTE Energy estimates that its maximum potential liability under these guarantees at December 31, 2019 was $549 million . Payments under these guarantees are considered remote. NEXUS Guarantees NEXUS is party to certain 15 -year capacity agreements for the transportation of natural gas with DTE Gas and Texas Eastern Transmission, LP, an unrelated third party. In conjunction with these agreements, DTE Energy provided certain guarantees on behalf of NEXUS to DTE Gas and Texas Eastern Transmission, LP, with maximum potential payments totaling $226 million and $360 million at December 31, 2019 , respectively; each representing 50% of all payment obligations due and payable by NEXUS. Each guarantee terminates at the earlier of (i) such time as all of the guaranteed obligations have been fully performed, or (ii) two months following the end of the primary term of the capacity agreements. In October 2018, NEXUS Pipeline was placed in service. The amount of each guarantee decreases annually as payments are made by NEXUS to each of the aforementioned counterparties. NEXUS is also party to certain 15 -year capacity agreements for the transportation of natural gas with Vector, an equity method investee of DTE Energy. Pursuant to the terms of those agreements, in October 2018, DTE Energy executed a guarantee agreement with Vector, with a maximum potential payment totaling $7 million at December 31, 2019 , representing 50% of the first-year payment obligations due and payable by NEXUS. The guarantee terminates at the earlier of (i) such time as all of the guaranteed obligations have been fully performed or (ii) 15 years from the date DTE Energy entered into the guarantee. Should NEXUS fail to perform under the terms of these agreements, DTE Energy is required to perform on its behalf. Payments under these guarantees are considered remote. Other Guarantees In certain limited circumstances, the Registrants enter into contractual guarantees. The Registrants may guarantee another entity’s obligation in the event it fails to perform and may provide guarantees in certain indemnification agreements. Finally, the Registrants may provide indirect guarantees for the indebtedness of others. DTE Energy’s guarantees are not individually material with maximum potential payments totaling $56 million at December 31, 2019 . Payments under these guarantees are considered remote. DTE Energy is periodically required to obtain performance surety bonds in support of obligations to various governmental entities and other companies in connection with its operations. As of December 31, 2019 , DTE Energy had $109 million of performance bonds outstanding. In the event that such bonds are called for nonperformance, DTE Energy would be obligated to reimburse the issuer of the performance bond. DTE Energy is released from the performance bonds as the contractual performance is completed and does not believe that a material amount of any currently outstanding performance bonds will be called. Vector Line of Credit In July 2019, DTE Energy, as lender, entered into a revolving term credit facility with Vector, as borrower, in the amount of C$70 million . The credit facility was executed in response to the passage of Canadian regulations requiring oil and gas pipelines to demonstrate their financial ability to respond to a catastrophic event and exists for the sole purpose of satisfying these regulations. Vector may only draw upon the facility if the funds are required to respond to a catastrophic event. The maximum potential payments under the line of credit at December 31, 2019 is $54 million . The funding of a loan under the terms of the credit facility is considered remote. Labor Contracts There are several bargaining units for DTE Energy subsidiaries' approximate 5,300 represented employees, including DTE Electric's approximate 2,800 represented employees. The majority of the represented employees are under contracts that expire in 2021 and 2022 . Purchase Commitments As of December 31, 2019 , the Registrants were party to numerous long-term purchase commitments relating to a variety of goods and services required for their businesses. These agreements primarily consist of fuel supply commitments and renewable energy contracts for the Registrants, as well as energy trading contracts for DTE Energy. The Registrants estimate the following commitments from 2020 through 2051 for DTE Energy, and 2020 through 2039 for DTE Electric, as detailed in the following table: DTE Energy DTE Electric (In millions) 2020 $ 3,152 $ 1,556 2021 1,055 299 2022 561 95 2023 418 96 2024 365 96 2025 and thereafter 1,503 688 $ 7,054 $ 2,830 Utility capital expenditures, expenditures for non-utility businesses, and contributions to equity method investees will be approximately $4.5 billion and $2.6 billion in 2020 for DTE Energy and DTE Electric, respectively. The Registrants have made certain commitments in connection with the estimated 2020 annual capital expenditures and contributions to equity method investees. Bankruptcies DTE Energy's Power and Industrial Projects segment holds ownership interests in, and operates, five generating plants that sell electric output from renewable sources under long-term power purchase agreements with PG&E. PG&E filed for Chapter 11 bankruptcy protection on January 29, 2019. As of December 31, 2019 , PG&Es account is substantially current and outstanding accounts receivable from PG&E are not material. Therefore, DTE Energy determined no reserve was necessary. As of December 31, 2019 , the book value of long-lived assets used in producing electric output for sale to PG&E was approximately $101 million . The Power and Industrial Projects segment also has equity investments, including a note receivable, of approximately $74 million in entities that sell power to PG&E. In January 2019, following the bankruptcy filing, DTE Energy performed an impairment analysis on its long-lived assets. Based on its undiscounted cash flow projections, DTE Energy determined it did no t have an impairment loss as of December 31, 2018. DTE Energy also determined there was no t an other-than-temporary decline in its equity investments. DTE has not identified subsequent facts or circumstances that would cause a change to these conclusions through December 31, 2019. DTE Energy’s assumptions and conclusions may change, and it could have impairment losses if any of the terms of the contracts are not honored by PG&E or the contracts are rejected through the bankruptcy process. Other Contingencies The Registrants are involved in certain other legal, regulatory, administrative, and environmental proceedings before various courts, arbitration panels, and governmental agencies concerning claims arising in the ordinary course of business. These proceedings include certain contract disputes, additional environmental reviews and investigations, audits, inquiries from various regulators, and pending judicial matters. The Registrants cannot predict the final disposition of such proceedings. The Registrants regularly review legal matters and record provisions for claims that they can estimate and are considered probable of loss. The resolution of these pending proceedings is not expected to have a material effect on the Registrants' Consolidated Financial Statements in the periods they are resolved. For a discussion of contingencies related to regulatory matters and derivatives, see Notes 10 and 14 to the Consolidated Financial Statements, " Regulatory Matters " and " Financial and Other Derivative Instruments ," respectively.

Nuclear Operations

Nuclear Operations	12 Months Ended
	Dec. 31, 2019
Nuclear Operations [Abstract]
Nuclear Operations	NUCLEAR OPERATIONS Property Insurance DTE Electric maintains property insurance policies specifically for the Fermi 2 plant. These policies cover such items as replacement power and property damage. NEIL is the primary supplier of the insurance policies. DTE Electric maintains a policy for extra expenses, including replacement power costs necessitated by Fermi 2’s unavailability due to an insured event. This policy has a 12-week waiting period and provides an aggregate $490 million of coverage over a three -year period. DTE Electric has $1.5 billion in primary coverage and $1.25 billion of excess coverage for stabilization, decontamination, debris removal, repair and/or replacement of property, and decommissioning. The combined coverage limit for total property damage is $2.75 billion . The total limit for property damage for non-nuclear events is $2.0 billion and an aggregate of $328 million of coverage for extra expenses over a two -year period. On January 13, 2015, the Terrorism Risk Insurance Program Reauthorization Act of 2015 was signed, extending TRIA through December 31, 2020. For multiple terrorism losses caused by acts of terrorism not covered under the TRIA occurring within one year after the first loss from terrorism, the NEIL policies would make available to all insured entities up to $3.2 billion , plus any amounts recovered from reinsurance, government indemnity, or other sources to cover losses. Under NEIL policies, DTE Electric could be liable for maximum assessments of up to $42 million per event if the loss associated with any one event at any nuclear plant should exceed the accumulated funds available to NEIL. Public Liability Insurance As required by federal law, DTE Electric maintains $450 million of public liability insurance for a nuclear incident. For liabilities arising from a terrorist act outside the scope of TRIA, the policy is subject to one industry aggregate limit of $300 million . Further, under the Price-Anderson Amendments Act of 2005, deferred premium charges up to $138 million could be levied against each licensed nuclear facility, but not more than $20 million per year per facility. Thus, deferred premium charges could be levied against all owners of licensed nuclear facilities in the event of a nuclear incident at any of these facilities. Nuclear Fuel Disposal Costs In accordance with the Federal Nuclear Waste Policy Act of 1982, DTE Electric has a contract with the DOE for the future storage and disposal of spent nuclear fuel from Fermi 2 that required DTE Electric to pay the DOE a fee of 1 mill per kWh of Fermi 2 electricity generated and sold. The fee was a component of nuclear fuel expense. The 1 mill per kWh DOE fee was reduced to zero effective May 16, 2014. The DOE's Yucca Mountain Nuclear Waste Repository program for the acceptance and disposal of spent nuclear fuel was terminated in 2011. DTE Electric is a party in the litigation against the DOE for both past and future costs associated with the DOE's failure to accept spent nuclear fuel under the timetable set forth in the Federal Nuclear Waste Policy Act of 1982. In July 2012, DTE Electric executed a settlement agreement with the federal government for costs associated with the DOE's delay in acceptance of spent nuclear fuel from Fermi 2 for permanent storage. The settlement agreement, including extensions, provides for a claims process and payment of delay-related costs experienced by DTE Electric through 2019. DTE Electric's claims are being settled and paid on a timely basis. The settlement proceeds reduce the cost of the dry cask storage facility assets and provide reimbursement for related operating expenses. DTE Electric currently employs a spent nuclear fuel storage strategy utilizing a fuel pool and a dry cask storage facility. The spent nuclear fuel storage strategy is expected to provide sufficient spent fuel storage capability for the life of the plant as defined by DTE Electric's operating license agreement. The federal government continues to maintain its legal obligation to accept spent nuclear fuel from Fermi 2 for permanent storage. Issues relating to long-term waste disposal policy and to the disposition of funds contributed by DTE Electric ratepayers to the federal waste fund await future governmental action.

Retirement Benefits and Trustee

Retirement Benefits and Trusteed Assets	12 Months Ended
	Dec. 31, 2019
Defined Benefit Plan [Abstract]
Retirement Benefits and Trusteed Assets	RETIREMENT BENEFITS AND TRUSTEED ASSETS DTE Energy's subsidiary, DTE Energy Corporate Services, LLC, sponsors defined benefit pension plans and other postretirement plans covering certain employees of the Registrants. The table below represents the pension and other postretirement benefit plans of each Registrant at December 31, 2019 : Registrants DTE Energy DTE Electric Qualified Pension Plans DTE Energy Company Retirement Plan X X DTE Gas Company Retirement Plan for Employees Covered by Collective Bargaining Agreements X Shenango Inc. Pension Plan X Nonqualified Pension Plans DTE Energy Company Supplemental Retirement Plan X X DTE Energy Company Executive Supplemental Retirement Plan (a) X X DTE Energy Company Supplemental Severance Benefit Plan X Other Postretirement Benefit Plans The DTE Energy Company Comprehensive Non-Health Welfare Plan X X The DTE Energy Company Comprehensive Retiree Group Health Care Plan X X DTE Supplemental Retiree Benefit Plan X X DTE Energy Company Retiree Reimbursement Arrangement Plan X X _____________________________________ (a) Sponsored by the DTE Energy subsidiary, DTE Energy Holding Company. DTE Electric participates in various plans that provide pension and other postretirement benefits for DTE Energy and its affiliates. The plans are sponsored by the LLC. DTE Electric accounts for its participation in DTE Energy's qualified and nonqualified pension plans by applying multiemployer accounting. DTE Electric accounts for its participation in other postretirement benefit plans by applying multiple-employer accounting. Within multiemployer and multiple-employer plans, participants pool plan assets for investment purposes and to reduce the cost of plan administration. The primary difference between plan types is assets contributed in multiemployer plans can be used to provide benefits for all participating employers, while assets contributed within a multiple-employer plan are restricted for use by the contributing employer. As a result of multiemployer accounting treatment, capitalized costs associated with these plans are reflected in Property, plant, and equipment in DTE Electric's Consolidated Statements of Financial Position. The same capitalized costs are reflected as Regulatory assets and liabilities in DTE Energy's Consolidated Statements of Financial Position. In addition, the service cost and non-service cost components are presented in Operation and maintenance in DTE Electric's Consolidated Statements of Operations. The same non-service cost components are presented in Other (Income) and Deductions — Non-operating retirement benefits, net in DTE Energy's Consolidated Statements of Operations. Plan participants of all plans are solely DTE Energy and affiliate participants. Pension Plan Benefits DTE Energy has qualified defined benefit retirement plans for eligible represented and non-represented employees. The plans are noncontributory and provide traditional retirement benefits based on the employee's years of benefit service, average final compensation, and age at retirement. In addition, certain represented and non-represented employees are covered under cash balance provisions that determine benefits on annual employer contributions and interest credits. DTE Energy also maintains supplemental nonqualified, noncontributory, retirement benefit plans for certain management employees. These plans provide for benefits that supplement those provided by DTE Energy’s other retirement plans. Net pension cost for DTE Energy includes the following components: 2019 2018 2017 (In millions) Service cost $ 84 $ 99 $ 92 Interest cost 219 202 214 Expected return on plan assets (325 ) (329 ) (311 ) Amortization of: Net actuarial loss 133 176 176 Prior service cost 1 — 1 Net pension cost $ 112 $ 148 $ 172 2019 2018 (In millions) Other changes in plan assets and benefit obligations recognized in Regulatory assets and Other comprehensive income (loss) Net actuarial loss $ 156 $ 125 Amortization of net actuarial loss (133 ) (176 ) Amortization of prior service cost (1 ) — Total recognized in Regulatory assets and Other comprehensive income (loss) $ 22 $ (51 ) Total recognized in net periodic pension cost, Regulatory assets, and Other comprehensive income (loss) $ 134 $ 97 Estimated amounts to be amortized from Regulatory assets and Accumulated other comprehensive income (loss) into net periodic benefit cost during next fiscal year Net actuarial loss $ 171 $ 131 Prior service cost $ 1 $ 1 The following table reconciles the obligations, assets, and funded status of the plans as well as the amounts recognized as prepaid pension cost or pension liability in DTE Energy's Consolidated Statements of Financial Position at December 31: DTE Energy 2019 2018 (In millions) Accumulated benefit obligation, end of year $ 5,387 $ 4,779 Change in projected benefit obligation Projected benefit obligation, beginning of year $ 5,124 $ 5,576 Service cost 84 99 Interest cost 219 202 Actuarial (gain) loss 719 (438 ) Benefits paid (336 ) (315 ) Projected benefit obligation, end of year $ 5,810 $ 5,124 Change in plan assets Plan assets at fair value, beginning of year $ 4,273 $ 4,636 Actual return on plan assets 888 (233 ) Company contributions 168 185 Benefits paid (336 ) (315 ) Plan assets at fair value, end of year $ 4,993 $ 4,273 Funded status $ (817 ) $ (851 ) Amount recorded as: Current liabilities $ (9 ) $ (14 ) Noncurrent liabilities (808 ) (837 ) $ (817 ) $ (851 ) Amounts recognized in Accumulated other comprehensive income (loss), pre-tax Net actuarial loss $ 153 $ 152 Prior service cost 4 5 $ 157 $ 157 Amounts recognized in Regulatory assets (a) Net actuarial loss $ 1,995 $ 1,973 Prior service credit (12 ) (12 ) $ 1,983 $ 1,961 ______________________________________ (a) See Note 10 to the Consolidated Financial Statements, " Regulatory Matters ." The Registrants' policy is to fund pension costs by contributing amounts consistent with the provisions of the Pension Protection Act of 2006, and additional amounts when it deems appropriate. The following table provides contributions to the qualified pension plans in: 2019 2018 2017 (In millions) DTE Energy $ 150 $ 175 $ 223 DTE Electric $ 100 $ 175 $ 185 During 2019 , DTE Energy contributed the following amounts of DTE Energy common stock to the DTE Energy Company Affiliates Employee Benefit Plans Master Trust: Date Number of Shares Price per Share Amount (In millions) March 5, 2019 814,597 $122.76 $ 100 The above contribution was made on behalf of DTE Electric, for which DTE Electric paid DTE Energy cash consideration of $100 million in March 2019. DTE Energy made additional cash contributions of $50 million to the qualified pension plans in 2019. At the discretion of management, and depending upon financial market conditions, DTE Energy anticipates making up to $185 million in contributions, including $160 million of DTE Electric contributions, to the qualified pension plans in 2020 . DTE Energy's subsidiaries are responsible for their share of qualified and nonqualified pension benefit costs. DTE Electric's allocated portion of pension benefit costs included in capital expenditures and operating and maintenance expense were $93 million for the year ended December 31, 2019 , $120 million for the year ended December 31, 2018 , and $136 million for the year ended December 31, 2017 . These amounts include recognized contractual termination benefit charges, curtailment gains, and settlement charges. At December 31, 2019 , the benefits related to DTE Energy's qualified and nonqualified pension plans expected to be paid in each of the next five years and in the aggregate for the five fiscal years thereafter are as follows: (In millions) 2020 $ 311 2021 319 2022 324 2023 330 2024 334 2025-2029 1,723 Total $ 3,341 Assumptions used in determining the projected benefit obligation and net pension costs of DTE Energy are: 2019 2018 2017 Projected benefit obligation Discount rate 3.28% 4.40% 3.70% Rate of compensation increase 4.98% 4.98% 4.98% Net pension costs Discount rate 4.40% 3.70% 4.25% Rate of compensation increase 4.98% 4.98% 4.65% Expected long-term rate of return on plan assets 7.30% 7.50% 7.50% DTE Energy employs a formal process in determining the long-term rate of return for various asset classes. Management reviews historic financial market risks and returns and long-term historic relationships between the asset classes of equities, fixed income, and other assets, consistent with the widely accepted capital market principle that asset classes with higher volatility generate a greater return over the long-term. Current market factors such as inflation, interest rates, asset class risks, and asset class returns are evaluated and considered before long-term capital market assumptions are determined. The long-term portfolio return is also established employing a consistent formal process, with due consideration of diversification, active investment management, and rebalancing. Peer data is reviewed to check for reasonableness. As a result of this process, the Registrants have long-term rate of return assumptions for the pension plans of 7.10% and other postretirement benefit plans of 7.20% for 2020 . The Registrants believe these rates are a reasonable assumption for the long-term rate of return on plan assets for 2020 given the current investment strategy. The DTE Energy Company Affiliates Employee Benefit Plans Master Trust employs a liability driven investment program whereby the characteristics of plan liabilities are considered when determining investment policy. Risk tolerance is established through consideration of future plan cash flows, plan funded status, and corporate financial considerations. The investment portfolio contains a diversified blend of equity, fixed income, and other investments. Furthermore, equity investments are diversified across U.S. and non-U.S. stocks and large and small market capitalizations. Fixed income investments generally include U.S. Treasuries, other governmental debt, diversified corporate bonds, bank loans, and mortgage-backed securities. Other investments are used to enhance long-term returns while improving portfolio diversification. Derivatives may be utilized in a risk controlled manner, to potentially increase the portfolio beyond the market value of invested assets and/or reduce portfolio investment risk. Investment risk is measured and monitored on an ongoing basis through annual liability measurements, periodic asset/liability studies, and quarterly investment portfolio reviews. Target allocations for DTE Energy's pension plan assets as of December 31, 2019 are listed below: U.S. Large Capitalization (Cap) Equity Securities 16 % U.S. Small Cap and Mid Cap Equity Securities 4 Non-U.S. Equity Securities 15 Fixed Income Securities 42 Hedge Funds and Similar Investments 14 Private Equity and Other 9 100 % The following tables provide the fair value measurement amounts for DTE Energy's pension plan assets at December 31, 2019 and 2018 (a) : December 31, 2019 December 31, 2018 Level 1 Level 2 Other (b) Total Level 1 Level 2 Other (b) Total DTE Energy asset category: (In millions) Short-term Investments (c) $ 99 $ — $ — $ 99 $ — $ 27 $ — $ 27 Equity Securities Domestic (d) 172 — 870 1,042 729 4 — 733 International (e) 387 — 322 709 337 9 240 586 Fixed Income Securities Governmental (f) 569 — — 569 — 868 — 868 Corporate (g) — 1,452 — 1,452 6 1,024 — 1,030 Hedge Funds and Similar Investments (h) 169 — 502 671 88 — 542 630 Private Equity and Other (i) — — 451 451 — — 399 399 DTE Energy Total $ 1,396 $ 1,452 $ 2,145 $ 4,993 $ 1,160 $ 1,932 $ 1,181 $ 4,273 _______________________________________ (a) For a description of levels within the fair value hierarchy, see Note 13 to the Consolidated Financial Statements, " Fair Value ." (b) Amounts represent assets valued at NAV as a practical expedient for fair value. (c) This category predominantly represents certain short-term fixed income securities and money market investments that are managed in separate accounts or commingled funds. Pricing for investments in this category are obtained from quoted prices in actively traded markets or valuations from brokers or pricing services. (d) This category represents portfolios of large, medium and small capitalization domestic equities. Investments in this category include exchange-traded securities for which unadjusted quoted prices can be obtained and exchange-traded securities held in a commingled fund classified as NAV assets. (e) This category primarily consists of portfolios of non-U.S. developed and emerging market equities. Investments in this category are exchange-traded securities whereby unadjusted quoted prices can be obtained. Exchange-traded securities held in a commingled fund are classified as NAV assets. (f) This category includes U.S. Treasuries, bonds, and other governmental debt. Pricing for investments in this category is obtained from quoted prices in actively traded markets and quotations from broker or pricing services. (g) This category primarily consists of corporate bonds from diversified industries, bank loans, and mortgage backed securities. Pricing for investments in this category is obtained from quoted prices in actively traded markets and quotations from broker or pricing services. (h) This category utilizes a diversified group of strategies that attempt to capture financial market inefficiencies and includes publicly traded mutual funds, commingled funds and limited partnership funds. Pricing for mutual funds in this category is obtained from quoted prices in actively traded markets. Commingled funds and limited partnership funds are classified as NAV assets. (i) This category includes a diversified group of funds and strategies that primarily invests in private equity partnerships. This category also includes investments in real estate and private debt. All pricing for investments in this category are classified as NAV assets. The pension trust holds debt and equity securities directly and indirectly through commingled funds. Exchange-traded debt and equity securities held directly are valued using quoted market prices in actively traded markets. The commingled funds hold exchange-traded equity or debt securities and are valued based on stated NAVs. Non-exchange traded fixed income securities are valued by the trustee based upon quotations available from brokers or pricing services. A primary price source is identified by asset type, class, or issue for each security. The trustee monitors prices supplied by pricing services and may use a supplemental price source or change the primary price source of a given security if the trustee challenges an assigned price and determines that another price source is considered preferable. DTE Energy has obtained an understanding of how these prices are derived, including the nature and observability of the inputs used in deriving such prices. Other Postretirement Benefits The Registrants participate in defined benefit plans sponsored by the LLC that provide certain other postretirement health care and life insurance benefits for employees who are eligible for these benefits. The Registrants' policy is to fund certain trusts to meet its other postretirement benefit obligations. DTE Energy did not make any contributions to these trusts during 2019 and does not anticipate making any contributions to the trusts in 2020 . DTE Energy and DTE Electric offer a defined contribution VEBA for eligible represented and non-represented employees, in lieu of defined benefit post-employment health care benefits. The Registrants allocate a fixed amount per year to an account in a defined contribution VEBA for each employee. These accounts are managed either by the Registrant (for non-represented and certain represented groups) or by the Utility Workers of America for Local 223 employees. DTE Energy contributions to the VEBA for these accounts were $13 million in 2019 , $11 million in 2018 , and $8 million in 2017 , including DTE Electric contributions of $6 million in 2019 and $5 million in 2018 and 2017 . The Registrants also contribute a fixed amount to a Retiree Reimbursement Account, for certain non-represented and represented retirees, spouses, and surviving spouses when the youngest of the retiree's covered household becomes eligible for Medicare Part A based on age. The amount of the annual allocation to each participant is determined by the employee's retirement date and increases each year for each eligible participant at the lower of the rate of medical inflation or 2% . Net other postretirement credit for DTE Energy includes the following components: 2019 2018 2017 (In millions) Service cost $ 22 $ 27 $ 27 Interest cost 70 69 73 Expected return on plan assets (96 ) (143 ) (130 ) Amortization of: Net actuarial loss 12 11 13 Prior service credit (9 ) — (14 ) Net other postretirement credit $ (1 ) $ (36 ) $ (31 ) 2019 2018 (In millions) Other changes in plan assets and accumulated postretirement benefit obligation recognized in Regulatory assets and Other comprehensive income (loss) Net actuarial (gain) loss $ 34 $ (8 ) Amortization of net actuarial loss (12 ) (11 ) Prior service credit (53 ) (44 ) Amortization of prior service credit 9 — Total recognized in Regulatory assets and Other comprehensive income (loss) $ (22 ) $ (63 ) Total recognized in net periodic benefit cost, Regulatory assets, and Other comprehensive income (loss) $ (23 ) $ (99 ) Estimated amounts to be amortized from Regulatory assets and Accumulated other comprehensive income (loss) into net periodic benefit cost during next fiscal year Net actuarial loss $ 16 $ 12 Prior service credit $ (19 ) $ (9 ) Net other postretirement credit for DTE Electric includes the following components: 2019 2018 2017 (In millions) Service cost $ 16 $ 20 $ 20 Interest cost 53 53 56 Expected return on plan assets (65 ) (98 ) (90 ) Amortization of: Net actuarial loss 5 8 8 Prior service credit (7 ) — (10 ) Net other postretirement cost (credit) $ 2 $ (17 ) $ (16 ) 2019 2018 (In millions) Other changes in plan assets and accumulated postretirement benefit obligation recognized in Regulatory assets Net actuarial (gain) loss $ 41 $ (46 ) Amortization of net actuarial loss (5 ) (8 ) Prior service cost (33 ) — Amortization of prior service (cost) credit 7 (35 ) Total recognized in Regulatory assets $ 10 $ (89 ) Total recognized in net periodic benefit cost and Regulatory assets $ 12 $ (106 ) Estimated amounts to be amortized from Regulatory assets into net periodic benefit cost during next fiscal year Net actuarial loss $ 11 $ 5 Prior service credit $ (14 ) $ (7 ) The following table reconciles the obligations, assets, and funded status of the plans including amounts recorded as Accrued postretirement liability in the Registrants' Consolidated Statements of Financial Position at December 31: DTE Energy DTE Electric 2019 2018 2019 2018 (In millions) Change in accumulated postretirement benefit obligation Accumulated postretirement benefit obligation, beginning of year $ 1,645 $ 1,910 $ 1,247 $ 1,470 Service cost 22 27 16 20 Interest cost 70 69 53 53 Plan amendments (53 ) (44 ) (33 ) (35 ) Actuarial (gain) loss 153 (227 ) 118 (196 ) Benefits paid (86 ) (90 ) (64 ) (65 ) Accumulated postretirement benefit obligation, end of year $ 1,751 $ 1,645 $ 1,337 $ 1,247 Change in plan assets Plan assets at fair value, beginning of year $ 1,689 $ 1,848 $ 1,158 $ 1,272 Actual return on plan assets 215 (75 ) 141 (52 ) Benefits paid (85 ) (84 ) (63 ) (62 ) Plan assets at fair value, end of year $ 1,819 $ 1,689 $ 1,236 $ 1,158 Funded status $ 68 $ 44 $ (101 ) $ (89 ) Amount recorded as: Noncurrent assets $ 69 $ 45 $ 266 $ 189 Current liabilities (1 ) (1 ) — — Noncurrent liabilities — — (367 ) (278 ) $ 68 $ 44 $ (101 ) $ (89 ) Amounts recognized in Accumulated other comprehensive income (loss), pre-tax Net actuarial (gain) loss $ (8 ) $ 1 $ — $ — $ (8 ) $ 1 $ — $ — Amounts recognized in Regulatory assets (a) Net actuarial loss $ 289 $ 257 $ 193 $ 156 Prior service credit (88 ) (44 ) (62 ) (35 ) $ 201 $ 213 $ 131 $ 121 ______________________________________ (a) See Note 10 to the Consolidated Financial Statements, " Regulatory Matters ." At December 31, 2019 , the benefits expected to be paid, including prescription drug benefits, in each of the next five years and in the aggregate for the five fiscal years thereafter for the Registrants are as follows: DTE Energy DTE Electric (In millions) 2020 $ 84 $ 64 2021 88 67 2022 92 70 2023 94 72 2024 96 73 2025-2029 496 378 Total $ 950 $ 724 Assumptions used in determining the accumulated postretirement benefit obligation and net other postretirement benefit costs of the Registrants are: 2019 2018 2017 Accumulated postretirement benefit obligation Discount rate 3.29% 4.40% 3.70% Health care trend rate pre- and post- 65 6.75 / 7.25% 6.75 / 7.25% 6.75 / 7.25% Ultimate health care trend rate 4.50% 4.50% 4.50% Year in which ultimate reached pre- and post- 65 2032 2031 2030 Other postretirement benefit costs Discount rate 4.40% 3.70% 4.25% Expected long-term rate of return on plan assets 7.30% 7.75% 7.75% Health care trend rate pre- and post- 65 6.75 / 7.25% 6.75 / 7.25% 6.50 / 6.75% Ultimate health care trend rate 4.50% 4.50% 4.50% Year in which ultimate reached pre- and post- 65 2031 2030 2028 A one percentage point increase in health care cost trend rates would have increased the total service cost and interest cost components of benefit costs for DTE Energy by $3 million , including $2 million for DTE Electric, in 2019 and would have increased the accumulated benefit obligation for DTE Energy by $62 million , including $44 million for DTE Electric, at December 31, 2019 . A one percentage point decrease in the health care cost trend rates would have decreased the total service and interest cost components of benefit costs for DTE Energy by $3 million , including $2 million for DTE Electric, in 2019 and would have decreased the accumulated benefit obligation for DTE Energy by $54 million , including $39 million for DTE Electric, at December 31, 2019 . The process used in determining the long-term rate of return on assets for the other postretirement benefit plans is similar to that previously described for the pension plans. The DTE Energy Company Master VEBA Trust employs a liability driven investment program whereby the characteristics of plan liabilities are considered when determining investment policy. Risk tolerance is established through consideration of future plan cash flows, plan funded status, and corporate financial considerations. The investment portfolio contains a diversified blend of equity, fixed income, and other investments. Furthermore, equity investments are diversified across U.S. and non-U.S. stocks and large and small market capitalizations. Fixed income investments generally include U.S. Treasuries, other governmental debt, diversified corporate bonds, bank loans, and mortgage-backed securities. Other investments are used to enhance long-term returns while improving portfolio diversification. Derivatives may be utilized in a risk controlled manner to potentially increase the portfolio beyond the market value of invested assets and/or reduce portfolio investment risk. Investment risk is measured and monitored on an ongoing basis through annual liability measurements, periodic asset/liability studies, and quarterly investment portfolio reviews. Target allocations for the Registrants' other postretirement benefit plan assets as of December 31, 2019 are listed below: U.S. Large Cap Equity Securities 16 % U.S. Small Cap and Mid Cap Equity Securities 3 Non-U.S. Equity Securities 16 Fixed Income Securities 37 Hedge Funds and Similar Investments 14 Private Equity and Other 14 100 % The following tables provide the fair value measurement amounts for the Registrants' other postretirement benefit plan assets at December 31, 2019 and 2018 (a) : December 31, 2019 December 31, 2018 Level 1 Level 2 Other (b) Total Level 1 Level 2 Other (b) Total DTE Energy asset category: (In millions) Short-term Investments (c) $ 80 $ — $ — $ 80 $ 14 $ 2 $ — $ 16 Equity Securities Domestic (d) 51 — 273 324 300 — — 300 International (e) 182 — 89 271 234 — 67 301 Fixed Income Securities Governmental (f) 74 — — 74 — 85 — 85 Corporate (g) — 256 251 507 11 265 130 406 Hedge Funds and Similar Investments (h) 71 — 182 253 97 — 203 300 Private Equity and Other (i) — — 310 310 — — 281 281 DTE Energy Total $ 458 $ 256 $ 1,105 $ 1,819 $ 656 $ 352 $ 681 $ 1,689 DTE Electric asset category: Short-term Investments (c) $ 55 $ — $ — $ 55 $ 10 $ 1 $ — $ 11 Equity Securities Domestic (d) 34 — 185 219 206 — — 206 International (e) 124 — 60 184 163 — 45 208 Fixed Income Securities Governmental (f) 48 — — 48 — 53 — 53 Corporate (g) — 168 176 344 7 179 92 278 Hedge Funds and Similar Investments (h) 49 — 123 172 68 — 139 207 Private Equity and Other (i) — — 214 214 — — 195 195 DTE Electric Total $ 310 $ 168 $ 758 $ 1,236 $ 454 $ 233 $ 471 $ 1,158 _______________________________________ (a) For a description of levels within the fair value hierarchy see Note 13 to the Consolidated Financial Statements, " Fair Value ." (b) Amounts represent assets valued at NAV as a practical expedient for fair value. (c) This category predominantly represents certain short-term fixed income securities and money market investments that are managed in separate accounts or commingled funds. Pricing for investments in this category are obtained from quoted prices in actively traded markets or valuations from brokers or pricing services. (d) This category represents portfolios of large, medium and small capitalization domestic equities. Investments in this category include exchange-traded securities for which unadjusted quoted prices can be obtained and exchange-traded securities held in a commingled fund classified as NAV assets. (e) This category primarily consists of portfolios of non-U.S. developed and emerging market equities. Investments in this category are exchange-traded securities whereby unadjusted quoted prices can be obtained. Exchange-traded securities held in a commingled fund are classified as NAV assets. (f) This category includes U.S. Treasuries, bonds and other governmental debt. Pricing for investments in this category is obtained from quoted prices in actively traded markets and quotations from broker or pricing services. (g) This category primarily consists of corporate bonds from diversified industries, bank loans, and mortgage backed securities. Pricing for investments in this category is obtained from quoted prices in actively traded markets and quotations from broker or pricing services. Non-exchange traded securities and exchange-traded securities held in commingled funds are classified as NAV assets. (h) This category utilizes a diversified group of strategies that attempt to capture financial market inefficiencies and includes publicly traded mutual funds, commingled funds and limited partnership funds. Pricing for mutual funds in this category is obtained from quoted prices in actively traded markets. Commingled funds and limited partnership funds are classified as NAV assets. (i) This category includes a diversified group of funds and strategies that primarily invests in private equity partnerships. This category also includes investments in real estate and private debt. All investments in this category are classified as NAV assets. The DTE Energy Company Master VEBA Trust holds debt and equity securities directly and indirectly through commingled funds. Exchange-traded debt and equity securities held directly are valued using quoted market prices in actively traded markets. The commingled funds hold exchange-traded equity or debt securities and are valued based on NAVs. Non-exchange traded fixed income securities are valued by the trustee based upon quotations available from brokers or pricing services. A primary price source is identified by asset type, class, or issue for each security. The trustee monitors prices supplied by pricing services and may use a supplemental price source or change the primary price source of a given security if the trustee challenges an assigned price and determines that another price source is considered preferable. The Registrants have obtained an understanding of how these prices are derived, including the nature and observability of the inputs used in deriving such prices. Defined Contribution Plans The Registrants also sponsor defined contribution retirement savings plans. Participation in one of these plans is available to substantially all represented and non-represented employees. For substantially all employees, the Registrants match employee contributions up to certain predefined limits based upon eligible compensation and the employee’s contribution rate. Additionally, for eligible represented and non-represented employees who do not participate in the Pension Plans, the Registrants annually contribute an amount equivalent to 4% ( 8% for certain DTE Gas represented employees) of an employee's eligible pay to the employee's defined contribution retirement savings plan. For DTE Energy, the cost of these plans was $65 million , $61 million , and $57 million for the years ended December 31, 2019 , 2018 , and 2017 , respectively. For DTE Electric, the cost of these plans was $31 million , $29 million , and $27 million for the years ended December 31, 2019 , 2018 , and 2017 , respectively.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2019
Share-based Payment Arrangement, Noncash Expense [Abstract]
Stock-Based Compensation	STOCK-BASED COMPENSATION DTE Energy’s stock incentive program permits the grant of incentive stock options, non-qualifying stock options, stock awards, performance shares, and performance units to employees and members of its Board of Directors. As a result of a stock award, a settlement of an award of performance shares, or by exercise of a participant’s stock option, DTE Energy may deliver common stock from its authorized but unissued common stock and/or from outstanding common stock acquired by or on behalf of DTE Energy in the name of the participant. Key provisions of the stock incentive program are: • Authorized limit is 16,500,000 shares of common stock; • Prohibits the grant of a stock option with an exercise price that is less than the fair market value of DTE Energy’s stock on the date of the grant; and • Imposes the following award limits to a single participant in a single calendar year, (1) options for more than 500,000 shares of common stock; (2) stock awards for more than 150,000 shares of common stock; (3) performance share awards for more than 300,000 shares of common stock (based on the maximum payout under the award); or (4) more than 1,000,000 performance units, which have a face amount of $1.00 each. DTE Energy records compensation expense at fair value over the vesting period for all awards it grants. The following table summarizes the components of stock-based compensation for DTE Energy: 2019 2018 2017 (In millions) Stock-based compensation expense $ 71 $ 64 $ 58 Tax benefit $ 13 $ 13 $ 23 Stock-based compensation cost capitalized in Property, plant, and equipment $ 16 $ 11 $ 9 Stock Options Options are exercisable according to the terms of the individual stock option award agreements and expire ten years after the date of the grant. The option exercise price equals the fair value of the stock on the date that the option was granted. Stock options vest ratably over a three -year period. There were no options granted and no options expensed during 2019 , 2018 , or 2017 . The intrinsic value of options outstanding and options exercised for the years ended December 31, 2019 , 2018 , and 2017 were not material. Restricted Stock Awards Stock awards granted under the plan are restricted for varying periods, generally for three years . Participants have all rights of a shareholder with respect to a stock award, including the right to receive dividends and vote the shares. Prior to vesting in stock awards, the participant: (i) may not sell, transfer, pledge, exchange, or otherwise dispose of shares; (ii) shall not retain custody of the share certificates; and (iii) will deliver to DTE Energy a stock power with respect to each stock award upon request. The stock awards are recorded at cost that approximates fair value on the date of grant. The cost is amortized to compensation expense over the vesting period. The fair value of awards vested were not material for the years ended December 31, 2019 , 2018 , and 2017 . Compensation cost charged against income was $11 million for the years ended December 31, 2019 , 2018 , and 2017 . Performance Share Awards Performance shares awarded under the plan are for a specified number of shares of DTE Energy common stock that entitle the holder to receive a cash payment, shares of DTE Energy common stock, or a combination thereof. The final value of the award is determined by the achievement of certain performance objectives and market conditions. The awards vest at the end of a specified period, usually three years . Awards granted in 2019 , 2018 , and 2017 were primarily deemed to be equity awards. The DTE Energy stock price and number of probable shares attributable to market conditions for such equity awards are fair valued only at the grant date. DTE Energy accounts for performance share awards by accruing compensation expense over the vesting period based on: (i) the number of shares expected to be paid which is based on the probable achievement of performance objectives; and (ii) the closing stock price market value. The settlement of the award is based on the closing price at the settlement date. DTE Energy recorded compensation expense for performance share awards as follows: 2019 2018 2017 (In millions) Compensation expense $ 60 $ 53 $ 47 Cash settlements (a) $ 19 $ 13 $ 15 Stock settlements (a) $ 79 $ 39 $ 66 _______________________________________ (a) Sum of cash and stock settlements approximates the intrinsic value of the awards. During the vesting period, the recipient of a performance share award has no shareholder rights. During the period beginning on the date the performance shares are awarded and ending on the certification date of the performance objectives, the number of performance shares awarded will be increased, assuming full dividend reinvestment at the fair market value on the dividend payment date. The cumulative number of performance shares will be adjusted to determine the final payment based on the performance objectives achieved. Performance share awards are nontransferable and are subject to risk of forfeiture. The following table summarizes DTE Energy’s performance share activity for the period ended December 31, 2019 : Performance Shares Weighted Average Balance at December 31, 2018 1,286,686 $ 97.17 Grants 446,579 $ 115.85 Forfeitures (44,044 ) $ 102.42 Payouts (463,190 ) $ 88.53 Balance at December 31, 2019 1,226,031 $ 107.35 Unrecognized Compensation Costs As of December 31, 2019 , DTE Energy's total unrecognized compensation cost related to non-vested stock incentive plan arrangements and the weighted average recognition period was as follows: Unrecognized Weighted Average (In millions) (In years) Stock awards $ 19 1.57 Performance shares 62 1.05 $ 81 1.17 Allocated Stock-Based Compensation DTE Electric received an allocation of costs from DTE Energy associated with stock-based compensation. DTE Electric's allocation for 2019 , 2018 , and 2017 for stock-based compensation expense was $43 million , $38 million , and $34 million , respectively.

Segment and Related Information

Segment and Related Information	12 Months Ended
	Dec. 31, 2019
Segment Reporting [Abstract]
Segment and Related Information	SEGMENT AND RELATED INFORMATION DTE Energy sets strategic goals, allocates resources, and evaluates performance based on the following structure: Electric segment consists principally of DTE Electric, which is engaged in the generation, purchase, distribution, and sale of electricity to approximately 2.2 million residential, commercial, and industrial customers in southeastern Michigan. Gas segment consists principally of DTE Gas, which is engaged in the purchase, storage, transportation, distribution, and sale of natural gas to approximately 1.3 million residential, commercial, and industrial customers throughout Michigan and the sale of storage and transportation capacity. Gas Storage and Pipelines is primarily engaged in services related to the gathering, transportation, and storage of natural gas. Power and Industrial Projects is comprised primarily of projects that deliver energy and utility-type products and services to industrial, commercial, and institutional customers, produce reduced emissions fuel, and sell electricity and pipeline-quality gas from renewable energy projects. Energy Trading consists of energy marketing and trading operations. Corporate and Other includes various holding company activities, holds certain non-utility debt, and holds energy-related investments. The federal income tax provisions or benefits of DTE Energy’s subsidiaries are determined on an individual company basis and recognize the tax benefit of tax credits and net operating losses, if applicable. The state and local income tax provisions of the utility subsidiaries are determined on an individual company basis and recognize the tax benefit of various tax credits and net operating losses, if applicable. The subsidiaries record federal, state, and local income taxes payable to or receivable from DTE Energy based on the federal, state, and local tax provisions of each company. Inter-segment billing for goods and services exchanged between segments is based upon tariffed or market-based prices of the provider and primarily consists of the sale of reduced emissions fuel, power sales, and natural gas sales in the following segments: Year Ended December 31, 2019 2018 2017 (In millions) Electric $ 56 $ 52 $ 48 Gas 12 12 8 Gas Storage and Pipelines 27 36 42 Power and Industrial Projects 596 642 569 Energy Trading 22 27 35 Corporate and Other 2 2 2 $ 715 $ 771 $ 704 Financial data of DTE Energy's business segments follows: Electric Gas Gas Storage and Pipelines Power and Industrial Projects Energy Trading Corporate and Other Reclassifications Total (In millions) 2019 Operating Revenues — Utility operations $ 5,224 1,482 — — — — (68 ) $ 6,638 Operating Revenues — Non-utility operations $ 5 — 501 1,560 4,610 2 (647 ) $ 6,031 Depreciation and amortization $ 949 144 94 69 6 1 — $ 1,263 Interest expense $ 315 78 73 33 8 266 (132 ) $ 641 Interest income $ (2 ) (6 ) (8 ) (9 ) (4 ) (120 ) 132 $ (17 ) Equity in earnings of equity method investees $ 1 2 97 14 — (3 ) — $ 111 Income Tax Expense (Benefit) $ 137 62 74 (63 ) 17 (75 ) — $ 152 Net Income (Loss) Attributable to DTE Energy Company $ 714 185 204 133 49 (116 ) — $ 1,169 Investment in equity method investees $ 5 11 1,685 130 — 31 — $ 1,862 Capital expenditures and acquisitions $ 2,368 530 2,510 54 5 — — $ 5,467 Goodwill $ 1,208 743 470 26 17 — — $ 2,464 Total Assets $ 24,617 5,717 4,832 537 798 7,679 (2,298 ) $ 41,882 Electric Gas Gas Storage and Pipelines Power and Industrial Projects Energy Trading Corporate and Other Reclassifications Total (In millions) 2018 Operating Revenues — Utility operations $ 5,298 1,436 — — — — (64 ) $ 6,670 Operating Revenues — Non-utility operations $ — 485 2,204 5,557 3 (707 ) $ 7,542 Depreciation and amortization $ 836 133 82 67 5 1 — $ 1,124 Interest expense $ 283 70 68 31 6 220 (119 ) $ 559 Interest income $ — (6 ) (9 ) (9 ) (3 ) (104 ) 119 $ (12 ) Equity in earnings of equity method investees $ — 2 123 3 — 4 — $ 132 Income Tax Expense (Benefit) $ 193 67 68 (195 ) 13 (48 ) — $ 98 Net Income (Loss) Attributable to DTE Energy Company $ 664 150 235 161 39 (129 ) — $ 1,120 Investment in equity method investees $ 7 12 1,585 134 — 33 — $ 1,771 Capital expenditures and acquisitions $ 1,979 460 176 91 5 2 — $ 2,713 Goodwill $ 1,208 743 299 26 17 — — $ 2,293 Total Assets $ 22,501 5,378 3,161 495 909 6,153 (2,309 ) $ 36,288 Electric Gas Gas Storage and Pipelines Power and Industrial Projects Energy Trading Corporate and Other Reclassifications Total (In millions) 2017 Operating Revenues — Utility operations $ 5,102 1,388 — — — — (56 ) $ 6,434 Operating Revenues — Non-utility operations $ — — 453 2,089 4,277 2 (648 ) $ 6,173 Depreciation and amortization $ 753 123 76 72 5 1 — $ 1,030 Interest expense $ 274 65 77 29 5 192 (106 ) $ 536 Interest income $ — (7 ) (14 ) (7 ) (2 ) (88 ) 106 $ (12 ) Equity in earnings of equity method investees $ 1 2 90 9 — — — $ 102 Income Tax Expense (Benefit) (a) $ 321 78 (30 ) (195 ) 49 (48 ) — $ 175 Net Income (Loss) Attributable to DTE Energy Company $ 606 146 275 138 72 (103 ) — $ 1,134 Investment in equity method investees $ 7 11 879 150 — 26 — $ 1,073 Capital expenditures and acquisitions $ 1,574 463 137 56 7 13 — $ 2,250 Goodwill $ 1,208 743 299 26 17 — — $ 2,293 Total Assets $ 21,163 5,072 2,594 593 725 5,324 (1,704 ) $ 33,767 _____________________________________ (a) Includes Income Tax Expense (Benefit) of $(5) million , $(115) million , $(21) million , $2 million , and $34 million for Electric — non-utility, Gas Storage and Pipelines, Power and Industrial Projects, Energy Trading, and Corporate and Other, respectively, related to the enactment of the TCJA.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2019
Related Party Transactions [Abstract]
Related Party Transactions	RELATED PARTY TRANSACTIONS DTE Energy enters into related party transactions with certain equity method investees, primarily between DTE Gas and NEXUS. DTE Gas is party to a 15 -year capacity lease agreement with NEXUS for the transportation of natural gas. Under the lease agreement, DTE Gas provides firm pipeline capacity in the DTE Gas system in order for NEXUS to provide service to its customers from an interconnect between NEXUS and DTE Gas. NEXUS is charged a fixed daily pipeline reservation charge. DTE Gas operating revenues from this agreement was $32 million and $6 million in 2019 and 2018, respectively. DTE Gas is also party to a 15 -year service agreement with NEXUS for the transportation of natural gas. Under the service agreement, NEXUS provides firm pipeline capacity to transport natural gas to service DTE Gas customers. DTE Gas incurs a firm daily pipeline reservation charge, which totaled $21 million and $2 million in 2019 and 2018, respectively. These expenses are included in Fuel, purchased power, and gas - utility on the Consolidated Statements of Operations and are recovered through the GCR mechanism. Other related party transactions with equity method investees include transactions with Vector Pipeline and Millennium Pipeline. These transactions were not material for the years ended December 31, 2019, 2018, and 2017. DTE Electric has agreements with affiliated companies to sell energy for resale, purchase fuel and power, provide fuel supply services, and provide power plant operation and maintenance services. DTE Electric has agreements with certain DTE Energy affiliates where DTE Electric charges the affiliates for their use of the shared capital assets of DTE Electric. A shared services company accumulates various corporate support services expenses and charges various subsidiaries of DTE Energy, including DTE Electric. DTE Electric records federal, state, and local income taxes payable to or receivable from DTE Energy based on its federal, state, and local tax provisions. The following is a summary of DTE Electric's transactions with affiliated companies: 2019 2018 2017 (In millions) Revenues Energy sales $ 10 $ 9 $ 9 Other services $ 5 $ 4 $ 4 Shared capital assets $ 47 $ 43 $ 39 Costs Fuel and purchased power $ 9 $ 7 $ 6 Other services and interest $ 23 $ 33 $ (2 ) Corporate expenses, net $ 372 $ 377 $ 370 Other Dividends declared $ 494 $ 461 $ 432 Dividends paid $ 494 $ 461 $ 432 Capital contribution from DTE Energy $ 180 $ 325 $ 100 DTE Electric's Accounts receivable and Accounts payable related to Affiliates are payable upon demand and are generally settled in cash within a monthly business cycle. Notes receivable and Short-term borrowings related to Affiliates are subject to a credit agreement with DTE Energy whereby short-term excess cash or cash shortfalls are remitted to or funded by DTE Energy. This credit arrangement involves the charge and payment of interest at market-based rates. Refer to DTE Electric's Consolidated Statements of Financial Position for affiliate balances at December 31, 2019 and 2018 . There were no contributions made by DTE Electric to the DTE Energy Foundation for the years ended December 31, 2019 and 2018 . There were $7 million in charitable contributions made by DTE Electric to the DTE Energy Foundation for the year ended December 31, 2017 . The DTE Energy Foundation is a non-consolidated not-for-profit private foundation, the purpose of which is to contribute and assist charitable organizations. See the following notes for other related party transactions impacting DTE Electric’s Consolidated Financial Statements: Note Title 1 Organization and Basis of Presentation 21 Retirement Benefits and Trusteed Assets 22 Stock-Based Compensation

Supplementary Quarterly Financi

Supplementary Quarterly Financial Information (Unaudited)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
Supplementary Quarterly Financial Information (Unaudited)	SUPPLEMENTARY QUARTERLY FINANCIAL INFORMATION (UNAUDITED) DTE Energy Quarterly earnings per share may not equal full year totals, since quarterly computations are based on weighted average common shares outstanding during each quarter. First Second Third Fourth Year (In millions, except per share amounts) 2019 Operating Revenues $ 3,514 $ 2,888 $ 3,119 $ 3,148 $ 12,669 Operating Income $ 542 $ 300 $ 450 $ 415 $ 1,707 Net Income Attributable to DTE Energy Company $ 401 $ 182 $ 319 $ 267 $ 1,169 Basic Earnings per Share $ 2.20 $ 0.99 $ 1.74 $ 1.40 $ 6.32 Diluted Earnings per Share $ 2.19 $ 0.99 $ 1.73 $ 1.40 $ 6.31 2018 Operating Revenues $ 3,753 $ 3,159 $ 3,550 $ 3,750 $ 14,212 Operating Income $ 504 $ 329 $ 429 $ 332 $ 1,594 Net Income Attributable to DTE Energy Company $ 361 $ 234 $ 334 $ 191 $ 1,120 Basic Earnings per Share $ 2.01 $ 1.29 $ 1.84 $ 1.05 $ 6.18 Diluted Earnings per Share $ 2.00 $ 1.29 $ 1.84 $ 1.05 $ 6.17 DTE Electric First Second Third Fourth Year (In millions) 2019 Operating Revenues $ 1,235 $ 1,190 $ 1,519 $ 1,280 $ 5,224 Operating Income $ 226 $ 223 $ 440 $ 224 $ 1,113 Net Income $ 147 $ 133 $ 307 $ 129 $ 716 2018 Operating Revenues $ 1,205 $ 1,276 $ 1,521 $ 1,296 $ 5,298 Operating Income $ 253 $ 269 $ 444 $ 168 $ 1,134 Net Income $ 140 $ 163 $ 305 $ 56 $ 664

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2019
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Schedule II - Valuation and Qualifying Accounts	DTE Energy Company Schedule II — Valuation and Qualifying Accounts Year Ending December 31, 2019 2018 2017 (In millions) Allowance for Doubtful Accounts (shown as deduction from Accounts receivable in DTE Energy's Consolidated Statements of Financial Position) Balance at Beginning of Period $ 91 $ 49 $ 41 Additions: Charged to costs and expenses 111 140 80 Charged to other accounts (a) 56 55 26 Deductions (b) (167 ) (153 ) (98 ) Balance at End of Period $ 91 $ 91 $ 49 _______________________________________ (a) Collection of accounts previously written off. (b) Uncollectible accounts written off. DTE Electric Company Schedule II — Valuation and Qualifying Accounts Year Ending December 31, 2019 2018 2017 (In millions) Allowance for Doubtful Accounts (shown as deduction from Accounts receivable in DTE Electric's Consolidated Statements of Financial Position) Balance at Beginning of Period $ 53 $ 31 $ 25 Additions: Charged to costs and expenses 65 85 55 Charged to other accounts (a) 36 36 14 Deductions (b) (108 ) (99 ) (63 ) Balance at End of Period $ 46 $ 53 $ 31 _______________________________________ (a) Collection of accounts previously written off. (b) Uncollectible accounts written off.

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying Consolidated Financial Statements of the Registrants are prepared using accounting principles generally accepted in the United States of America. These accounting principles require management to use estimates and assumptions that impact reported amounts of assets, liabilities, revenues and expenses, and the disclosure of contingent assets and liabilities. Actual results may differ from the Registrants' estimates. The information in these combined notes relates to each of the Registrants as noted in the Index of Combined Notes to Consolidated Financial Statements. However, DTE Electric does not make any representation as to information related solely to DTE Energy or the subsidiaries of DTE Energy other than itself.
Reclassification	Certain prior year balances for the Registrants were reclassified to match the current year's Consolidated Financial Statements presentation.
Principles of Consolidation	Principles of Consolidation The Registrants consolidate all majority-owned subsidiaries and investments in entities in which they have controlling influence. Non-majority owned investments are accounted for using the equity method when the Registrants are able to significantly influence the operating policies of the investee. When the Registrants do not influence the operating policies of an investee, the cost method is used. These Consolidated Financial Statements also reflect the Registrants' proportionate interests in certain jointly-owned utility plants. The Registrants eliminate all intercompany balances and transactions. The Registrants evaluate whether an entity is a VIE whenever reconsideration events occur. The Registrants consolidate VIEs for which they are the primary beneficiary. If a Registrant is not the primary beneficiary and an ownership interest is held, the VIE is accounted for under the equity method of accounting. When assessing the determination of the primary beneficiary, a Registrant considers all relevant facts and circumstances, including: the power, through voting or similar rights, to direct the activities of the VIE that most significantly impact the VIE's economic performance and the obligation to absorb the expected losses and/or the right to receive the expected returns of the VIE. The Registrants perform ongoing reassessments of all VIEs to determine if the primary beneficiary status has changed. Legal entities within DTE Energy's Power and Industrial Projects segment enter into long-term contractual arrangements with customers to supply energy-related products or services. The entities are generally designed to pass-through the commodity risk associated with these contracts to the customers, with DTE Energy retaining operational and customer default risk. These entities generally are VIEs and consolidated when DTE Energy is the primary beneficiary. In addition, DTE Energy has interests in certain VIEs through which control of all significant activities is shared with partners, and therefore are generally accounted for under the equity method. DTE Energy currently owns an 85% interest in SGG, which owns and operates midstream natural gas assets. SGG has contracts through which certain construction risk is designed to pass-through to the customers, with DTE Energy retaining operational and customer default risk. SGG is a VIE with DTE Energy as the primary beneficiary. The Registrants have variable interests in NEXUS, which include DTE Energy's 50% ownership interest and DTE Electric's transportation services contract. NEXUS is a joint venture which owns a 256-mile pipeline to transport Utica and Marcellus shale gas to Ohio, Michigan, and Ontario market centers. NEXUS also owns Generation Pipeline, LLC, a 23-mile regulated pipeline system located in northern Ohio, which was acquired in September 2019. Refer to Note 4, "Acquisitions," for additional information. NEXUS is a VIE as it has insufficient equity at risk to finance its activities. The Registrants are not the primary beneficiaries, as the power to direct significant activities is shared between the owners of the equity interests. DTE Energy accounts for its ownership interest in NEXUS under the equity method. The Registrants hold ownership interests in certain limited partnerships. The limited partnerships include investment funds which support regional development and economic growth, as well as an operational business providing energy-related products. These entities are generally VIEs as a result of certain characteristics of the limited partnership voting rights. The ownership interests are accounted for under the equity method as the Registrants are not the primary beneficiaries. DTE Energy has variable interests in VIEs through certain of its long-term purchase and sale contracts. DTE Electric has variable interests in VIEs through certain of its long-term purchase contracts. As of December 31, 2019 , the carrying amount of assets and liabilities in DTE Energy's Consolidated Statements of Financial Position that relate to its variable interests under long-term purchase and sale contracts are predominantly related to working capital accounts and generally represent the amounts owed by or to DTE Energy for the deliveries associated with the current billing cycle under the contracts. As of December 31, 2019 , the carrying amount of assets and liabilities in DTE Electric's Consolidated Statements of Financial Position that relate to its variable interests under long-term purchase contracts are predominantly related to working capital accounts and generally represent the amounts owed by DTE Electric for the deliveries associated with the current billing cycle under the contracts. The Registrants have not provided any significant form of financial support associated with these long-term contracts. There is no material potential exposure to loss as a result of DTE Energy's variable interests through these long-term purchase and sale contracts. In addition, there is no material potential exposure to loss as a result of DTE Electric's variable interests through these long-term purchase contracts. The maximum risk exposure for consolidated VIEs is reflected on the Registrants' Consolidated Statements of Financial Position and for DTE Energy, in Note 19 to the Consolidated Financial Statements, " Commitments and Contingencies ," related to the REF guarantees and indemnities. For non-consolidated VIEs, the maximum risk exposure of the Registrants is generally limited to their investment, notes receivable, future funding commitments, and amounts which DTE Energy has guaranteed. See Note 19 to the Consolidated Financial Statements, " Commitments and Contingencies ," for further discussion of the NEXUS guarantee arrangements.
Other Income	Other Income Other income for the Registrants is recognized for non-operating income such as equity earnings of equity method investees, allowance for equity funds used during construction, contract services, and gains (losses) from trading securities. DTE Energy's Power and Industrial Projects segment also recognizes Other income in connection with the sale of membership interests in reduced emissions fuel facilities to investors. In exchange for the cash received, the investors will receive a portion of the economic attributes of the facilities, including income tax attributes. The transactions are not treated as a sale of membership interests for financial reporting purposes. Other income related to fixed non-refundable cash payments received from investors for which the earnings process is not contingent upon production of refined coal is recognized on a straight-line basis over the non-cancelable contract term as the economic benefit from the ownership of the facility is transferred to investors. Other income related to cash payments that is contingent upon production of refined coal is considered earned and recognized when the contingency regarding the timing and amount of payment is resolved, generally as refined coal is produced and tax credits are generated.
Accounting for ISO Transactions	Accounting for ISO Transactions DTE Electric participates in the energy market through MISO. MISO requires that DTE Electric submit hourly day-ahead, real-time, and FTR bids and offers for energy at locations across the MISO region. DTE Electric accounts for MISO transactions on a net hourly basis in each of the day-ahead, real-time, and FTR markets. In any single hour, transactions in each of the MISO energy markets are netted based on MWh to determine if DTE Electric is in a net sale or purchase position. Net purchases are recorded in Fuel, purchased power, and gas — utility and net sales are recorded in Operating Revenues — Utility operations on the Registrants' Consolidated Statements of Operations. The Energy Trading segment participates in the energy markets through various ISOs and RTOs. These markets require that Energy Trading submits hourly day-ahead, real-time bids and offers for energy at locations across each region. Energy Trading submits bids in the annual and monthly auction revenue rights and FTR auctions to the RTOs. Energy Trading accounts for these transactions on a net hourly basis for the day-ahead, real-time, and FTR markets. These transactions are related to trading contracts which, if derivatives, are presented on a net basis in Operating Revenues — Non-utility operations, and if non-derivatives, the realized gains and losses for sales are recorded in Operating Revenues — Non-utility operations and purchases are recorded in Fuel, purchased power, and gas — non-utility in the DTE Energy Consolidated Statements of Operations. DTE Electric and Energy Trading record accruals for future net purchases adjustments based on historical experience and reconcile accruals to actual costs when invoices are received from MISO and other ISOs and RTOs.
Derivatives	Derivatives The Registrants recognize all derivatives at their fair value as Derivative assets or liabilities on their respective Consolidated Statements of Financial Position unless they qualify for certain scope exceptions, including the normal purchases and normal sales exception. Further, derivatives that qualify and are designated for hedge accounting are classified as either hedges of a forecasted transaction or the variability of cash flows to be received or paid related to a recognized asset or liability (cash flow hedge); or as hedges of the fair value of a recognized asset or liability or of an unrecognized firm commitment (fair value hedge). For cash flow hedges, the derivative gain or loss is deferred in Accumulated other comprehensive income (loss) and later reclassified into earnings when the underlying transaction occurs. For fair value hedges, changes in fair values for the derivative and hedged item are recognized in earnings each period. For derivatives that do not qualify or are not designated for hedge accounting, changes in fair value are recognized in earnings each period. The Registrants' primary market risk exposure is associated with commodity prices, credit, and interest rates. The Registrants have risk management policies to monitor and manage market risks. The Registrants use derivative instruments to manage some of the exposure. DTE Energy uses derivative instruments for trading purposes in its Energy Trading segment. Contracts classified as derivative instruments include electricity, natural gas, oil, certain environmental contracts, forwards, futures, options, swaps, and foreign currency exchange contracts. Items not classified as derivatives include natural gas and environmental inventory, pipeline transportation contracts, some environmental contracts, and natural gas storage assets. DTE Electric — DTE Electric generates, purchases, distributes, and sells electricity. DTE Electric uses forward contracts to manage changes in the price of electricity and fuel. Substantially all of these contracts meet the normal purchases and normal sales exception and are therefore accounted for under the accrual method. Other derivative contracts are MTM and recoverable through the PSCR mechanism when settled. This results in the deferral of unrealized gains and losses as Regulatory assets or liabilities until realized. DTE Gas — DTE Gas purchases, stores, transports, distributes, and sells natural gas, buys and sells transportation capacity, and sells storage capacity. DTE Gas has fixed-priced contracts for portions of its expected natural gas supply requirements through March 2022. Substantially all of these contracts meet the normal purchases and normal sales exception and are therefore accounted for under the accrual method. DTE Gas may also sell forward transportation and storage capacity contracts. Forward transportation and storage contracts are generally not derivatives and are therefore accounted for under the accrual method. Gas Storage and Pipelines — This segment is primarily engaged in services related to the gathering, transportation, and storage of natural gas. Primarily fixed-priced contracts are used in the marketing and management of transportation and storage services. Generally, these contracts are not derivatives and are therefore accounted for under the accrual method. Power and Industrial Projects — This segment manages and operates energy and pulverized coal projects, a coke battery, reduced emissions fuel projects, renewable gas recovery, and power generation assets. Primarily fixed-price contracts are used in the marketing and management of the segment assets. These contracts are generally not derivatives and are therefore accounted for under the accrual method. Energy Trading — Commodity Price Risk — Energy Trading markets and trades electricity, natural gas physical products, and energy financial instruments, and provides energy and asset management services utilizing energy commodity derivative instruments. Forwards, futures, options, and swap agreements are used to manage exposure to the risk of market price and volume fluctuations in its operations. These derivatives are accounted for by recording changes in fair value to earnings unless hedge accounting criteria are met. Energy Trading — Foreign Currency Exchange Risk — Energy Trading has foreign currency exchange forward contracts to economically hedge fixed Canadian dollar commitments existing under natural gas and power purchase and sale contracts and natural gas transportation contracts. Energy Trading enters into these contracts to mitigate price volatility with respect to fluctuations of the Canadian dollar relative to the U.S. dollar. These derivatives are accounted for by recording changes in fair value to earnings unless hedge accounting criteria are met. Corporate and Other — Interest Rate Risk — DTE Energy may use interest rate swaps, treasury locks, and other derivatives to hedge the risk associated with interest rate market volatility. Credit Risk — DTE Energy maintains credit policies that significantly minimize overall credit risk. These policies include an evaluation of potential customers’ and counterparties’ financial condition, including the viability of underlying productive assets, credit rating, collateral requirements, or other credit enhancements such as letters of credit or guarantees. DTE Energy generally uses standardized agreements that allow the netting of positive and negative transactions associated with a single counterparty. DTE Energy maintains a provision for credit losses based on factors surrounding the credit risk of its customers, historical trends, and other information. Based on DTE Energy's credit policies and its December 31, 2019 provision for credit losses, DTE Energy’s exposure to counterparty nonperformance is not expected to have a material adverse effect on DTE Energy's Consolidated Financial Statements.
Changes in Accumulated Other Comprehensive Income (Loss)	Changes in Accumulated Other Comprehensive Income (Loss) Comprehensive income (loss) is the change in common shareholders’ equity during a period from transactions and events from non-owner sources, including Net Income. The amounts recorded to Accumulated other comprehensive income (loss) for DTE Energy include changes in benefit obligations, consisting of deferred actuarial losses and prior service costs, unrealized gains and losses from derivatives accounted for as cash flow hedges, DTE Energy's interest in other comprehensive income of equity investees which comprise the net unrealized gains and losses on investments, and foreign currency translation adjustments. DTE Energy releases income tax effects from accumulated other comprehensive income when the circumstances upon which they are premised cease to exist.
Cash, Cash Equivalents, and Restricted Cash	Cash, Cash Equivalents, and Restricted Cash Cash and cash equivalents include cash on hand, cash in banks, and temporary investments purchased with remaining maturities of three months or less. Restricted cash consists of funds held to satisfy requirements of certain debt and DTE Energy partnership operating agreements. Restricted cash designated for interest and principal payments within one year is classified as a Current Asset.
Receivables and Notes Receivable	Receivables Accounts receivable are primarily composed of trade receivables and unbilled revenue. The Registrants' Accounts receivable are stated at net realizable value. The allowance for doubtful accounts for DTE Electric and DTE Gas is generally calculated using the aging approach that utilizes rates developed in reserve studies. DTE Electric and DTE Gas establish an allowance for uncollectible accounts based on historical losses and management’s assessment of existing economic conditions, customer trends, and other factors. Customer accounts are generally considered delinquent if the amount billed is not received by the due date, which is typically in 21 days, however, factors such as assistance programs may delay aggressive action. DTE Electric and DTE Gas assess late payment fees on trade receivables based on past-due terms with customers. Customer accounts are written off when collection efforts have been exhausted. The time period for write-off is 150 days after service has been terminated. The customer allowance for doubtful accounts for DTE Energy's other businesses is calculated based on specific review of probable future collections based on receivable balances generally in excess of 30 days. DTE Energy unbilled revenues of $0.9 billion and $1.0 billion at December 31, 2019 and 2018 , respectively, include $263 million and $264 million of DTE Electric unbilled revenues, respectively, included in Customer Accounts receivable. Notes Receivable Notes receivable, or financing receivables, for DTE Energy are primarily comprised of finance lease receivables and loans and are included in Notes receivable and Other current assets on DTE Energy’s Consolidated Statements of Financial Position. Notes receivable, or financing receivables, for DTE Electric are primarily comprised of loans. Notes receivable are typically considered delinquent when payment is not received for periods ranging from 60 to 120 days. The Registrants cease accruing interest (nonaccrual status), consider a note receivable impaired, and establish an allowance for credit loss when it is probable that all principal and interest amounts due will not be collected in accordance with the contractual terms of the note receivable. Cash payments received on nonaccrual status notes receivable, that do not bring the account contractually current, are first applied to contractually owed past due interest, with any remainder applied to principal. Accrual of interest is generally resumed when the note receivable becomes contractually current. In determining the allowance for credit losses for notes receivable, the Registrants consider the historical payment experience and other factors that are expected to have a specific impact on the counterparty’s ability to pay. In addition, the Registrants monitor the credit ratings of the counterparties from which they have notes receivable.
Inventories	Inventories Inventory related to utility operations is generally valued at average cost. Inventory related to non-utility operations is valued at the lower of cost or net realizable value.
Property, Retirement and Maintenance, and Depreciation and Amortization	Property, Retirement and Maintenance, and Depreciation and Amortization Property is stated at cost and includes construction-related labor, materials, overheads, and AFUDC for utility property. The cost of utility properties retired is charged to accumulated depreciation. Expenditures for maintenance and repairs are charged to expense when incurred. Utility property at DTE Electric and DTE Gas is depreciated over its estimated useful life using straight-line rates approved by the MPSC. DTE Energy's non-utility property is depreciated over its estimated useful life using the straight-line method. Depreciation and amortization expense also includes the amortization of certain regulatory assets for the Registrants. The cost of nuclear fuel is capitalized. The amortization of nuclear fuel is included within Fuel, purchased power, and gas — utility in the DTE Energy Consolidated Statements of Operations, and Fuel and purchased power in the DTE Electric Consolidated Statements of Operations, and is recorded using the units-of-production method. Capitalized software costs are classified as Property, plant, and equipment and the related amortization is included in accumulated depreciation and amortization on the Registrants' Consolidated Financial Statements. The Registrants capitalize the costs associated with computer software developed or obtained for use in their businesses. The Registrants amortize capitalized software costs on a straight-line basis over the expected period of benefit, ranging from 3 to 15 years for DTE Energy and 3 to 15 years for DTE Electric.
Long-Lived Assets	Long-Lived Assets Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate the carrying amount of an asset may not be recoverable. If the carrying amount of the asset exceeds the expected undiscounted future cash flows generated by the asset, an impairment loss is recognized resulting in the asset being written down to its estimated fair value. Assets to be disposed of are reported at the lower of the carrying amount or fair value, less costs to sell.
Intangible Assets	DTE Energy amortizes customer relationship and contract intangible assets on a straight-line basis over the expected period of benefit.
Excise and Sales Taxes and Income Taxes	Excise and Sales Taxes The Registrants record the billing of excise and sales taxes as a receivable with an offsetting payable to the applicable taxing authority, with no net impact on the Registrants’ Consolidated Statements of Operations. Deferred tax assets and liabilities are recognized for the estimated future tax effect of temporary differences between the tax basis of assets or liabilities and the reported amounts in the Registrant's Consolidated Financial Statements. Consistent with the original establishment of these deferred tax liabilities (assets), recognition of these non-cash transactions are not reflected in the Consolidated Statements of Cash Flows. The federal income tax provisions or benefits of DTE Energy’s subsidiaries are determined on an individual company basis and recognize the tax benefit of tax credits and net operating losses, if applicable. The state and local income tax provisions of the utility subsidiaries are determined on an individual company basis and recognize the tax benefit of various tax credits and net operating losses, if applicable. The subsidiaries record federal, state, and local income taxes payable to or receivable from DTE Energy based on the federal, state, and local tax provisions of each company.
Deferred Debt Costs	Deferred Debt Costs The costs related to the issuance of long-term debt are deferred and amortized over the life of each debt issue. The deferred amounts are included as a direct deduction from the carrying amount of each debt issue in Mortgage bonds, notes, and other and Junior subordinated debentures on DTE Energy's Consolidated Statements of Financial Position and in Mortgage bonds, notes, and other on DTE Electric's Consolidated Statements of Financial Position. In accordance with MPSC regulations applicable to DTE Energy’s electric and gas utilities, the unamortized discount, premium, and expense related to utility debt redeemed with a refinancing are amortized over the life of the replacement issue. Discount, premium, and expense on early redemptions of debt associated with DTE Energy's non-utility operations are charged to earnings.
Investments in Debt and Equity Securities	Investments in Debt and Equity Securities
DTE Energy Foundation	DTE Energy Foundation There were no contributions made by DTE Energy to the DTE Energy Foundation for the year ended December 31, 2019 . DTE Energy's charitable contributions to the DTE Energy Foundation were $22 million and $43 million for the years ended December 31, 2018 and 2017 , respectively. The DTE Energy Foundation is a non-consolidated not-for-profit private foundation, the purpose of which is to contribute to and assist charitable organizations.
New Accounting Pronouncements	NEW ACCOUNTING PRONOUNCEMENTS Recently Adopted Pronouncements In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), as amended. This guidance requires a lessee to account for leases as finance or operating leases and disclose key information about leasing arrangements. Both types of leases will result in the lessee recognizing a right-of-use asset and a corresponding lease liability on its balance sheet, with differing methodology for income statement recognition, depending on the lease classification. The Registrants adopted the standard on January 1, 2019 using the prospective approach. The standard provides a number of transition practical expedients of which the Registrants elected the package of three expedients that must be taken together, allowing entities to not reassess whether an agreement is a lease, to carryforward the existing lease classification, and to not reassess initial direct costs associated with existing leases; but did not elect to apply hindsight in determining lease term and impairment of the right-to-use assets. The Registrants also elected to not evaluate land easements under the new guidance at adoption if they were not previously accounted for as leases. These practical expedients apply to leases that commenced prior to January 1, 2019. At adoption of the new standard, the Registrants recognized on the Consolidated Statements of Financial Position, right-of-use assets and lease liabilities for certain operating leases of approximately $137 million and $130 million , respectively, for DTE Energy and approximately $74 million and $67 million , respectively, for DTE Electric as of January 1, 2019. The right-of-use lease assets include $9 million of prepaid lease costs that have been reclassified from Other assets, current and noncurrent, and $2 million of deferred lease costs that have been reclassified from Other liabilities, current and noncurrent, for the Registrants. The adoption of the ASU did not have a significant impact on the Registrants' Consolidated Statements of Operations but required additional disclosures for leases. See Note 18 to the Consolidated Financial Statements, " Leases ." In February 2018, the FASB issued ASU No. 2018-02, Income Statement — Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income . The amendments in this update allow a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the TCJA. The amendments in this update also require entities to disclose their accounting policy for releasing income tax effects from accumulated other comprehensive income. The Registrants adopted the standard effective January 1, 2019. Upon adoption, DTE Energy reclassified $25 million of income tax effects from Accumulated other comprehensive income (loss) to Retained Earnings. Recently Issued Pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments — Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, as amended. The amendments in this update replace the incurred loss impairment methodology in current generally accepted accounting principles with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information, including forecasts, to develop credit loss estimates. The ASU requires entities to use the new methodology to measure impairment of financial instruments, including accounts receivable, and may result in earlier recognition of credit losses than under current generally accepted accounting principles. Entities will apply the new guidance as a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is adopted. The ASU is effective for the Registrants beginning after December 15, 2019, and interim periods therein. The Registrants will adopt the ASU on its effective date. The Registrants are currently assessing the impact of this standard on their Consolidated Financial Statements. In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurements (Topic 820): Disclosure Framework — Changes to the Disclosure Requirements for Fair Value Measurement . The amendments in this update modify the disclosure requirements on fair value measurements in Topic 820. The ASU is effective for the Registrants for fiscal years beginning after December 15, 2019, and interim periods therein. The Registrants will adopt the ASU on its effective date. The Registrants are currently assessing the impact of this standard on their Consolidated Financial Statements. In August 2018, the FASB issued ASU No. 2018-14, Compensation — Retirement Benefits — Defined Benefit Plans (Subtopic 715-20): Disclosure Framework — Changes to the Disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans . The amendments in this update modify the disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans. The ASU is effective for the Registrants for fiscal years ending after December 15, 2020. Early adoption is permitted. The Registrants anticipate adopting the ASU on its effective date. The Registrants are currently assessing the impact of this standard on their Consolidated Financial Statements. In August 2018, the FASB issued ASU No. 2018-15, Intangibles — Goodwill and Other — Internal-Use Software (Subtopic 350-40): Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That is a Service Contract . The amendments in this update align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal use software license). The ASU is effective for the Registrants for fiscal years beginning after December 15, 2019, and interim periods therein. The Registrants will adopt the ASU on its effective date. The ASU may be applied using either a retrospective or prospective approach. The Registrants will apply the ASU prospectively, and are currently assessing the impact of this standard on their Consolidated Financial Statements. In October 2018, the FASB issued ASU No. 2018-17, Consolidation (Topic 810): Targeted Improvements to Related Party Guidance for Variable Interest Entities . The amendments in this update modify the requirements for determining whether a decision-making fee is a variable interest and require reporting entities to consider indirect interests held through related parties under common control on a proportional basis. The ASU is effective for the Registrants for fiscal years beginning after December 15, 2019, and interim periods therein. The Registrants will adopt the ASU on its effective date. The Registrants are currently assessing the impact of this standard on their Consolidated Financial Statements. In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740) — Simplifying the Accounting for Income Taxes . The amendments in this update simplify the accounting for income taxes by removing certain exceptions and clarifying certain requirements regarding franchise taxes, goodwill, consolidated tax expenses, and annual effective tax rate calculations. The ASU is effective for the Registrants for fiscal years beginning after December 15, 2020. Early adoption is permitted. The Registrants are currently assessing the impact of this standard on their Consolidated Financial Statements.
Revenues	Upon the adoption of Topic 606, revenue is measured based upon the consideration specified in a contract with a customer at the time when performance obligations are satisfied. Under Topic 606, a performance obligation is a promise in a contract to transfer a distinct good or service or a series of distinct goods or services to the customer. The Registrants recognize revenue when performance obligations are satisfied by transferring control over a product or service to a customer. The Registrants have determined control to be transferred when the product is delivered or the service is provided to the customer. For the years ended December 31, 2019 and 2018 , recognition of revenue for the Registrants subsequent to the adoption of Topic 606 is substantially similar in amount and approach to that prior to adoption. Rates for DTE Electric and DTE Gas include provisions to adjust billings for fluctuations in fuel and purchased power costs, cost of natural gas, and certain other costs. Revenues are adjusted for differences between actual costs subject to reconciliation and the amounts billed in current rates. Under or over recovered revenues related to these cost recovery mechanisms are included in Regulatory assets or liabilities on the Registrants' Consolidated Statements of Financial Position and are recovered or returned to customers through adjustments to the billing factors.
Asset Retirement Obligations	ASSET RETIREMENT OBLIGATIONS DTE Electric has a legal retirement obligation for the decommissioning costs for its Fermi 1 and Fermi 2 nuclear plants, dismantlement of facilities located on leased property, and various other operations. DTE Electric has conditional retirement obligations for asbestos and PCB removal at certain of its power plants and various distribution equipment. DTE Gas has conditional retirement obligations for gas pipelines, certain service centers, compressor and gate stations. The Registrants recognize such obligations as liabilities at fair market value when they are incurred, which generally is at the time the associated assets are placed in service. Fair value is measured using expected future cash outflows discounted at the Registrants' credit-adjusted risk-free rate. For its utility operations, the Registrants recognize in the Consolidated Statements of Operations removal costs in accordance with regulatory treatment. Any differences between costs recognized related to asset retirement and those reflected in rates are recognized as either a Regulatory asset or liability on the Consolidated Statements of Financial Position. If a reasonable estimate of fair value cannot be made in the period in which the retirement obligation is incurred, such as for assets with indeterminate lives, the liability is recognized when a reasonable estimate of fair value can be made. Natural gas storage system and certain other distribution assets for DTE Gas and substations, manholes, and certain other distribution assets for DTE Electric have an indeterminate life. Therefore, no liability has been recorded for these assets.
Regulatory Assets and Liabilities	Regulatory Assets and Liabilities DTE Electric and DTE Gas are required to record Regulatory assets and liabilities for certain transactions that would have been treated as revenue or expense in non-regulated businesses. Continued applicability of regulatory accounting treatment requires that rates be designed to recover specific costs of providing regulated services and be charged to and collected from customers. Future regulatory changes could result in the discontinuance of this accounting treatment for Regulatory assets and liabilities for some or all of the Registrants' businesses and may require the write-off of the portion of any Regulatory asset or liability that was no longer probable of recovery through regulated rates. Management believes that currently available facts support the continued use of Regulatory assets and liabilities and that all Regulatory assets and liabilities are recoverable or refundable in the current regulatory environment.
Fair Value Measurement	Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date in a principal or most advantageous market. Fair value is a market-based measurement that is determined based on inputs, which refer broadly to assumptions that market participants use in pricing assets or liabilities. These inputs can be readily observable, market corroborated, or generally unobservable inputs. The Registrants make certain assumptions they believe that market participants would use in pricing assets or liabilities, including assumptions about risk, and the risks inherent in the inputs to valuation techniques. Credit risk of the Registrants and their counterparties is incorporated in the valuation of assets and liabilities through the use of credit reserves, the impact of which was immaterial at December 31, 2019 and 2018 . The Registrants believe they use valuation techniques that maximize the use of observable market-based inputs and minimize the use of unobservable inputs. A fair value hierarchy has been established that prioritizes the inputs to valuation techniques used to measure fair value in three broad levels. The fair value hierarchy gives the highest priority to quoted prices (unadjusted) in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3). In some cases, the inputs used to measure fair value might fall in different levels of the fair value hierarchy. All assets and liabilities are required to be classified in their entirety based on the lowest level of input that is significant to the fair value measurement in its entirety. Assessing the significance of a particular input may require judgment considering factors specific to the asset or liability and may affect the valuation of the asset or liability and its placement within the fair value hierarchy. The Registrants classify fair value balances based on the fair value hierarchy defined as follows: • Level 1 — Consists of unadjusted quoted prices in active markets for identical assets or liabilities that the Registrants have the ability to access as of the reporting date. • Level 2 — Consists of inputs other than quoted prices included within Level 1 that are directly observable for the asset or liability or indirectly observable through corroboration with observable market data. • Level 3 — Consists of unobservable inputs for assets or liabilities whose fair value is estimated based on internally developed models or methodologies using inputs that are generally less readily observable and supported by little, if any, market activity at the measurement date. Unobservable inputs are developed based on the best available information and subject to cost-benefit constraints.
Nuclear Decommissioning Trusts and Other Investments	Nuclear Decommissioning Trusts and Other Investments The nuclear decommissioning trusts and other investments hold debt and equity securities directly and indirectly through commingled funds. Exchange-traded debt and equity securities held directly are valued using quoted market prices in actively traded markets. Commingled funds that hold exchange-traded equity or debt securities are valued based on stated NAVs. Non-exchange traded fixed income securities are valued based upon quotations available from brokers or pricing services. Other assets such as private equity investments are classified as NAV assets. A primary price source is identified by asset type, class, or issue for each security. The trustee monitors prices supplied by pricing services and may use a supplemental price source or change the primary price source of a given security if the trustee determines that another price source is considered preferable. The Registrants have obtained an understanding of how these prices are derived, including the nature and observability of the inputs used in deriving such prices.
Derivative Assets and Liabilities	Derivative Assets and Liabilities Derivative assets and liabilities are comprised of physical and financial derivative contracts, including futures, forwards, options, and swaps that are both exchange-traded and over-the-counter traded contracts. Various inputs are used to value derivatives depending on the type of contract and availability of market data. Exchange-traded derivative contracts are valued using quoted prices in active markets. The Registrants consider the following criteria in determining whether a market is considered active: frequency in which pricing information is updated, variability in pricing between sources or over time, and the availability of public information. Other derivative contracts are valued based upon a variety of inputs including commodity market prices, broker quotes, interest rates, credit ratings, default rates, market-based seasonality, and basis differential factors. The Registrants monitor the prices that are supplied by brokers and pricing services and may use a supplemental price source or change the primary price source of an index if prices become unavailable or another price source is determined to be more representative of fair value. The Registrants have obtained an understanding of how these prices are derived. Additionally, the Registrants selectively corroborate the fair value of their transactions by comparison of market-based price sources. Mathematical valuation models are used for derivatives for which external market data is not readily observable, such as contracts which extend beyond the actively traded reporting period. The Registrants have established a Risk Management Committee whose responsibilities include directly or indirectly ensuring all valuation methods are applied in accordance with predefined policies. The development and maintenance of the Registrants' forward price curves has been assigned to DTE Energy's Risk Management Department, which is separate and distinct from the trading functions within DTE Energy.
Fair Value Transfer	Derivatives are transferred between levels primarily due to changes in the source data used to construct price curves as a result of changes in market liquidity. Transfers in and transfers out are reflected as if they had occurred at the beginning of the period.
Derivatives, Offsetting Fair Value Amounts	Certain of DTE Energy's derivative positions are subject to netting arrangements which provide for offsetting of asset and liability positions as well as related cash collateral. Such netting arrangements generally do not have restrictions. Under such netting arrangements, DTE Energy offsets the fair value of derivative instruments with cash collateral received or paid for those contracts executed with the same counterparty, which reduces DTE Energy's Total Assets and Liabilities. Cash collateral is allocated between the fair value of derivative instruments and customer accounts receivable and payable with the same counterparty on a pro-rata basis to the extent there is exposure. Any cash collateral remaining, after the exposure is netted to zero, is reflected in Accounts receivable and Accounts payable as collateral paid or received, respectively. DTE Energy also provides and receives collateral in the form of letters of credit which can be offset against net Derivative assets and liabilities as well as Accounts receivable and payable. DTE Energy had issued letters of credit of $6 million outstanding at December 31, 2019 and $4 million at December 31, 2018 , which could be used to offset net Derivative liabilities. Letters of credit received from third parties which could be used to offset net Derivative assets were $4 million and $8 million at December 31, 2019 and 2018 , respectively. Such balances of letters of credit are excluded from the tables below and are not netted with the recognized assets and liabilities in DTE Energy's Consolidated Statements of Financial Position. For contracts with certain clearing agents, the fair value of derivative instruments is netted against realized positions with the net balance reflected as either 1) a Derivative asset or liability or 2) an Account receivable or payable. Other than certain clearing agents, Accounts receivable and Accounts payable that are subject to netting arrangements have not been offset against the fair value of Derivative assets and liabilities.
Derivatives, Methods of Accounting	Revenues and energy costs related to trading contracts are presented on a net basis in DTE Energy's Consolidated Statements of Operations. Commodity derivatives used for trading purposes, and financial non-trading commodity derivatives, are accounted for using the MTM method with unrealized and realized gains and losses recorded in Operating Revenues — Non-utility operations. Non-trading physical commodity sale and purchase derivative contracts are generally accounted for using the MTM method with unrealized and realized gains and losses for sales recorded in Operating Revenues — Non-utility operations and purchases recorded in Fuel, purchased power, and gas — non-utility.
Lessee	Lessee Topic 842 — Leases at DTE Energy are primarily comprised of various forms of equipment, computer hardware, coal railcars, production facilities, buildings, and certain easement leases with terms ranging from approximately 2 to 40 years. Leases at DTE Electric are primarily comprised of various forms of equipment, computer hardware, coal railcars, and certain easement leases with terms ranging from approximately 2 to 40 years. A lease is deemed to exist when the Registrants have the right to control the use of identified property, plant or equipment, as conveyed through a contract, for a certain period of time and consideration paid. The right to control is deemed to occur when the Registrants have the right to obtain substantially all of the economic benefits of the identified assets and the right to direct the use of such assets. Lease liabilities are determined utilizing a discount rate to determine the present values of lease payments. Topic 842 requires the use of the rate implicit in the lease when it is readily determinable. When the rate implicit in the lease is not readily determinable, the incremental borrowing rate is used. The Registrants have determined their respective incremental borrowing rates based upon the rate of interest that would have been paid on a collateralized basis over similar tenors to that of the leases. The incremental borrowing rates for DTE Electric and DTE Gas have been determined utilizing respective secured borrowing rates for first mortgage bonds with like tenors of remaining lease terms. Incremental borrowing rates for non-utility entities have been determined utilizing an implied secured borrowing rate based upon an unsecured rate for a similar tenor of remaining lease terms, which is then adjusted for the estimated impact of collateral. Certain leases of the Registrants contain escalation clauses whereby the payments are adjusted for consumer price or labor indices. DTE Energy has leases with non-index based escalation clauses for fixed dollar or percentage increases. DTE Electric has leases with non-index based escalation clauses for fixed dollar increases. DTE Energy also has leases with variable payments based upon usage of, or revenues associated with, the leased assets. DTE Electric also has leases with variable payments based upon the usage of the leased assets. Certain leases of easements and coal railcars contain provisions whereby the Registrants have the option to terminate the lease agreement by giving notice of such termination during the time frames specified in the respective lease. The Registrants have considered such provisions in the determination of the lease term when it is reasonably certain that the lease would be terminated. The Registrants have certain leases which contain purchase options. Based upon the nature of the leased property and terms of the purchase options, the Registrants have determined it is not reasonably certain that such purchase options will be utilized. Thus, the impact of the purchase options has not been included in the determination of right-of-use assets and lease liabilities for the subject leases. The Registrants have certain leases which contain renewal options. Where the renewal options were deemed reasonably certain to occur, the impacts of such options were included in the determination of the right of use assets and lease liabilities. The Registrants have agreements with lease and non-lease components, which are generally accounted for separately. Consideration in a lease is allocated between lease and non-lease components based upon the estimated relative standalone prices. The Registrants have certain coal railcar leases for which non-lease and lease components are accounted for as a single lease component, as permitted under Topic 842.
Lessor	Topic 842 — DTE Energy leases a portion of its pipeline system to the Vector Pipeline through a finance lease contract that has been renewed through 2025, with additional renewal options reasonably certain to be exercised through 2040. DTE Energy owns a 40% interest in the Vector Pipeline. In addition, DTE Energy has an energy services agreement that expires in 2026, of which a portion is accounted for as a finance lease. DTE Energy also leases various assets under operating leases for a pipeline, energy facilities and related equipment. Such leases are comprised of both fixed payments and variable payments which are contingent on volumes, with terms ranging from 3 to 24 years. Generally, the operating leases do not have renewal provisions or options to purchase the assets at the end of the lease. The operating leases generally do not have termination for convenience provisions. Termination may be allowed under specific circumstances stated in the lease contract, such as under an event of default. Certain of the finance and operating leases have lease terms that extend to the end of the estimated economic life of the leased assets, thereby resulting in no residual value. Any remaining residual values under the finance and operating leases are expected to be recovered through rates, renewals or new lease contracts. Residual values have been determined using the estimated economic life of the leased assets. The finance and operating leases do not contain residual value guarantees. Certain of the operating leases have both lease and non-lease components. The lease and non-lease components are allocated based upon estimated relative standalone selling prices. A lease is deemed to exist when the Registrants have provided other parties with the right to control the use of identified property, plant or equipment, as conveyed through a contract, for a certain period of time and consideration received. The right to control is deemed to occur when the Registrants have provided other parties with the right to obtain substantially all of the economic benefits of the identified assets and the right to direct the use of such assets.
Stock-Based Compensation	DTE Energy records compensation expense at fair value over the vesting period for all awards it grants.

Organization and Basis of Pre_2

Organization and Basis of Presentation (Tables)	12 Months Ended
	Dec. 31, 2019
Variable Interest Entity, Consolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Schedule of Variable Interest Entities	The following table summarizes the major Consolidated Statements of Financial Position items for consolidated VIEs as of December 31, 2019 and 2018 . All assets and liabilities of a consolidated VIE are presented where it has been determined that a consolidated VIE has either (1) assets that can be used only to settle obligations of the VIE or (2) liabilities for which creditors do not have recourse to the general credit of the primary beneficiary. VIEs, in which DTE Energy holds a majority voting interest and is the primary beneficiary, that meet the definition of a business and whose assets can be used for purposes other than the settlement of the VIE's obligations have been excluded from the table below. Amounts for DTE Energy's consolidated VIEs are as follows: December 31, 2019 December 31, 2018 SGG (a) Other Total SGG (a) Other Total (In millions) ASSETS Cash and cash equivalents $ 16 $ 11 $ 27 $ 25 $ 14 $ 39 Restricted cash — — — — 5 5 Accounts receivable 8 19 27 9 37 46 Inventories — 74 74 1 92 93 Property, plant, and equipment, net 410 33 443 395 46 441 Goodwill 25 — 25 25 — 25 Intangible assets 542 — 542 557 — 557 Other current and long-term assets 2 — 2 3 — 3 $ 1,003 $ 137 $ 1,140 $ 1,015 $ 194 $ 1,209 LIABILITIES Accounts payable and accrued current liabilities $ 2 $ 13 $ 15 $ 3 $ 31 $ 34 Other current and long-term liabilities 7 7 14 9 10 19 $ 9 $ 20 $ 29 $ 12 $ 41 $ 53 _____________________________________ (a) Amounts shown are 100% of SGG's assets and liabilities, of which DTE Energy owns 85% at December 31, 2019 and 55% at December 31, 2018.
Summary of Amounts For Nonconsolidated Variable Interest Entities	Amounts for DTE Energy's non-consolidated VIEs are as follows: December 31, 2019 2018 (In millions) Investments in equity method investees $ 1,503 $ 1,425 Notes receivable $ 21 $ 15 Future funding commitments $ 63 $ 55
Equity Method Investments	DTE Energy equity method investees are described below: Investments % Owned Segment 2019 2018 2019 2018 Description (In millions) Significant Equity Method Investees Gas Storage and Pipelines NEXUS Pipeline $ 1,345 $ 1,260 50% 50% 256-mile pipeline to transport Utica and Marcellus shale gas to Ohio, Michigan, and Ontario market centers. Also includes Generation Pipeline, a 23-mile pipeline located in northern Ohio Vector Pipeline 131 123 40% 40% 348-mile pipeline connecting Chicago, Michigan, and Ontario market centers Millennium Pipeline 209 202 26% 26% 263-mile pipeline serving markets in the Northeast 1,685 1,585 Other Equity Method Investees Other Segments 177 186 $ 1,862 $ 1,771 Summarized balance sheet data is as follows: December 31, 2019 2018 (In millions) Current Assets $ 374 $ 358 Non-current assets $ 5,260 $ 5,101 Current Liabilities $ 414 $ 391 Non-current liabilities $ 698 $ 762 Summarized income statement data is as follows: December 31, 2019 2018 2017 (In millions) Operating Revenues $ 1,210 $ 883 $ 756 Operating Expenses $ 853 $ 622 $ 561 Net Income $ 313 $ 365 $ 254

Significant Accounting Polici_3

Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Schedule of Other Income	The following is a summary of DTE Energy's Other income: 2019 2018 2017 (In millions) Income from REF entities $ 130 $ 98 $ 77 Equity earnings of equity method investees 111 132 102 Gains from equity securities 37 6 26 Contract services 29 51 19 Allowance for equity funds used during construction 24 28 23 Other 19 18 21 $ 350 $ 333 $ 268 The following is a summary of DTE Electric's Other income: 2019 2018 2017 (In millions) Gains from equity securities allocated from DTE Energy $ 37 $ 6 $ 26 Contract services 32 51 21 Allowance for equity funds used during construction 22 19 18 Other 16 7 12 $ 107 $ 83 $ 77
Schedule of Accumulated Other Comprehensive Income (Loss)	The following table summarizes the changes in DTE Energy's Accumulated other comprehensive income (loss) by component (a) for the years ended December 31, 2019 and 2018 : Net Unrealized Gain (Loss) on Derivatives Net Unrealized Loss on Investments Benefit Obligations (b) Foreign Currency Translation Total (In millions) Balance, December 31, 2017 $ (3 ) $ (2 ) $ (110 ) $ (5 ) $ (120 ) Other comprehensive loss before reclassifications (2 ) — (1 ) (2 ) (5 ) Amounts reclassified from Accumulated other comprehensive income (loss) 1 — 9 — 10 Net current-period Other comprehensive income (loss) (1 ) — 8 (2 ) 5 Implementation of ASU 2016-01 (7 ) 2 — — (5 ) Balance, December 31, 2018 $ (11 ) $ — $ (102 ) $ (7 ) $ (120 ) Other comprehensive income (loss) before reclassifications (14 ) — (7 ) 1 (20 ) Amounts reclassified from Accumulated other comprehensive income (loss) 2 — 15 — 17 Net current-period Other comprehensive income (loss) (12 ) — 8 1 (3 ) Implementation of ASU 2018-02 (2 ) — (23 ) — (25 ) Balance, December 31, 2019 $ (25 ) $ — $ (117 ) $ (6 ) $ (148 ) ______________________________________ (a) All amounts are net of tax, except for Foreign currency translation. (b) The amounts reclassified from Accumulated other comprehensive income (loss) are included in the computation of the net periodic pension and other postretirement benefit costs (see Note 21 to the Consolidated Financial Statements, " Retirement Benefits and Trusteed Assets ").
Schedule of Finite-Lived Intangible Assets by Major Class	The Registrants have certain Intangible assets as shown below: December 31, 2019 December 31, 2018 Useful Lives Gross Carrying Value Accumulated Amortization Net Carrying Value Gross Carrying Value Accumulated Amortization Net Carrying Value (In millions) Intangible assets subject to amortization Customer relationships 25 to 40 years (a) $ 2,252 $ (66 ) $ 2,186 $ 779 $ (44 ) $ 735 Contract intangibles 6 to 26 years 268 (76 ) 192 159 (66 ) 93 2,520 (142 ) 2,378 938 (110 ) 828 DTE Electric renewable energy credits (b) 15 — 15 20 — 20 DTE Electric emission allowances (b) — — — 1 — 1 DTE Electric Long-term intangible assets 15 — 15 21 — 21 DTE Energy Long-term intangible assets $ 2,535 $ (142 ) $ 2,393 $ 959 $ (110 ) $ 849 ______________________________________ (a) The useful lives of the customer relationship intangible assets are based on the number of years in which the assets are expected to economically contribute to the business. The expected economic benefit incorporates existing customer contracts and expected renewal rates based on the estimated volume and production lives of gas resources in the region. (b) Emission allowances and renewable energy credits are charged to expense, using average cost, as the allowances and credits are consumed in the operation of the business.
Schedule of Indefinite-Lived Intangible Assets	The Registrants have certain Intangible assets as shown below: December 31, 2019 December 31, 2018 Useful Lives Gross Carrying Value Accumulated Amortization Net Carrying Value Gross Carrying Value Accumulated Amortization Net Carrying Value (In millions) Intangible assets subject to amortization Customer relationships 25 to 40 years (a) $ 2,252 $ (66 ) $ 2,186 $ 779 $ (44 ) $ 735 Contract intangibles 6 to 26 years 268 (76 ) 192 159 (66 ) 93 2,520 (142 ) 2,378 938 (110 ) 828 DTE Electric renewable energy credits (b) 15 — 15 20 — 20 DTE Electric emission allowances (b) — — — 1 — 1 DTE Electric Long-term intangible assets 15 — 15 21 — 21 DTE Energy Long-term intangible assets $ 2,535 $ (142 ) $ 2,393 $ 959 $ (110 ) $ 849 ______________________________________ (a) The useful lives of the customer relationship intangible assets are based on the number of years in which the assets are expected to economically contribute to the business. The expected economic benefit incorporates existing customer contracts and expected renewal rates based on the estimated volume and production lives of gas resources in the region. (b) Emission allowances and renewable energy credits are charged to expense, using average cost, as the allowances and credits are consumed in the operation of the business.
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	The following table summarizes DTE Energy's estimated customer relationship and contract intangible amortization expense expected to be recognized during each year through 2024 : 2020 2021 2022 2023 2024 (In millions) Estimated amortization expense $ 82 $ 86 $ 86 $ 86 $ 86
Schedule of Accounting Policies	See the following notes for other accounting policies impacting the Registrants’ Consolidated Financial Statements: Note Title 5 Revenue 9 Asset Retirement Obligations 10 Regulatory Matters 11 Income Taxes 13 Fair Value 14 Financial and Other Derivative Instruments 18 Leases 21 Retirement Benefits and Trusteed Assets 22 Stock-Based Compensation

Acquisitions (Tables)

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2019
Business Combinations [Abstract]
Schedule of Final Purchase Price Allocation	The acquisition was accounted for using the acquisition method of accounting for business combinations. Accordingly, the cost was allocated to the underlying net assets based on their respective fair values as shown below: (In millions) Contract intangibles $ 109 Property, plant, and equipment, net 60 Working capital 6 Total $ 175 (In millions) Assets Cash $ 62 Accounts receivable 31 Property, plant, and equipment, net 1,035 Goodwill 171 Customer relationship intangibles 1,473 Other current assets 1 $ 2,773 Liabilities Accounts payable $ 26 Acquisition related deferred payment 378 Other current liabilities 2 Asset retirement obligations 9 $ 415 Total cash consideration $ 2,358

Revenue (Tables)

Revenue (Tables)	12 Months Ended
	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following is a summary of revenues disaggregated by segment for DTE Energy: 2019 2018 (In millions) Electric (a) Residential $ 2,427 $ 2,494 Commercial 1,795 1,794 Industrial 659 690 Other (b) 348 320 Total Electric operating revenues (c) $ 5,229 $ 5,298 Gas Gas sales $ 1,043 $ 1,055 End User Transportation 219 232 Intermediate Transportation 78 58 Other (b) 142 91 Total Gas operating revenues (d) $ 1,482 $ 1,436 Other segment operating revenues Gas Storage and Pipelines (e) $ 501 $ 485 Power and Industrial Projects (f) $ 1,560 $ 2,204 Energy Trading (g) $ 4,610 $ 5,557 _______________________________________ (a) Revenues under the Electric segment generally represent those of DTE Electric. (b) Includes revenue adjustments related to various regulatory mechanisms. (c) Includes $22 million under Alternative Revenue Programs and $19 million of other revenues, which are both outside the scope of Topic 606 for the year ended December 31, 2019 and includes $21 million under Alternative Revenue Programs and $20 million of other revenues, which are both outside the scope of Topic 606 for the year ended December 31, 2018 . (d) Includes $8 million under Alternative Revenue Programs and $7 million of other revenues, which are both outside the scope of Topic 606 for the year ended December 31, 2019 and includes $2 million under Alternative Revenue Programs and $7 million of other revenues, which are both outside the scope of Topic 606 for the year ended December 31, 2018 . (e) Includes revenues outside the scope of Topic 606 primarily related to $9 million of contracts accounted for as leases for the year ended December 31, 2019 . (f) Includes revenues outside the scope of Topic 606 primarily related to $121 million and $125 million of contracts accounted for as leases for the years ended December 31, 2019 and December 31, 2018 , respectively. (g) Includes revenues outside the scope of Topic 606 primarily related to $3.4 billion and $4.5 billion of derivatives for the years ended December 31, 2019 and December 31, 2018 , respectively.
Summary of Deferred Revenue Activity	The following is a summary of deferred revenue activity: DTE Energy (In millions) Beginning Balance, January 1, 2019 $ 74 Increases due to cash received or receivable, excluding amounts recognized as revenue during the period 51 Revenue recognized that was included in the deferred revenue balance at the beginning of the period (50 ) Ending Balance, December 31, 2019 $ 75
Deferred Revenue Amounts Expected to be Recognized as Revenue in Future Periods	The following table represents deferred revenue amounts for DTE Energy that are expected to be recognized as revenue in future periods: DTE Energy (In millions) 2020 $ 43 2021 6 2022 7 2023 6 2024 3 2025 and thereafter 10 $ 75 The Registrants expect to recognize revenue for the following amounts related to fixed consideration associated with remaining performance obligations in each of the future periods noted: DTE Energy DTE Electric (In millions) 2020 $ 253 $ 8 2021 292 8 2022 232 7 2023 164 7 2024 126 7 2025 and thereafter 538 — $ 1,605 $ 37
Schedule of Expenses Recognized for Estimated Uncollectible Accounts Receivable	The following table represents expenses recognized for estimated uncollectible accounts receivable: December 31, 2019 2018 (In millions) DTE Energy $ 111 $ 140 DTE Electric $ 65 $ 85

Goodwill (Tables)

Goodwill (Tables)	12 Months Ended
	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	The following is the summary of change in the carrying amount of goodwill for the years ended December 31: 2019 2018 (In millions) Balance as of January 1 $ 2,293 $ 2,293 Goodwill attributable to Gas Storage and Pipelines 2019 acquisition of Blue Union and LEAP 171 — Balance at December 31 $ 2,464 $ 2,293

Property, Plant, and Equipment

Property, Plant, and Equipment (Tables)	12 Months Ended
	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
PP&E by Classification, Summary of Depreciation and Amortization	The following is a summary of Depreciation and amortization expense for DTE Energy: 2019 2018 2017 (In millions) Property, plant, and equipment $ 997 $ 878 $ 829 Regulatory assets and liabilities 227 212 165 Intangible assets 33 27 29 Other 6 7 7 $ 1,263 $ 1,124 $ 1,030 The following is a summary of Depreciation and amortization expense for DTE Electric: 2019 2018 2017 (In millions) Property, plant, and equipment $ 748 $ 652 $ 615 Regulatory assets and liabilities 193 179 133 Other 5 5 5 $ 946 $ 836 $ 753 The following is a summary of Property, plant, and equipment by classification as of December 31: 2019 2018 Property, plant, and equipment (In millions) DTE Electric Generation $ 12,028 $ 11,027 Distribution 9,715 9,153 Other 2,536 2,567 Total DTE Electric 24,279 22,747 DTE Gas Distribution 4,164 3,823 Storage 570 548 Transmission and other 1,244 1,204 Total DTE Gas 5,978 5,575 Non-utility and other Gas Storage and Pipelines 3,524 2,307 Power and Industrial Projects 1,108 1,070 Other 183 111 Non-utility and other 4,815 3,488 Total DTE Energy 35,072 31,810 Accumulated depreciation and amortization DTE Electric Generation (3,460 ) (3,609 ) Distribution (2,553 ) (2,974 ) Other (693 ) (727 ) Total DTE Electric (6,706 ) (7,310 ) DTE Gas Distribution (1,334 ) (1,283 ) Storage (172 ) (165 ) Transmission and other (409 ) (404 ) Total DTE Gas (1,915 ) (1,852 ) Non-utility and other Gas Storage and Pipelines (459 ) (390 ) Power and Industrial Projects (604 ) (546 ) Other (71 ) (62 ) Non-utility and other (1,134 ) (998 ) Total DTE Energy (9,755 ) (10,160 ) Net DTE Energy Property, plant, and equipment $ 25,317 $ 21,650 Net DTE Electric Property, plant, and equipment $ 17,573 $ 15,437 DTE Energy DTE Electric (In millions) Gross property under capital leases $ 18 $ 18 Accumulated amortization of property under capital leases $ 7 $ 7
Schedule of AFUDC and Interest Capitalized	The following is a summary of the Registrants' AFUDC and interest capitalized for the years ended December 31: DTE Energy DTE Electric 2019 2018 2019 2018 (In millions) Allowance for debt funds used during construction and interest capitalized $ 15 $ 15 $ 10 $ 9 Allowance for equity funds used during construction 24 28 22 19 Total $ 39 $ 43 $ 32 $ 28
Schedule of Utility Property, Plant, and Equipment	The average estimated useful life for each major class of utility Property, plant, and equipment as of December 31, 2019 follows: Estimated Useful Lives in Years Utility Generation Distribution Storage DTE Electric 34 38 N/A DTE Gas N/A 50 56
Schedule of Capitalized Software	The following balances for capitalized software relate to DTE Energy: Year Ended December 31, 2019 2018 2017 (In millions) Amortization expense of capitalized software $ 123 $ 108 $ 101 Gross carrying value of capitalized software $ 906 $ 905 Accumulated amortization of capitalized software $ 520 $ 534 The following balances for capitalized software relate to DTE Electric: Year Ended December 31, 2019 2018 2017 (In millions) Amortization expense of capitalized software $ 112 $ 101 $ 93 Gross carrying value of capitalized software $ 811 $ 799 Accumulated amortization of capitalized software $ 462 $ 463

Jointly-Owned Utility Plant (Ta

Jointly-Owned Utility Plant (Tables)	12 Months Ended
	Dec. 31, 2019
Jointly Owned Utility Plant, Net Ownership Amount [Abstract]
Schedule of Jointly-Owned Utility Plants	DTE Electric's ownership information of the two utility plants as of December 31, 2019 was as follows: Belle River Ludington In-service date 1984-1985 1973 Total plant capacity 1,270 MW 2,220 MW Ownership interest 81% 49% Investment in Property, plant, and equipment (in millions) $ 1,903 $ 616 Accumulated depreciation (in millions) $ 896 $ 193

Asset Retirement Obligations (T

Asset Retirement Obligations (Tables)	12 Months Ended
	Dec. 31, 2019
Asset Retirement Obligation Disclosure [Abstract]
Schedule of Change in Asset Retirement Obligations	Changes to asset retirement obligations for 2019 , 2018 , and 2017 were as follows: 2019 2018 2017 DTE Energy (In millions) Asset retirement obligations at January 1 $ 2,469 $ 2,320 $ 2,197 Accretion 149 140 131 Liabilities incurred 20 27 2 Liabilities settled (17 ) (16 ) (6 ) Revision in estimated cash flows 51 (2 ) (4 ) Asset retirement obligations at December 31 $ 2,672 $ 2,469 $ 2,320 2019 2018 2017 DTE Electric (In millions) Asset retirement obligations at January 1 $ 2,271 $ 2,125 $ 2,012 Accretion 138 129 120 Liabilities incurred 1 27 1 Liabilities settled (14 ) (8 ) (2 ) Revision in estimated cash flows 51 (2 ) (6 ) Asset retirement obligations at December 31 $ 2,447 $ 2,271 $ 2,125

Regulatory Matters (Tables)

Regulatory Matters (Tables)	12 Months Ended
	Dec. 31, 2019
Regulatory Assets and Liabilities Disclosure [Abstract]
Schedule of Regulatory Assets	The following are balances and a brief description of the Registrants' Regulatory assets and liabilities at December 31: DTE Energy DTE Electric 2019 2018 2019 2018 Assets (In millions) Recoverable pension and other postretirement costs Pension $ 1,983 $ 1,961 $ 1,497 $ 1,476 Other postretirement costs 201 213 131 121 Fermi 2 asset retirement obligation 669 778 669 778 Recoverable undepreciated costs on retiring plants 657 630 657 630 Recoverable Michigan income taxes 189 201 152 161 Deferred environmental costs 66 69 — — Recoverable income taxes related to AFUDC equity 56 51 47 41 Unamortized loss on reacquired debt 56 60 40 43 Customer360 deferred costs 55 42 55 42 Energy Waste Reduction incentive 54 49 43 39 Nuclear Performance Evaluation and Review Committee Tracker 48 43 48 43 Enhanced Tree Trimming Program deferred costs 43 — 43 — Other recoverable income taxes 20 23 20 23 Non-service pension and other postretirement costs 15 10 — — Transitional Reconciliation Mechanism 10 21 10 21 Accrued PSCR/GCR revenue 3 116 3 116 Removal costs asset — 407 — 407 Other 51 47 38 36 4,176 4,721 3,453 3,977 Less amount included in Current Assets (5 ) (153 ) (5 ) (148 ) $ 4,171 $ 4,568 $ 3,448 $ 3,829
Schedule of Regulatory Liabilities	DTE Energy DTE Electric 2019 2018 2019 2018 Liabilities (In millions) Refundable federal income taxes $ 2,359 $ 2,410 $ 1,911 $ 1,958 Removal costs liability 700 253 483 — Negative other postretirement offset 93 101 69 79 Renewable energy 54 86 54 86 Non-service pension and other postretirement costs 46 22 21 11 Accrued PSCR/GCR refund 23 — — — TCJA rate reduction liability 1 118 — 93 Other 53 58 48 42 3,329 3,048 2,586 2,269 Less amount included in Current Liabilities (65 ) (126 ) (40 ) (98 ) $ 3,264 $ 2,922 $ 2,546 $ 2,171

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Schedule of Effective Income Tax Rate Reconciliation	The Registrants' total Income Tax Expense varied from the statutory federal income tax rate for the following reasons: 2019 2018 2017 DTE Energy (In millions) Income Before Income Taxes $ 1,324 $ 1,216 $ 1,287 Income tax expense at statutory rate - 21% in 2019 and 2018 - 35% in 2017 $ 278 $ 255 $ 450 Production tax credits (128 ) (223 ) (189 ) Investment tax credits (4 ) (4 ) (4 ) TCJA regulatory liability amortization (38 ) — — Depreciation 2 2 (4 ) Noncontrolling interests — 2 8 AFUDC equity (4 ) (14 ) (18 ) Employee Stock Ownership Plan dividends (3 ) (3 ) (5 ) Stock based compensation (7 ) (3 ) (14 ) State and local income taxes, net of federal benefit 48 60 51 Enactment of the Tax Cuts and Jobs Act — 21 (105 ) Other, net 8 5 5 Income Tax Expense $ 152 $ 98 $ 175 Effective income tax rate 11.5 % 8.1 % 13.6 % 2019 2018 2017 DTE Electric (In millions) Income Before Income Taxes $ 854 $ 857 $ 928 Income tax expense at statutory rate - 21% in 2019 and 2018 - 35% in 2017 $ 179 $ 180 $ 325 Production tax credits (45 ) (35 ) (36 ) Investment tax credits (4 ) (3 ) (4 ) TCJA regulatory liability amortization (35 ) — — Depreciation 2 2 3 AFUDC equity (4 ) (3 ) (5 ) Employee Stock Ownership Plan dividends (2 ) (2 ) (3 ) State and local income taxes, net of federal benefit 49 49 48 Enactment of the Tax Cuts and Jobs Act — 7 — Other, net (2 ) (2 ) (1 ) Income Tax Expense $ 138 $ 193 $ 327 Effective income tax rate 16.2 % 22.5 % 35.2 %
Schedule of Components of Income Tax Expense (Benefit)	Components of the Registrants' Income Tax Expense were as follows: 2019 2018 2017 DTE Energy (In millions) Current income tax expense (benefit) Federal $ (184 ) $ (17 ) $ (22 ) State and other income tax 7 1 1 Total current income taxes (177 ) (16 ) (21 ) Deferred income tax expense Federal 275 38 118 State and other income tax 54 76 78 Total deferred income taxes 329 114 196 $ 152 $ 98 $ 175 2019 2018 2017 DTE Electric (In millions) Current income tax expense (benefit) Federal $ 25 $ — $ (17 ) State and other income tax 16 4 (1 ) Total current income taxes 41 4 (18 ) Deferred income tax expense Federal 51 131 270 State and other income tax 46 58 75 Total deferred income taxes 97 189 345 $ 138 $ 193 $ 327
Schedule of Deferred Tax Assets and Liabilities	The Registrants' deferred tax assets (liabilities) were comprised of the following at December 31: DTE Energy DTE Electric 2019 2018 2019 2018 (In millions) Property, plant, and equipment $ (3,755 ) $ (3,462 ) $ (2,956 ) $ (2,840 ) Regulatory assets and liabilities (47 ) (54 ) 4 (3 ) Tax credit carry-forwards 1,161 1,178 252 250 Pension and benefits 300 311 258 258 Federal net operating loss carry-forward 276 117 — 2 State and local net operating loss carry-forwards 117 59 — 1 Investments in equity method investees (465 ) (216 ) — (1 ) Other 138 125 87 87 (2,275 ) (1,942 ) (2,355 ) (2,246 ) Less valuation allowance (40 ) (33 ) — — Long-term deferred income tax liabilities $ (2,315 ) $ (1,975 ) $ (2,355 ) $ (2,246 ) Deferred income tax assets $ 2,264 $ 2,021 $ 865 $ 855 Deferred income tax liabilities (4,579 ) (3,996 ) (3,220 ) (3,101 ) $ (2,315 ) $ (1,975 ) $ (2,355 ) $ (2,246 )
Schedule of Unrecognized Tax Benefits Roll Forward	A reconciliation of the beginning and ending amount of unrecognized tax benefits for the Registrants is as follows: 2019 2018 2017 DTE Energy (In millions) Balance at January 1 $ 10 $ 10 $ 10 Additions for tax positions of prior years — — — Balance at December 31 $ 10 $ 10 $ 10 2019 2018 2017 DTE Electric (In millions) Balance at January 1 $ 13 $ 13 $ 13 Additions for tax positions of prior years — — — Balance at December 31 $ 13 $ 13 $ 13

Common Stock and Earnings Per_2

Common Stock and Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2019
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The following is a reconciliation of DTE Energy's basic and diluted income per share calculation for the years ended December 31 : 2019 2018 2017 (In millions, except per share amounts) Basic Earnings per Share Net Income Attributable to DTE Energy Company $ 1,169 $ 1,120 $ 1,134 Less: Allocation of earnings to net restricted stock awards (2 ) (2 ) (2 ) Net income available to common shareholders — basic $ 1,167 $ 1,118 $ 1,132 Average number of common shares outstanding — basic 185 181 179 Basic Earnings per Common Share $ 6.32 $ 6.18 $ 6.32 Diluted Earnings per Share Net Income Attributable to DTE Energy Company $ 1,169 $ 1,120 $ 1,134 Less: Allocation of earnings to net restricted stock awards (2 ) (2 ) (2 ) Net income available to common shareholders — diluted $ 1,167 $ 1,118 $ 1,132 Average number of common shares outstanding - diluted 185 181 179 Diluted Earnings per Common Share (a) $ 6.31 $ 6.17 $ 6.32 _______________________________________ (a) Equity Units excluded from the calculation of diluted EPS were approximately 9.9 million for the year ended December 31, 2019 and 6.3 million for the years ended December 31, 2018 and 2017 , as the dilutive stock price threshold was not met. For more information, see Note 15 to the Consolidated Financial Statements, " Long-Term Debt ."

Fair Value (Tables)

Fair Value (Tables)	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Assets and Liabilities Recorded at Fair Value on a Recurring Basis	The following table presents assets and liabilities for DTE Energy measured and recorded at fair value on a recurring basis (a) : December 31, 2019 December 31, 2018 Level 1 Level 2 Level 3 Other (b) Netting (c) Net Balance Level 1 Level 2 Level 3 Other (b) Netting (c) Net Balance (In millions) Assets Cash equivalents (d) $ 15 $ — $ — $ — $ — $ 15 $ 16 $ 2 $ — $ — $ — $ 18 Nuclear decommissioning trusts Equity securities 1,046 — — — — 1,046 851 — — — — 851 Fixed income securities 160 378 — — — 538 12 490 — — — 502 Private equity and other — — — 43 — 43 — — — 20 — 20 Cash equivalents 34 — — — — 34 5 — — — — 5 Other investments (e) Equity securities 140 — — — — 140 110 — — — — 110 Fixed income securities 79 — — — — 79 69 — — — — 69 Cash equivalents 4 — — — — 4 4 — — — — 4 Derivative assets Commodity contracts Natural gas 205 76 74 — (266 ) 89 199 87 63 — (277 ) 72 Electricity — 223 83 — (225 ) 81 — 247 56 — (252 ) 51 Environmental & Other — 110 3 — (110 ) 3 — — 7 — (1 ) 6 Foreign currency exchange contracts — 1 — — — 1 — 4 — — — 4 Total derivative assets 205 410 160 — (601 ) 174 199 338 126 — (530 ) 133 Total $ 1,683 $ 788 $ 160 $ 43 $ (601 ) $ 2,073 $ 1,266 $ 830 $ 126 $ 20 $ (530 ) $ 1,712 Liabilities Derivative liabilities Commodity contracts Natural gas $ (221 ) $ (41 ) $ (89 ) $ — $ 266 $ (85 ) $ (197 ) $ (71 ) $ (112 ) $ — $ 272 $ (108 ) Electricity — (231 ) (67 ) — 225 (73 ) — (227 ) (58 ) — 240 (45 ) Environmental & Other — (121 ) — — 110 (11 ) — (1 ) — — 1 — Interest rate contracts — — — — — — — (3 ) — — — (3 ) Total $ (221 ) $ (393 ) $ (156 ) $ — $ 601 $ (169 ) $ (197 ) $ (302 ) $ (170 ) $ — $ 513 $ (156 ) Net Assets (Liabilities) at end of period $ 1,462 $ 395 $ 4 $ 43 $ — $ 1,904 $ 1,069 $ 528 $ (44 ) $ 20 $ (17 ) $ 1,556 Assets Current $ 218 $ 320 $ 123 $ — $ (513 ) $ 148 $ 212 $ 273 $ 96 $ — $ (461 ) $ 120 Noncurrent 1,465 468 37 43 (88 ) 1,925 1,054 557 30 20 (69 ) 1,592 Total Assets $ 1,683 $ 788 $ 160 $ 43 $ (601 ) $ 2,073 $ 1,266 $ 830 $ 126 $ 20 $ (530 ) $ 1,712 Liabilities Current $ (211 ) $ (300 ) $ (85 ) $ — $ 513 $ (83 ) $ (191 ) $ (251 ) $ (76 ) $ — $ 451 $ (67 ) Noncurrent (10 ) (93 ) (71 ) — 88 (86 ) (6 ) (51 ) (94 ) — 62 (89 ) Total Liabilities $ (221 ) $ (393 ) $ (156 ) $ — $ 601 $ (169 ) $ (197 ) $ (302 ) $ (170 ) $ — $ 513 $ (156 ) Net Assets (Liabilities) at end of period $ 1,462 $ 395 $ 4 $ 43 $ — $ 1,904 $ 1,069 $ 528 $ (44 ) $ 20 $ (17 ) $ 1,556 _______________________________________ (a) See footnotes on following page. _______________________________________ (b) Amounts represent assets valued at NAV as a practical expedient for fair value. (c) Amounts represent the impact of master netting agreements that allow DTE Energy to net gain and loss positions and cash collateral held or placed with the same counterparties. (d) At December 31, 2019 , the $15 million consisted of $4 million and $11 million of cash equivalents included in Cash and Cash equivalents and Other investments on DTE Energy's Consolidated Statements of Financial Position, respectively. At December 31, 2018 , the $18 million consisted of $3 million , $5 million , and $10 million of cash equivalents included in Cash and Cash equivalents, Restricted cash, and Other investments on DTE Energy's Consolidated Statements of Financial Position, respectively. (e) Excludes cash surrender value of life insurance investments. The following table presents assets for DTE Electric measured and recorded at fair value on a recurring basis as of: December 31, 2019 December 31, 2018 Level 1 Level 2 Level 3 Other (a) Net Balance Level 1 Level 2 Level 3 Other (a) Net Balance (In millions) Assets Cash equivalents (b) $ 11 $ — $ — $ — $ 11 $ 8 $ 2 $ — $ — $ 10 Nuclear decommissioning trusts Equity securities 1,046 — — — 1,046 851 — — — 851 Fixed income securities 160 378 — — 538 12 490 — — 502 Private equity and other — — — 43 43 — — — 20 20 Cash equivalents 34 — — — 34 5 — — — 5 Other investments Equity securities 13 — — — 13 10 — — — 10 Derivative assets — FTRs — — 3 — 3 — — 6 — 6 Total $ 1,264 $ 378 $ 3 $ 43 $ 1,688 $ 886 $ 492 $ 6 $ 20 $ 1,404 Assets Current $ 11 $ — $ 3 $ — $ 14 $ 8 $ 2 $ 6 $ — $ 16 Noncurrent 1,253 378 — 43 1,674 878 490 — 20 1,388 Total Assets $ 1,264 $ 378 $ 3 $ 43 $ 1,688 $ 886 $ 492 $ 6 $ 20 $ 1,404 _______________________________________ (a) Amounts represent assets valued at NAV as a practical expedient for fair value. (b) At December 31, 2019 , the $11 million consisted of cash equivalents included in Other investments on DTE Electric's Consolidated Statements of Financial Position. At December 31, 2018 , the $10 million consisted of cash equivalents included in Other investments on DTE Electric's Consolidated Statements of Financial Position.
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis Level 3 Roll Forward	The following table presents the fair value reconciliation of Level 3 assets and liabilities measured at fair value on a recurring basis for DTE Energy: Year Ended December 31, 2019 Year Ended December 31, 2018 Natural Gas Electricity Other Total Natural Gas Electricity Other Total (In millions) Net Assets (Liabilities) as of January 1 $ (49 ) $ (2 ) $ 7 $ (44 ) $ (29 ) $ 12 $ 8 $ (9 ) Transfers from Level 3 into Level 2 — — — — (3 ) — — (3 ) Total gains (losses) Included in earnings 15 77 (1 ) 91 (146 ) 29 1 (116 ) Recorded in Regulatory liabilities — — 2 2 — — 9 9 Purchases, issuances, and settlements: Settlements 19 (59 ) (5 ) (45 ) 129 (43 ) (11 ) 75 Net Assets (Liabilities) as of December 31 $ (15 ) $ 16 $ 3 $ 4 $ (49 ) $ (2 ) $ 7 $ (44 ) The amount of total gains (losses) included in Net Income attributed to the change in unrealized gains (losses) related to assets and liabilities held at December 31, 2019 and 2018 and reflected in Operating Revenues — Non-utility operations and Fuel, purchased power, and gas — non-utility in DTE Energy's Consolidated Statements of Operations $ (1 ) $ 59 $ (38 ) $ 20 $ (119 ) $ 15 $ (16 ) $ (120 ) The following table presents the fair value reconciliation of Level 3 assets and liabilities measured at fair value on a recurring basis for DTE Electric: Year Ended December 31, 2019 2018 (In millions) Net Assets as of January 1 $ 6 $ 9 Change in fair value recorded in Regulatory liabilities 2 9 Purchases, issuances, and settlements: Settlements (5 ) (12 ) Net Assets as of December 31 $ 3 $ 6 The amount of total gains (losses) included in Regulatory liabilities attributed to the change in unrealized gains (losses) related to assets and liabilities held at December 31, 2019 and 2018 and reflected in DTE Electric's Consolidated Statements of Financial Position $ 3 $ 6
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques	The following tables present the unobservable inputs related to DTE Energy's Level 3 assets and liabilities: December 31, 2019 Commodity Contracts Derivative Assets Derivative Liabilities Valuation Techniques Unobservable Input Range Weighted Average (In millions) Natural Gas $ 74 $ (89 ) Discounted Cash Flow Forward basis price (per MMBtu) $ (1.78 ) — $ 5.78 /MMBtu $ (0.09 )/MMBtu Electricity $ 83 $ (67 ) Discounted Cash Flow Forward basis price (per MWh) $ (10 ) — $ 6 /MWh $ — December 31, 2018 Commodity Contracts Derivative Assets Derivative Liabilities Valuation Techniques Unobservable Input Range Weighted Average (In millions) Natural Gas $ 63 $ (112 ) Discounted Cash Flow Forward basis price (per MMBtu) $ (2.15 ) — $ 5.59 /MMBtu $ (0.10 )/MMBtu Electricity $ 56 $ (58 ) Discounted Cash Flow Forward basis price (per MWh) $ (7 ) — $ 9 /MWh $ 1 /MWh
Fair Value of Financial Instruments	The following table presents the carrying amount and fair value of financial instruments for DTE Energy: December 31, 2019 December 31, 2018 Carrying Fair Value Carrying Fair Value Amount Level 1 Level 2 Level 3 Amount Level 1 Level 2 Level 3 (In millions) Notes receivable — Other (a) , excluding lessor finance leases $ 184 $ — $ — $ 184 $ 40 $ — $ — $ 40 Dividends payable $ 195 $ 195 $ — $ — $ 172 $ 172 $ — $ — Short-term borrowings $ 828 $ — $ 828 $ — $ 609 $ — $ 609 $ — Notes payable — Other (b) , excluding lessee finance leases $ 25 $ — $ — $ 25 $ 41 $ — $ — $ 41 Long-term debt (c) $ 16,606 $ 2,572 $ 14,207 $ 1,252 $ 13,622 $ 1,796 $ 10,712 $ 1,317 _______________________________________ (a) Current portion included in Current Assets — Other on DTE Energy's Consolidated Statements of Financial Position. (b) Included in Current Liabilities — Other and Other Liabilities — Other on DTE Energy's Consolidated Statements of Financial Position. (c) Includes debt due within one year, unamortized debt discounts, and issuance costs. Excludes finance lease obligations. The following table presents the carrying amount and fair value of financial instruments for DTE Electric: December 31, 2019 December 31, 2018 Carrying Fair Value Carrying Fair Value Amount Level 1 Level 2 Level 3 Amount Level 1 Level 2 Level 3 (In millions) Notes receivable — Other (a) , excluding lessor finance leases $ 9 $ — $ — $ 9 $ 6 $ — $ — $ 6 Short-term borrowings — affiliates $ 97 $ — $ — $ 97 $ 101 $ — $ — $ 101 Short-term borrowings — other $ 354 $ — $ 354 $ — 149 $ — $ 149 $ — Notes payable — Other (b) , excluding lessee finance leases $ 21 $ — $ — $ 21 $ 21 $ — $ — $ 21 Long-term debt (c) $ 7,180 $ — $ 7,916 $ 173 $ 6,538 $ — $ 6,552 $ 161 _______________________________________ (a) Included in Current Assets — Other on DTE Electric's Consolidated Statements of Financial Position. (b) Included in Current Liabilities — Other and Other Liabilities — Other on DTE Electric's Consolidated Statements of Financial Position. (c) Includes debt due within one year, unamortized debt discounts, and issuance costs. Excludes finance lease obligations.
Fair Value of Nuclear Decommissioning Trust Fund Assets	The following table summarizes DTE Electric's fair value of the nuclear decommissioning trust fund assets: December 31, 2019 2018 (In millions) Fermi 2 $ 1,650 $ 1,372 Fermi 1 3 3 Low-level radioactive waste 8 3 $ 1,661 $ 1,378
Schedule of Realized Gain (Loss) for Nuclear Decommissioning Trust Funds	The following table sets forth DTE Electric's gains and losses and proceeds from the sale of securities by the nuclear decommissioning trust funds: Year Ended December 31, 2019 2018 2017 (In millions) Realized gains $ 56 $ 65 $ 83 Realized losses $ (31 ) $ (42 ) $ (29 ) Proceeds from sale of securities $ 788 $ 1,203 $ 1,240
Fair Value and Unrealized Gains and Losses for Nuclear Decommissioning Trust Funds	The following table sets forth DTE Electric's fair value and unrealized gains and losses for the nuclear decommissioning trust funds: December 31, 2019 December 31, 2018 Fair Unrealized Unrealized Losses Fair Unrealized Unrealized Losses (In millions) Equity securities $ 1,046 $ 396 $ (39 ) $ 851 $ 235 $ (79 ) Fixed income securities 538 24 (1 ) 502 7 (8 ) Private equity and other 43 — — 20 — — Cash equivalents 34 — — 5 — — $ 1,661 $ 420 $ (40 ) $ 1,378 $ 242 $ (87 )
Fair Value of the Fixed Income Securities Held in Nuclear Decommissioning Trust Funds	The following table summarizes the fair value of the fixed income securities held in nuclear decommissioning trust funds by contractual maturity: December 31, 2019 (In millions) Due within one year $ 15 Due after one through five years 102 Due after five through ten years 109 Due after ten years 312 $ 538

Financial and Other Derivativ_2

Financial and Other Derivative Instruments (Tables)	12 Months Ended
	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair Value of Derivative Instruments	The following table presents the fair value of derivative instruments for DTE Energy: December 31, 2019 December 31, 2018 Derivative Derivative Derivative Derivative (In millions) Derivatives designated as hedging instruments Interest rate contracts $ — $ — $ — $ (3 ) Derivatives not designated as hedging instruments Commodity contracts Natural gas $ 355 $ (351 ) $ 349 $ (380 ) Electricity 306 (298 ) 303 (285 ) Environmental & Other 113 (121 ) 7 (1 ) Foreign currency exchange contracts 1 — 4 — Total derivatives not designated as hedging instruments $ 775 $ (770 ) $ 663 $ (666 ) Current $ 646 $ (596 ) $ 563 $ (518 ) Noncurrent 129 (174 ) 100 (151 ) Total derivatives $ 775 $ (770 ) $ 663 $ (669 ) The following table presents the fair value of derivative instruments for DTE Electric: December 31, 2019 2018 (In millions) FTRs — Other current assets $ 3 $ 6 Total derivatives not designated as hedging instruments $ 3 $ 6
Offsetting Assets	The following table presents net cash collateral offsetting arrangements for DTE Energy: December 31, 2019 2018 (In millions) Cash collateral netted against Derivative assets $ — $ (17 ) Cash collateral recorded in Accounts receivable (a) 13 10 Cash collateral recorded in Accounts payable (a) (3 ) (6 ) Total net cash collateral posted (received) $ 10 $ (13 ) _______________________________________ (a) Amounts are recorded net by counterparty. The following table presents the netting offsets of Derivative assets and liabilities for DTE Energy: December 31, 2019 December 31, 2018 Gross Amounts of Recognized Assets (Liabilities) Gross Amounts Offset in the Consolidated Statements of Financial Position Net Amounts of Assets (Liabilities) Presented in the Consolidated Statements of Financial Position Gross Amounts of Recognized Assets (Liabilities) Gross Amounts Offset in the Consolidated Statements of Financial Position Net Amounts of Assets (Liabilities) Presented in the Consolidated Statements of Financial Position (In millions) Derivative assets Commodity contracts Natural gas $ 355 $ (266 ) $ 89 $ 349 $ (277 ) $ 72 Electricity 306 (225 ) 81 303 (252 ) 51 Environmental & Other 113 (110 ) 3 7 (1 ) 6 Foreign currency exchange contracts 1 — 1 4 — 4 Total derivative assets $ 775 $ (601 ) $ 174 $ 663 $ (530 ) $ 133 Derivative liabilities Commodity contracts Natural gas $ (351 ) $ 266 $ (85 ) $ (380 ) $ 272 $ (108 ) Electricity (298 ) 225 (73 ) (285 ) 240 (45 ) Environmental & Other (121 ) 110 (11 ) (1 ) 1 — Interest rate contracts — — — (3 ) — (3 ) Total derivative liabilities $ (770 ) $ 601 $ (169 ) $ (669 ) $ 513 $ (156 )
Offsetting Liabilities	The following table presents net cash collateral offsetting arrangements for DTE Energy: December 31, 2019 2018 (In millions) Cash collateral netted against Derivative assets $ — $ (17 ) Cash collateral recorded in Accounts receivable (a) 13 10 Cash collateral recorded in Accounts payable (a) (3 ) (6 ) Total net cash collateral posted (received) $ 10 $ (13 ) _______________________________________ (a) Amounts are recorded net by counterparty. The following table presents the netting offsets of Derivative assets and liabilities for DTE Energy: December 31, 2019 December 31, 2018 Gross Amounts of Recognized Assets (Liabilities) Gross Amounts Offset in the Consolidated Statements of Financial Position Net Amounts of Assets (Liabilities) Presented in the Consolidated Statements of Financial Position Gross Amounts of Recognized Assets (Liabilities) Gross Amounts Offset in the Consolidated Statements of Financial Position Net Amounts of Assets (Liabilities) Presented in the Consolidated Statements of Financial Position (In millions) Derivative assets Commodity contracts Natural gas $ 355 $ (266 ) $ 89 $ 349 $ (277 ) $ 72 Electricity 306 (225 ) 81 303 (252 ) 51 Environmental & Other 113 (110 ) 3 7 (1 ) 6 Foreign currency exchange contracts 1 — 1 4 — 4 Total derivative assets $ 775 $ (601 ) $ 174 $ 663 $ (530 ) $ 133 Derivative liabilities Commodity contracts Natural gas $ (351 ) $ 266 $ (85 ) $ (380 ) $ 272 $ (108 ) Electricity (298 ) 225 (73 ) (285 ) 240 (45 ) Environmental & Other (121 ) 110 (11 ) (1 ) 1 — Interest rate contracts — — — (3 ) — (3 ) Total derivative liabilities $ (770 ) $ 601 $ (169 ) $ (669 ) $ 513 $ (156 )
Netting Offsets of Derivative Assets and Liabilities Reconciliation to the Statements of Financial Position	The following table presents the netting offsets of Derivative assets and liabilities showing the reconciliation of derivative instruments to DTE Energy's Consolidated Statements of Financial Position: December 31, 2019 December 31, 2018 Derivative Assets Derivative Liabilities Derivative Assets Derivative Liabilities Current Noncurrent Current Noncurrent Current Noncurrent Current Noncurrent (In millions) Total fair value of derivatives $ 646 $ 129 $ (596 ) $ (174 ) $ 563 $ 100 $ (518 ) $ (151 ) Counterparty netting (513 ) (88 ) 513 88 (451 ) (62 ) 451 62 Collateral adjustment — — — — (10 ) (7 ) — — Total derivatives as reported $ 133 $ 41 $ (83 ) $ (86 ) $ 102 $ 31 $ (67 ) $ (89 )
Gain (Loss) Recognized in Income on Derivatives	The effect of derivatives not designated as hedging instruments on DTE Energy's Consolidated Statements of Operations is as follows: Location of Gain (Loss) Recognized in Income on Derivatives Gain (Loss) Recognized in Income on Derivatives for Years Ended December 31, 2019 2018 2017 (In millions) Commodity contracts Natural gas Operating Revenues — Non-utility operations $ 44 $ (42 ) $ (74 ) Natural gas Fuel, purchased power, and gas — non-utility (5 ) (94 ) 97 Electricity Operating Revenues — Non-utility operations 44 49 105 Environmental & Other Operating Revenues — Non-utility operations (26 ) (1 ) 2 Foreign currency exchange contracts Operating Revenues — Non-utility operations (2 ) 7 (2 ) Total $ 55 $ (81 ) $ 128
Volume of Commodity Contracts	The following represents the cumulative gross volume of DTE Energy's derivative contracts outstanding as of December 31, 2019 : Commodity Number of Units Natural gas (MMBtu) 1,699,804,805 Electricity (MWh) 31,351,229 Foreign currency exchange (CAD) 78,563,487

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2019
Long-term Debt, Unclassified [Abstract]
Schedule of Long-term Debt Instruments	DTE Energy's long-term debt outstanding and weighted average interest rates of debt outstanding at December 31 were: Interest Rate (a) Maturity Date 2019 2018 (In millions) Mortgage bonds, notes, and other DTE Energy Debt, Unsecured 3.2% 2022 — 2033 $ 6,625 $ 4,425 DTE Electric Taxable Debt, Principally Secured 4.2% 2020 — 2049 6,930 6,280 DTE Electric Tax-Exempt Revenue Bonds (b) 4.3% 2020 — 2030 310 310 DTE Gas Taxable Debt, Principally Secured 4.3% 2020 — 2049 1,710 1,550 Other Long-Term Debt, including Non-Recourse Debt — 1 15,575 12,566 Unamortized debt discount (24 ) (16 ) Unamortized debt issuance costs (91 ) (73 ) Long-term debt due within one year (682 ) (1,495 ) $ 14,778 $ 10,982 Junior Subordinated Debentures Subordinated Debentures 5.5% 2062 — 2077 $ 1,180 $ 1,180 Unamortized debt issuance costs (34 ) (35 ) $ 1,146 $ 1,145 _______________________________________ (a) Weighted average interest rate as of December 31, 2019 . (b) DTE Electric Tax-Exempt Revenue Bonds are issued by a public body that loans the proceeds to DTE Electric on terms substantially mirroring the Revenue Bonds. DTE Electric's long-term debt outstanding and weighted average interest rates of debt outstanding at December 31 were: Interest Rate (a) Maturity Date 2019 2018 (In millions) Mortgage bonds, notes, and other Taxable Debt, Principally Secured 4.2% 2020 — 2049 $ 6,930 $ 6,280 Tax-Exempt Revenue Bonds (b) 4.3% 2020 — 2030 310 310 7,240 6,590 Unamortized debt discount (15 ) (11 ) Unamortized debt issuance costs (45 ) (41 ) Long-term debt due within one year (632 ) — $ 6,548 $ 6,538 _______________________________________ (a) Weighted average interest rate as of December 31, 2019 . (b) Tax-Exempt Revenue Bonds are issued by a public body that loans the proceeds to DTE Electric on terms substantially mirroring the Revenue Bonds. Selected information about DTE Energy’s 2019 Equity Units is presented below: Issuance Date Units Issued Total Net Proceeds Total Long-Term Debt RSN Annual Interest Rate Stock Purchase Contract Annual Rate Stock Purchase Settlement Date Stock Purchase Contract Liability RSN Maturity Date (In millions, except interest rates) 11/1/19 26 $ 1,268 $ 1,300 2.25% 4.0% 11/1/2022 $ 150 11/1/2025
Schedule of Issued Debt	In 2019 , the following debt was issued: Company Month Type Interest Rate Maturity Date Amount (In millions) DTE Electric February Mortgage Bonds (a) 3.95% 2049 $ 650 DTE Energy June Senior Notes (b) 2.60% 2022 300 DTE Energy June Senior Notes (b) 3.40% 2029 500 DTE Gas October Mortgage Bonds (b) 2.95% 2029 140 DTE Gas October Mortgage Bonds (b) 3.72% 2049 140 DTE Energy November Senior Notes (c) 2.25% 2022 500 DTE Energy November Senior Notes (c) 2.95% 2030 300 DTE Energy November Equity Units (c) (d) 2025 1,300 $ 3,830 _______________________________________ (a) Bonds were issued as Green Bonds and the proceeds will be used to finance expenditures for solar and wind energy, payments under power purchase agreements for solar and wind energy, and energy optimization programs. (b) Proceeds were used for the repayment of short-term borrowings and general corporate purposes. (c) Proceeds were used to pay a portion of the purchase price of the Blue Union and LEAP acquisition. Refer to "Acquisition Financing" below for additional information. (d) See "Acquisition Financing" below for more information regarding the rates associated with the Equity Units.
Schedule of Debt Redeemed	In 2019 , the following debt was redeemed: Company Month Type Interest Rate Maturity Date Amount (In millions) DTE Energy October Senior Notes 1.50% 2019 $ 400 DTE Gas October Senior Notes 5.00% 2019 120 DTE Energy December Senior Notes 2.40% 2019 300 DTE Energy Various Other long-term debt Various 2019 1 $ 821
Schedule of Maturities of Long-term Debt	The following table shows the Registrants' scheduled debt maturities, excluding any unamortized discount on debt: 2020 2021 2022 2023 2024 2025 and Thereafter Total (In millions) DTE Energy (a) $ 682 $ 462 $ 2,716 $ 1,177 $ 1,425 $ 10,293 $ 16,755 DTE Electric $ 632 $ 462 $ 316 $ 202 $ 400 $ 5,228 $ 7,240 _______________________________________ (a) Amounts include DTE Electric's scheduled debt maturities.

Preferred and Preference Secu_2

Preferred and Preference Securities (Tables)	12 Months Ended
	Dec. 31, 2019
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Schedule of Preferred and Preference Securities	As of December 31, 2019 , the amount of authorized and unissued stock is as follows: Company Type of Stock Par Value Shares Authorized DTE Energy Preferred $ — 5,000,000 DTE Electric Preferred $ 100 6,747,484 DTE Electric Preference $ 1 30,000,000 DTE Gas Preferred $ 1 7,000,000 DTE Gas Preference $ 1 4,000,000

Short-Term Credit Arrangement_2

Short-Term Credit Arrangements and Borrowings (Tables)	12 Months Ended
	Dec. 31, 2019
Short-term Debt [Abstract]
Schedule of Line of Credit Facilities	The availability under the facilities in place at December 31, 2019 is shown in the following table: DTE Energy DTE Electric DTE Gas Total (In millions) Unsecured letter of credit facility, expiring in February 2021 $ 150 $ — $ — $ 150 Unsecured letter of credit facility, expiring in August 2021 110 — — 110 Unsecured revolving credit facility, expiring April 2024 1,500 500 300 2,300 1,760 500 300 2,560 Amounts outstanding at December 31, 2019 Commercial paper issuances 280 354 194 828 Letters of credit 229 — — 229 509 354 194 1,057 Net availability at December 31, 2019 $ 1,251 $ 146 $ 106 $ 1,503

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2019
Leases [Abstract]
Components of Lease Cost and Other Information Related to Leases	The components of lease cost for the year ended December 31, 2019 were as follows: DTE Energy DTE Electric (In millions) Operating lease cost $ 41 $ 17 Finance lease cost: Amortization of right-of-use assets 4 4 Interest of lease liabilities — — Total finance lease cost 4 4 Variable lease cost 10 — Short-term lease cost 10 3 $ 65 $ 24 Other information related to leases for the year ended December 31, 2019 were as follows: DTE Energy DTE Electric (In millions) Supplemental Cash Flows Information Cash paid for amounts included in the measurement of these liabilities: Operating cash flows for finance leases $ 5 $ 5 Operating cash flows for operating leases $ 40 $ 16 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 68 $ 27 Finance leases $ 8 $ — Weighted Average Remaining Lease Term Operating leases 9.7 years 10.6 years Finance leases 9.1 years 2.0 years Weighted Average Discount Rate Operating leases 3.5% 3.3% Finance leases 3.1% 3.1%
Schedule of Maturities of Operating Leases	The Registrants' future minimum lease payments under leases for remaining periods as of December 31, 2019 were as follows: DTE Energy DTE Electric Operating Leases Finance Leases Operating Leases Finance Leases (In millions) 2020 $ 38 $ 5 $ 14 $ 3 2021 30 5 13 4 2022 26 1 12 — 2023 20 1 10 — 2024 12 1 8 — 2025 and thereafter 67 4 38 — Total future minimum lease payments 193 17 95 7 Imputed interest (33 ) (2 ) (16 ) — $ 160 $ 15 $ 79 $ 7
Schedule of Maturities of Finance Leases	The Registrants' future minimum lease payments under leases for remaining periods as of December 31, 2019 were as follows: DTE Energy DTE Electric Operating Leases Finance Leases Operating Leases Finance Leases (In millions) 2020 $ 38 $ 5 $ 14 $ 3 2021 30 5 13 4 2022 26 1 12 — 2023 20 1 10 — 2024 12 1 8 — 2025 and thereafter 67 4 38 — Total future minimum lease payments 193 17 95 7 Imputed interest (33 ) (2 ) (16 ) — $ 160 $ 15 $ 79 $ 7
Schedule of Finance Leases Reported on Consolidated Statement of Financial Position	Finance leases reported on the Consolidated Statement of Financial Position were as follows: DTE Energy DTE Electric December 31, 2019 (In millions) Right-of-use assets, within Property, plant, and equipment, net $ 15 $ 7 Current lease liabilities, within Current Liabilities — Other $ 4 $ 3
Schedule of Future Minimum Lease Payments and Rental Revenues for Operating Leases	The Registrants' future minimum lease payments under non-cancelable operating leases at December 31, 2018 were as follows: DTE Energy DTE Electric (In millions) 2019 $ 42 $ 17 2020 30 12 2021 18 10 2022 11 7 2023 8 5 2024 and thereafter 45 29 $ 154 $ 80 DTE Energy’s minimum future rental revenues under non-cancelable operating leases as of December 31, 2018 were as follows: DTE Energy (In millions) 2019 $ 66 2020 66 2021 64 2022 20 2023 20 2024 and thereafter 196 $ 432
Schedule of property under capital leases	The following is a summary of Depreciation and amortization expense for DTE Energy: 2019 2018 2017 (In millions) Property, plant, and equipment $ 997 $ 878 $ 829 Regulatory assets and liabilities 227 212 165 Intangible assets 33 27 29 Other 6 7 7 $ 1,263 $ 1,124 $ 1,030 The following is a summary of Depreciation and amortization expense for DTE Electric: 2019 2018 2017 (In millions) Property, plant, and equipment $ 748 $ 652 $ 615 Regulatory assets and liabilities 193 179 133 Other 5 5 5 $ 946 $ 836 $ 753 The following is a summary of Property, plant, and equipment by classification as of December 31: 2019 2018 Property, plant, and equipment (In millions) DTE Electric Generation $ 12,028 $ 11,027 Distribution 9,715 9,153 Other 2,536 2,567 Total DTE Electric 24,279 22,747 DTE Gas Distribution 4,164 3,823 Storage 570 548 Transmission and other 1,244 1,204 Total DTE Gas 5,978 5,575 Non-utility and other Gas Storage and Pipelines 3,524 2,307 Power and Industrial Projects 1,108 1,070 Other 183 111 Non-utility and other 4,815 3,488 Total DTE Energy 35,072 31,810 Accumulated depreciation and amortization DTE Electric Generation (3,460 ) (3,609 ) Distribution (2,553 ) (2,974 ) Other (693 ) (727 ) Total DTE Electric (6,706 ) (7,310 ) DTE Gas Distribution (1,334 ) (1,283 ) Storage (172 ) (165 ) Transmission and other (409 ) (404 ) Total DTE Gas (1,915 ) (1,852 ) Non-utility and other Gas Storage and Pipelines (459 ) (390 ) Power and Industrial Projects (604 ) (546 ) Other (71 ) (62 ) Non-utility and other (1,134 ) (998 ) Total DTE Energy (9,755 ) (10,160 ) Net DTE Energy Property, plant, and equipment $ 25,317 $ 21,650 Net DTE Electric Property, plant, and equipment $ 17,573 $ 15,437 DTE Energy DTE Electric (In millions) Gross property under capital leases $ 18 $ 18 Accumulated amortization of property under capital leases $ 7 $ 7
Schedule of Lease Income Associated with Operating Leases	DTE Energy’s lease income associated with operating leases was as follows for the year ended December 31, 2019 : DTE Energy (In millions) Fixed payments (a) $ 65 Variable payments (a) 128 $ 193 _______________________________________ (a) Includes $130 million of lease payments reported in Operating Revenues and $63 million of lease payments reported in Other income on DTE Energy's Consolidated Statements of Operations.
Schedule of Minimum Future Rental Revenues under Operating Leases	DTE Energy’s minimum future rental revenues under operating leases for remaining periods as of December 31, 2019 were as follows: DTE Energy (In millions) 2020 $ 64 2021 62 2022 22 2023 22 2024 22 2025 and thereafter 194 $ 386
Schedule of Property under Operating Leases - Topic 842	Property under operating leases for DTE Energy as of December 31, 2019 were as follows: DTE Energy (In millions) Gross property under operating leases $ 445 Accumulated amortization of property under operating leases $ 173
Components of Net Investment in Finance Leases	The components of DTE Energy’s net investment in finance leases for remaining periods as of December 31, 2019 were as follows: DTE Energy (In millions) 2020 $ 9 2021 4 2022 4 2023 5 2024 5 2025 and thereafter 55 Total minimum future lease receipts 82 Residual value of leased pipeline 19 Less unearned income 55 Net investment in finance lease 46 Less current portion 5 $ 41
Components of Net Investment in Capital Leases	The components of DTE Energy’s net investment in capital leases at December 31, 2018 were as follows: DTE Energy (In millions) 2019 $ 10 2020 9 2021 — 2022 — 2023 — 2024 and thereafter 1 Total minimum future lease receipts 20 Residual value of leased pipeline 40 Less unearned income 9 Net investment in capital lease 51 Less current portion 5 $ 46
Schedule of Property under Operating Leases - Topic 840	Property under operating leases for DTE Energy as of December 31, 2018 were as follows: DTE Energy (In millions) Gross property under operating leases $ 447 Accumulated amortization of property under operating leases $ 148

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Schedule of Long-term Purchase Commitments	The Registrants estimate the following commitments from 2020 through 2051 for DTE Energy, and 2020 through 2039 for DTE Electric, as detailed in the following table: DTE Energy DTE Electric (In millions) 2020 $ 3,152 $ 1,556 2021 1,055 299 2022 561 95 2023 418 96 2024 365 96 2025 and thereafter 1,503 688 $ 7,054 $ 2,830

Retirement Benefits and Trust_2

Retirement Benefits and Trusteed Assets (Tables)	12 Months Ended
	Dec. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule of Defined Benefit Plans Disclosures	The table below represents the pension and other postretirement benefit plans of each Registrant at December 31, 2019 : Registrants DTE Energy DTE Electric Qualified Pension Plans DTE Energy Company Retirement Plan X X DTE Gas Company Retirement Plan for Employees Covered by Collective Bargaining Agreements X Shenango Inc. Pension Plan X Nonqualified Pension Plans DTE Energy Company Supplemental Retirement Plan X X DTE Energy Company Executive Supplemental Retirement Plan (a) X X DTE Energy Company Supplemental Severance Benefit Plan X Other Postretirement Benefit Plans The DTE Energy Company Comprehensive Non-Health Welfare Plan X X The DTE Energy Company Comprehensive Retiree Group Health Care Plan X X DTE Supplemental Retiree Benefit Plan X X DTE Energy Company Retiree Reimbursement Arrangement Plan X X _____________________________________ (a) Sponsored by the DTE Energy subsidiary, DTE Energy Holding Company.
Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule of Defined Benefit Plans Disclosures	The following table provides contributions to the qualified pension plans in: 2019 2018 2017 (In millions) DTE Energy $ 150 $ 175 $ 223 DTE Electric $ 100 $ 175 $ 185 During 2019 , DTE Energy contributed the following amounts of DTE Energy common stock to the DTE Energy Company Affiliates Employee Benefit Plans Master Trust: Date Number of Shares Price per Share Amount (In millions) March 5, 2019 814,597 $122.76 $ 100 The following table reconciles the obligations, assets, and funded status of the plans as well as the amounts recognized as prepaid pension cost or pension liability in DTE Energy's Consolidated Statements of Financial Position at December 31: DTE Energy 2019 2018 (In millions) Accumulated benefit obligation, end of year $ 5,387 $ 4,779 Change in projected benefit obligation Projected benefit obligation, beginning of year $ 5,124 $ 5,576 Service cost 84 99 Interest cost 219 202 Actuarial (gain) loss 719 (438 ) Benefits paid (336 ) (315 ) Projected benefit obligation, end of year $ 5,810 $ 5,124 Change in plan assets Plan assets at fair value, beginning of year $ 4,273 $ 4,636 Actual return on plan assets 888 (233 ) Company contributions 168 185 Benefits paid (336 ) (315 ) Plan assets at fair value, end of year $ 4,993 $ 4,273 Funded status $ (817 ) $ (851 ) Amount recorded as: Current liabilities $ (9 ) $ (14 ) Noncurrent liabilities (808 ) (837 ) $ (817 ) $ (851 ) Amounts recognized in Accumulated other comprehensive income (loss), pre-tax Net actuarial loss $ 153 $ 152 Prior service cost 4 5 $ 157 $ 157 Amounts recognized in Regulatory assets (a) Net actuarial loss $ 1,995 $ 1,973 Prior service credit (12 ) (12 ) $ 1,983 $ 1,961 ______________________________________ (a) See Note 10 to the Consolidated Financial Statements, " Regulatory Matters ."
Schedule of Net Benefit Costs	Net pension cost for DTE Energy includes the following components: 2019 2018 2017 (In millions) Service cost $ 84 $ 99 $ 92 Interest cost 219 202 214 Expected return on plan assets (325 ) (329 ) (311 ) Amortization of: Net actuarial loss 133 176 176 Prior service cost 1 — 1 Net pension cost $ 112 $ 148 $ 172
Schedule of Amounts Recognized in Other Comprehensive Income (Loss)	2019 2018 (In millions) Other changes in plan assets and benefit obligations recognized in Regulatory assets and Other comprehensive income (loss) Net actuarial loss $ 156 $ 125 Amortization of net actuarial loss (133 ) (176 ) Amortization of prior service cost (1 ) — Total recognized in Regulatory assets and Other comprehensive income (loss) $ 22 $ (51 ) Total recognized in net periodic pension cost, Regulatory assets, and Other comprehensive income (loss) $ 134 $ 97 Estimated amounts to be amortized from Regulatory assets and Accumulated other comprehensive income (loss) into net periodic benefit cost during next fiscal year Net actuarial loss $ 171 $ 131 Prior service cost $ 1 $ 1
Schedule of Expected Benefit Payments	At December 31, 2019 , the benefits related to DTE Energy's qualified and nonqualified pension plans expected to be paid in each of the next five years and in the aggregate for the five fiscal years thereafter are as follows: (In millions) 2020 $ 311 2021 319 2022 324 2023 330 2024 334 2025-2029 1,723 Total $ 3,341
Schedule of Assumptions Used	Assumptions used in determining the projected benefit obligation and net pension costs of DTE Energy are: 2019 2018 2017 Projected benefit obligation Discount rate 3.28% 4.40% 3.70% Rate of compensation increase 4.98% 4.98% 4.98% Net pension costs Discount rate 4.40% 3.70% 4.25% Rate of compensation increase 4.98% 4.98% 4.65% Expected long-term rate of return on plan assets 7.30% 7.50% 7.50%
Schedule of Allocation of Plan Assets	The following tables provide the fair value measurement amounts for DTE Energy's pension plan assets at December 31, 2019 and 2018 (a) : December 31, 2019 December 31, 2018 Level 1 Level 2 Other (b) Total Level 1 Level 2 Other (b) Total DTE Energy asset category: (In millions) Short-term Investments (c) $ 99 $ — $ — $ 99 $ — $ 27 $ — $ 27 Equity Securities Domestic (d) 172 — 870 1,042 729 4 — 733 International (e) 387 — 322 709 337 9 240 586 Fixed Income Securities Governmental (f) 569 — — 569 — 868 — 868 Corporate (g) — 1,452 — 1,452 6 1,024 — 1,030 Hedge Funds and Similar Investments (h) 169 — 502 671 88 — 542 630 Private Equity and Other (i) — — 451 451 — — 399 399 DTE Energy Total $ 1,396 $ 1,452 $ 2,145 $ 4,993 $ 1,160 $ 1,932 $ 1,181 $ 4,273 _______________________________________ (a) For a description of levels within the fair value hierarchy, see Note 13 to the Consolidated Financial Statements, " Fair Value ." (b) Amounts represent assets valued at NAV as a practical expedient for fair value. (c) This category predominantly represents certain short-term fixed income securities and money market investments that are managed in separate accounts or commingled funds. Pricing for investments in this category are obtained from quoted prices in actively traded markets or valuations from brokers or pricing services. (d) This category represents portfolios of large, medium and small capitalization domestic equities. Investments in this category include exchange-traded securities for which unadjusted quoted prices can be obtained and exchange-traded securities held in a commingled fund classified as NAV assets. (e) This category primarily consists of portfolios of non-U.S. developed and emerging market equities. Investments in this category are exchange-traded securities whereby unadjusted quoted prices can be obtained. Exchange-traded securities held in a commingled fund are classified as NAV assets. (f) This category includes U.S. Treasuries, bonds, and other governmental debt. Pricing for investments in this category is obtained from quoted prices in actively traded markets and quotations from broker or pricing services. (g) This category primarily consists of corporate bonds from diversified industries, bank loans, and mortgage backed securities. Pricing for investments in this category is obtained from quoted prices in actively traded markets and quotations from broker or pricing services. (h) This category utilizes a diversified group of strategies that attempt to capture financial market inefficiencies and includes publicly traded mutual funds, commingled funds and limited partnership funds. Pricing for mutual funds in this category is obtained from quoted prices in actively traded markets. Commingled funds and limited partnership funds are classified as NAV assets. (i) This category includes a diversified group of funds and strategies that primarily invests in private equity partnerships. This category also includes investments in real estate and private debt. All pricing for investments in this category are classified as NAV assets. Target allocations for DTE Energy's pension plan assets as of December 31, 2019 are listed below: U.S. Large Capitalization (Cap) Equity Securities 16 % U.S. Small Cap and Mid Cap Equity Securities 4 Non-U.S. Equity Securities 15 Fixed Income Securities 42 Hedge Funds and Similar Investments 14 Private Equity and Other 9 100 %
Other postretirement benefit plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule of Defined Benefit Plans Disclosures	The following table reconciles the obligations, assets, and funded status of the plans including amounts recorded as Accrued postretirement liability in the Registrants' Consolidated Statements of Financial Position at December 31: DTE Energy DTE Electric 2019 2018 2019 2018 (In millions) Change in accumulated postretirement benefit obligation Accumulated postretirement benefit obligation, beginning of year $ 1,645 $ 1,910 $ 1,247 $ 1,470 Service cost 22 27 16 20 Interest cost 70 69 53 53 Plan amendments (53 ) (44 ) (33 ) (35 ) Actuarial (gain) loss 153 (227 ) 118 (196 ) Benefits paid (86 ) (90 ) (64 ) (65 ) Accumulated postretirement benefit obligation, end of year $ 1,751 $ 1,645 $ 1,337 $ 1,247 Change in plan assets Plan assets at fair value, beginning of year $ 1,689 $ 1,848 $ 1,158 $ 1,272 Actual return on plan assets 215 (75 ) 141 (52 ) Benefits paid (85 ) (84 ) (63 ) (62 ) Plan assets at fair value, end of year $ 1,819 $ 1,689 $ 1,236 $ 1,158 Funded status $ 68 $ 44 $ (101 ) $ (89 ) Amount recorded as: Noncurrent assets $ 69 $ 45 $ 266 $ 189 Current liabilities (1 ) (1 ) — — Noncurrent liabilities — — (367 ) (278 ) $ 68 $ 44 $ (101 ) $ (89 ) Amounts recognized in Accumulated other comprehensive income (loss), pre-tax Net actuarial (gain) loss $ (8 ) $ 1 $ — $ — $ (8 ) $ 1 $ — $ — Amounts recognized in Regulatory assets (a) Net actuarial loss $ 289 $ 257 $ 193 $ 156 Prior service credit (88 ) (44 ) (62 ) (35 ) $ 201 $ 213 $ 131 $ 121 ______________________________________ (a) See Note 10 to the Consolidated Financial Statements, " Regulatory Matters ."
Schedule of Net Benefit Costs	Net other postretirement credit for DTE Electric includes the following components: 2019 2018 2017 (In millions) Service cost $ 16 $ 20 $ 20 Interest cost 53 53 56 Expected return on plan assets (65 ) (98 ) (90 ) Amortization of: Net actuarial loss 5 8 8 Prior service credit (7 ) — (10 ) Net other postretirement cost (credit) $ 2 $ (17 ) $ (16 ) Net other postretirement credit for DTE Energy includes the following components: 2019 2018 2017 (In millions) Service cost $ 22 $ 27 $ 27 Interest cost 70 69 73 Expected return on plan assets (96 ) (143 ) (130 ) Amortization of: Net actuarial loss 12 11 13 Prior service credit (9 ) — (14 ) Net other postretirement credit $ (1 ) $ (36 ) $ (31 )
Schedule of Amounts Recognized in Other Comprehensive Income (Loss)	2019 2018 (In millions) Other changes in plan assets and accumulated postretirement benefit obligation recognized in Regulatory assets Net actuarial (gain) loss $ 41 $ (46 ) Amortization of net actuarial loss (5 ) (8 ) Prior service cost (33 ) — Amortization of prior service (cost) credit 7 (35 ) Total recognized in Regulatory assets $ 10 $ (89 ) Total recognized in net periodic benefit cost and Regulatory assets $ 12 $ (106 ) Estimated amounts to be amortized from Regulatory assets into net periodic benefit cost during next fiscal year Net actuarial loss $ 11 $ 5 Prior service credit $ (14 ) $ (7 ) 2019 2018 (In millions) Other changes in plan assets and accumulated postretirement benefit obligation recognized in Regulatory assets and Other comprehensive income (loss) Net actuarial (gain) loss $ 34 $ (8 ) Amortization of net actuarial loss (12 ) (11 ) Prior service credit (53 ) (44 ) Amortization of prior service credit 9 — Total recognized in Regulatory assets and Other comprehensive income (loss) $ (22 ) $ (63 ) Total recognized in net periodic benefit cost, Regulatory assets, and Other comprehensive income (loss) $ (23 ) $ (99 ) Estimated amounts to be amortized from Regulatory assets and Accumulated other comprehensive income (loss) into net periodic benefit cost during next fiscal year Net actuarial loss $ 16 $ 12 Prior service credit $ (19 ) $ (9 )
Schedule of Expected Benefit Payments	At December 31, 2019 , the benefits expected to be paid, including prescription drug benefits, in each of the next five years and in the aggregate for the five fiscal years thereafter for the Registrants are as follows: DTE Energy DTE Electric (In millions) 2020 $ 84 $ 64 2021 88 67 2022 92 70 2023 94 72 2024 96 73 2025-2029 496 378 Total $ 950 $ 724
Schedule of Assumptions Used	Assumptions used in determining the accumulated postretirement benefit obligation and net other postretirement benefit costs of the Registrants are: 2019 2018 2017 Accumulated postretirement benefit obligation Discount rate 3.29% 4.40% 3.70% Health care trend rate pre- and post- 65 6.75 / 7.25% 6.75 / 7.25% 6.75 / 7.25% Ultimate health care trend rate 4.50% 4.50% 4.50% Year in which ultimate reached pre- and post- 65 2032 2031 2030 Other postretirement benefit costs Discount rate 4.40% 3.70% 4.25% Expected long-term rate of return on plan assets 7.30% 7.75% 7.75% Health care trend rate pre- and post- 65 6.75 / 7.25% 6.75 / 7.25% 6.50 / 6.75% Ultimate health care trend rate 4.50% 4.50% 4.50% Year in which ultimate reached pre- and post- 65 2031 2030 2028
Schedule of Allocation of Plan Assets	Target allocations for the Registrants' other postretirement benefit plan assets as of December 31, 2019 are listed below: U.S. Large Cap Equity Securities 16 % U.S. Small Cap and Mid Cap Equity Securities 3 Non-U.S. Equity Securities 16 Fixed Income Securities 37 Hedge Funds and Similar Investments 14 Private Equity and Other 14 100 % The following tables provide the fair value measurement amounts for the Registrants' other postretirement benefit plan assets at December 31, 2019 and 2018 (a) : December 31, 2019 December 31, 2018 Level 1 Level 2 Other (b) Total Level 1 Level 2 Other (b) Total DTE Energy asset category: (In millions) Short-term Investments (c) $ 80 $ — $ — $ 80 $ 14 $ 2 $ — $ 16 Equity Securities Domestic (d) 51 — 273 324 300 — — 300 International (e) 182 — 89 271 234 — 67 301 Fixed Income Securities Governmental (f) 74 — — 74 — 85 — 85 Corporate (g) — 256 251 507 11 265 130 406 Hedge Funds and Similar Investments (h) 71 — 182 253 97 — 203 300 Private Equity and Other (i) — — 310 310 — — 281 281 DTE Energy Total $ 458 $ 256 $ 1,105 $ 1,819 $ 656 $ 352 $ 681 $ 1,689 DTE Electric asset category: Short-term Investments (c) $ 55 $ — $ — $ 55 $ 10 $ 1 $ — $ 11 Equity Securities Domestic (d) 34 — 185 219 206 — — 206 International (e) 124 — 60 184 163 — 45 208 Fixed Income Securities Governmental (f) 48 — — 48 — 53 — 53 Corporate (g) — 168 176 344 7 179 92 278 Hedge Funds and Similar Investments (h) 49 — 123 172 68 — 139 207 Private Equity and Other (i) — — 214 214 — — 195 195 DTE Electric Total $ 310 $ 168 $ 758 $ 1,236 $ 454 $ 233 $ 471 $ 1,158 _______________________________________ (a) For a description of levels within the fair value hierarchy see Note 13 to the Consolidated Financial Statements, " Fair Value ." (b) Amounts represent assets valued at NAV as a practical expedient for fair value. (c) This category predominantly represents certain short-term fixed income securities and money market investments that are managed in separate accounts or commingled funds. Pricing for investments in this category are obtained from quoted prices in actively traded markets or valuations from brokers or pricing services. (d) This category represents portfolios of large, medium and small capitalization domestic equities. Investments in this category include exchange-traded securities for which unadjusted quoted prices can be obtained and exchange-traded securities held in a commingled fund classified as NAV assets. (e) This category primarily consists of portfolios of non-U.S. developed and emerging market equities. Investments in this category are exchange-traded securities whereby unadjusted quoted prices can be obtained. Exchange-traded securities held in a commingled fund are classified as NAV assets. (f) This category includes U.S. Treasuries, bonds and other governmental debt. Pricing for investments in this category is obtained from quoted prices in actively traded markets and quotations from broker or pricing services. (g) This category primarily consists of corporate bonds from diversified industries, bank loans, and mortgage backed securities. Pricing for investments in this category is obtained from quoted prices in actively traded markets and quotations from broker or pricing services. Non-exchange traded securities and exchange-traded securities held in commingled funds are classified as NAV assets. (h) This category utilizes a diversified group of strategies that attempt to capture financial market inefficiencies and includes publicly traded mutual funds, commingled funds and limited partnership funds. Pricing for mutual funds in this category is obtained from quoted prices in actively traded markets. Commingled funds and limited partnership funds are classified as NAV assets. (i) This category includes a diversified group of funds and strategies that primarily invests in private equity partnerships. This category also includes investments in real estate and private debt. All investments in this category are classified as NAV assets.

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2019
Share-based Payment Arrangement, Noncash Expense [Abstract]
Schedule of Components of Stock-Based Compensation	The following table summarizes the components of stock-based compensation for DTE Energy: 2019 2018 2017 (In millions) Stock-based compensation expense $ 71 $ 64 $ 58 Tax benefit $ 13 $ 13 $ 23 Stock-based compensation cost capitalized in Property, plant, and equipment $ 16 $ 11 $ 9
Stock-based Compensation Expense	DTE Energy recorded compensation expense for performance share awards as follows: 2019 2018 2017 (In millions) Compensation expense $ 60 $ 53 $ 47 Cash settlements (a) $ 19 $ 13 $ 15 Stock settlements (a) $ 79 $ 39 $ 66 _______________________________________ (a) Sum of cash and stock settlements approximates the intrinsic value of the awards.
Schedule of Stock-based Compensation, Performance Shares Activity Rollforward	The following table summarizes DTE Energy’s performance share activity for the period ended December 31, 2019 : Performance Shares Weighted Average Balance at December 31, 2018 1,286,686 $ 97.17 Grants 446,579 $ 115.85 Forfeitures (44,044 ) $ 102.42 Payouts (463,190 ) $ 88.53 Balance at December 31, 2019 1,226,031 $ 107.35
Schedule of Unrecognized Compensation Cost, Non-Vested Awards	As of December 31, 2019 , DTE Energy's total unrecognized compensation cost related to non-vested stock incentive plan arrangements and the weighted average recognition period was as follows: Unrecognized Weighted Average (In millions) (In years) Stock awards $ 19 1.57 Performance shares 62 1.05 $ 81 1.17

Segment and Related Informati_2

Segment and Related Information (Tables)	12 Months Ended
	Dec. 31, 2019
Segment Reporting [Abstract]
Financial Data of Business Segments	Inter-segment billing for goods and services exchanged between segments is based upon tariffed or market-based prices of the provider and primarily consists of the sale of reduced emissions fuel, power sales, and natural gas sales in the following segments: Year Ended December 31, 2019 2018 2017 (In millions) Electric $ 56 $ 52 $ 48 Gas 12 12 8 Gas Storage and Pipelines 27 36 42 Power and Industrial Projects 596 642 569 Energy Trading 22 27 35 Corporate and Other 2 2 2 $ 715 $ 771 $ 704 Financial data of DTE Energy's business segments follows: Electric Gas Gas Storage and Pipelines Power and Industrial Projects Energy Trading Corporate and Other Reclassifications Total (In millions) 2019 Operating Revenues — Utility operations $ 5,224 1,482 — — — — (68 ) $ 6,638 Operating Revenues — Non-utility operations $ 5 — 501 1,560 4,610 2 (647 ) $ 6,031 Depreciation and amortization $ 949 144 94 69 6 1 — $ 1,263 Interest expense $ 315 78 73 33 8 266 (132 ) $ 641 Interest income $ (2 ) (6 ) (8 ) (9 ) (4 ) (120 ) 132 $ (17 ) Equity in earnings of equity method investees $ 1 2 97 14 — (3 ) — $ 111 Income Tax Expense (Benefit) $ 137 62 74 (63 ) 17 (75 ) — $ 152 Net Income (Loss) Attributable to DTE Energy Company $ 714 185 204 133 49 (116 ) — $ 1,169 Investment in equity method investees $ 5 11 1,685 130 — 31 — $ 1,862 Capital expenditures and acquisitions $ 2,368 530 2,510 54 5 — — $ 5,467 Goodwill $ 1,208 743 470 26 17 — — $ 2,464 Total Assets $ 24,617 5,717 4,832 537 798 7,679 (2,298 ) $ 41,882 Electric Gas Gas Storage and Pipelines Power and Industrial Projects Energy Trading Corporate and Other Reclassifications Total (In millions) 2018 Operating Revenues — Utility operations $ 5,298 1,436 — — — — (64 ) $ 6,670 Operating Revenues — Non-utility operations $ — 485 2,204 5,557 3 (707 ) $ 7,542 Depreciation and amortization $ 836 133 82 67 5 1 — $ 1,124 Interest expense $ 283 70 68 31 6 220 (119 ) $ 559 Interest income $ — (6 ) (9 ) (9 ) (3 ) (104 ) 119 $ (12 ) Equity in earnings of equity method investees $ — 2 123 3 — 4 — $ 132 Income Tax Expense (Benefit) $ 193 67 68 (195 ) 13 (48 ) — $ 98 Net Income (Loss) Attributable to DTE Energy Company $ 664 150 235 161 39 (129 ) — $ 1,120 Investment in equity method investees $ 7 12 1,585 134 — 33 — $ 1,771 Capital expenditures and acquisitions $ 1,979 460 176 91 5 2 — $ 2,713 Goodwill $ 1,208 743 299 26 17 — — $ 2,293 Total Assets $ 22,501 5,378 3,161 495 909 6,153 (2,309 ) $ 36,288 Electric Gas Gas Storage and Pipelines Power and Industrial Projects Energy Trading Corporate and Other Reclassifications Total (In millions) 2017 Operating Revenues — Utility operations $ 5,102 1,388 — — — — (56 ) $ 6,434 Operating Revenues — Non-utility operations $ — — 453 2,089 4,277 2 (648 ) $ 6,173 Depreciation and amortization $ 753 123 76 72 5 1 — $ 1,030 Interest expense $ 274 65 77 29 5 192 (106 ) $ 536 Interest income $ — (7 ) (14 ) (7 ) (2 ) (88 ) 106 $ (12 ) Equity in earnings of equity method investees $ 1 2 90 9 — — — $ 102 Income Tax Expense (Benefit) (a) $ 321 78 (30 ) (195 ) 49 (48 ) — $ 175 Net Income (Loss) Attributable to DTE Energy Company $ 606 146 275 138 72 (103 ) — $ 1,134 Investment in equity method investees $ 7 11 879 150 — 26 — $ 1,073 Capital expenditures and acquisitions $ 1,574 463 137 56 7 13 — $ 2,250 Goodwill $ 1,208 743 299 26 17 — — $ 2,293 Total Assets $ 21,163 5,072 2,594 593 725 5,324 (1,704 ) $ 33,767 _____________________________________ (a) Includes Income Tax Expense (Benefit) of $(5) million , $(115) million , $(21) million , $2 million , and $34 million for Electric — non-utility, Gas Storage and Pipelines, Power and Industrial Projects, Energy Trading, and Corporate and Other, respectively, related to the enactment of the TCJA.

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2019
Related Party Transactions [Abstract]
Transactions With Affiliated Companies	The following is a summary of DTE Electric's transactions with affiliated companies: 2019 2018 2017 (In millions) Revenues Energy sales $ 10 $ 9 $ 9 Other services $ 5 $ 4 $ 4 Shared capital assets $ 47 $ 43 $ 39 Costs Fuel and purchased power $ 9 $ 7 $ 6 Other services and interest $ 23 $ 33 $ (2 ) Corporate expenses, net $ 372 $ 377 $ 370 Other Dividends declared $ 494 $ 461 $ 432 Dividends paid $ 494 $ 461 $ 432 Capital contribution from DTE Energy $ 180 $ 325 $ 100 See the following notes for other related party transactions impacting DTE Electric’s Consolidated Financial Statements: Note Title 1 Organization and Basis of Presentation 21 Retirement Benefits and Trusteed Assets 22 Stock-Based Compensation

Supplementary Quarterly Finan_2

Supplementary Quarterly Financial Information (Unaudited ) (Tables)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information	DTE Energy Quarterly earnings per share may not equal full year totals, since quarterly computations are based on weighted average common shares outstanding during each quarter. First Second Third Fourth Year (In millions, except per share amounts) 2019 Operating Revenues $ 3,514 $ 2,888 $ 3,119 $ 3,148 $ 12,669 Operating Income $ 542 $ 300 $ 450 $ 415 $ 1,707 Net Income Attributable to DTE Energy Company $ 401 $ 182 $ 319 $ 267 $ 1,169 Basic Earnings per Share $ 2.20 $ 0.99 $ 1.74 $ 1.40 $ 6.32 Diluted Earnings per Share $ 2.19 $ 0.99 $ 1.73 $ 1.40 $ 6.31 2018 Operating Revenues $ 3,753 $ 3,159 $ 3,550 $ 3,750 $ 14,212 Operating Income $ 504 $ 329 $ 429 $ 332 $ 1,594 Net Income Attributable to DTE Energy Company $ 361 $ 234 $ 334 $ 191 $ 1,120 Basic Earnings per Share $ 2.01 $ 1.29 $ 1.84 $ 1.05 $ 6.18 Diluted Earnings per Share $ 2.00 $ 1.29 $ 1.84 $ 1.05 $ 6.17 DTE Electric First Second Third Fourth Year (In millions) 2019 Operating Revenues $ 1,235 $ 1,190 $ 1,519 $ 1,280 $ 5,224 Operating Income $ 226 $ 223 $ 440 $ 224 $ 1,113 Net Income $ 147 $ 133 $ 307 $ 129 $ 716 2018 Operating Revenues $ 1,205 $ 1,276 $ 1,521 $ 1,296 $ 5,298 Operating Income $ 253 $ 269 $ 444 $ 168 $ 1,134 Net Income $ 140 $ 163 $ 305 $ 56 $ 664

Organization and Basis of Pre_3

Organization and Basis of Presentation (Details) customer in Millions	Dec. 31, 2019USD ($)customer	Dec. 31, 2018USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of electric utility customers | customer	2.2
Number of gas utility customers | customer	1.3
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Material potential exposure	$ 0
Amount in excess of carrying amount	74,000,000	$ 59,000,000
DTE Electric
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Material potential exposure	$ 0
NEXUS Pipeline
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Ownership interest	50.00%
SGG | Midstream Natural Gas Assets
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Percentage of voting interests acquired	85.00%

Organization and Basis of Pre_4

Organization and Basis of Presentation (Consolidated Variable Interest Entities) (Details) - USD ($) $ in Millions	8 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
ASSETS
Cash and cash equivalents	$ 93	$ 93	$ 71
Restricted cash	0	0	5
Accounts receivable	1,642	1,642	1,789
Property, plant, and equipment, net	25,317	25,317	21,650
Goodwill	2,464	2,464	2,293	$ 2,293
Intangible assets	2,378	2,378	828
Total Assets	41,882	41,882	36,288	$ 33,767
Variable interest entity, primary beneficiary, restricted
ASSETS
Cash and cash equivalents	27	27	39
Restricted cash	0	0	5
Accounts receivable	27	27	46
Inventories	74	74	93
Property, plant, and equipment, net	443	443	441
Goodwill	25	25	25
Intangible assets	542	542	557
Other current and long-term assets	2	2	3
Total Assets	1,140	1,140	1,209
LIABILITIES
Accounts payable and accrued current liabilities	15	15	34
Other current and long-term liabilities	14	14	19
Total liabilities	29	29	53
SGG
ASSETS
Cash and cash equivalents	16	16	25
Restricted cash	0	0	0
Accounts receivable	8	8	9
Inventories	0	0	1
Property, plant, and equipment, net	410	410	395
Goodwill	25	25	25
Intangible assets	542	542	557
Other current and long-term assets	2	2	3
Total Assets	1,003	1,003	1,015
LIABILITIES
Accounts payable and accrued current liabilities	2	2	3
Other current and long-term liabilities	7	7	9
Total liabilities	$ 9	$ 9	$ 12
VIE ownership and non-ownership percentage		100.00%
VIE ownership percentage	85.00%		55.00%
Other
ASSETS
Cash and cash equivalents	$ 11	$ 11	$ 14
Restricted cash	0	0	5
Accounts receivable	19	19	37
Inventories	74	74	92
Property, plant, and equipment, net	33	33	46
Goodwill	0	0	0
Intangible assets	0	0	0
Other current and long-term assets	0	0	0
Total Assets	137	137	194
LIABILITIES
Accounts payable and accrued current liabilities	13	13	31
Other current and long-term liabilities	7	7	10
Total liabilities	$ 20	$ 20	$ 41

Organization and Basis of Pre_5

Organization and Basis of Presentation (Non-Consolidated Variable Interest Entities) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Variable Interest Entity [Line Items]
Investments in equity method investees	$ 1,862	$ 1,771	$ 1,073
Notes receivable	202	64
Variable interest entity, nonconsolidated
Variable Interest Entity [Line Items]
Investments in equity method investees	1,503	1,425
Notes receivable	21	15
Future funding commitments	$ 63	$ 55

Organization and Basis of Pre_6

Organization and Basis of Presentation (Equity Method Investees) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Investments	$ 1,862	$ 1,771	$ 1,073
NEXUS Pipeline
Schedule of Equity Method Investments [Line Items]
Percent Owned	50.00%
Gas Storage and Pipelines
Schedule of Equity Method Investments [Line Items]
Investments	$ 1,685	1,585
Gas Storage and Pipelines | NEXUS Pipeline
Schedule of Equity Method Investments [Line Items]
Investments	$ 1,345	$ 1,260
Percent Owned	50.00%	50.00%
Gas Storage and Pipelines | Vector Pipeline
Schedule of Equity Method Investments [Line Items]
Investments	$ 131	$ 123
Percent Owned	40.00%	40.00%
Gas Storage and Pipelines | Millennium Pipeline
Schedule of Equity Method Investments [Line Items]
Investments	$ 209	$ 202
Percent Owned	26.00%	26.00%
Other Segments
Schedule of Equity Method Investments [Line Items]
Investments	$ 177	$ 186

Organization and Basis of Pre_7

Organization and Basis of Presentation (Summarized Balance Sheet Data) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Current Assets	$ 374	$ 358
Non-current assets	5,260	5,101
Current Liabilities	414	391
Non-current liabilities	$ 698	$ 762

Organization and Basis of Pre_8

Organization and Basis of Presentation (Summarized Income Statement Data) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Operating Revenues	$ 1,210	$ 883	$ 756
Operating Expenses	853	622	561
Net Income	$ 313	$ 365	$ 254

Significant Accounting Polici_4

Significant Accounting Policies (Schedule of Other Income) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule of Other Nonoperating Income, by Component [Line Items]
Income from REF entities	$ 130	$ 98	$ 77
Equity in earnings of equity method investees	111	132	102
Gains from equity securities	37	6	26
Contract services	29	51	19
Allowance for equity funds used during construction	24	28	23
Other	19	18	21
Other income	350	333	268
DTE Electric
Schedule of Other Nonoperating Income, by Component [Line Items]
Gains from equity securities	37	6	26
Contract services	32	51	21
Allowance for equity funds used during construction	22	19	18
Other	16	7	12
Other income	$ 107	$ 83	$ 77

Significant Accounting Polici_5

Significant Accounting Policies (Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2019	Jan. 01, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	$ 10,717	$ 9,990	$ 9,499
Net current-period Other comprehensive income (loss)	(3)	5	13
Ending balance	11,836	10,717	9,990
ASU 2016-01
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Implementation of ASU					$ 0
ASU 2018-02
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Implementation of ASU				$ 0
AOCI including portion attributable to noncontrolling interest
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(120)	(120)
Other comprehensive income (loss) before reclassifications	(20)	(5)
Amounts reclassified from Accumulated other comprehensive income (loss)	17	10
Net current-period Other comprehensive income (loss)	(3)	5
Ending balance	(148)	(120)	(120)
AOCI including portion attributable to noncontrolling interest | ASU 2016-01
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Implementation of ASU					(5)
AOCI including portion attributable to noncontrolling interest | ASU 2018-02
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Implementation of ASU				(25)
Net Unrealized Gain (Loss) on Derivatives
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(11)	(3)
Other comprehensive income (loss) before reclassifications	(14)	(2)
Amounts reclassified from Accumulated other comprehensive income (loss)	2	1
Net current-period Other comprehensive income (loss)	(12)	(1)
Ending balance	(25)	(11)	(3)
Net Unrealized Gain (Loss) on Derivatives | ASU 2016-01
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Implementation of ASU					(7)
Net Unrealized Gain (Loss) on Derivatives | ASU 2018-02
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Implementation of ASU				(2)
Net Unrealized Loss on Investments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	0	(2)
Other comprehensive income (loss) before reclassifications	0	0
Amounts reclassified from Accumulated other comprehensive income (loss)	0	0
Net current-period Other comprehensive income (loss)	0	0
Ending balance	0	0	(2)
Net Unrealized Loss on Investments | ASU 2016-01
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Implementation of ASU					2
Net Unrealized Loss on Investments | ASU 2018-02
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Implementation of ASU				0
Benefit Obligations
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(102)	(110)
Other comprehensive income (loss) before reclassifications	(7)	(1)
Amounts reclassified from Accumulated other comprehensive income (loss)	15	9
Net current-period Other comprehensive income (loss)	8	8
Ending balance	(117)	(102)	(110)
Benefit Obligations | ASU 2016-01
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Implementation of ASU					0
Benefit Obligations | ASU 2018-02
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Implementation of ASU				(23)
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(7)	(5)
Other comprehensive income (loss) before reclassifications	1	(2)
Amounts reclassified from Accumulated other comprehensive income (loss)	0	0
Net current-period Other comprehensive income (loss)	1	(2)
Ending balance	$ (6)	$ (7)	$ (5)
Foreign Currency Translation | ASU 2016-01
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Implementation of ASU					$ 0
Foreign Currency Translation | ASU 2018-02
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Implementation of ASU				$ 0

Significant Accounting Polici_6

Significant Accounting Policies (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Significant Accounting Policies [Line Items]
Specific review of probable future collections based on receivable balances in excess of 90 days	30 days
Unbilled revenues	$ 1,642,000,000	$ 1,789,000,000
Intangible assets	33,000,000	27,000,000	$ 29,000,000
Excise and sales taxes net impact on statement of operations	0
Charitable contributions	0	22,000,000	$ 43,000,000
Natural gas inventory
Significant Accounting Policies [Line Items]
LIFO inventory amount	40,000,000	48,000,000
Excess of replacement costs over stated LIFO value	$ 49,000,000	113,000,000
Minimum
Significant Accounting Policies [Line Items]
Notes receivable considered delinquent period	60 days
Maximum
Significant Accounting Policies [Line Items]
Notes receivable considered delinquent period	120 days
DTE Electric and DTE Gas
Significant Accounting Policies [Line Items]
Receivables due date	21 days
Threshold period past due for write-off of trade accounts receivable	150 days
DTE Electric
Significant Accounting Policies [Line Items]
Unbilled revenues	$ 729,000,000	750,000,000
Unbilled revenues
Significant Accounting Policies [Line Items]
Unbilled revenues	900,000,000	1,000,000,000
Unbilled revenues | DTE Electric
Significant Accounting Policies [Line Items]
Unbilled revenues	$ 263,000,000	$ 264,000,000

Significant Accounting Polici_7

Significant Accounting Policies (Intangible Assets) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying value	$ 2,520	$ 938
Accumulated Amortization	(142)	(110)
Finite-lived intangible assets, net carrying value	2,378	828
Intangible assets, gross carrying value	2,535	959
Intangible assets, net carrying value	2,393	849
DTE Electric
Finite-Lived Intangible Assets [Line Items]
Intangible assets, net carrying value	15	21
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets	15	21
DTE Electric renewable energy credits | DTE Electric
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets	15	20
DTE Electric emission allowances | DTE Electric
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets	0	1
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying value	2,252	779
Accumulated Amortization	(66)	(44)
Finite-lived intangible assets, net carrying value	$ 2,186	735
Customer relationships | Minimum
Finite-Lived Intangible Assets [Line Items]
Useful Lives	25 years
Customer relationships | Maximum
Finite-Lived Intangible Assets [Line Items]
Useful Lives	40 years
Contract intangibles
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying value	$ 268	159
Accumulated Amortization	(76)	(66)
Finite-lived intangible assets, net carrying value	$ 192	$ 93
Contract intangibles | Minimum
Finite-Lived Intangible Assets [Line Items]
Useful Lives	6 years
Contract intangibles | Maximum
Finite-Lived Intangible Assets [Line Items]
Useful Lives	26 years

Significant Accounting Polici_8

Significant Accounting Policies (Future Amortization Expense Intangible Assets) (Details) $ in Millions	Dec. 31, 2019USD ($)
Estimated amortization expense
2020	$ 82
2021	86
2022	86
2023	86
2024	$ 86

New Accounting Pronouncements

New Accounting Pronouncements (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets	$ 169
Lease liabilities for certain operating leases	160
DTE Electric
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets	87
Lease liabilities for certain operating leases	$ 79
Accounting Standards Update 2018-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets		$ 137
Lease liabilities for certain operating leases		130
Prepaid lease costs reclassified from Other assets, current and noncurrent		9
Prepaid lease costs reclassified from Other liabilities, current and noncurrent		2
Accounting Standards Update 2018-02 | DTE Electric
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets		74
Lease liabilities for certain operating leases		67
Accounting Standards Update 2018-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of income tax effects		0
Accumulated Other Comprehensive Income (Loss) | Accounting Standards Update 2018-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of income tax effects		(25)
Retained Earnings | Accounting Standards Update 2018-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of income tax effects		$ 25

Acquisitions (Details Textuals)

Acquisitions (Details Textuals) $ in Millions	Dec. 04, 2019USD ($)	Sep. 20, 2019USD ($)	Sep. 12, 2019USD ($)MW	Jan. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)
Business Acquisition [Line Items]
Liability for contingent consideration payment and related accretion expense					$ 379	$ 379	$ 0
Goodwill					2,464	2,464	2,293	$ 2,293
Operating Revenues — Non-utility operations						6,031	7,542	6,173
Net Income						1,172	$ 1,118	$ 1,112
Gas Storage and Pipelines | Generation Pipeline, LLC
Business Acquisition [Line Items]
Portion of consideration paid attributable to DTE Energy		50.00%
Gas Storage and Pipelines | Blue Union and LEAP
Business Acquisition [Line Items]
Total consideration provided for acquired entity	$ 2,740
Consideration paid for entity acquired, paid in cash	$ 2,360
Percent of assets acquired	100.00%
Contingent consideration to be paid upon completion	$ 378
Contingent payment, low end of range	0
Contingent payment, high end of range	385
Liability for contingent consideration payment and related accretion expense					1	1
Cash consideration paid and held in escrow	100
Goodwill	$ 171
Direct transaction costs incurred					18	18
Issuance costs related to acquisition financing					49	49
Operating Revenues — Non-utility operations					15
Net Income					3
Gas Storage and Pipelines | Blue Union and LEAP | Other long-term debt
Business Acquisition [Line Items]
Issuance costs related to acquisition financing					10	10
Gas Storage and Pipelines | Blue Union and LEAP | Common Stock
Business Acquisition [Line Items]
Issuance costs related to acquisition financing					$ 39	$ 39
Contract intangibles | Minimum
Business Acquisition [Line Items]
Intangible assets, amortization period						6 years
Contract intangibles | Maximum
Business Acquisition [Line Items]
Intangible assets, amortization period						26 years
Customer relationships | Minimum
Business Acquisition [Line Items]
Intangible assets, amortization period						25 years
Customer relationships | Maximum
Business Acquisition [Line Items]
Intangible assets, amortization period						40 years
Customer relationships | Gas Storage and Pipelines | Blue Union and LEAP
Business Acquisition [Line Items]
Intangible assets, amortization period	40 years
Intangible assets recorded as a result of acquisition	$ 1,473
Existing intangible asset weighted-average amortization life	13 years
DTE Sustainable Generation | Electric | Heritage Sustainable Energy, Renewable Energy Project
Business Acquisition [Line Items]
Amount of power associated with purchase of renewable energy project | MW			89
Total consideration provided for acquired entity			$ 175
Consideration paid for entity acquired, paid in cash			174
DTE Sustainable Generation | Contract intangibles | Electric | Heritage Sustainable Energy, Renewable Energy Project
Business Acquisition [Line Items]
Intangible assets recorded as a result of acquisition			$ 109
DTE Sustainable Generation | Contract intangibles | Electric | Heritage Sustainable Energy, Renewable Energy Project | Minimum
Business Acquisition [Line Items]
Intangible assets, amortization period			11 years
DTE Sustainable Generation | Contract intangibles | Electric | Heritage Sustainable Energy, Renewable Energy Project | Maximum
Business Acquisition [Line Items]
Intangible assets, amortization period			13 years
DTE Sustainable Generation | Subsequent Event | Electric | Heritage Sustainable Energy, Additional Renewable Energy Project
Business Acquisition [Line Items]
Consideration paid for entity acquired, paid in cash				$ 33
NEXUS | Gas Storage and Pipelines | Generation Pipeline, LLC
Business Acquisition [Line Items]
Total consideration provided for acquired entity		$ 163

Acquisitions (Purchase Price Al

Acquisitions (Purchase Price Allocation - Electric Segment Acquisition) (Details) - DTE Sustainable Generation - Electric - Heritage Sustainable Energy, Renewable Energy Project $ in Millions	Sep. 12, 2019USD ($)
Business Acquisition [Line Items]
Property, plant, and equipment, net	$ 60
Working capital	6
Total	175
Contract intangibles
Business Acquisition [Line Items]
Contract intangibles	$ 109

Acquisitions (Purchase Price _2

Acquisitions (Purchase Price Allocation - Gas Storage and Pipelines Segment Acquisition) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 04, 2019	Dec. 31, 2018	Dec. 31, 2017
Assets
Goodwill	$ 2,464		$ 2,293	$ 2,293
Gas Storage and Pipelines | Blue Union and LEAP
Assets
Cash		$ 62
Accounts receivable		31
Property, plant, and equipment, net		1,035
Goodwill		171
Other current assets		1
Total assets		2,773
Liabilities
Accounts payable		26
Acquisition related deferred payment		378
Other current liabilities		2
Asset retirement obligations		9
Total liabilities		415
Total cash consideration		2,358
Gas Storage and Pipelines | Customer relationships | Blue Union and LEAP
Assets
Customer relationship intangibles		$ 1,473

Revenue (Disaggregation of Reve

Revenue (Disaggregation of Revenue) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Revenues	$ 3,148	$ 3,119	$ 2,888	$ 3,514	$ 3,750	$ 3,550	$ 3,159	$ 3,753	$ 12,669	$ 14,212	$ 12,607
Lease revenue outside scope of Topic 606									193
Electric
Disaggregation of Revenue [Line Items]
Revenues									5,229	5,298
Electric | Alternative Revenue Programs
Disaggregation of Revenue [Line Items]
Revenues									22	21
Electric | Other
Disaggregation of Revenue [Line Items]
Revenues									19	20
Electric | Residential
Disaggregation of Revenue [Line Items]
Revenues									2,427	2,494
Electric | Commercial
Disaggregation of Revenue [Line Items]
Revenues									1,795	1,794
Electric | Industrial
Disaggregation of Revenue [Line Items]
Revenues									659	690
Electric | Other
Disaggregation of Revenue [Line Items]
Revenues									348	320
Gas
Disaggregation of Revenue [Line Items]
Revenues									1,482	1,436
Gas | Alternative Revenue Programs
Disaggregation of Revenue [Line Items]
Revenues									8	2
Gas | Other
Disaggregation of Revenue [Line Items]
Revenues									7	7
Gas | Other
Disaggregation of Revenue [Line Items]
Revenues									142	91
Gas | Gas sales
Disaggregation of Revenue [Line Items]
Revenues									1,043	1,055
Gas | End User Transportation
Disaggregation of Revenue [Line Items]
Revenues									219	232
Gas | Intermediate Transportation
Disaggregation of Revenue [Line Items]
Revenues									78	58
Gas Storage and Pipelines
Disaggregation of Revenue [Line Items]
Revenues									501	485
Lease revenue outside scope of Topic 606									9
Power and Industrial Projects
Disaggregation of Revenue [Line Items]
Revenues									1,560	2,204
Lease revenue outside scope of Topic 606									121
Lease revenue outside scope of Topic 606										125
Energy Trading
Disaggregation of Revenue [Line Items]
Revenues									4,610	5,557
Gain (loss) on derivative outside scope of Topic 606									$ 3,400	$ 4,500

Revenue (Narrative) (Details)

Revenue (Narrative) (Details)	12 Months Ended
	Dec. 31, 2019
Other | Power and Industrial Projects
Revenue from External Customer [Line Items]
Payment terms	30 days

Revenue (Deferred Revenue) (Det

Revenue (Deferred Revenue) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)
Contract Liability [Roll Forward]
Beginning Balance	$ 74
Increases due to cash received or receivable, excluding amounts recognized as revenue during the period	51
Revenue recognized that was included in the deferred revenue balance at the beginning of the period	(50)
Ending Balance	$ 75

Revenue (Expected Recognition o

Revenue (Expected Recognition of Deferred Revenue) (Details) $ in Millions	Dec. 31, 2019USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 43
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 6
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 7
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 6
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 3
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 10
Remaining performance obligation, expected timing of satisfaction
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 75

Revenue (Expected Timing of Per

Revenue (Expected Timing of Performance Obligation Satisfaction) (Details) $ in Millions	Dec. 31, 2019USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 43
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01 | Fixed Consideration
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 253
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01 | Fixed Consideration | DTE Electric
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 8
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 6
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01 | Fixed Consideration
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 292
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01 | Fixed Consideration | DTE Electric
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 8
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 7
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01 | Fixed Consideration
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 232
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01 | Fixed Consideration | DTE Electric
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 7
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 6
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01 | Fixed Consideration
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 164
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01 | Fixed Consideration | DTE Electric
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 7
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 3
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01 | Fixed Consideration
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 126
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01 | Fixed Consideration | DTE Electric
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 7
Remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 10
Remaining performance obligation, expected timing of satisfaction
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 | Fixed Consideration
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 538
Remaining performance obligation, expected timing of satisfaction
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 | Fixed Consideration | DTE Electric
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 0
Remaining performance obligation, expected timing of satisfaction
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 75
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil) | Fixed Consideration
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	1,605
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil) | Fixed Consideration | DTE Electric
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 37

Revenue (Expenses Recognized fo

Revenue (Expenses Recognized for Estimated Uncollectible Accounts Receivable) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Revenue from External Customer [Line Items]
Expenses recognized for estimated uncollectible accounts receivable	$ 111	$ 140
DTE Electric
Revenue from External Customer [Line Items]
Expenses recognized for estimated uncollectible accounts receivable	$ 65	$ 85

Goodwill (Details)

Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Balance as of January 1	$ 2,293	$ 2,293
Goodwill attributable to Gas Storage and Pipelines 2019 acquisition of Blue Union and LEAP	171	0
Balance at December 31	$ 2,464	$ 2,293

Property, Plant, and Equipmen_2

Property, Plant, and Equipment (Summary of Property by Classification) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Property, Plant, and Equipment [Line Items]
Property, plant, and equipment	$ 35,072	$ 31,810
Accumulated depreciation and amortization	(9,755)	(10,160)
Net property, plant, and equipment	25,317	21,650
Gas Storage and Pipelines
Property, Plant, and Equipment [Line Items]
Property, plant, and equipment	3,524	2,307
Accumulated depreciation and amortization	(459)	(390)
Power and Industrial Projects
Property, Plant, and Equipment [Line Items]
Property, plant, and equipment	1,108	1,070
Accumulated depreciation and amortization	(604)	(546)
Other
Property, Plant, and Equipment [Line Items]
Property, plant, and equipment	183	111
Accumulated depreciation and amortization	(71)	(62)
Non-utility and other
Property, Plant, and Equipment [Line Items]
Property, plant, and equipment	4,815	3,488
Accumulated depreciation and amortization	(1,134)	(998)
DTE Electric
Property, Plant, and Equipment [Line Items]
Property, plant, and equipment	24,279	22,747
Accumulated depreciation and amortization	(6,706)	(7,310)
Net property, plant, and equipment	17,573	15,437
DTE Electric | Generation
Property, Plant, and Equipment [Line Items]
Property, plant, and equipment	12,028	11,027
Accumulated depreciation and amortization	(3,460)	(3,609)
DTE Electric | Distribution
Property, Plant, and Equipment [Line Items]
Property, plant, and equipment	9,715	9,153
Accumulated depreciation and amortization	(2,553)	(2,974)
DTE Electric | Other
Property, Plant, and Equipment [Line Items]
Property, plant, and equipment	2,536	2,567
Accumulated depreciation and amortization	(693)	(727)
DTE Gas
Property, Plant, and Equipment [Line Items]
Property, plant, and equipment	5,978	5,575
Accumulated depreciation and amortization	(1,915)	(1,852)
DTE Gas | Distribution
Property, Plant, and Equipment [Line Items]
Property, plant, and equipment	4,164	3,823
Accumulated depreciation and amortization	(1,334)	(1,283)
DTE Gas | Storage
Property, Plant, and Equipment [Line Items]
Property, plant, and equipment	570	548
Accumulated depreciation and amortization	(172)	(165)
DTE Gas | Transmission and other
Property, Plant, and Equipment [Line Items]
Property, plant, and equipment	1,244	1,204
Accumulated depreciation and amortization	$ (409)	$ (404)

Property, Plant, and Equipmen_3

Property, Plant, and Equipment (Schedule of Interest Costs Capitalized) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Property, Plant, and Equipment [Line Items]
Allowance for debt funds used during construction and interest capitalized	$ 15	$ 15
Allowance for equity funds used during construction	24	28
Total	39	43
DTE Electric
Property, Plant, and Equipment [Line Items]
Allowance for debt funds used during construction and interest capitalized	10	9
Allowance for equity funds used during construction	22	19
Total	$ 32	$ 28

Property, Plant, and Equipmen_4

Property, Plant, and Equipment (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Minimum | Non-utility
Public Utility Property, Plant, and Equipment [Line Items]
Property plant and equipment, useful life	2 years
Minimum | Capitalized software
Public Utility Property, Plant, and Equipment [Line Items]
Property plant and equipment, useful life	3 years
Maximum | Non-utility
Public Utility Property, Plant, and Equipment [Line Items]
Property plant and equipment, useful life	55 years
Maximum | Capitalized software
Public Utility Property, Plant, and Equipment [Line Items]
Property plant and equipment, useful life	15 years
DTE Electric | Minimum | Other
Public Utility Property, Plant, and Equipment [Line Items]
Property plant and equipment, useful life	3 years
DTE Electric | Minimum | Capitalized software
Public Utility Property, Plant, and Equipment [Line Items]
Property plant and equipment, useful life	3 years
DTE Electric | Maximum | Other
Public Utility Property, Plant, and Equipment [Line Items]
Property plant and equipment, useful life	80 years
DTE Electric | Maximum | Capitalized software
Public Utility Property, Plant, and Equipment [Line Items]
Property plant and equipment, useful life	15 years
DTE Gas | Minimum | Transmission and other
Public Utility Property, Plant, and Equipment [Line Items]
Property plant and equipment, useful life	3 years
DTE Gas | Maximum | Transmission and other
Public Utility Property, Plant, and Equipment [Line Items]
Property plant and equipment, useful life	70 years
DTE Electric
Public Utility Property, Plant, and Equipment [Line Items]
Composite depreciation rate for plants in service	4.00%	3.70%	3.60%
DTE Gas
Public Utility Property, Plant, and Equipment [Line Items]
Composite depreciation rate for plants in service	2.70%	2.70%	2.70%

Property, Plant, and Equipmen_5

Property, Plant, and Equipment (Average Estimated Useful Life of Each Major Class) (Details)	12 Months Ended
	Dec. 31, 2019
DTE Electric
Public Utility Property, Plant, and Equipment [Line Items]
Useful Life - Generation	34 years
Useful Life - Distribution	38 years
DTE Gas
Public Utility Property, Plant, and Equipment [Line Items]
Useful Life - Distribution	50 years
Useful Life - Storage	56 years

Property, Plant, and Equipmen_6

Property, Plant, and Equipment (Depreciation and Amortization) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant, and Equipment [Line Items]
Property, plant, and equipment	$ 997	$ 878	$ 829
Regulatory assets and liabilities	227	212	165
Intangible assets	33	27	29
Other	6	7	7
Depreciation and amortization	1,263	1,124	1,030
DTE Electric
Property, Plant, and Equipment [Line Items]
Property, plant, and equipment	748	652	615
Regulatory assets and liabilities	193	179	133
Other	5	5	5
Depreciation and amortization	$ 946	$ 836	$ 753

Property, Plant, and Equipmen_7

Property, Plant, and Equipment (Capitalized Software) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant, and Equipment [Line Items]
Amortization expense of capitalized software	$ 123	$ 108	$ 101
Gross carrying value of capitalized software	906	905
Accumulated amortization of capitalized software	520	534
DTE Electric
Property, Plant, and Equipment [Line Items]
Amortization expense of capitalized software	112	101	$ 93
Gross carrying value of capitalized software	811	799
Accumulated amortization of capitalized software	$ 462	$ 463

Jointly-Owned Utility Plant (De

Jointly-Owned Utility Plant (Details)	Dec. 31, 2019plant
Belle River Unit 1
Jointly-Owned Utility Plant Interests [Line Items]
Percent of the total capacity and energy of the plant	19.00%
Ludington Hydroelectric Pumped Storage
Jointly-Owned Utility Plant Interests [Line Items]
Percent of the total capacity and energy of the plant	51.00%
DTE Electric
Jointly-Owned Utility Plant Interests [Line Items]
Number of power plants owned	2

Jointly-Owned Utility Plant (Ow

Jointly-Owned Utility Plant (Ownership Information) (Details) - DTE Electric $ in Millions	Dec. 31, 2019USD ($)MW
Belle River
Jointly-Owned Utility Plant Interests [Line Items]
Total plant capacity | MW	1,270
Ownership interest	81.00%
Investment in Property, plant, and equipment (in millions)	$ 1,903
Accumulated depreciation (in millions)	$ 896
Ludington Hydroelectric Pumped Storage
Jointly-Owned Utility Plant Interests [Line Items]
Total plant capacity | MW	2,220
Ownership interest	49.00%
Investment in Property, plant, and equipment (in millions)	$ 616
Accumulated depreciation (in millions)	$ 193

Asset Retirement Obligations (R

Asset Retirement Obligations (Rollforward) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset retirement obligations at January 1	$ 2,469	$ 2,320	$ 2,197
Accretion	149	140	131
Liabilities incurred	20	27	2
Liabilities settled	(17)	(16)	(6)
Revision in estimated cash flows	51	(2)	(4)
Asset retirement obligations at December 31	2,672	2,469	2,320
DTE Electric
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset retirement obligations at January 1	2,271	2,125	2,012
Accretion	138	129	120
Liabilities incurred	1	27	1
Liabilities settled	(14)	(8)	(2)
Revision in estimated cash flows	51	(2)	(6)
Asset retirement obligations at December 31	$ 2,447	$ 2,271	$ 2,125

Asset Retirement Obligations (D

Asset Retirement Obligations (Details) - Fermi 2	Dec. 31, 2019USD ($)
Asset Retirement Obligations [Line Items]
Nuclear decommissioning liabilities funded through surcharge and included in ARO balance	$ 2,100,000,000
Liabilities balance upon completion of decommissioning	$ 0

Regulatory Matters (Schedule of

Regulatory Matters (Schedule of Regulatory Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Regulatory Assets [Line Items]
Regulatory assets	$ 4,176	$ 4,721
Less amount included in Current Assets	(5)	(153)
Regulatory assets, noncurrent	4,171	4,568
Pension
Regulatory Assets [Line Items]
Regulatory assets	1,983	1,961
Other postretirement costs
Regulatory Assets [Line Items]
Regulatory assets	201	213
Fermi 2 asset retirement obligation
Regulatory Assets [Line Items]
Regulatory assets	669	778
Recoverable undepreciated costs on retiring plants
Regulatory Assets [Line Items]
Regulatory assets	657	630
Recoverable Michigan income taxes
Regulatory Assets [Line Items]
Regulatory assets	189	201
Deferred environmental costs
Regulatory Assets [Line Items]
Regulatory assets	66	69
Recoverable income taxes related to AFUDC equity
Regulatory Assets [Line Items]
Regulatory assets	56	51
Unamortized loss on reacquired debt
Regulatory Assets [Line Items]
Regulatory assets	56	60
Customer360 deferred costs
Regulatory Assets [Line Items]
Regulatory assets	55	42
Energy Waste Reduction incentive
Regulatory Assets [Line Items]
Regulatory assets	54	49
Nuclear Performance Evaluation and Review Committee Tracker
Regulatory Assets [Line Items]
Regulatory assets	48	43
Enhanced Tree Trimming Program deferred costs
Regulatory Assets [Line Items]
Regulatory assets	43	0
Other recoverable income taxes
Regulatory Assets [Line Items]
Regulatory assets	20	23
Non-service pension and other postretirement costs
Regulatory Assets [Line Items]
Regulatory assets	15	10
Transitional Reconciliation Mechanism
Regulatory Assets [Line Items]
Regulatory assets	10	21
Accrued PSCR/GCR revenue
Regulatory Assets [Line Items]
Regulatory assets	3	116
Removal costs asset
Regulatory Assets [Line Items]
Regulatory assets	0	407
Other
Regulatory Assets [Line Items]
Regulatory assets	51	47
DTE Electric
Regulatory Assets [Line Items]
Regulatory assets	3,453	3,977
Less amount included in Current Assets	(5)	(148)
Regulatory assets, noncurrent	3,448	3,829
DTE Electric | Pension
Regulatory Assets [Line Items]
Regulatory assets	1,497	1,476
DTE Electric | Other postretirement costs
Regulatory Assets [Line Items]
Regulatory assets	131	121
DTE Electric | Fermi 2 asset retirement obligation
Regulatory Assets [Line Items]
Regulatory assets	669	778
DTE Electric | Recoverable undepreciated costs on retiring plants
Regulatory Assets [Line Items]
Regulatory assets	657	630
DTE Electric | Recoverable Michigan income taxes
Regulatory Assets [Line Items]
Regulatory assets	152	161
DTE Electric | Deferred environmental costs
Regulatory Assets [Line Items]
Regulatory assets	0	0
DTE Electric | Recoverable income taxes related to AFUDC equity
Regulatory Assets [Line Items]
Regulatory assets	47	41
DTE Electric | Unamortized loss on reacquired debt
Regulatory Assets [Line Items]
Regulatory assets	40	43
DTE Electric | Customer360 deferred costs
Regulatory Assets [Line Items]
Regulatory assets	55	42
DTE Electric | Energy Waste Reduction incentive
Regulatory Assets [Line Items]
Regulatory assets	43	39
DTE Electric | Nuclear Performance Evaluation and Review Committee Tracker
Regulatory Assets [Line Items]
Regulatory assets	48	43
DTE Electric | Enhanced Tree Trimming Program deferred costs
Regulatory Assets [Line Items]
Regulatory assets	43	0
DTE Electric | Other recoverable income taxes
Regulatory Assets [Line Items]
Regulatory assets	20	23
DTE Electric | Non-service pension and other postretirement costs
Regulatory Assets [Line Items]
Regulatory assets	0	0
DTE Electric | Transitional Reconciliation Mechanism
Regulatory Assets [Line Items]
Regulatory assets	10	21
DTE Electric | Accrued PSCR/GCR revenue
Regulatory Assets [Line Items]
Regulatory assets	3	116
DTE Electric | Removal costs asset
Regulatory Assets [Line Items]
Regulatory assets	0	407
DTE Electric | Other
Regulatory Assets [Line Items]
Regulatory assets	$ 38	$ 36

Regulatory Matters (Schedule _2

Regulatory Matters (Schedule of Regulatory Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Regulatory Liabilities [Line Items]
Regulatory liabilities	$ 3,329	$ 3,048
Less amount included in Current Liabilities	(65)	(126)
Regulatory liabilities, noncurrent	3,264	2,922
Refundable federal income taxes
Regulatory Liabilities [Line Items]
Regulatory liabilities	2,359	2,410
Removal costs liability
Regulatory Liabilities [Line Items]
Regulatory liabilities	700	253
Negative other postretirement offset
Regulatory Liabilities [Line Items]
Regulatory liabilities	93	101
Renewable energy
Regulatory Liabilities [Line Items]
Regulatory liabilities	54	86
Non-service pension and other postretirement costs
Regulatory Liabilities [Line Items]
Regulatory liabilities	46	22
Accrued PSCR/GCR refund
Regulatory Liabilities [Line Items]
Regulatory liabilities	23	0
TCJA rate reduction liability
Regulatory Liabilities [Line Items]
Regulatory liabilities	1	118
Other
Regulatory Liabilities [Line Items]
Regulatory liabilities	53	58
DTE Electric
Regulatory Liabilities [Line Items]
Regulatory liabilities	2,586	2,269
Less amount included in Current Liabilities	(40)	(98)
Regulatory liabilities, noncurrent	2,546	2,171
DTE Electric | Refundable federal income taxes
Regulatory Liabilities [Line Items]
Regulatory liabilities	1,911	1,958
DTE Electric | Removal costs liability
Regulatory Liabilities [Line Items]
Regulatory liabilities	483	0
DTE Electric | Negative other postretirement offset
Regulatory Liabilities [Line Items]
Regulatory liabilities	69	79
DTE Electric | Renewable energy
Regulatory Liabilities [Line Items]
Regulatory liabilities	54	86
DTE Electric | Non-service pension and other postretirement costs
Regulatory Liabilities [Line Items]
Regulatory liabilities	21	11
DTE Electric | Accrued PSCR/GCR refund
Regulatory Liabilities [Line Items]
Regulatory liabilities	0	0
DTE Electric | TCJA rate reduction liability
Regulatory Liabilities [Line Items]
Regulatory liabilities	0	93
DTE Electric | Other
Regulatory Liabilities [Line Items]
Regulatory liabilities	$ 48	$ 42

Regulatory Matters (Details)

Regulatory Matters (Details) - USD ($) $ in Millions	Nov. 25, 2019	Aug. 20, 2019	Jul. 08, 2019	May 02, 2019	Feb. 01, 2019	Dec. 06, 2018	Dec. 05, 2018	Nov. 16, 2018	Jul. 06, 2018	Dec. 31, 2019
Regulatory Assets [Line Items]
Deferral of investigation and remediation of costs associated with gas utilities former MGP sites										10 years
Deferral of costs associated with tree trimming surge, period of deferral										3 years
DTE Electric | MPSC | 2018 Electric Rate Case Filing
Regulatory Assets [Line Items]
Requested rate increase					$ 248.6				$ 328
Return on equity, percent				10.00%					10.00%
Return on equity, requested percent									10.50%
Approved rate increase				$ 125
DTE Electric | MPSC | 2019 Electric Rate Case Filing
Regulatory Assets [Line Items]
Requested rate increase			$ 351
Return on equity, percent			10.00%
Return on equity, requested percent			10.50%
DTE Electric | MPSC | 2016 DTE Electric Depreciation Case Filing
Regulatory Assets [Line Items]
Approved depreciation rate increase						3.72%	3.06%
DTE Gas
Regulatory Assets [Line Items]
Calculation C, reduction of annual revenue requirement, requested								$ 12
Calculation C, reduction of annual revenue requirement, approved		$ 13
DTE Gas | MPSC | 2019 Gas Rate Case Filing
Regulatory Assets [Line Items]
Requested rate increase	$ 204
Return on equity, percent	10.00%
Return on equity, requested percent	10.50%
Customer360 deferred costs
Regulatory Assets [Line Items]
Approved amortization period										15 years
Nuclear Performance Evaluation and Review Committee Tracker
Regulatory Assets [Line Items]
Approved amortization period										5 years

Income Taxes (Details)

Income Taxes (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Entity Information [Line Items]
Deferred tax asset, general business tax credit carryforwards	$ 1,010,000,000
Deferred tax asset, alternative minimum tax credit carryforwards	$ 153,000,000
Tax credit carry forwards refundable period	3 years
State and local net operating loss carry-forwards	$ 117,000,000	$ 59,000,000
Valuation allowance	40,000,000	33,000,000
Adjustment to deferred tax liabilities related to Tax Cuts and Jobs Act of 2017	2,560,000,000
True-up adjustments to remeasurement of deferred taxes		21,000,000
Unrecognized tax benefits that would impact effective tax rate	8,000,000	8,000,000
Interest on income taxes accrued	4,000,000	4,000,000
Interest on income taxes expense	1,000,000	1,000,000	$ 0
Unregulated Operation
Entity Information [Line Items]
Adjustment to deferred tax liabilities related to Tax Cuts and Jobs Act of 2017	105,000,000
Regulated Operation
Entity Information [Line Items]
True-up adjustments to remeasurement of deferred taxes		17,000,000
Refundable federal income taxes
Entity Information [Line Items]
Adjustment to deferred tax liabilities related to Tax Cuts and Jobs Act of 2017	2,450,000,000
Federal
Entity Information [Line Items]
Net operating loss carry-forwards	1,300,000,000
DTE Electric
Entity Information [Line Items]
Income tax receivable from related party	14,000,000	8,000,000
State and local net operating loss carry-forwards	0	1,000,000
Valuation allowance	0	0
True-up adjustments to remeasurement of deferred taxes		7,000,000
Unrecognized tax benefits that would impact effective tax rate	10,000,000	10,000,000
Interest on income taxes accrued	6,000,000	$ 5,000,000
Interest on income taxes expense	1,000,000		$ 0
DTE Electric | General Business Credits
Entity Information [Line Items]
Tax credit carry-forward	$ 252,000,000

Income Taxes (Reconciliation of

Income Taxes (Reconciliation of Income Tax Expense to the Statutory Federal Income Tax Rate) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Entity Information [Line Items]
Statutory rate	21.00%	21.00%	35.00%
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Income Before Income Taxes	$ 1,324	$ 1,216	$ 1,287
Income tax expense at statutory rate - 21% in 2019 and 2018 - 35% in 2017	278	255	450
Production tax credits	(128)	(223)	(189)
Investment tax credits	(4)	(4)	(4)
TCJA regulatory liability amortization	(38)	0	0
Depreciation	2	2	(4)
Noncontrolling interests	0	2	8
AFUDC equity	(4)	(14)	(18)
Employee Stock Ownership Plan dividends	(3)	(3)	(5)
Stock based compensation	(7)	(3)	(14)
State and local income taxes, net of federal benefit	48	60	51
Enactment of the Tax Cuts and Jobs Act	0	21	(105)
Other, net	8	5	5
Income Tax Expense	$ 152	$ 98	$ 175
Effective income tax rate	11.50%	8.10%	13.60%
DTE Electric
Entity Information [Line Items]
Statutory rate	21.00%	21.00%	35.00%
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Income Before Income Taxes	$ 854	$ 857	$ 928
Income tax expense at statutory rate - 21% in 2019 and 2018 - 35% in 2017	179	180	325
Production tax credits	(45)	(35)	(36)
Investment tax credits	(4)	(3)	(4)
TCJA regulatory liability amortization	(35)	0	0
Depreciation	2	2	3
AFUDC equity	(4)	(3)	(5)
Employee Stock Ownership Plan dividends	(2)	(2)	(3)
State and local income taxes, net of federal benefit	49	49	48
Enactment of the Tax Cuts and Jobs Act	0	7	0
Other, net	(2)	(2)	(1)
Income Tax Expense	$ 138	$ 193	$ 327
Effective income tax rate	16.20%	22.50%	35.20%

Income Taxes (Components of Inc

Income Taxes (Components of Income Tax Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current income tax expense (benefit)
Federal	$ (184)	$ (17)	$ (22)
State and other income tax	7	1	1
Total current income taxes	(177)	(16)	(21)
Deferred income tax expense
Federal	275	38	118
State and other income tax	54	76	78
Total deferred income taxes	329	114	196
Total	152	98	175
DTE Electric
Current income tax expense (benefit)
Federal	25	0	(17)
State and other income tax	16	4	(1)
Total current income taxes	41	4	(18)
Deferred income tax expense
Federal	51	131	270
State and other income tax	46	58	75
Total deferred income taxes	97	189	345
Total	$ 138	$ 193	$ 327

Income Taxes (Deferred Tax Asse

Income Taxes (Deferred Tax Assets (Liabilities)) (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Components of Deferred Tax Assets and Liabilities [Abstract]
Property, plant, and equipment	$ (3,755,000,000)	$ (3,462,000,000)
Regulatory assets and liabilities	(47,000,000)	(54,000,000)
Tax credit carry-forwards	1,161,000,000	1,178,000,000
Pension and benefits	300,000,000	311,000,000
Federal net operating loss carry-forward	276,000,000	117,000,000
State and local net operating loss carry-forwards	117,000,000	59,000,000
Investments in equity method investees	(465,000,000)	(216,000,000)
Other	138,000,000	125,000,000
Deferred tax liabilities, gross	(2,275,000,000)	(1,942,000,000)
Less valuation allowance	(40,000,000)	(33,000,000)
Deferred income tax liabilities	(2,315,000,000)	(1,975,000,000)
Deferred income tax assets	2,264,000,000	2,021,000,000
Deferred income tax liabilities	(4,579,000,000)	(3,996,000,000)
DTE Electric
Components of Deferred Tax Assets and Liabilities [Abstract]
Property, plant, and equipment	(2,956,000,000)	(2,840,000,000)
Regulatory assets and liabilities		(3,000,000)
Regulatory assets and liabilities	4,000,000
Tax credit carry-forwards	252,000,000	250,000,000
Pension and benefits	258,000,000	258,000,000
Federal net operating loss carry-forward	0	2,000,000
State and local net operating loss carry-forwards	0	1,000,000
Investments in equity method investees	0	(1,000,000)
Other	87,000,000	87,000,000
Deferred tax liabilities, gross	(2,355,000,000)	(2,246,000,000)
Less valuation allowance	0	0
Deferred income tax liabilities	(2,355,000,000)	(2,246,000,000)
Deferred income tax assets	865,000,000	855,000,000
Deferred income tax liabilities	$ (3,220,000,000)	$ (3,101,000,000)

Income Taxes (Reconciliation _2

Income Taxes (Reconciliation of Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits, beginning balance	$ 10	$ 10	$ 10
Additions for tax positions of prior years	0	0	0
Unrecognized tax benefits, ending balance	10	10	10
DTE Electric
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits, beginning balance	13	13	13
Additions for tax positions of prior years	0	0	0
Unrecognized tax benefits, ending balance	$ 13	$ 13	$ 13

Common Stock and Earnings Per_3

Common Stock and Earnings Per Share (Details Textuals) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	Oct. 01, 2019	Nov. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Issuance of common stock		$ 339	$ 1,023	$ 0	$ 0
Shares issued in conjunction with acquisition of Blue Union and LEAP (in shares)		2,760
Price per share (in dollars per share)		$ 126
Gross value of shares issued in conjunction with acquisition of Blue Union and LEAP		$ 348
Stock Repurchase Contract, 2016 Series C Equity Units Subject to Mandatory Redemption
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Shares of common stock issued under stock repurchase contracts (in shares)	5,870
Issuance of common stock	$ 675

Common Stock and Earnings Per_4

Common Stock and Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Basic Earnings per Share
Net Income Attributable to DTE Energy Company	$ 267	$ 319	$ 182	$ 401	$ 191	$ 334	$ 234	$ 361	$ 1,169	$ 1,120	$ 1,134
Less: Allocation of earnings to net restricted stock awards									(2)	(2)	(2)
Net income available to common shareholders — basic									$ 1,167	$ 1,118	$ 1,132
Average number of common shares outstanding — basic (in shares)									185	181	179
Basic Earnings per Common Share (in dollars per share)	$ 1.40	$ 1.74	$ 0.99	$ 2.20	$ 1.05	$ 1.84	$ 1.29	$ 2.01	$ 6.32	$ 6.18	$ 6.32
Diluted Earnings per Share
Net Income Attributable to DTE Energy Company	$ 267	$ 319	$ 182	$ 401	$ 191	$ 334	$ 234	$ 361	$ 1,169	$ 1,120	$ 1,134
Less: Allocation of earnings to net restricted stock awards									(2)	(2)	(2)
Net income available to common shareholders — diluted									$ 1,167	$ 1,118	$ 1,132
Average number of common shares outstanding — diluted (in shares)									185	181	179
Diluted Earnings per Common Share (in dollars per share)	$ 1.40	$ 1.73	$ 0.99	$ 2.19	$ 1.05	$ 1.84	$ 1.29	$ 2	$ 6.31	$ 6.17	$ 6.32
Incremental common shares attributable to dilutive effect of equity units (in shares)									9.9	6.3	6.3

Fair Value (Assets and Liabilit

Fair Value (Assets and Liabilities Recorded at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Derivative assets
Derivative assets, gross	$ 775	$ 663
Derivative assets, netting	(601)	(530)
Derivative assets, net	174	133
Liabilities
Derivative liabilities, gross	(770)	(669)
Derivative liabilities, netting	601	513
Derivative liabilities, net	(169)	(156)
Current liabilities
Liabilities
Derivative liabilities, gross	(596)	(518)
Noncurrent liabilities
Liabilities
Derivative liabilities, gross	(174)	(151)
Natural Gas
Derivative assets
Derivative assets, gross	355	349
Derivative assets, netting	(266)	(277)
Derivative assets, net	89	72
Liabilities
Derivative liabilities, gross	(351)	(380)
Derivative liabilities, netting	266	272
Derivative liabilities, net	(85)	(108)
Electricity
Derivative assets
Derivative assets, gross	306	303
Derivative assets, netting	(225)	(252)
Derivative assets, net	81	51
Liabilities
Derivative liabilities, gross	(298)	(285)
Derivative liabilities, netting	225	240
Derivative liabilities, net	(73)	(45)
Environmental & Other
Derivative assets
Derivative assets, gross	113	7
Derivative assets, netting	(110)	(1)
Derivative assets, net	3	6
Liabilities
Derivative liabilities, gross	(121)	(1)
Derivative liabilities, netting	110	1
Derivative liabilities, net	(11)	0
Interest rate contracts
Liabilities
Derivative liabilities, gross	0	(3)
Derivative liabilities, netting	0	0
Derivative liabilities, net	0	(3)
Foreign currency exchange contracts
Derivative assets
Derivative assets, gross	1	4
Derivative assets, netting	0	0
Derivative assets, net	1	4
Recurring
Assets
Cash equivalents	15	18
Derivative assets
Derivative assets, netting	(601)	(530)
Derivative assets, net	174	133
Total assets	2,073	1,712
Liabilities
Derivative liabilities, netting	601	513
Derivative liabilities, net	(169)	(156)
Net Assets (Liabilities) at end of period	1,904	1,556
Net Assets (Liabilities) at the end of the period, netting	0	(17)
Recurring | DTE Electric
Assets
Cash equivalents	11	10
Derivative assets
Total assets	1,688	1,404
Recurring | Current assets
Derivative assets
Derivative assets, netting	(513)	(461)
Total assets	148	120
Recurring | Current assets | DTE Electric
Derivative assets
Total assets	14	16
Recurring | Noncurrent assets
Derivative assets
Derivative assets, netting	(88)	(69)
Total assets	1,925	1,592
Recurring | Noncurrent assets | DTE Electric
Derivative assets
Total assets	1,674	1,388
Recurring | Current liabilities
Liabilities
Derivative liabilities, netting	513	451
Derivative liabilities, net	(83)	(67)
Recurring | Noncurrent liabilities
Liabilities
Derivative liabilities, netting	88	62
Derivative liabilities, net	(86)	(89)
Recurring | Cash and Cash equivalents
Assets
Cash equivalents	4	3
Recurring | Restricted cash
Assets
Cash equivalents		5
Recurring | Other investments
Assets
Cash equivalents	11	10
Recurring | Other investments | DTE Electric
Assets
Cash equivalents	11	10
Recurring | Natural Gas
Derivative assets
Derivative assets, netting	(266)	(277)
Derivative assets, net	89	72
Liabilities
Derivative liabilities, netting	266	272
Derivative liabilities, net	(85)	(108)
Recurring | Electricity
Derivative assets
Derivative assets, netting	(225)	(252)
Derivative assets, net	81	51
Liabilities
Derivative liabilities, netting	225	240
Derivative liabilities, net	(73)	(45)
Recurring | Environmental & Other
Derivative assets
Derivative assets, netting	(110)	(1)
Derivative assets, net	3	6
Liabilities
Derivative liabilities, netting	110	1
Derivative liabilities, net	(11)	0
Recurring | Interest rate contracts
Liabilities
Derivative liabilities, netting	0	0
Derivative liabilities, net	0	(3)
Recurring | Foreign currency exchange contracts
Derivative assets
Derivative assets, netting	0	0
Derivative assets, net	1	4
Recurring | Derivative assets — FTRs | DTE Electric
Derivative assets
Derivative assets, net	3	6
Recurring | Cash equivalents
Assets
Nuclear decommissioning trusts	34	5
Other investments	4	4
Recurring | Cash equivalents | DTE Electric
Assets
Nuclear decommissioning trusts	34	5
Recurring | Private equity and other
Assets
Nuclear decommissioning trusts	43	20
Recurring | Private equity and other | DTE Electric
Assets
Nuclear decommissioning trusts	43	20
Recurring | Equity securities
Assets
Nuclear decommissioning trusts	1,046	851
Other investments	140	110
Recurring | Equity securities | DTE Electric
Assets
Nuclear decommissioning trusts	1,046	851
Other investments	13	10
Recurring | Fixed income securities
Assets
Nuclear decommissioning trusts	538	502
Other investments	79	69
Recurring | Fixed income securities | DTE Electric
Assets
Nuclear decommissioning trusts	538	502
Recurring | Level 1
Assets
Cash equivalents	15	16
Derivative assets
Derivative assets, gross	205	199
Total assets	1,683	1,266
Liabilities
Derivative liabilities, gross	(221)	(197)
Net Assets (Liabilities) at end of period	1,462	1,069
Recurring | Level 1 | DTE Electric
Assets
Cash equivalents	11	8
Derivative assets
Total assets	1,264	886
Recurring | Level 1 | Current assets
Derivative assets
Total assets	218	212
Recurring | Level 1 | Current assets | DTE Electric
Derivative assets
Total assets	11	8
Recurring | Level 1 | Noncurrent assets
Derivative assets
Total assets	1,465	1,054
Recurring | Level 1 | Noncurrent assets | DTE Electric
Derivative assets
Total assets	1,253	878
Recurring | Level 1 | Current liabilities
Liabilities
Derivative liabilities, gross	(211)	(191)
Recurring | Level 1 | Noncurrent liabilities
Liabilities
Derivative liabilities, gross	(10)	(6)
Recurring | Level 1 | Natural Gas
Derivative assets
Derivative assets, gross	205	199
Liabilities
Derivative liabilities, gross	(221)	(197)
Recurring | Level 1 | Electricity
Derivative assets
Derivative assets, gross	0	0
Liabilities
Derivative liabilities, gross	0	0
Recurring | Level 1 | Environmental & Other
Derivative assets
Derivative assets, gross	0	0
Liabilities
Derivative liabilities, gross	0	0
Recurring | Level 1 | Interest rate contracts
Liabilities
Derivative liabilities, gross	0	0
Recurring | Level 1 | Foreign currency exchange contracts
Derivative assets
Derivative assets, gross	0	0
Recurring | Level 1 | Derivative assets — FTRs | DTE Electric
Derivative assets
Derivative assets, net	0	0
Recurring | Level 1 | Cash equivalents
Assets
Nuclear decommissioning trusts	34	5
Other investments	4	4
Recurring | Level 1 | Cash equivalents | DTE Electric
Assets
Nuclear decommissioning trusts	34	5
Recurring | Level 1 | Private equity and other
Assets
Nuclear decommissioning trusts	0	0
Recurring | Level 1 | Private equity and other | DTE Electric
Assets
Nuclear decommissioning trusts	0	0
Recurring | Level 1 | Equity securities
Assets
Nuclear decommissioning trusts	1,046	851
Other investments	140	110
Recurring | Level 1 | Equity securities | DTE Electric
Assets
Nuclear decommissioning trusts	1,046	851
Other investments	13	10
Recurring | Level 1 | Fixed income securities
Assets
Nuclear decommissioning trusts	160	12
Other investments	79	69
Recurring | Level 1 | Fixed income securities | DTE Electric
Assets
Nuclear decommissioning trusts	160	12
Recurring | Level 2
Assets
Cash equivalents	0	2
Derivative assets
Derivative assets, gross	410	338
Total assets	788	830
Liabilities
Derivative liabilities, gross	(393)	(302)
Net Assets (Liabilities) at end of period	395	528
Recurring | Level 2 | DTE Electric
Assets
Cash equivalents	0	2
Derivative assets
Total assets	378	492
Recurring | Level 2 | Current assets
Derivative assets
Total assets	320	273
Recurring | Level 2 | Current assets | DTE Electric
Derivative assets
Total assets	0	2
Recurring | Level 2 | Noncurrent assets
Derivative assets
Total assets	468	557
Recurring | Level 2 | Noncurrent assets | DTE Electric
Derivative assets
Total assets	378	490
Recurring | Level 2 | Current liabilities
Liabilities
Derivative liabilities, gross	(300)	(251)
Recurring | Level 2 | Noncurrent liabilities
Liabilities
Derivative liabilities, gross	(93)	(51)
Recurring | Level 2 | Natural Gas
Derivative assets
Derivative assets, gross	76	87
Liabilities
Derivative liabilities, gross	(41)	(71)
Recurring | Level 2 | Electricity
Derivative assets
Derivative assets, gross	223	247
Liabilities
Derivative liabilities, gross	(231)	(227)
Recurring | Level 2 | Environmental & Other
Derivative assets
Derivative assets, gross	110	0
Liabilities
Derivative liabilities, gross	(121)	(1)
Recurring | Level 2 | Interest rate contracts
Liabilities
Derivative liabilities, gross	0	(3)
Recurring | Level 2 | Foreign currency exchange contracts
Derivative assets
Derivative assets, gross	1	4
Recurring | Level 2 | Derivative assets — FTRs | DTE Electric
Derivative assets
Derivative assets, net	0	0
Recurring | Level 2 | Cash equivalents
Assets
Nuclear decommissioning trusts	0	0
Other investments	0	0
Recurring | Level 2 | Cash equivalents | DTE Electric
Assets
Nuclear decommissioning trusts	0	0
Recurring | Level 2 | Private equity and other
Assets
Nuclear decommissioning trusts	0	0
Recurring | Level 2 | Private equity and other | DTE Electric
Assets
Nuclear decommissioning trusts	0	0
Recurring | Level 2 | Equity securities
Assets
Nuclear decommissioning trusts	0	0
Other investments	0	0
Recurring | Level 2 | Equity securities | DTE Electric
Assets
Nuclear decommissioning trusts	0	0
Other investments	0	0
Recurring | Level 2 | Fixed income securities
Assets
Nuclear decommissioning trusts	378	490
Other investments	0	0
Recurring | Level 2 | Fixed income securities | DTE Electric
Assets
Nuclear decommissioning trusts	378	490
Recurring | Level 3
Assets
Cash equivalents	0	0
Derivative assets
Derivative assets, gross	160	126
Total assets	160	126
Liabilities
Derivative liabilities, gross	(156)	(170)
Net Assets (Liabilities) at end of period	4	(44)
Recurring | Level 3 | DTE Electric
Assets
Cash equivalents	0	0
Derivative assets
Total assets	3	6
Recurring | Level 3 | Current assets
Derivative assets
Total assets	123	96
Recurring | Level 3 | Current assets | DTE Electric
Derivative assets
Total assets	3	6
Recurring | Level 3 | Noncurrent assets
Derivative assets
Total assets	37	30
Recurring | Level 3 | Noncurrent assets | DTE Electric
Derivative assets
Total assets	0	0
Recurring | Level 3 | Current liabilities
Liabilities
Derivative liabilities, gross	(85)	(76)
Recurring | Level 3 | Noncurrent liabilities
Liabilities
Derivative liabilities, gross	(71)	(94)
Recurring | Level 3 | Natural Gas
Derivative assets
Derivative assets, gross	74	63
Liabilities
Derivative liabilities, gross	(89)	(112)
Recurring | Level 3 | Electricity
Derivative assets
Derivative assets, gross	83	56
Liabilities
Derivative liabilities, gross	(67)	(58)
Recurring | Level 3 | Environmental & Other
Derivative assets
Derivative assets, gross	3	7
Liabilities
Derivative liabilities, gross	0	0
Recurring | Level 3 | Interest rate contracts
Liabilities
Derivative liabilities, gross	0	0
Recurring | Level 3 | Foreign currency exchange contracts
Derivative assets
Derivative assets, gross	0	0
Recurring | Level 3 | Derivative assets — FTRs | DTE Electric
Derivative assets
Derivative assets, net	3	6
Recurring | Level 3 | Cash equivalents
Assets
Nuclear decommissioning trusts	0	0
Other investments	0	0
Recurring | Level 3 | Cash equivalents | DTE Electric
Assets
Nuclear decommissioning trusts	0	0
Recurring | Level 3 | Private equity and other
Assets
Nuclear decommissioning trusts	0	0
Recurring | Level 3 | Private equity and other | DTE Electric
Assets
Nuclear decommissioning trusts	0	0
Recurring | Level 3 | Equity securities
Assets
Nuclear decommissioning trusts	0	0
Other investments	0	0
Recurring | Level 3 | Equity securities | DTE Electric
Assets
Nuclear decommissioning trusts	0	0
Other investments	0	0
Recurring | Level 3 | Fixed income securities
Assets
Nuclear decommissioning trusts	0	0
Other investments	0	0
Recurring | Level 3 | Fixed income securities | DTE Electric
Assets
Nuclear decommissioning trusts	0	0
Recurring | Other
Derivative assets
Total assets	43	20
Liabilities
Net Assets (Liabilities) at end of period	43	20
Recurring | Other | DTE Electric
Derivative assets
Total assets	43	20
Recurring | Other | Noncurrent assets
Derivative assets
Total assets	43	20
Recurring | Other | Noncurrent assets | DTE Electric
Derivative assets
Total assets	43	20
Recurring | Other | Private equity and other
Assets
Nuclear decommissioning trusts	43	20
Recurring | Other | Private equity and other | DTE Electric
Assets
Nuclear decommissioning trusts	$ 43	$ 20

Fair Value (Reconciliation of L

Fair Value (Reconciliation of Level 3 Assets and Liabilities at Fair Value on a Recurring Basis) (Details) - Recurring - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of January 1	$ (44)	$ (9)
Transfers from Level 3 into Level 2	0	(3)
Total gains (losses)
Included in earnings	91	(116)
Recorded in Regulatory liabilities	2	9
Purchases, issuances, and settlements:
Settlements	(45)	75
Net Assets (Liabilities) as of December 31	4	(44)
The amount of total gains (losses) included in Net Income attributed to the change in unrealized gains (losses) related to assets and liabilities held at December 31, 2019 and 2018 and reflected in Operating Revenues — Non-utility operations and Fuel, purchased power, and gas — non-utility in DTE Energy's Consolidated Statements of Operations	20	(120)
Natural Gas
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of January 1	(49)	(29)
Transfers from Level 3 into Level 2	0	(3)
Total gains (losses)
Included in earnings	15	(146)
Recorded in Regulatory liabilities	0	0
Purchases, issuances, and settlements:
Settlements	19	129
Net Assets (Liabilities) as of December 31	(15)	(49)
The amount of total gains (losses) included in Net Income attributed to the change in unrealized gains (losses) related to assets and liabilities held at December 31, 2019 and 2018 and reflected in Operating Revenues — Non-utility operations and Fuel, purchased power, and gas — non-utility in DTE Energy's Consolidated Statements of Operations	(1)	(119)
Electricity
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of January 1	(2)	12
Transfers from Level 3 into Level 2	0	0
Total gains (losses)
Included in earnings	77	29
Recorded in Regulatory liabilities	0	0
Purchases, issuances, and settlements:
Settlements	(59)	(43)
Net Assets (Liabilities) as of December 31	16	(2)
The amount of total gains (losses) included in Net Income attributed to the change in unrealized gains (losses) related to assets and liabilities held at December 31, 2019 and 2018 and reflected in Operating Revenues — Non-utility operations and Fuel, purchased power, and gas — non-utility in DTE Energy's Consolidated Statements of Operations	59	15
Other
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of January 1	7	8
Transfers from Level 3 into Level 2	0	0
Total gains (losses)
Included in earnings	(1)	1
Recorded in Regulatory liabilities	2	9
Purchases, issuances, and settlements:
Settlements	(5)	(11)
Net Assets (Liabilities) as of December 31	3	7
The amount of total gains (losses) included in Net Income attributed to the change in unrealized gains (losses) related to assets and liabilities held at December 31, 2019 and 2018 and reflected in Operating Revenues — Non-utility operations and Fuel, purchased power, and gas — non-utility in DTE Energy's Consolidated Statements of Operations	(38)	(16)
DTE Electric
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of January 1	6	9
Total gains (losses)
Recorded in Regulatory liabilities	2	9
Purchases, issuances, and settlements:
Settlements	(5)	(12)
Net Assets (Liabilities) as of December 31	3	6
The amount of total gains (losses) included in Regulatory liabilities attributed to the change in unrealized gains (losses) related to assets and liabilities held at December 31, 2019 and 2018 and reflected in DTE Electric's Consolidated Statements of Financial Position	$ 3	$ 6

Fair Value (Unobservable Inputs

Fair Value (Unobservable Inputs related to Level 3 Assets and Liabilities) (Details) $ in Millions	Dec. 31, 2019USD ($)$ / MMBTU$ / MWh	Dec. 31, 2018USD ($)$ / MMBTU$ / MWh
Unobservable Input Valuation Techniques [Line Items]
Derivative Assets	$ 775	$ 663
Derivative Liabilities	(770)	(669)
Natural Gas
Unobservable Input Valuation Techniques [Line Items]
Derivative Assets	355	349
Derivative Liabilities	(351)	(380)
Electricity
Unobservable Input Valuation Techniques [Line Items]
Derivative Assets	306	303
Derivative Liabilities	$ (298)	$ (285)
Level 3 | Discounted Cash Flow | Forward basis price | Natural Gas | Minimum
Unobservable Input Valuation Techniques [Line Items]
Forward basis price | $ / MMBTU	(1.78)	(2.15)
Level 3 | Discounted Cash Flow | Forward basis price | Natural Gas | Maximum
Unobservable Input Valuation Techniques [Line Items]
Forward basis price | $ / MMBTU	5.78	5.59
Level 3 | Discounted Cash Flow | Forward basis price | Natural Gas | Weighted Average
Unobservable Input Valuation Techniques [Line Items]
Forward basis price | $ / MMBTU	(0.09)	(0.10)
Level 3 | Discounted Cash Flow | Forward basis price | Electricity | Minimum
Unobservable Input Valuation Techniques [Line Items]
Forward basis price | $ / MWh	(10)	(7)
Level 3 | Discounted Cash Flow | Forward basis price | Electricity | Maximum
Unobservable Input Valuation Techniques [Line Items]
Forward basis price | $ / MWh	6	9
Level 3 | Discounted Cash Flow | Forward basis price | Electricity | Weighted Average
Unobservable Input Valuation Techniques [Line Items]
Forward basis price | $ / MWh	0	1
Recurring | Level 3
Unobservable Input Valuation Techniques [Line Items]
Derivative Assets	$ 160	$ 126
Derivative Liabilities	(156)	(170)
Recurring | Level 3 | Natural Gas
Unobservable Input Valuation Techniques [Line Items]
Derivative Assets	74	63
Derivative Liabilities	(89)	(112)
Recurring | Level 3 | Electricity
Unobservable Input Valuation Techniques [Line Items]
Derivative Assets	83	56
Derivative Liabilities	$ (67)	$ (58)

Fair Value (Fair Value of Finan

Fair Value (Fair Value of Financial Instruments) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable — Other, excluding lessor finance leases	$ 184	$ 40
Dividends payable	195	172
Short-term borrowings	828	609
Notes payable — Other, excluding lessee finance leases	25	41
Long-term debt	16,606	13,622
Carrying Amount | DTE Electric
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable — Other, excluding lessor finance leases	9	6
Short-term borrowings	354	149
Notes payable — Other, excluding lessee finance leases	21	21
Long-term debt	7,180	6,538
Carrying Amount | DTE Electric | Affiliated entity
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term borrowings	97	101
Fair Value | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable — Other, excluding lessor finance leases	0	0
Dividends payable	195	172
Short-term borrowings	0	0
Notes payable — Other, excluding lessee finance leases	0	0
Long-term debt	2,572	1,796
Fair Value | Level 1 | DTE Electric
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable — Other, excluding lessor finance leases	0	0
Short-term borrowings	0	0
Notes payable — Other, excluding lessee finance leases	0	0
Long-term debt	0	0
Fair Value | Level 1 | DTE Electric | Affiliated entity
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term borrowings	0	0
Fair Value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable — Other, excluding lessor finance leases	0	0
Dividends payable	0	0
Short-term borrowings	828	609
Notes payable — Other, excluding lessee finance leases	0	0
Long-term debt	14,207	10,712
Fair Value | Level 2 | DTE Electric
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable — Other, excluding lessor finance leases	0	0
Short-term borrowings	354	149
Notes payable — Other, excluding lessee finance leases	0	0
Long-term debt	7,916	6,552
Fair Value | Level 2 | DTE Electric | Affiliated entity
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term borrowings	0	0
Fair Value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable — Other, excluding lessor finance leases	184	40
Dividends payable	0	0
Short-term borrowings	0	0
Notes payable — Other, excluding lessee finance leases	25	41
Long-term debt	1,252	1,317
Fair Value | Level 3 | DTE Electric
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable — Other, excluding lessor finance leases	9	6
Short-term borrowings	0	0
Notes payable — Other, excluding lessee finance leases	21	21
Long-term debt	173	161
Fair Value | Level 3 | DTE Electric | Affiliated entity
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term borrowings	$ 97	$ 101

Fair Value (Fair Value of Nucle

Fair Value (Fair Value of Nuclear Decommissioning Trust Fund Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Nuclear decommissioning trust funds	$ 1,661	$ 1,378
DTE Electric
Debt Securities, Available-for-sale [Line Items]
Nuclear decommissioning trust funds	1,661	1,378
DTE Electric | Nuclear decommissioning trusts
Debt Securities, Available-for-sale [Line Items]
Nuclear decommissioning trust funds	1,661	1,378
DTE Electric | Nuclear decommissioning trusts | Fermi 2
Debt Securities, Available-for-sale [Line Items]
Nuclear decommissioning trust funds	1,650	1,372
DTE Electric | Nuclear decommissioning trusts | Fermi 1
Debt Securities, Available-for-sale [Line Items]
Nuclear decommissioning trust funds	3	3
DTE Electric | Nuclear decommissioning trusts | Low-level radioactive waste
Debt Securities, Available-for-sale [Line Items]
Nuclear decommissioning trust funds	$ 8	$ 3

Fair Value (Gains and Losses an

Fair Value (Gains and Losses and Proceeds from the Sale of Securities by the Nuclear Decommissioning Trust Funds) (Details) - DTE Electric - Nuclear decommissioning trusts - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Realized gains	$ 56	$ 65	$ 83
Realized losses	(31)	(42)	(29)
Proceeds from sale of securities	$ 788	$ 1,203	$ 1,240

Fair Value (Fair Value and Unre

Fair Value (Fair Value and Unrealized Gains and Losses for the Nuclear Decommissioning Trust Funds) (Details) - DTE Electric - Nuclear decommissioning trusts - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Fair Value	$ 1,661	$ 1,378
Fixed income securities, fair value	538	502
Private equity and other, fair value	43	20
Cash equivalents, fair value	34	5
Unrealized gains	420	242
Fixed income securities, unrealized gains	24	7
Unrealized losses	(40)	(87)
Fixed income securities, unrealized losses	(1)	(8)
Equity securities
Debt Securities, Available-for-sale [Line Items]
Fair Value	1,046	851
Unrealized gains	396	235
Unrealized losses	$ (39)	$ (79)

Fair Value (Fair Value of Fixed

Fair Value (Fair Value of Fixed Income Securities Held in Nuclear Decommissioning Trust Funds (Details) - Nuclear decommissioning trusts - Fixed Income Securities $ in Millions	Dec. 31, 2019USD ($)
Debt Securities, Available-for-sale [Line Items]
Due within one year	$ 15
Due after one through five years	102
Due after five through ten years	109
Due after ten years	312
Fixed income securities total	$ 538

Fair Value (Details)

Fair Value (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Gains from trading securities	$ 37		$ 26
Losses from trading securities		$ 11

Financial and Other Derivativ_3

Financial and Other Derivative Instruments (Fair Value of Derivative Instruments) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 775	$ 663
Derivative Liabilities	(770)	(669)
Current derivative asset
Derivatives, Fair Value [Line Items]
Derivative Assets	646	563
Noncurrent derivative asset
Derivatives, Fair Value [Line Items]
Derivative Assets	129	100
Current derivative liability
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(596)	(518)
Noncurrent derivative liability
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(174)	(151)
Interest rate contracts
Derivatives, Fair Value [Line Items]
Derivative Liabilities	0	(3)
Natural gas
Derivatives, Fair Value [Line Items]
Derivative Assets	355	349
Derivative Liabilities	(351)	(380)
Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	306	303
Derivative Liabilities	(298)	(285)
Environmental & Other
Derivatives, Fair Value [Line Items]
Derivative Assets	113	7
Derivative Liabilities	(121)	(1)
Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	1	4
Derivatives designated as hedging instruments | Interest rate contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	0	0
Derivative Liabilities	0	(3)
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets	775	663
Derivative Liabilities	(770)	(666)
Derivatives not designated as hedging instruments | DTE Electric
Derivatives, Fair Value [Line Items]
Derivative Assets	3	6
Derivatives not designated as hedging instruments | Natural gas
Derivatives, Fair Value [Line Items]
Derivative Assets	355	349
Derivative Liabilities	(351)	(380)
Derivatives not designated as hedging instruments | Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	306	303
Derivative Liabilities	(298)	(285)
Derivatives not designated as hedging instruments | Environmental & Other
Derivatives, Fair Value [Line Items]
Derivative Assets	113	7
Derivative Liabilities	(121)	(1)
Derivatives not designated as hedging instruments | Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	1	4
Derivative Liabilities	0	0
Derivatives not designated as hedging instruments | FTRs — Other current assets | DTE Electric
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 3	$ 6

Financial and Other Derivativ_4

Financial and Other Derivative Instruments (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Letters of credit that could be used to offset net derivative liabilities	$ 6,000,000	$ 4,000,000
Letters of credit that could be used to offset net derivative assets	4,000,000	$ 8,000,000
Additional collateral, aggregate fair value	527,000,000
Derivative net liability position aggregate fair value	678,000,000
Collateral already posted fair value	0
Derivative, net asset position, fair value	593,000,000
Remaining amount of offsets to derivative net liability positions for hard and soft trigger provisions	$ 85,000,000

Financial and Other Derivativ_5

Financial and Other Derivative Instruments (Net Cash Collateral Offsetting Arrangements) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Cash collateral netted against Derivative assets	$ 0	$ (17)
Cash collateral recorded in Accounts receivable	13	10
Cash collateral recorded in Accounts payable	(3)	(6)
Total net cash collateral posted (received)	$ 10	$ (13)

Financial and Other Derivativ_6

Financial and Other Derivative Instruments (Netting Offsets of Derivative Assets and Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Derivative assets
Gross Amounts of Recognized Assets (Liabilities)	$ 775	$ 663
Gross Amounts Offset in the Consolidated Statements of Financial Position	(601)	(530)
Derivative assets, net	174	133
Derivative liabilities
Gross Amounts of Recognized Assets (Liabilities)	(770)	(669)
Gross Amounts Offset in the Consolidated Statements of Financial Position	601	513
Derivative liabilities, net	(169)	(156)
Natural gas
Derivative assets
Gross Amounts of Recognized Assets (Liabilities)	355	349
Gross Amounts Offset in the Consolidated Statements of Financial Position	(266)	(277)
Derivative assets, net	89	72
Derivative liabilities
Gross Amounts of Recognized Assets (Liabilities)	(351)	(380)
Gross Amounts Offset in the Consolidated Statements of Financial Position	266	272
Derivative liabilities, net	(85)	(108)
Electricity
Derivative assets
Gross Amounts of Recognized Assets (Liabilities)	306	303
Gross Amounts Offset in the Consolidated Statements of Financial Position	(225)	(252)
Derivative assets, net	81	51
Derivative liabilities
Gross Amounts of Recognized Assets (Liabilities)	(298)	(285)
Gross Amounts Offset in the Consolidated Statements of Financial Position	225	240
Derivative liabilities, net	(73)	(45)
Environmental & Other
Derivative assets
Gross Amounts of Recognized Assets (Liabilities)	113	7
Gross Amounts Offset in the Consolidated Statements of Financial Position	(110)	(1)
Derivative assets, net	3	6
Derivative liabilities
Gross Amounts of Recognized Assets (Liabilities)	(121)	(1)
Gross Amounts Offset in the Consolidated Statements of Financial Position	110	1
Derivative liabilities, net	(11)	0
Interest rate contracts
Derivative liabilities
Gross Amounts of Recognized Assets (Liabilities)	0	(3)
Gross Amounts Offset in the Consolidated Statements of Financial Position	0	0
Derivative liabilities, net	0	(3)
Foreign currency exchange contracts
Derivative assets
Gross Amounts of Recognized Assets (Liabilities)	1	4
Gross Amounts Offset in the Consolidated Statements of Financial Position	0	0
Derivative assets, net	$ 1	$ 4

Financial and Other Derivativ_7

Financial and Other Derivative Instruments (Netting Offsets Reconciliation to Balance Sheet) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Derivative Assets
Derivative Assets	$ 775	$ 663
Collateral adjustment	0	(17)
Derivative asset, current	133	102
Derivative assets, noncurrent	41	31
Derivative Liabilities
Derivative Liabilities	(770)	(669)
Derivative liabilities, current	(83)	(67)
Derivative liabilities, noncurrent	(86)	(89)
Current derivative asset
Derivative Assets
Derivative Assets	646	563
Counterparty netting	(513)	(451)
Collateral adjustment	0	(10)
Derivative asset, current	133	102
Noncurrent derivative asset
Derivative Assets
Derivative Assets	129	100
Counterparty netting	(88)	(62)
Collateral adjustment	0	(7)
Derivative assets, noncurrent	41	31
Current derivative liability
Derivative Liabilities
Derivative Liabilities	(596)	(518)
Counterparty netting	513	451
Collateral adjustment	0	0
Derivative liabilities, current	(83)	(67)
Noncurrent derivative liability
Derivative Liabilities
Derivative Liabilities	(174)	(151)
Counterparty netting	88	62
Collateral adjustment	0	0
Derivative liabilities, noncurrent	$ (86)	$ (89)

Financial and Other Derivativ_8

Financial and Other Derivative Instruments (Effect of Derivatives not Designated as Hedging Instruments on the Consolidated Statement of Operations) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivatives	$ 55	$ (81)	$ 128
Natural gas | Operating Revenues — Non-utility operations
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivatives	44	(42)	(74)
Natural gas | Fuel, purchased power, and gas — non-utility
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivatives	(5)	(94)	97
Electricity | Operating Revenues — Non-utility operations
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivatives	44	49	105
Environmental & Other | Operating Revenues — Non-utility operations
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivatives	(26)	(1)	2
Foreign currency exchange contracts | Operating Revenues — Non-utility operations
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivatives	$ (2)	$ 7	$ (2)

Financial and Other Derivativ_9

Financial and Other Derivative Instruments (Cumulative Gross Volume of Derivative Contracts Outstanding) (Details)	12 Months Ended
	Dec. 31, 2019CAD ($)MWhMMBTU
Natural gas (MMBtu)
Derivative [Line Items]
Commodity | MMBTU	1,699,804,805
Electricity (MWh)
Derivative [Line Items]
Commodity | MWh	31,351,229
Foreign currency exchange (CAD)
Derivative [Line Items]
Foreign currency exchange (CAD) | $	$ 78,563,487

Long-Term Debt (Long Term Debt

Long-Term Debt (Long Term Debt Outstanding and Weighted Average Interest Rates) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term debt, total	$ 16,755
Unsecured
Debt Instrument [Line Items]
Interest rate	3.20%
Long-term debt, gross	$ 6,625	$ 4,425
Other Long-Term Debt, including Non-Recourse Debt
Debt Instrument [Line Items]
Long-term debt, gross	0	1
Secured Debt, Unsecured Debt, Mortgage Notes and Other Debt
Debt Instrument [Line Items]
Long-term debt, gross	15,575	12,566
Unamortized debt discount	(24)	(16)
Unamortized debt issuance costs	(91)	(73)
Long-term debt due within one year	(682)	(1,495)
Mortgage bonds, notes, and other	$ 14,778	10,982
Junior Subordinated Debentures
Debt Instrument [Line Items]
Interest rate	5.50%
Long-term debt, gross	$ 1,180	1,180
Unamortized debt issuance costs	(34)	(35)
Long-term debt, total	1,146	1,145
DTE Electric
Debt Instrument [Line Items]
Long-term debt due within one year	(632)	0
Mortgage bonds, notes, and other	6,548	6,538
Long-term debt, total	$ 7,240
DTE Electric | Principally Secured
Debt Instrument [Line Items]
Interest rate	4.20%
Long-term debt, gross	$ 6,930	6,280
DTE Electric | Tax-Exempt Revenue Bonds
Debt Instrument [Line Items]
Interest rate	4.30%
Long-term debt, gross	$ 310	310
DTE Electric | Secured Debt, Unsecured Debt, Mortgage Notes and Other Debt
Debt Instrument [Line Items]
Long-term debt, gross	7,240	6,590
Unamortized debt discount	(15)	(11)
Unamortized debt issuance costs	(45)	(41)
Mortgage bonds, notes, and other	$ 6,548	6,538
DTE Gas | Principally Secured
Debt Instrument [Line Items]
Interest rate	4.30%
Long-term debt, gross	$ 1,710	$ 1,550

Long-Term Debt (Debt Issuances)

Long-Term Debt (Debt Issuances) (Details) - USD ($)	Dec. 31, 2019	Nov. 30, 2019	Nov. 01, 2019
Debt Instrument [Line Items]
Amount	$ 3,830,000,000
Senior Notes | June 2019 2.60% Senior Notes Maturing 2022
Debt Instrument [Line Items]
Interest Rate	2.60%
Amount	$ 300,000,000
Senior Notes | June 2019 3.40% Senior Notes Maturing 2029
Debt Instrument [Line Items]
Interest Rate	3.40%
Amount	$ 500,000,000
Senior Notes | November 2019 2.25% Senior Notes Maturing 2022
Debt Instrument [Line Items]
Interest Rate	2.25%	2.25%
Amount	$ 500,000,000	$ 500,000,000
Senior Notes | November 2019 2.95% Senior Notes Maturing 2030
Debt Instrument [Line Items]
Interest Rate	2.95%	2.95%
Amount	$ 300,000,000	$ 300,000,000
Equity Units | November 2019 Equity Units Maturing 2025
Debt Instrument [Line Items]
Interest Rate		2.25%	2.25%
Amount	$ 1,300,000,000	$ 1,300,000,000	$ 1,300,000,000
DTE Electric | Mortgage Bonds | February 2019 3.95% Mortgage Bonds Maturing in 2049
Debt Instrument [Line Items]
Interest Rate	3.95%
Amount	$ 650,000,000
DTE Gas | Mortgage Bonds | October 2019 2.95% Mortgage Bonds Maturing 2029
Debt Instrument [Line Items]
Interest Rate	2.95%
Amount	$ 140,000,000
DTE Gas | Mortgage Bonds | October 2019 3.72% Mortgage Bonds Maturing in 2049
Debt Instrument [Line Items]
Interest Rate	3.72%
Amount	$ 140,000,000

Long-Term Debt (Debt Redemption

Long-Term Debt (Debt Redemptions) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)
Debt Instrument, Redemption [Line Items]
Amount	$ 821
Senior Notes | October 2019 1.50% Senior Notes Maturing 2019
Debt Instrument, Redemption [Line Items]
Interest Rate	1.50%
Amount	$ 400
Senior Notes | December 2019 2.40% Senior Notes Maturing 2019
Debt Instrument, Redemption [Line Items]
Interest Rate	2.40%
Amount	$ 300
Other long-term debt
Debt Instrument, Redemption [Line Items]
Amount	$ 1
DTE Gas | Senior Notes | October 2019 5.00% Senior Notes Maturing 2019
Debt Instrument, Redemption [Line Items]
Interest Rate	5.00%
Amount	$ 120

Long-Term Debt (Scheduled Debt

Long-Term Debt (Scheduled Debt Maturities) (Details) $ in Millions	Dec. 31, 2019USD ($)
Maturities of Long-term Debt [Abstract]
2020	$ 682
2021	462
2022	2,716
2023	1,177
2024	1,425
2025 and Thereafter	10,293
Long-term debt, total	16,755
DTE Electric
Maturities of Long-term Debt [Abstract]
2020	632
2021	462
2022	316
2023	202
2024	400
2025 and Thereafter	5,228
Long-term debt, total	$ 7,240

Long-Term Debt (Details)

Long-Term Debt (Details) $ / shares in Units, shares in Thousands	Feb. 01, 2020$ / shares	Nov. 01, 2019USD ($)	Oct. 01, 2019shares	Mar. 31, 2020USD ($)	Nov. 30, 2019USD ($)day$ / shares	Oct. 31, 2016USD ($)$ / shares	Dec. 31, 2019USD ($)shares	Nov. 30, 2022shares	Aug. 31, 2019USD ($)
Debt Instrument [Line Items]
Amount expected to be redeemed							$ 821,000,000
Face amount							3,830,000,000
Financial instruments subject to mandatory redemption, settlement terms, share value, amount							150,000,000
Equity units subject to mandatory redemption
Debt Instrument [Line Items]
Equity units, percentage interest in attached debt instrument					0.005%	5.00%
Forward contract indexed to issuer's equity, forward rate per share (in dollars per share) | $ / shares					$ 50	$ 50
Shares of common stock issued under stock repurchase contracts (in shares) | shares			5,870
Financial instruments subject to mandatory redemption, contract adjustment rate		4.00%
Financial instruments subject to mandatory redemption, settlement terms, share value, amount							$ 150,000,000
Financial instruments subject to mandatory redemption, settlement terms, maximum number of shares (in shares) | shares							13,000
Equity units subject to mandatory redemption | Subsequent Event
Debt Instrument [Line Items]
Forward contract indexed to issuer's equity, forward rate per share (in dollars per share) | $ / shares	$ 50
Financial instruments subject to mandatory redemption, contract adjustment rate	4.00%
Financial instruments subject to mandatory redemption, contract adjustment rate, annual amount (in dollars per share) | $ / shares	$ 2
Equity units subject to mandatory redemption | Minimum | Forecast
Debt Instrument [Line Items]
Financial instruments subject to mandatory redemption, settlement terms, number of shares (in shares) | shares								8,300
Equity units subject to mandatory redemption | Maximum | Forecast
Debt Instrument [Line Items]
Financial instruments subject to mandatory redemption, settlement terms, number of shares (in shares) | shares								10,300
Equal to or greater than $157.50, 0.3175 shares of common stock | Equity units subject to mandatory redemption
Debt Instrument [Line Items]
Number of consecutive scheduled trading days | day					20
Financial instruments subject to mandatory redemption, anti-dilution provision, conversion ratio					0.3175
Equal to or greater than $157.50, 0.3175 shares of common stock | Equity units subject to mandatory redemption | Minimum
Debt Instrument [Line Items]
Financial instruments subject to mandatory redemption, anti-dilution provision, stock price threshold (in dollars per share) | $ / shares					$ 157.50
Less than $157.50, but greater than $126.00, number of shares of common stock equal to $50 divided by the AMV | Equity units subject to mandatory redemption | Minimum
Debt Instrument [Line Items]
Financial instruments subject to mandatory redemption, anti-dilution provision, stock price threshold (in dollars per share) | $ / shares					126
Less than $157.50, but greater than $126.00, number of shares of common stock equal to $50 divided by the AMV | Equity units subject to mandatory redemption | Maximum
Debt Instrument [Line Items]
Financial instruments subject to mandatory redemption, anti-dilution provision, stock price threshold (in dollars per share) | $ / shares					$ 157.50
Less than or equal to $126.00, 0.3968 shares of common stock | Equity units subject to mandatory redemption
Debt Instrument [Line Items]
Financial instruments subject to mandatory redemption, anti-dilution provision, conversion ratio					0.3968
Less than or equal to $126.00, 0.3968 shares of common stock | Equity units subject to mandatory redemption | Maximum
Debt Instrument [Line Items]
Financial instruments subject to mandatory redemption, anti-dilution provision, stock price threshold (in dollars per share) | $ / shares					$ 126
October 2016 Series C 1.5% Equity Units Maturing 2024 | Equity Units
Debt Instrument [Line Items]
Interest rate									1.50%
Face amount						$ 675,000,000			$ 675,000,000
August 2019 Series C 2.529% RSNs Maturing 2024 | Equity Units
Debt Instrument [Line Items]
Interest rate			2.529%
November 2019 Series F 2.25% RSNs Maturing 2025 | Equity Units
Debt Instrument [Line Items]
Interest rate		2.25%			2.25%
Face amount		$ 1,300,000,000			$ 1,300,000,000		$ 1,300,000,000
November 2019 Series F 2.25% RSNs Maturing 2025 | Unsuccessful remarketing | Equity Units
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage					100.00%
November 2019 2.25% Senior Notes Maturing 2022 | Senior Notes
Debt Instrument [Line Items]
Interest rate					2.25%		2.25%
Face amount					$ 500,000,000		$ 500,000,000
November 2019 2.95% Senior Notes Maturing 2030 | Senior Notes
Debt Instrument [Line Items]
Interest rate					2.95%		2.95%
Face amount					$ 300,000,000		$ 300,000,000
DTE Electric | 2010 Series A 4.89% Senior Notes Due September 2020 | Senior Notes | Subsequent Event | Forecast
Debt Instrument [Line Items]
Amount expected to be redeemed				$ 300,000,000
Interest rate				4.89%

Long-Term Debt (Equity Units an

Long-Term Debt (Equity Units and RSNs) (Details) - USD ($) shares in Millions	Nov. 01, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Nov. 30, 2019
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Total Net Proceeds	$ 1,268,000,000	$ 1,265,000,000	$ 0	$ 0
Total Long-Term Debt		3,830,000,000
Equity units subject to mandatory redemption
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Units Issued (in shares)	26
Stock Purchase Contract Annual Rate	4.00%
Stock Purchase Contract Liability	$ 150,000,000
November 2019 Equity Units Maturing 2025 | Equity Units
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Total Long-Term Debt	$ 1,300,000,000	$ 1,300,000,000			$ 1,300,000,000
RSN Annual Interest Rate	2.25%				2.25%

Preferred and Preference Secu_3

Preferred and Preference Securities (Details)	Dec. 31, 2019$ / sharesshares
DTE Electric
Preferred and Preferenced Securities [Line Items]
Preferred stock, par value (in dollars per share) | $ / shares	$ 100
Preferred stock, shares authorized (in shares) | shares	6,747,484
Preference stock, par value (in dollars per share) | $ / shares	$ 1
Preference stock shares authorized (in shares) | shares	30,000,000
DTE Gas
Preferred and Preferenced Securities [Line Items]
Preferred stock, par value (in dollars per share) | $ / shares	$ 1
Preferred stock, shares authorized (in shares) | shares	7,000,000
Preference stock, par value (in dollars per share) | $ / shares	$ 1
Preference stock shares authorized (in shares) | shares	4,000,000
DTE Energy
Preferred and Preferenced Securities [Line Items]
Preferred stock, par value (in dollars per share) | $ / shares	$ 0
Preferred stock, shares authorized (in shares) | shares	5,000,000

Short-Term Credit Arrangement_3

Short-Term Credit Arrangements and Borrowings (Details)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Short-term Debt [Line Items]
Other outstanding letters of credit	$ 1,057,000,000
Weighted average interest rate	2.00%	2.90%
Dividend restriction	$ 3,200,000,000
Retained earnings	6,587,000,000	$ 6,112,000,000
Effective limitations	0
Letters of credit
Short-term Debt [Line Items]
Other outstanding letters of credit	$ 229,000,000
DTE Electric
Short-term Debt [Line Items]
Total funded debt to capitalization ratio	0.51
Other outstanding letters of credit	$ 354,000,000
Weighted average interest rate	1.90%	2.90%
Retained earnings	$ 2,384,000,000	$ 2,162,000,000
DTE Electric | Letters of credit
Short-term Debt [Line Items]
Other outstanding letters of credit	$ 0
DTE Gas
Short-term Debt [Line Items]
Total funded debt to capitalization ratio	0.48
Other outstanding letters of credit	$ 194,000,000
DTE Gas | Letters of credit
Short-term Debt [Line Items]
Other outstanding letters of credit	$ 0
DTE Energy
Short-term Debt [Line Items]
Total funded debt to capitalization ratio	0.58
Other outstanding letters of credit	$ 509,000,000
DTE Energy | Letters of credit
Short-term Debt [Line Items]
Other outstanding letters of credit	229,000,000
DTE Energy | Demand financing agreement
Short-term Debt [Line Items]
Maximum borrowing capacity	100,000,000
Additional margin financing	50,000,000
Amount outstanding	114,000,000	$ 93,000,000
DTE Energy | Demand financing agreement plus letter of credit
Short-term Debt [Line Items]
Maximum borrowing capacity	150,000,000
DTE Energy | Other outstanding letters of credit | Letters of credit
Short-term Debt [Line Items]
Other outstanding letters of credit	$ 9,000,000
Maximum
Short-term Debt [Line Items]
Total funded debt to capitalization ratio	0.65

Short-Term Credit Arrangement_4

Short-Term Credit Arrangements and Borrowings (Schedule of Borrowings) (Details)	Dec. 31, 2019USD ($)
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 2,560,000,000
Amounts outstanding	1,057,000,000
Net availability	1,503,000,000
DTE Electric
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	500,000,000
Amounts outstanding	354,000,000
Net availability	146,000,000
DTE Gas
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	300,000,000
Amounts outstanding	194,000,000
Net availability	106,000,000
DTE Energy
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	1,760,000,000
Amounts outstanding	509,000,000
Net availability	1,251,000,000
Letters of credit
Line Of Credit Facility [Line Items]
Amounts outstanding	229,000,000
Letters of credit | DTE Electric
Line Of Credit Facility [Line Items]
Amounts outstanding	0
Letters of credit | DTE Gas
Line Of Credit Facility [Line Items]
Amounts outstanding	0
Letters of credit | DTE Energy
Line Of Credit Facility [Line Items]
Amounts outstanding	229,000,000
Letters of credit | Unsecured letter of credit facility, expiring in February 2021
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	150,000,000
Letters of credit | Unsecured letter of credit facility, expiring in February 2021 | DTE Electric
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	0
Letters of credit | Unsecured letter of credit facility, expiring in February 2021 | DTE Gas
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	0
Letters of credit | Unsecured letter of credit facility, expiring in February 2021 | DTE Energy
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	150,000,000
Letters of credit | Unsecured letter of credit facility, expiring in August 2021
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	110,000,000
Letters of credit | Unsecured letter of credit facility, expiring in August 2021 | DTE Electric
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	0
Letters of credit | Unsecured letter of credit facility, expiring in August 2021 | DTE Gas
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	0
Letters of credit | Unsecured letter of credit facility, expiring in August 2021 | DTE Energy
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	110,000,000
Revolving credit facility | Unsecured revolving credit facility, expiring April 2024
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	2,300,000,000
Revolving credit facility | Unsecured revolving credit facility, expiring April 2024 | DTE Electric
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	500,000,000
Revolving credit facility | Unsecured revolving credit facility, expiring April 2024 | DTE Gas
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	300,000,000
Revolving credit facility | Unsecured revolving credit facility, expiring April 2024 | DTE Energy
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	1,500,000,000
Commercial paper issuances
Line Of Credit Facility [Line Items]
Amounts outstanding	828,000,000
Commercial paper issuances | DTE Electric
Line Of Credit Facility [Line Items]
Amounts outstanding	354,000,000
Commercial paper issuances | DTE Gas
Line Of Credit Facility [Line Items]
Amounts outstanding	194,000,000
Commercial paper issuances | DTE Energy
Line Of Credit Facility [Line Items]
Amounts outstanding	$ 280,000,000

Leases (Details Textuals)

Leases (Details Textuals) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)agreement	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Lessee, Lease, Description [Line Items]
Percent ownership interest in Vector Pipeline	40.00%
Depreciation expense associated with property under operating leases	$ 26
Interest income recognized under finance leases	$ 5
Contingent rental revenues		$ 107	$ 91	$ 101
Pipeline System Lease
Lessee, Lease, Description [Line Items]
Percent ownership interest in Vector Pipeline		40.00%
Lessor capital lease renewal terms		5 years
Number of energy services agreements | agreement		2
Minimum
Lessee, Lease, Description [Line Items]
Lease terms	2 years
Term of operating lease contracts	3 years
Maximum
Lessee, Lease, Description [Line Items]
Lease terms	40 years
Term of operating lease contracts	24 years
DTE Electric | Minimum
Lessee, Lease, Description [Line Items]
Lease terms	2 years
DTE Electric | Maximum
Lessee, Lease, Description [Line Items]
Lease terms	40 years

Leases (Components of Lease Cos

Leases (Components of Lease Cost) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)
Lessee, Lease, Description [Line Items]
Operating lease cost	$ 41
Finance lease cost:
Amortization of right-of-use assets	4
Interest of lease liabilities	0
Total finance lease cost	4
Variable lease cost	10
Short-term lease cost	10
Total lease cost	65
DTE Electric
Lessee, Lease, Description [Line Items]
Operating lease cost	17
Finance lease cost:
Amortization of right-of-use assets	4
Interest of lease liabilities	0
Total finance lease cost	4
Variable lease cost	0
Short-term lease cost	3
Total lease cost	$ 24

Leases (Other Information) (Det

Leases (Other Information) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)
Cash paid for amounts included in the measurement of these liabilities:
Operating cash flows for finance leases	$ 5
Operating cash flows for operating leases	40
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	68
Finance leases	$ 8
Weighted Average Remaining Lease Term
Operating leases	9 years 8 months 12 days
Finance leases	9 years 1 month 6 days
Weighted Average Discount Rate
Operating leases	3.50%
Finance leases	3.10%
DTE Electric
Cash paid for amounts included in the measurement of these liabilities:
Operating cash flows for finance leases	$ 5
Operating cash flows for operating leases	16
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	27
Finance leases	$ 0
Weighted Average Remaining Lease Term
Operating leases	10 years 7 months 6 days
Finance leases	2 years
Weighted Average Discount Rate
Operating leases	3.30%
Finance leases	3.10%

Leases (Future Minimum Lease Pa

Leases (Future Minimum Lease Payments - Topic 842) (Details) $ in Millions	Dec. 31, 2019USD ($)
Operating Leases
2020	$ 38
2021	30
2022	26
2023	20
2024	12
2025 and thereafter	67
Total future minimum lease payments	193
Imputed interest	(33)
Total	160
Finance Leases
2020	5
2021	5
2022	1
2023	1
2024	1
2025 and thereafter	4
Total future minimum lease payments	17
Imputed interest	(2)
Total	15
DTE Electric
Operating Leases
2020	14
2021	13
2022	12
2023	10
2024	8
2025 and thereafter	38
Total future minimum lease payments	95
Imputed interest	(16)
Total	79
Finance Leases
2020	3
2021	4
2022	0
2023	0
2024	0
2025 and thereafter	0
Total future minimum lease payments	7
Imputed interest	0
Total	$ 7

Leases (Finance Leases Reported

Leases (Finance Leases Reported on Consolidated Statements of Financial Position) (Details) $ in Millions	Dec. 31, 2019USD ($)
Lessee, Lease, Description [Line Items]
Right-of-use assets, within Property, plant, and equipment, net	$ 15
Current lease liabilities, within Current Liabilities — Other	4
DTE Electric
Lessee, Lease, Description [Line Items]
Right-of-use assets, within Property, plant, and equipment, net	7
Current lease liabilities, within Current Liabilities — Other	$ 3

Leases (Future Minimum Lease _2

Leases (Future Minimum Lease Payments for Operating Leases - Topic 840) (Details) $ in Millions	Dec. 31, 2018USD ($)
Lessee, Lease, Description [Line Items]
2019	$ 42
2020	30
2021	18
2022	11
2023	8
2024 and thereafter	45
Total future minimum lease payments	154
DTE Electric
Lessee, Lease, Description [Line Items]
2019	17
2020	12
2021	10
2022	7
2023	5
2024 and thereafter	29
Total future minimum lease payments	$ 80

Leases (Property Under Capital

Leases (Property Under Capital Leases) (Details) $ in Millions	Dec. 31, 2018USD ($)
Capital Leased Assets [Line Items]
Gross property under capital leases	$ 18
Accumulated amortization of property under capital leases	7
DTE Electric
Capital Leased Assets [Line Items]
Gross property under capital leases	18
Accumulated amortization of property under capital leases	$ 7

Leases (Lease Income Associated

Leases (Lease Income Associated with Operating Leases) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)
Lessor, Lease, Description [Line Items]
Fixed payments	$ 65
Variable payments	128
Total lease income under operating leases	193
Operating Revenues
Lessor, Lease, Description [Line Items]
Total lease income under operating leases	130
Other Income
Lessor, Lease, Description [Line Items]
Total lease income under operating leases	$ 63

Leases (Minimum Future Rental R

Leases (Minimum Future Rental Revenues under Operating Leases) (Details) $ in Millions	Dec. 31, 2019USD ($)
Leases [Abstract]
2020	$ 64
2021	62
2022	22
2023	22
2024	22
2025 and thereafter	194
Total minimum future rental revenues under operating leases	$ 386

Leases (Property under Operatin

Leases (Property under Operating Leases - Topic 842) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Lessor, Lease, Description [Line Items]
Gross property under operating leases	$ 35,072	$ 31,810
Accumulated amortization of property under operating leases	9,755	$ 10,160
Property Under Operating Leases
Lessor, Lease, Description [Line Items]
Gross property under operating leases	445
Accumulated amortization of property under operating leases	$ 173

Leases (Components of Net Inves

Leases (Components of Net Investment in Finance Leases) (Details) $ in Millions	Dec. 31, 2019USD ($)
Leases [Abstract]
2020	$ 9
2021	4
2022	4
2023	5
2024	5
2025 and thereafter	55
Total minimum future lease receipts	82
Residual value of leased pipeline	19
Less unearned income	55
Net investment in finance lease	46
Less current portion	5
Net investment in finance lease, noncurrent	$ 41

Leases (Future Rental Revenues

Leases (Future Rental Revenues under Operating Leases) (Details) $ in Millions	Dec. 31, 2018USD ($)
Leases [Abstract]
2019	$ 66
2020	66
2021	64
2022	20
2023	20
2024 and thereafter	196
Total minimum future rental revenues under non-cancelable operating leases	$ 432

Leases (Net Investment in Capit

Leases (Net Investment in Capital Leases) (Details) $ in Millions	Dec. 31, 2018USD ($)
Leases [Abstract]
2019	$ 10
2020	9
2021	0
2022	0
2023	0
2024 and thereafter	1
Total minimum future lease receipts	20
Residual value of leased pipeline	40
Less unearned income	9
Net investment in capital lease	51
Less current portion	5
Capital lease, noncurrent	$ 46

Leases (Property under Operat_2

Leases (Property under Operating Leases - Topic 840) (Details) $ in Millions	Dec. 31, 2018USD ($)
Leases [Abstract]
Gross property under operating leases	$ 447
Accumulated amortization of property under operating leases	$ 148

Commitments and Contingencies_2

Commitments and Contingencies (Details)	12 Months Ended
	Dec. 31, 2019USD ($)employeeplantfacilityNOVsite	Jul. 31, 2019CAD ($)	Dec. 31, 2018USD ($)	Jul. 31, 2009plant
Loss Contingencies [Line Items]
Utility capital expenditures, expenditures for non-utility businesses, and contributions to equity method investees estimated for next year	$ 4,500,000,000
Reserve recorded related to pre-petition receivables	91,000,000		$ 91,000,000
Long-lived assets used in producing electric output for sale	$ 25,317,000,000		21,650,000,000
Power and Industrial Projects
Loss Contingencies [Line Items]
Number of generating plants operated with ownership interests held | plant	5
Labor force concentration risk | Workforce subject to collective bargaining arrangements
Loss Contingencies [Line Items]
Approximate number of employees | employee	5,300
Vector | Revolving Term Credit Facility
Loss Contingencies [Line Items]
Revolving term credit facility amount		$ 70,000,000
Maximum potential payments under line of credit	$ 54,000,000
PG&E | Power and Industrial Projects
Loss Contingencies [Line Items]
Reserve recorded related to pre-petition receivables	0
Long-lived assets used in producing electric output for sale	101,000,000
Equity investments, including note receivable	74,000,000
Impairment loss	0
Other than temporary decline in equity investments	$ 0
Synthetic fuel guarantees
Loss Contingencies [Line Items]
Number of days after expiration of statutes of limitations	90 days
Maximum potential liability	$ 400,000,000
Reduced emissions fuel guarantees
Loss Contingencies [Line Items]
Number of days after expiration of statutes of limitations	90 days
Maximum potential liability	$ 549,000,000
NEXUS Pipeline | DTE Gas
Loss Contingencies [Line Items]
Maximum potential liability	$ 226,000,000
Guarantee termination, minimum threshold, period following end of primary term of capacity lease agreements	2 months
NEXUS Pipeline | Texas Eastern Transmission, LP
Loss Contingencies [Line Items]
Maximum potential liability	$ 360,000,000
Percentage of all payment obligations due and payable	50.00%
Guarantee termination, minimum threshold, period following end of primary term of capacity lease agreements	2 months
NEXUS Pipeline | Vector
Loss Contingencies [Line Items]
Maximum potential liability	$ 7,000,000
Percentage of all payment obligations due and payable	50.00%
Guarantee termination, minimum threshold, period following end of primary term of capacity lease agreements	15 years
Other guarantees
Loss Contingencies [Line Items]
Maximum potential liability	$ 56,000,000
Performance surety bonds
Loss Contingencies [Line Items]
Performance bonds outstanding	$ 109,000,000
Reduction of Carbon Emissions by early 2020's
Loss Contingencies [Line Items]
Goal to reduce carbon emissions, percentage	32.00%
Reduction of Carbon Emissions by 2030
Loss Contingencies [Line Items]
Goal to reduce carbon emissions, percentage	50.00%
Reduction of Carbon Emissions by 2040
Loss Contingencies [Line Items]
Goal to reduce carbon emissions, percentage	80.00%
DTE Electric
Loss Contingencies [Line Items]
Number of power plants allegedly in violation | plant				5
Number of NOVs/FOVs currently being discussed with the EPA | NOV	2
Amount spent to comply with air pollution requirements	$ 2,400,000,000
Estimated capital expenditures	$ 0
Number of former MGP sites | site	3,000,000
Accrued for remediation related to the sites	$ 8,000,000		7,000,000
Number of permitted engineered coal ash storage facilities owned | facility	3
Utility capital expenditures, expenditures for non-utility businesses, and contributions to equity method investees estimated for next year	$ 2,600,000,000
Reserve recorded related to pre-petition receivables	46,000,000		53,000,000
Long-lived assets used in producing electric output for sale	$ 17,573,000,000		15,437,000,000
DTE Electric | Labor force concentration risk | Workforce subject to collective bargaining arrangements
Loss Contingencies [Line Items]
Approximate number of employees | employee	2,800
DTE Electric | Reduction of Carbon Emissions by 2050
Loss Contingencies [Line Items]
Goal of net carbon emissions, percentage	0.00%
DTE Electric | Coal Combustion Residual Rule
Loss Contingencies [Line Items]
Estimated impact of the current rule	$ 608,000,000
DTE Gas
Loss Contingencies [Line Items]
Number of former MGP sites | site	14
Accrued for remediation related to the sites	$ 25,000,000		$ 25,000,000
Amortization period for MGP costs (in years)	10 years
DTE Gas | NEXUS Pipeline | DTE Gas
Loss Contingencies [Line Items]
Percentage of all payment obligations due and payable	50.00%
DTE Gas | Cleanup completed and site closed
Loss Contingencies [Line Items]
Number of former MGP sites | site	8
DTE Gas | Partial closure completed
Loss Contingencies [Line Items]
Number of former MGP sites | site	4
NEXUS | NEXUS Pipeline | DTE Gas
Loss Contingencies [Line Items]
Capacity lease agreement term	15 years
NEXUS | NEXUS Pipeline | Texas Eastern Transmission, LP
Loss Contingencies [Line Items]
Capacity lease agreement term	15 years
NEXUS | NEXUS Pipeline | Vector
Loss Contingencies [Line Items]
Capacity lease agreement term	15 years

Commitments and Contingencies_3

Commitments and Contingencies (Purchase Commitments) (Details) $ in Millions	Dec. 31, 2019USD ($)
Purchase Obligation, Fiscal Year Maturity [Abstract]
2020	$ 3,152
2021	1,055
2022	561
2023	418
2024	365
2025 and thereafter	1,503
Total purchase commitments	7,054
DTE Electric
Purchase Obligation, Fiscal Year Maturity [Abstract]
2020	1,556
2021	299
2022	95
2023	96
2024	96
2025 and thereafter	688
Total purchase commitments	$ 2,830

Nuclear Operations (Details)

Nuclear Operations (Details) - DTE Electric $ in Millions	May 16, 2014kWh	May 15, 2014$ / MWh	Dec. 31, 2019USD ($)
Entity Information [Line Items]
Policy waiting period			84 days
Insurance coverage for extra expense when power plant unavailable			$ 490
Period of coverage of policy for extra expenses			3 years
Primary coverage for stabilization, decontamination, debris removal, repair and/or replacement of property, and decommissioning			$ 1,500
Excess coverage for stabilization, decontamination, debris removal, repair and/or replacement of property, and decommissioning			1,250
Combined coverage limit for total property damage			2,750
Total limit for property damage for non-nuclear events			2,000
Limit of coverage for aggregate extra expenses for non-nuclear events			$ 328
Period of coverage for extra expenses			2 years
Time period for TRIA after the first loss from terrorism			1 year
NEIL policies against terrorism loss, amount made available to all insured entities (up to)			$ 3,200
Maximum assessment if loss amount exceeds funds available			42
Public liability insurance for a nuclear incident			450
One industry aggregate limit of coverage arising from terrorist act outside scope of TRIA			300
Maximum deferred premium charges that could be levied against each licensed nuclear facility			138
Limit of deferred premium charges per year per facility			$ 20
Company obligated to pay DOE fee of Fermi 2 electricity generated and sold | $ / MWh		1
New DOE fee for Fermi 2 electricity generated and sold | kWh	0

Retirement Benefits and Trust_3

Retirement Benefits and Trusteed Assets (Pension Plan - Pension Cost Inclusions) (Details) - Pension plan - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	$ 84	$ 99	$ 92
Interest cost	219	202	214
Expected return on plan assets	(325)	(329)	(311)
Amortization of:
Net actuarial loss	133	176	176
Prior service cost	1	0	1
Net pension cost/other postretirement cost (credit)	$ 112	$ 148	$ 172

Retirement Benefits and Trust_4

Retirement Benefits and Trusteed Assets (Pension Plan - Other Changes in Plan Assets and Benefit Obligations recognized in Reg Assets and OCI) (Details) - Pension plan - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Other changes in plan assets and benefit obligations recognized in Regulatory assets and Other comprehensive income (loss)
Net actuarial loss	$ 156	$ 125
Amortization of net actuarial loss	(133)	(176)
Amortization of prior service cost	(1)	0
Total recognized in Regulatory assets and Other comprehensive income (loss)	22	(51)
Total recognized in net periodic pension cost, Regulatory assets, and Other comprehensive income (loss)	134	97
Estimated amounts to be amortized from Regulatory assets and Accumulated other comprehensive income (loss) into net periodic benefit cost during next fiscal year
Net actuarial loss	171	131
Prior service cost	$ 1	$ 1

Retirement Benefits and Trust_5

Retirement Benefits and Trusteed Assets (Pension Plan - Reconciliation of Obligations, Assets and Funded Status of Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Amounts recognized in Regulatory assets
Regulatory assets	$ 4,176	$ 4,721
Pension plan
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Accumulated benefit obligation, end of year	5,387	4,779
Change in projected benefit obligation
Projected/Accumulated postretirement benefit obligation, beginning of year	5,124	5,576
Service cost	84	99	$ 92
Interest cost	219	202	214
Actuarial (gain) loss	719	(438)
Benefits paid	(336)	(315)
Projected/Accumulated postretirement benefit obligation, end of year	5,810	5,124	5,576
Change in plan assets
Plan assets at fair value, beginning of year	4,273	4,636
Actual return on plan assets	888	(233)
Company contributions	168	185
Benefits paid	(336)	(315)
Plan assets at fair value, end of year	4,993	4,273	$ 4,636
Funded status	(817)	(851)
Amount recorded as:
Current liabilities	(9)	(14)
Noncurrent liabilities	(808)	(837)
Defined benefit plans liabilities	(817)	(851)
Amounts recognized in Accumulated other comprehensive income (loss), pre-tax
Net actuarial loss	153	152
Prior service cost	4	5
Amounts recognized in Accumulated other comprehensive income (loss), pre-tax	157	157
Amounts recognized in Regulatory assets
Net actuarial loss	1,995	1,973
Prior service credit	(12)	(12)
Regulatory assets	$ 1,983	$ 1,961

Retirement Benefits and Trust_6

Retirement Benefits and Trusteed Assets (Pension Plan - Contributions) (Details) - Pension Plan - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Cash contributions to qualified pension plans	$ 168	$ 185
Qualified Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Cash contributions to qualified pension plans	150	175	$ 223
Qualified Plan | DTE Electric
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Cash contributions to qualified pension plans	$ 100	$ 175	$ 185

Retirement Benefits and Trust_7

Retirement Benefits and Trusteed Assets (Pension Plan - Contributions to DTE Energy Company Affiliates Employee Benefit Plans Master Trust) (Details) - USD ($) $ / shares in Units, $ in Millions	Mar. 05, 2019	Dec. 31, 2019	Dec. 31, 2018	Nov. 30, 2019
Defined Contribution Plan Disclosure [Line Items]
Price per Share (in dollars per share)				$ 126
Amount		$ 100	$ 175
Pension Plan
Defined Contribution Plan Disclosure [Line Items]
Number of Shares (in shares)	814,597
Price per Share (in dollars per share)	$ 122.76
Amount	$ 100

Retirement Benefits and Trust_8

Retirement Benefits and Trusteed Assets (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined contribution plan, cost recognized		$ 65	$ 61	$ 57
Annual contributions per employee, percentage		4.00%
DTE Electric
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined contribution plan, cost recognized		$ 31	29	27
DTE Gas
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Annual contributions per employee, percentage		8.00%
Pension plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Cash contributions to qualified pension plans		$ 168	185
Expected return on plan assets for next fiscal year		7.10%
Pension plan | Qualified Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Additional cash contributions to qualified pension plans		$ 50
Cash contributions to qualified pension plans		150	175	223
Pension plan | DTE Electric
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Allocated pension benefit costs		93	120	136
Pension plan | DTE Electric | Qualified Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Allocated pension benefit costs	$ 100
Cash contributions to qualified pension plans		100	175	185
Pension plan | Maximum | Qualified Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Estimated future employer contributions in next fiscal year		185
Pension plan | Maximum | DTE Electric | Qualified Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Estimated future employer contributions in next fiscal year		$ 160
Other postretirement benefit plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected return on plan assets for next fiscal year		7.20%
Retiree health care allowance will increase at lower of the rate of medical inflation or a set percentage		2.00%
Defined benefit plan, effect of one percentage point increase on service and interest cost components		$ 3
Defined benefit plan, effect of one percentage point increase on accumulated postretirement benefit obligation		62
Defined benefit plan, effect of one percentage point decrease on service and interest cost components		3
Defined benefit plan, effect of one percentage point decrease on accumulated postretirement benefit obligation		54
Other postretirement benefit plan | DTE Electric
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan, effect of one percentage point increase on service and interest cost components		2
Defined benefit plan, effect of one percentage point increase on accumulated postretirement benefit obligation		44
Defined benefit plan, effect of one percentage point decrease on service and interest cost components		2
Defined benefit plan, effect of one percentage point decrease on accumulated postretirement benefit obligation		39
Retiree healthcare plan (VEBA)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined contribution plan, cost recognized		13	11	8
Retiree healthcare plan (VEBA) | DTE Electric
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined contribution plan, cost recognized		$ 6	$ 5	$ 5

Retirement Benefits and Trust_9

Retirement Benefits and Trusteed Assets (Pension Plan - Benefits related to Qualified and Nonqualified Pension Plans Expected to be paid in the Next Ten Years) (Details) - Pension plan $ in Millions	Dec. 31, 2019USD ($)
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2020	$ 311
2021	319
2022	324
2023	330
2024	334
2025-2029	1,723
Total	$ 3,341

Retirement Benefits and Trus_10

Retirement Benefits and Trusteed Assets (Pension Plan - Assumptions used in Determining the PBO and Net Pension Costs) (Details) - Pension plan	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Projected benefit obligation
Discount rate	3.28%	4.40%	3.70%
Rate of compensation increase	4.98%	4.98%	4.98%
Net pension costs
Discount rate	4.40%	3.70%	4.25%
Rate of compensation increase	4.98%	4.98%	4.65%
Expected long-term rate of return on plan assets	7.30%	7.50%	7.50%

Retirement Benefits and Trus_11

Retirement Benefits and Trusteed Assets (Pension Plan - Target Allocations of Plan Assets) (Details) - Pension plan	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	100.00%
U.S. Large Capitalization (Cap) Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	16.00%
U.S. Small Cap and Mid Cap Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	4.00%
Non-U.S. Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	15.00%
Fixed Income Securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	42.00%
Hedge Funds and Similar Investments
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	14.00%
Private Equity and Other
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	9.00%

Retirement Benefits and Trus_12

Retirement Benefits and Trusteed Assets (Pension Plan - Fair Value Measurements) (Details) - Pension Plan - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	$ 4,993	$ 4,273	$ 4,636
Assets valued at NAV	2,145	1,181
Short-term Investments
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	99	27
Equity Securities, Domestic
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	1,042	733
Assets valued at NAV	870	0
Equity Securities, International
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	709	586
Assets valued at NAV	322	240
Fixed Income Securities, Governmental
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	569	868
Assets valued at NAV	0	0
Fixed Income Securities, Corporate
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	1,452	1,030
Assets valued at NAV	0	0
Hedge Funds and Similar Investments
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	671	630
Assets valued at NAV	502	542
Private Equity and Other
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	451	399
Assets valued at NAV	451	399
Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	1,396	1,160
Level 1 | Short-term Investments
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	99	0
Level 1 | Equity Securities, Domestic
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	172	729
Level 1 | Equity Securities, International
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	387	337
Level 1 | Fixed Income Securities, Governmental
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	569	0
Level 1 | Fixed Income Securities, Corporate
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	6
Level 1 | Hedge Funds and Similar Investments
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	169	88
Level 1 | Private Equity and Other
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	0
Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	1,452	1,932
Level 2 | Short-term Investments
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	27
Level 2 | Equity Securities, Domestic
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	4
Level 2 | Equity Securities, International
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	9
Level 2 | Fixed Income Securities, Governmental
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	868
Level 2 | Fixed Income Securities, Corporate
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	1,452	1,024
Level 2 | Hedge Funds and Similar Investments
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	0
Level 2 | Private Equity and Other
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	$ 0	$ 0

Retirement Benefits and Trus_13

Retirement Benefits and Trusteed Assets (OPEB - Postretirement Cost Inclusions) (Details) - Other postretirement benefit plan - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 22	$ 27	$ 27
Interest cost	70	69	73
Expected return on plan assets	(96)	(143)	(130)
Amortization of:
Net actuarial loss	12	11	13
Prior service credit	(9)	0	(14)
Net pension cost/other postretirement cost (credit)	(1)	(36)	(31)
DTE Electric
Defined Benefit Plan Disclosure [Line Items]
Service cost	16	20	20
Interest cost	53	53	56
Expected return on plan assets	(65)	(98)	(90)
Amortization of:
Net actuarial loss	5	8	8
Prior service credit	(7)	0	(10)
Net pension cost/other postretirement cost (credit)	$ 2	$ (17)	$ (16)

Retirement Benefits and Trus_14

Retirement Benefits and Trusteed Assets (OPEB - Other Changes in Plan Assets and APBO Recognized in Regulatory Assets and OCI) (Details) - Other postretirement benefit plan - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Other changes in plan assets and accumulated postretirement benefit obligation recognized in Regulatory assets and Other comprehensive income (loss)
Net actuarial (gain) loss	$ 34	$ (8)
Amortization of net actuarial loss	(12)	(11)
Prior service credit (cost)	(53)	(44)
Amortization of prior service (cost) credit	9	0
Total recognized in Regulatory assets and Other comprehensive income (loss)	(22)	(63)
Total recognized in net periodic pension cost, Regulatory assets, and Other comprehensive income (loss)	(23)	(99)
Estimated amounts to be amortized from Regulatory assets and Accumulated other comprehensive income (loss) into net periodic benefit cost during next fiscal year
Net actuarial loss	16	12
Prior service credit	(19)	(9)
DTE Electric
Other changes in plan assets and accumulated postretirement benefit obligation recognized in Regulatory assets and Other comprehensive income (loss)
Net actuarial (gain) loss	41	(46)
Amortization of net actuarial loss	(5)	(8)
Prior service credit (cost)	(33)	0
Amortization of prior service (cost) credit	7	(35)
Total recognized in Regulatory assets and Other comprehensive income (loss)	10	(89)
Total recognized in net periodic pension cost, Regulatory assets, and Other comprehensive income (loss)	12	(106)
Estimated amounts to be amortized from Regulatory assets and Accumulated other comprehensive income (loss) into net periodic benefit cost during next fiscal year
Net actuarial loss	11	5
Prior service credit	$ (14)	$ (7)

Retirement Benefits and Trus_15

Retirement Benefits and Trusteed Assets (OPEB - Reconciliation of Obligations, Assets and Funded Status of Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Amounts recognized in Regulatory assets
Regulatory assets	$ 4,176	$ 4,721
Other postretirement benefit plan
Change in accumulated postretirement benefit obligation
Projected/Accumulated postretirement benefit obligation, beginning of year	1,645	1,910
Service cost	22	27	$ 27
Interest cost	70	69	73
Plan amendments	(53)	(44)
Actuarial (gain) loss	153	(227)
Benefits paid	(86)	(90)
Projected/Accumulated postretirement benefit obligation, end of year	1,751	1,645	1,910
Change in plan assets
Plan assets at fair value, beginning of year	1,689	1,848
Actual return on plan assets	215	(75)
Benefits paid	(85)	(84)
Plan assets at fair value, end of year	1,819	1,689	1,848
Funded status	68	44
Amount recorded as:
Noncurrent assets	69	45
Current liabilities	(1)	(1)
Noncurrent liabilities	0	0
Defined benefit plans assets (liabilities)	68	44
Amounts recognized in Accumulated other comprehensive income (loss), pre-tax
Net actuarial (gain) loss	(8)	1
Amounts recognized in Accumulated other comprehensive income (loss), pre-tax	(8)	1
Amounts recognized in Regulatory assets
Net actuarial loss	289	257
Prior service credit	(88)	(44)
Regulatory assets	201	213
DTE Electric
Amounts recognized in Regulatory assets
Regulatory assets	3,453	3,977
DTE Electric | Other postretirement benefit plan
Change in accumulated postretirement benefit obligation
Projected/Accumulated postretirement benefit obligation, beginning of year	1,247	1,470
Service cost	16	20	20
Interest cost	53	53	56
Plan amendments	(33)	(35)
Actuarial (gain) loss	118	(196)
Benefits paid	(64)	(65)
Projected/Accumulated postretirement benefit obligation, end of year	1,337	1,247	1,470
Change in plan assets
Plan assets at fair value, beginning of year	1,158	1,272
Actual return on plan assets	141	(52)
Benefits paid	(63)	(62)
Plan assets at fair value, end of year	1,236	1,158	$ 1,272
Funded status	(101)	(89)
Amount recorded as:
Noncurrent assets	266	189
Current liabilities	0	0
Noncurrent liabilities	(367)	(278)
Defined benefit plans assets (liabilities)	(101)	(89)
Amounts recognized in Accumulated other comprehensive income (loss), pre-tax
Net actuarial (gain) loss	0	0
Amounts recognized in Accumulated other comprehensive income (loss), pre-tax	0	0
Amounts recognized in Regulatory assets
Net actuarial loss	193	156
Prior service credit	(62)	(35)
Regulatory assets	$ 131	$ 121

Retirement Benefits and Trus_16

Retirement Benefits and Trusteed Assets (OPEB - Benefits related to Qualified and Nonqualified Pension Plans Expected to be paid in the Next Ten Years) (Details) - Other postretirement benefit plan $ in Millions	Dec. 31, 2019USD ($)
Defined Benefit Plan Disclosure [Line Items]
2020	$ 84
2021	88
2022	92
2023	94
2024	96
2025-2029	496
Total	950
DTE Electric
Defined Benefit Plan Disclosure [Line Items]
2020	64
2021	67
2022	70
2023	72
2024	73
2025-2029	378
Total	$ 724

Retirement Benefits and Trus_17

Retirement Benefits and Trusteed Assets (OPEB - Assumptions used in Determining the PBO and Net Pension Costs) (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated postretirement benefit obligation
Ultimate health care trend rate			4.50%
Other postretirement benefit costs
Ultimate health care trend rate			4.50%
Other postretirement benefit plan
Accumulated postretirement benefit obligation
Discount rate	3.29%	4.40%	3.70%
Health care trend rate pre- 65	6.75%	6.75%	6.75%
Health care trend post- 65	7.25%	7.25%	7.25%
Ultimate health care trend rate	4.50%	4.50%	4.50%
Other postretirement benefit costs
Discount rate	4.40%	3.70%	4.25%
Expected long-term rate of return on plan assets	7.30%	7.75%	7.75%
Health care trend rate pre- 65	6.75%	6.75%	6.50%
Health care trend post- 65	7.25%	7.25%	6.75%
Ultimate health care trend rate	4.50%	4.50%	4.50%

Retirement Benefits and Trus_18

Retirement Benefits and Trusteed Assets (OPEB - Target Allocations of Plan Assets) (Details) - Other postretirement benefit plan	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	100.00%
U.S. Large Cap Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	16.00%
U.S. Small Cap and Mid Cap Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	3.00%
Non-U.S. Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	16.00%
Fixed Income Securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	37.00%
Hedge Funds and Similar Investments
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	14.00%
Private Equity and Other
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	14.00%

Retirement Benefits and Trus_19

Retirement Benefits and Trusteed Assets (OPEB - Fair Value Measurements) (Details) - Other postretirement benefit plan - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	$ 1,819	$ 1,689	$ 1,848
Assets valued at NAV	1,105	681
Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	458	656
Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	256	352
Short-term Investments
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	80	16
Short-term Investments | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	80	14
Short-term Investments | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	2
Equity Securities, Domestic
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	324	300
Assets valued at NAV	273	0
Equity Securities, Domestic | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	51	300
Equity Securities, Domestic | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	0
Equity Securities, International
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	271	301
Assets valued at NAV	89	67
Equity Securities, International | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	182	234
Equity Securities, International | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	0
Fixed Income Securities, Governmental
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	74	85
Assets valued at NAV	0	0
Fixed Income Securities, Governmental | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	74	0
Fixed Income Securities, Governmental | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	85
Fixed Income Securities, Corporate
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	507	406
Assets valued at NAV	251	130
Fixed Income Securities, Corporate | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	11
Fixed Income Securities, Corporate | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	256	265
Hedge Funds and Similar Investments
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	253	300
Assets valued at NAV	182	203
Hedge Funds and Similar Investments | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	71	97
Hedge Funds and Similar Investments | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	0
Private Equity and Other
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	310	281
Assets valued at NAV	310	281
Private Equity and Other | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	0
Private Equity and Other | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	0
DTE Electric
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	1,236	1,158	$ 1,272
Assets valued at NAV	758	471
DTE Electric | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	310	454
DTE Electric | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	168	233
DTE Electric | Short-term Investments
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	55	11
DTE Electric | Short-term Investments | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	55	10
DTE Electric | Short-term Investments | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	1
DTE Electric | Equity Securities, Domestic
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	219	206
Assets valued at NAV	185	0
DTE Electric | Equity Securities, Domestic | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	34	206
DTE Electric | Equity Securities, Domestic | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	0
DTE Electric | Equity Securities, International
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	184	208
Assets valued at NAV	60	45
DTE Electric | Equity Securities, International | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	124	163
DTE Electric | Equity Securities, International | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	0
DTE Electric | Fixed Income Securities, Governmental
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	48	53
Assets valued at NAV	0	0
DTE Electric | Fixed Income Securities, Governmental | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	48	0
DTE Electric | Fixed Income Securities, Governmental | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	53
DTE Electric | Fixed Income Securities, Corporate
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	344	278
Assets valued at NAV	176	92
DTE Electric | Fixed Income Securities, Corporate | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	7
DTE Electric | Fixed Income Securities, Corporate | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	168	179
DTE Electric | Hedge Funds and Similar Investments
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	172	207
Assets valued at NAV	123	139
DTE Electric | Hedge Funds and Similar Investments | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	49	68
DTE Electric | Hedge Funds and Similar Investments | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	0
DTE Electric | Private Equity and Other
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	214	195
Assets valued at NAV	214	195
DTE Electric | Private Equity and Other | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	0	0
DTE Electric | Private Equity and Other | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets at fair value	$ 0	$ 0

Stock-Based Compensation (Detai

Stock-Based Compensation (Details)	12 Months Ended
	Dec. 31, 2019USD ($)shares	Dec. 31, 2018USD ($)shares	Dec. 31, 2017USD ($)shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized limit of common stock shares (in shares)	16,500,000
Performance units price per unit (in dollars per share)	1
Options grants in period (in shares)	0	0
Stock option expense | $	$ 0	$ 0	$ 0
DTE Electric | DTE Energy
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost charged against income (in millions) | $	$ 43,000,000	38,000,000	34,000,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum award per employee (in shares)	500,000
Award expiration period	10 years
Award vesting period	3 years
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum award per employee (in shares)	150,000
Award vesting period	3 years
Compensation cost charged against income (in millions) | $	$ 11,000,000	$ 11,000,000	$ 11,000,000
Performance Share Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum award per employee (in shares)	300,000
Award vesting period	3 years
Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum award per employee (in shares)	1,000,000

Stock-Based Compensation (Compo

Stock-Based Compensation (Components of Stock Based Compensation) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Components of stock based-compensation [Abstract]
Stock-based compensation expense	$ 71	$ 64	$ 58
Tax benefit	13	13	23
Stock-based compensation cost capitalized in Property, plant, and equipment	$ 16	$ 11	$ 9

Stock-Based Compensation (Perfo

Stock-Based Compensation (Performance Share Awards Compensation Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Compensation Expense Recorded [Line Items]
Compensation expense	$ 71	$ 64	$ 58
Performance Share Awards
Compensation Expense Recorded [Line Items]
Compensation expense	60	53	47
Cash settlements	19	13	15
Stock settlements	$ 79	$ 39	$ 66

Stock-Based Compensation (Per_2

Stock-Based Compensation (Performance Share Awards Activity) (Details) - Performance shares	12 Months Ended
	Dec. 31, 2019$ / sharesshares
Performance Shares
Balance at beginning of period (in shares) | shares	1,286,686
Grants (in shares) | shares	446,579
Forfeitures (in shares) | shares	(44,044)
Payouts (in shares) | shares	(463,190)
Balance at end of period (in shares) | shares	1,226,031
Weighted Average Grant Date Fair Value
Balance at beginning of period (in dollars per share) | $ / shares	$ 97.17
Grants (in dollars per share) | $ / shares	115.85
Forfeitures (in dollars per share) | $ / shares	102.42
Payouts (in dollars per share) | $ / shares	88.53
Balance at end of period (in dollars per share) | $ / shares	$ 107.35

Stock-Based Compensation (Unrec

Stock-Based Compensation (Unrecognized Compensation Costs) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)
Share Based Compensation Unrecognized and Non-Vested Cost [Line Items]
Unrecognized Compensation Cost	$ 81
Weighted Average to be Recognized	1 year 2 months 1 day
Stock awards
Share Based Compensation Unrecognized and Non-Vested Cost [Line Items]
Unrecognized Compensation Cost	$ 19
Weighted Average to be Recognized	1 year 6 months 25 days
Performance shares
Share Based Compensation Unrecognized and Non-Vested Cost [Line Items]
Unrecognized Compensation Cost	$ 62
Weighted Average to be Recognized	1 year 18 days

Segment and Related Informati_3

Segment and Related Information (Details) customer in Millions	Dec. 31, 2019customer
Segment Reporting [Abstract]
Number of electric utility customers	2.2
Number of gas utility customers	1.3

Segment and Related Informati_4

Segment and Related Information (Financial Data - Inter-Segment Billing) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Revenues	$ (3,148)	$ (3,119)	$ (2,888)	$ (3,514)	$ (3,750)	$ (3,550)	$ (3,159)	$ (3,753)	$ (12,669)	$ (14,212)	$ (12,607)
Electric
Segment Reporting Information [Line Items]
Revenues									(5,229)	(5,298)
Gas
Segment Reporting Information [Line Items]
Revenues									(1,482)	(1,436)
Gas Storage and Pipelines
Segment Reporting Information [Line Items]
Revenues									(501)	(485)
Power and Industrial Projects
Segment Reporting Information [Line Items]
Revenues									(1,560)	(2,204)
Energy Trading
Segment Reporting Information [Line Items]
Revenues									(4,610)	(5,557)
Reclassifications and Eliminations
Segment Reporting Information [Line Items]
Revenues									715	771	704
Reclassifications and Eliminations | Electric
Segment Reporting Information [Line Items]
Revenues									56	52	48
Reclassifications and Eliminations | Gas
Segment Reporting Information [Line Items]
Revenues									12	12	8
Reclassifications and Eliminations | Gas Storage and Pipelines
Segment Reporting Information [Line Items]
Revenues									27	36	42
Reclassifications and Eliminations | Power and Industrial Projects
Segment Reporting Information [Line Items]
Revenues									596	642	569
Reclassifications and Eliminations | Energy Trading
Segment Reporting Information [Line Items]
Revenues									22	27	35
Reclassifications and Eliminations | Corporate and Other
Segment Reporting Information [Line Items]
Revenues									$ 2	$ 2	$ 2

Segment and Related Informati_5

Segment and Related Information (Financial Data - Operating Revenues Including Inter-Segment Revenues) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Operating Revenues — Utility operations									$ 6,638	$ 6,670	$ 6,434
Operating Revenues — Non-utility operations									6,031	7,542	6,173
Depreciation and amortization									1,263	1,124	1,030
Interest expense									641	559	536
Interest income									(17)	(12)	(12)
Equity in earnings of equity method investees									111	132	102
Income Tax Expense (Benefit)									152	98	175
Net Income (Loss) Attributable to DTE Energy Company	$ 267	$ 319	$ 182	$ 401	$ 191	$ 334	$ 234	$ 361	1,169	1,120	1,134
Investments in equity method investees	1,862				1,771				1,862	1,771	1,073
Capital expenditures and acquisitions									5,467	2,713	2,250
Goodwill	2,464				2,293				2,464	2,293	2,293
Total Assets	41,882				36,288				41,882	36,288	33,767
Effect of the Tax Cuts and Jobs Act of 2017									0	21	(105)
Gas Storage and Pipelines
Segment Reporting Information [Line Items]
Investments in equity method investees	1,685				1,585				1,685	1,585
Operating Segments | Electric
Segment Reporting Information [Line Items]
Operating Revenues — Utility operations									5,224	5,298	5,102
Operating Revenues — Non-utility operations									5	0	0
Depreciation and amortization									949	836	753
Interest expense									315	283	274
Interest income									(2)	0	0
Equity in earnings of equity method investees									1	0	1
Income Tax Expense (Benefit)									137	193	321
Net Income (Loss) Attributable to DTE Energy Company									714	664	606
Investments in equity method investees	5				7				5	7	7
Capital expenditures and acquisitions									2,368	1,979	1,574
Goodwill	1,208				1,208				1,208	1,208	1,208
Total Assets	24,617				22,501				24,617	22,501	21,163
Operating Segments | Electric | Non-utility Entities
Segment Reporting Information [Line Items]
Effect of the Tax Cuts and Jobs Act of 2017											(5)
Operating Segments | Gas
Segment Reporting Information [Line Items]
Operating Revenues — Utility operations									1,482	1,436	1,388
Operating Revenues — Non-utility operations									0		0
Depreciation and amortization									144	133	123
Interest expense									78	70	65
Interest income									(6)	(6)	(7)
Equity in earnings of equity method investees									2	2	2
Income Tax Expense (Benefit)									62	67	78
Net Income (Loss) Attributable to DTE Energy Company									185	150	146
Investments in equity method investees	11				12				11	12	11
Capital expenditures and acquisitions									530	460	463
Goodwill	743				743				743	743	743
Total Assets	5,717				5,378				5,717	5,378	5,072
Operating Segments | Gas Storage and Pipelines
Segment Reporting Information [Line Items]
Operating Revenues — Utility operations									0	0	0
Operating Revenues — Non-utility operations									501	485	453
Depreciation and amortization									94	82	76
Interest expense									73	68	77
Interest income									(8)	(9)	(14)
Equity in earnings of equity method investees									97	123	90
Income Tax Expense (Benefit)									74	68	(30)
Net Income (Loss) Attributable to DTE Energy Company									204	235	275
Investments in equity method investees	1,685				1,585				1,685	1,585	879
Capital expenditures and acquisitions									2,510	176	137
Goodwill	470				299				470	299	299
Total Assets	4,832				3,161				4,832	3,161	2,594
Effect of the Tax Cuts and Jobs Act of 2017											(115)
Operating Segments | Power and Industrial Projects
Segment Reporting Information [Line Items]
Operating Revenues — Utility operations									0	0	0
Operating Revenues — Non-utility operations									1,560	2,204	2,089
Depreciation and amortization									69	67	72
Interest expense									33	31	29
Interest income									(9)	(9)	(7)
Equity in earnings of equity method investees									14	3	9
Income Tax Expense (Benefit)									(63)	(195)	(195)
Net Income (Loss) Attributable to DTE Energy Company									133	161	138
Investments in equity method investees	130				134				130	134	150
Capital expenditures and acquisitions									54	91	56
Goodwill	26				26				26	26	26
Total Assets	537				495				537	495	593
Effect of the Tax Cuts and Jobs Act of 2017											(21)
Operating Segments | Energy Trading
Segment Reporting Information [Line Items]
Operating Revenues — Utility operations									0	0	0
Operating Revenues — Non-utility operations									4,610	5,557	4,277
Depreciation and amortization									6	5	5
Interest expense									8	6	5
Interest income									(4)	(3)	(2)
Equity in earnings of equity method investees									0	0	0
Income Tax Expense (Benefit)									17	13	49
Net Income (Loss) Attributable to DTE Energy Company									49	39	72
Investments in equity method investees	0				0				0	0	0
Capital expenditures and acquisitions									5	5	7
Goodwill	17				17				17	17	17
Total Assets	798				909				798	909	725
Effect of the Tax Cuts and Jobs Act of 2017											2
Operating Segments | Corporate and Other
Segment Reporting Information [Line Items]
Operating Revenues — Utility operations									0	0	0
Operating Revenues — Non-utility operations									2	3	2
Depreciation and amortization									1	1	1
Interest expense									266	220	192
Interest income									(120)	(104)	(88)
Equity in earnings of equity method investees									(3)	4	0
Income Tax Expense (Benefit)									(75)	(48)	(48)
Net Income (Loss) Attributable to DTE Energy Company									(116)	(129)	(103)
Investments in equity method investees	31				33				31	33	26
Capital expenditures and acquisitions									0	2	13
Goodwill	0				0				0	0	0
Total Assets	7,679				6,153				7,679	6,153	5,324
Effect of the Tax Cuts and Jobs Act of 2017											34
Reclassifications and Eliminations
Segment Reporting Information [Line Items]
Operating Revenues — Utility operations									(68)	(64)	(56)
Operating Revenues — Non-utility operations									(647)	(707)	(648)
Depreciation and amortization									0	0	0
Interest expense									(132)	(119)	(106)
Interest income									132	119	106
Equity in earnings of equity method investees									0	0	0
Income Tax Expense (Benefit)									0	0	0
Net Income (Loss) Attributable to DTE Energy Company									0	0	0
Investments in equity method investees	0				0				0	0	0
Capital expenditures and acquisitions									0	0	0
Goodwill	0				0				0	0	0
Total Assets	$ (2,298)				$ (2,309)				$ (2,298)	$ (2,309)	$ (1,704)

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Dividends declared	$ 714,000,000	$ 653,000,000	$ 602,000,000
Dividends paid	692,000,000	620,000,000	592,000,000
DTE Electric
Related Party Transaction [Line Items]
Other services	5,000,000	4,000,000	4,000,000
Dividends declared	494,000,000	461,000,000	432,000,000
Dividends paid	494,000,000	461,000,000	432,000,000
DTE Electric | Energy sales
Related Party Transaction [Line Items]
Revenues	10,000,000	9,000,000	9,000,000
DTE Electric | Shared capital assets
Related Party Transaction [Line Items]
Revenues	47,000,000	43,000,000	39,000,000
DTE Electric | Fuel and purchased power
Related Party Transaction [Line Items]
Costs	9,000,000	7,000,000	6,000,000
DTE Electric | Other services and interest
Related Party Transaction [Line Items]
Costs	23,000,000	33,000,000	(2,000,000)
DTE Electric | Corporate expenses, net
Related Party Transaction [Line Items]
Costs	372,000,000	377,000,000	370,000,000
DTE Electric | DTE Energy
Related Party Transaction [Line Items]
Dividends declared	494,000,000	461,000,000	432,000,000
Dividends paid	494,000,000	461,000,000	432,000,000
Capital contribution from DTE Energy	180,000,000	325,000,000	100,000,000
DTE Electric | DTE Energy Foundation
Related Party Transaction [Line Items]
Charitable contributions to foundation	$ 0	0	$ 7,000,000
NEXUS | Capacity Lease Agreement | DTE Gas
Related Party Transaction [Line Items]
Term of agreement	15 years
Revenues	$ 32,000,000	6,000,000
NEXUS | Service Agreement | DTE Gas
Related Party Transaction [Line Items]
Term of agreement	15 years
Costs	$ 21,000,000	$ 2,000,000

Supplementary Quarterly Finan_3

Supplementary Quarterly Financial Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Entity Information [Line Items]
Operating Revenues	$ 3,148	$ 3,119	$ 2,888	$ 3,514	$ 3,750	$ 3,550	$ 3,159	$ 3,753	$ 12,669	$ 14,212	$ 12,607
Operating Income	415	450	300	542	332	429	329	504	1,707	1,594	1,711
Net Income	$ 267	$ 319	$ 182	$ 401	$ 191	$ 334	$ 234	$ 361	$ 1,169	$ 1,120	$ 1,134
Basic Earnings per Share (in dollars per share)	$ 1.40	$ 1.74	$ 0.99	$ 2.20	$ 1.05	$ 1.84	$ 1.29	$ 2.01	$ 6.32	$ 6.18	$ 6.32
Diluted Earnings per Share (in dollars per share)	$ 1.40	$ 1.73	$ 0.99	$ 2.19	$ 1.05	$ 1.84	$ 1.29	$ 2	$ 6.31	$ 6.17	$ 6.32
DTE Electric
Entity Information [Line Items]
Operating Revenues	$ 1,280	$ 1,519	$ 1,190	$ 1,235	$ 1,296	$ 1,521	$ 1,276	$ 1,205	$ 5,224	$ 5,298
Operating Income	224	440	223	226	168	444	269	253	1,113	1,134	$ 1,165
Net Income	$ 129	$ 307	$ 133	$ 147	$ 56	$ 305	$ 163	$ 140	$ 716	$ 664	$ 601

Schedule II - Valuation and Q_2

Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for Doubtful Accounts (shown as deduction from Accounts receivable in DTE Energy's Consolidated Statements of Financial Position)
Balance at Beginning of Period	$ 91
Additions:
Balance at End of Period	91	$ 91
DTE Electric
Allowance for Doubtful Accounts (shown as deduction from Accounts receivable in DTE Energy's Consolidated Statements of Financial Position)
Balance at Beginning of Period	53
Additions:
Balance at End of Period	46	53
Allowance for Doubtful Accounts
Allowance for Doubtful Accounts (shown as deduction from Accounts receivable in DTE Energy's Consolidated Statements of Financial Position)
Balance at Beginning of Period	91	49	$ 41
Additions:
Charged to costs and expenses	111	140	80
Charged to other accounts	56	55	26
Deductions	(167)	(153)	(98)
Balance at End of Period	91	91	49
Allowance for Doubtful Accounts | DTE Electric
Allowance for Doubtful Accounts (shown as deduction from Accounts receivable in DTE Energy's Consolidated Statements of Financial Position)
Balance at Beginning of Period	53	31	25
Additions:
Charged to costs and expenses	65	85	55
Charged to other accounts	36	36	14
Deductions	(108)	(99)	(63)
Balance at End of Period	$ 46	$ 53	$ 31

Uncategorized Items - dteenergy

Label	Element	Value
Accounting Standards Update 2016-01 [Member] | DTE Electric [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ 0
Accounting Standards Update 2016-01 [Member] | Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	5,000,000
Accounting Standards Update 2016-01 [Member] | Retained Earnings [Member] | DTE Electric [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	3,000,000
Accounting Standards Update 2016-01 [Member] | AOCI Attributable to Parent [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	(5,000,000)
Accounting Standards Update 2016-01 [Member] | AOCI Attributable to Parent [Member] | DTE Electric [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ (3,000,000)