DTE Energy (DTE) 10-Q 24 Apr 19 2019 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information	3 Months Ended
	Mar. 31, 2019shares
Entity Registrant Name	DTE ENERGY CO
Entity Central Index Key	0000936340
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding	183,212,427
DTE Electric
Entity Registrant Name	DTE ELECTRIC CO
Entity Central Index Key	0000028385
Entity Filer Category	Non-accelerated Filer
Document Type	10-Q
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding	138,632,324

Consolidated Statements of Oper

Consolidated Statements of Operations (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Operating Revenues
Utility operations	$ 1,864	$ 1,740
Non-utility operations	1,650	2,013
Operating Revenues	3,514	3,753
Operating Expenses
Fuel, purchased power, and gas — utility	582	553
Fuel, purchased power, and gas — non-utility	1,385	1,773
Operation and maintenance	591	534
Depreciation and amortization	296	281
Taxes other than income	118	111
Asset (gains) losses and impairments, net	0	(3)
Operating Expenses	2,972	3,249
Operating Income	542	504
Other (Income) and Deductions
Interest expense	152	135
Interest income	(4)	(3)
Non-operating retirement benefits, net	9	9
Other income	(88)	(81)
Other expenses	11	25
Other (Income) and Deductions	80	85
Income Before Income Taxes	462	419
Income Tax Expense	54	68
Net Income	408	351
Less: Net Income (Loss) Attributable to Noncontrolling Interests	7	(10)
Net Income Attributable to DTE Energy Company/DTE Electric Company	$ 401	$ 361
Basic Earnings per Common Share
Net Income Attributable to DTE Energy Company (in dollars per share)	$ 2.20	$ 2.01
Diluted Earnings per Common Share
Net Income Attributable to DTE Energy Company (in dollars per share)	$ 2.19	$ 2
Weighted Average Common Shares Outstanding
Basic (in shares)	182	180
Diluted (in shares)	183	180
DTE Electric
Operating Revenues
Utility operations	$ 1,235	$ 1,205
Operating Expenses
Fuel, purchased power, and gas — utility	346	339
Operation and maintenance	358	320
Depreciation and amortization	221	212
Taxes other than income	84	81
Operating Expenses	1,009	952
Operating Income	226	253
Other (Income) and Deductions
Interest expense	76	68
Interest income	(1)	0
Other income	(33)	(27)
Other expenses	8	25
Other (Income) and Deductions	50	66
Income Before Income Taxes	176	187
Income Tax Expense	29	47
Net Income Attributable to DTE Energy Company/DTE Electric Company	$ 147	$ 140

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Net Income	$ 408	$ 351
Net Income	401	361
Other comprehensive income (loss), net of tax:
Benefit obligations, net of taxes of $1 and $1, respectively	4	2
Net unrealized losses on derivatives during the period, net of taxes of $(1) and $—, respectively	(3)	0
Foreign currency translation	1	0
Other comprehensive income	2	2
Comprehensive income	410	353
Less: Comprehensive income (loss) attributable to noncontrolling interests	7	(10)
Comprehensive Income Attributable to DTE Energy Company/DTE Electric Company	403	363
DTE Electric
Net Income	147	140
Other comprehensive income (loss), net of tax:
Other comprehensive income	0	0
Comprehensive Income Attributable to DTE Energy Company/DTE Electric Company	$ 147	$ 140

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income (Unaudited) (Parentheticals) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Tax effect on benefit obligation	$ 1	$ 1
Tax effect on net unrealized gains on investments during the period	$ (1)	$ 0

Consolidated Statements of Fina

Consolidated Statements of Financial Position (Unaudited) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Current Assets
Cash and cash equivalents	$ 56	$ 71
Restricted cash	5	5
Accounts receivable (less allowance for doubtful accounts)
Customer	1,683	1,789
Other	72	108
Inventories
Fuel and gas	195	406
Materials and supplies	409	405
Notes receivable
Derivative assets	72	102
Regulatory assets	117	153
Other	231	221
Total Current Assets	2,840	3,260
Investments
Nuclear decommissioning trust funds	1,509	1,378
Investments in equity method investees	1,772	1,771
Other	238	219
Total Investments	3,519	3,368
Property
Property, plant, and equipment	32,214	31,810
Accumulated depreciation and amortization	(10,350)	(10,160)
Property, plant, and equipment, net	21,864	21,650
Other Assets
Goodwill	2,293	2,293
Regulatory assets	4,520	4,568
Intangible assets	846	849
Notes receivable	158	64
Derivative assets	22	31
Prepaid postretirement costs	76	45
Operating lease right-of-use assets	138
Other	158	160
Total Other Assets	8,211	8,010
Total Assets	36,434	36,288
Accounts payable
Accounts payable	981	1,329
Accrued interest	149	127
Dividends payable	173	172
Short-term borrowings	156	609
Current portion long-term debt, including finance leases	1,499	1,499
Derivative liabilities	50	67
Gas inventory equalization	88	0
Regulatory liabilities	95	126
Short-term borrowings
Operating lease liabilities	33
Other	423	509
Total Current Liabilities	3,647	4,438
Long-Term Debt (net of current portion)
Mortgage bonds, notes, and other	11,624	10,982
Junior subordinated debentures	1,146	1,145
Finance lease liabilities	6	7
Total Long-Term Debt (net of current portion)	12,776	12,134
Other Liabilities
Deferred income taxes	2,029	1,975
Regulatory liabilities	2,895	2,922
Asset retirement obligations	2,500	2,469
Unamortized investment tax credit	137	138
Derivative liabilities	52	89
Accrued pension liability	722	837
Nuclear decommissioning	224	205
Operating lease liabilities	98
Other	334	364
Total Other Liabilities	8,991	8,999
Commitments and Contingencies (Notes 5 and 12)
Equity
Common stock	4,324	4,245
Retained earnings	6,364	6,112
Accumulated other comprehensive loss	(143)	(120)
Total DTE Energy/DTE Electric Company Equity	10,545	10,237
Noncontrolling interests	475	480
Total Equity	11,020	10,717
Total Liabilities and Equity	36,434	36,288
DTE Electric
Current Assets
Cash and cash equivalents	10	18
Accounts receivable (less allowance for doubtful accounts)
Customer	728	750
Affiliates	15	11
Other	25	54
Inventories
Fuel and gas	116	171
Materials and supplies	283	279
Notes receivable
Affiliates	83	0
Other	13	6
Regulatory assets	102	148
Prepaid property tax	87	47
Other	27	36
Total Current Assets	1,489	1,520
Investments
Nuclear decommissioning trust funds	1,509	1,378
Other	35	34
Total Investments	1,544	1,412
Property
Property, plant, and equipment	23,100	22,747
Accumulated depreciation and amortization	(7,442)	(7,310)
Property, plant, and equipment, net	15,658	15,437
Other Assets
Regulatory assets	3,791	3,829
Intangible assets	24	21
Prepaid postretirement costs — affiliates	189	189
Operating lease right-of-use assets	70
Other	135	121
Total Other Assets	4,209	4,160
Total Assets	22,900	22,529
Accounts payable
Affiliates	71	71
Other	363	441
Accrued interest	81	74
Accrued vacation	44	41
Current portion long-term debt, including finance leases	4	4
Regulatory liabilities	87	98
Short-term borrowings
Affiliates	51	101
Other	0	149
Operating lease liabilities	14
Other	101	98
Total Current Liabilities	816	1,077
Long-Term Debt (net of current portion)
Mortgage bonds, notes, and other	7,178	6,538
Finance lease liabilities	6	7
Total Long-Term Debt (net of current portion)	7,184	6,545
Other Liabilities
Deferred income taxes	2,276	2,246
Regulatory liabilities	2,142	2,171
Asset retirement obligations	2,299	2,271
Unamortized investment tax credit	136	137
Nuclear decommissioning	224	205
Accrued pension liability — affiliates	615	718
Accrued postretirement liability — affiliates	257	278
Operating lease liabilities	50
Other	85	88
Total Other Liabilities	8,084	8,114
Commitments and Contingencies (Notes 5 and 12)
Equity
Common stock	4,631	4,631
Retained earnings	2,185	2,162
Total DTE Energy/DTE Electric Company Equity	6,816	6,793
Total Liabilities and Equity	$ 22,900	$ 22,529

Consolidated Statements of Fi_2

Consolidated Statements of Financial Position (Unaudited) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Allowance for doubtful accounts	$ 91	$ 91
Shareholder’s Equity
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares issued (in shares)	183,212,427	181,925,281
Common stock, shares outstanding (in shares)	183,212,427	181,925,281
DTE Electric
Allowance for doubtful accounts	$ 49	$ 53
Shareholder’s Equity
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 (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Operating Activities
Net Income	$ 408	$ 351
Net Income	401	361
Adjustments to reconcile Net Income to Net cash from operating activities:
Depreciation and amortization	296	281
Nuclear fuel amortization	15	15
Allowance for equity funds used during construction	(7)	(7)
Deferred income taxes	49	60
Equity earnings of equity method investees	(23)	(21)
Dividends from equity method investees	44	15
Changes in assets and liabilities:
Accounts receivable, net	143	33
Inventories	207	182
Prepaid postretirement benefit costs	(31)	0
Accounts payable	(288)	(136)
Gas inventory equalization	88	85
Accrued pension liability	(115)	(187)
Accrued postretirement liability	0	(36)
Derivative assets and liabilities	(15)	(7)
Regulatory assets and liabilities	112	148
Other current and noncurrent assets and liabilities	(131)	62
Net cash from operating activities	752	838
Investing Activities
Plant and equipment expenditures — utility	(641)	(466)
Plant and equipment expenditures — non-utility	(27)	(61)
Notes receivable	(48)
Proceeds from sale of nuclear decommissioning trust fund assets	176	336
Investment in nuclear decommissioning trust funds	(178)	(337)
Distributions from equity method investees	1	4
Contributions to equity method investees	(22)	(64)
Notes receivable		3
Other	(9)	(1)
Net cash used for investing activities	(748)	(586)
Financing Activities
Issuance of long-term debt, net of issuance costs	644	0
Short-term borrowings, net	(453)
Short-term borrowings, net		14
Dividends paid on common stock	(172)	(158)
Contributions from noncontrolling interest, principally REF entities	9	12
Distributions to noncontrolling interests	(21)	(4)
Other	(26)	(19)
Net cash from (used for) financing activities	(19)	(155)
Net Increase (Decrease) in Cash, Cash Equivalents, and Restricted Cash	(15)	97
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	76	89
Cash, Cash Equivalents, and Restricted Cash at End of Period	61	186
Supplemental disclosure of non-cash investing and financing activities
Plant and equipment expenditures in accounts payable	235	179
DTE Electric
Operating Activities
Net Income	147	140
Adjustments to reconcile Net Income to Net cash from operating activities:
Depreciation and amortization	221	212
Nuclear fuel amortization	15	15
Allowance for equity funds used during construction	(6)	(5)
Deferred income taxes	23	48
Changes in assets and liabilities:
Accounts receivable, net	47	39
Inventories	51	50
Accounts payable	(36)	(30)
Accrued pension liability — affiliates	(103)	(178)
Accrued postretirement liability — affiliates	(21)	(24)
Regulatory assets and liabilities	130	97
Other current and noncurrent assets and liabilities	(146)	(41)
Net cash from operating activities	322	323
Investing Activities
Plant and equipment expenditures	(531)	(370)
Notes receivable	(96)	0
Proceeds from sale of nuclear decommissioning trust fund assets	176	336
Investment in nuclear decommissioning trust funds	(178)	(337)
Other	(10)	0
Net cash used for investing activities	(639)	(371)
Financing Activities
Issuance of long-term debt, net of issuance costs	644	0
Short-term borrowings, net — affiliate	(50)	26
Short-term borrowings, net — other	(149)	142
Dividends paid on common stock	(124)	(115)
Other	(12)	(4)
Net cash from (used for) financing activities	309	49
Net Increase (Decrease) in Cash, Cash Equivalents, and Restricted Cash	(8)	1
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	18	15
Cash, Cash Equivalents, and Restricted Cash at End of Period	10	16
Supplemental disclosure of non-cash investing and financing activities
Plant and equipment expenditures in accounts payable	$ 140	$ 109

Consolidated Statements of Chan

Consolidated Statements of Changes in Equity (Unaudited) - 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, 2017		179,387,000					138,632,000
Beginning Balance at Dec. 31, 2017	$ 9,990	$ 3,989	$ 5,643	$ (120)	$ 478
Beginning Balance at Dec. 31, 2017						$ 6,265	$ 1,386	$ 2,920	$ 1,956	$ 3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	361					140			140
Net Income (Loss)	351		361		(10)
Dividends declared on common stock	(160)		(160)			(115)			(115)
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	2			2		0
Stock-based compensation, net contributions from noncontrolling interests, and other (in shares)		345,000
Stock-based compensation, net contributions from noncontrolling interests, and other	5	$ (1)	(1)		7
Ending Balance (in shares) at Mar. 31, 2018		181,483,000					138,632,000
Ending Balance at Mar. 31, 2018	$ 10,363	$ 4,163	5,848	(123)	475
Ending Balance at Mar. 31, 2018						$ 6,290	$ 1,386	2,920	1,984	$ 0
Beginning Balance (in shares) at Dec. 31, 2018	181,925,281	181,925,000				138,632,324	138,632,000
Beginning Balance at Dec. 31, 2018	$ 10,717	$ 4,245	6,112	(120)	480
Beginning Balance at Dec. 31, 2018	10,237					$ 6,793	$ 1,386	3,245	2,162
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	401					147			147
Net Income (Loss)	408		401		7
Dividends declared on common stock	(173)		(173)			(124)			(124)
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	2			2		$ 0
Stock-based compensation, net contributions from noncontrolling interests, and other (in shares)		472,000
Stock-based compensation, net contributions from noncontrolling interests, and other	$ (34)	$ (21)	(1)		(12)
Ending Balance (in shares) at Mar. 31, 2019	183,212,427	183,212,000				138,632,324	138,632,000
Ending Balance at Mar. 31, 2019	$ 11,020	$ 4,324	$ 6,364	$ (143)	$ 475
Ending Balance at Mar. 31, 2019	$ 10,545					$ 6,816	$ 1,386	$ 3,245	$ 2,185

Consolidated Statements of Ch_2

Consolidated Statements of Changes in Equity (Unaudited) (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Stockholders' Equity [Abstract]
Dividends declared on common stock (in dollars per share)	$ 0.945	$ 0.88

Organization and Basis of Prese

Organization and Basis of Presentation	3 Months Ended
	Mar. 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 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 MDEQ, and for DTE Energy, the CFTC. Basis of Presentation The Consolidated Financial Statements should be read in conjunction with the Combined Notes to Consolidated Financial Statements included in the combined DTE Energy and DTE Electric 2018 Annual Report on Form 10-K. 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 Consolidated Financial Statements are unaudited but, in the Registrants' opinions, include all adjustments necessary to present a fair statement of the results for the interim periods. All adjustments are of a normal recurring nature, except as otherwise disclosed in these Consolidated Financial Statements and Combined Notes to Consolidated Financial Statements. Financial results for this interim period are not necessarily indicative of results that may be expected for any other interim period or for the fiscal year ending December 31, 2019 . 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 owns a 55% 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 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 March 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 March 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 significant 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 significant 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 12 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 12 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 March 31, 2019 and December 31, 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: March 31, 2019 December 31, 2018 SGG (a) Other Total SGG (a) Other Total (In millions) ASSETS Cash and cash equivalents $ 21 $ 14 $ 35 $ 25 $ 14 $ 39 Restricted cash — 5 5 — 5 5 Accounts receivable 10 28 38 9 37 46 Inventories — 47 47 1 92 93 Property, plant, and equipment, net 394 42 436 395 46 441 Goodwill 25 — 25 25 — 25 Intangible assets 553 — 553 557 — 557 Other current and long-term assets 1 — 1 3 — 3 $ 1,004 $ 136 $ 1,140 $ 1,015 $ 194 $ 1,209 LIABILITIES Accounts payable and accrued current liabilities $ 1 $ 22 $ 23 $ 3 $ 31 $ 34 Other current and long-term liabilities 8 10 18 9 10 19 $ 9 $ 32 $ 41 $ 12 $ 41 $ 53 _____________________________________ (a) Amounts shown are 100% of SGG's assets and liabilities, of which DTE Energy owns 55% . Amounts for DTE Energy's non-consolidated VIEs are as follows: March 31, 2019 December 31, 2018 (In millions) Investments in equity method investees $ 1,412 $ 1,425 Notes receivable $ 26 $ 15 Future funding commitments $ 64 $ 55

Significant Accounting Policies

Significant Accounting Policies	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Significant Accounting Policies	SIGNIFICANT ACCOUNTING POLICIES Other Income The following is a summary of DTE Energy's Other income: Three Months Ended March 31, 2019 2018 (In millions) Income from REF entities $ 27 $ 23 Equity earnings of equity method investees 23 21 Gains from equity securities 17 — Contract services 8 20 Allowance for equity funds used during construction 7 7 Other 6 10 $ 88 $ 81 The following is a summary of DTE Electric's Other income: Three Months Ended March 31, 2019 2018 (In millions) Gains from equity securities allocated from DTE Energy $ 17 $ — Contract services 8 20 Allowance for equity funds used during construction 6 5 Other 2 2 $ 33 $ 27 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 three months ended March 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. Income Taxes The 2019 estimated annual effective tax rates for DTE Energy and DTE Electric are 12% and 16% , respectively. These tax rates are affected by estimated annual permanent items, including AFUDC equity, production tax credits, and other flow-through items, as well as discrete items that may occur in any given period, but are not consistent from period to period. The interim effective tax rate of the Registrants are as follows: Effective Tax Rate Three Months Ended March 31, 2019 2018 DTE Energy 12 % 16 % DTE Electric 16 % 25 % The 4% decrease in DTE Energy's effective tax rate for the three months ended March 31, 2019 was primarily due to the amortization of the TCJA regulatory liability of 3% in 2019 and the remeasurement of deferred taxes in 2018 of $21 million that impacted the effective tax rate by 5% . The decrease in the effective tax rate was partially offset by lower production tax credits of 5% in 2019. The 9% decrease in DTE Electric's effective tax rate for the three months ended March 31, 2019 was primarily due to the amortization of the TCJA regulatory liability of 4% and higher production tax credits of 1% in 2019. The remeasurement of deferred taxes in 2018 of $8 million impacted the effective tax rate by 4% . DTE Energy's total amount of unrecognized tax benefits as of March 31, 2019 was $8 million , which if recognized, would favorably impact its effective tax rate. DTE Electric's total amount of unrecognized tax benefits as of March 31, 2019 was $10 million , which if recognized, would favorably impact its effective tax rate. The Registrants do not anticipate any material changes to the unrecognized tax benefits in the next twelve months. DTE Electric had income tax receivables of $3 million with DTE Energy at March 31, 2019 and income tax receivables with DTE Energy of $8 million at December 31, 2018 . Unrecognized Compensation Costs As of March 31, 2019 , DTE Energy had $121 million of total unrecognized compensation cost related to non-vested stock incentive plan arrangements. That cost is expected to be recognized over a weighted-average period of 1.77 years . Allocated Stock-Based Compensation DTE Electric received an allocation of costs from DTE Energy associated with stock-based compensation of $13 million and $9 million for the three months ended March 31, 2019 and 2018, respectively . 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.

New Accounting Pronouncements

New Accounting Pronouncements	3 Months Ended
	Mar. 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-of-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 11 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 from 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 . 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 to inform credit loss estimates. 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. Early adoption is permitted. 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. Early adoption is permitted. 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 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. Early adoption is permitted. The Registrants 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. Early adoption is permitted. The Registrants are currently assessing the impact of this standard on their Consolidated Financial Statements.

Revenue

Revenue	3 Months Ended
	Mar. 31, 2019
Revenue from Contract with Customer [Abstract]
Revenue	REVENUE Disaggregation of Revenue The following is a summary of revenues disaggregated by segment for DTE Energy: Three Months Ended March 31, 2019 2018 (In millions) Electric (a) Residential $ 553 $ 586 Commercial 421 429 Industrial 163 176 Other (b) 98 14 Total Electric operating revenues (c) $ 1,235 $ 1,205 Gas Gas sales $ 477 $ 457 End User Transportation 81 85 Intermediate Transportation 26 18 Other (d) 61 (10 ) Total Gas operating revenues (e) $ 645 $ 550 Other segment operating revenues Gas Storage and Pipelines (f) $ 116 $ 119 Power and Industrial Projects (g) $ 388 $ 567 Energy Trading (h) $ 1,301 $ 1,498 _______________________________________ (a) Revenues under the Electric segment generally represent those of DTE Electric. (b) Includes a reduction of $39 million in revenues related to the TCJA rate reduction liability for the three months ended March 31, 2018 . Also includes revenue adjustments related to various regulatory mechanisms. (c) Includes $4 million and $5 million of other revenues outside the scope of Topic 606 for the three months ended March 31, 2019 and 2018 , respectively. (d) Includes a reduction of $32 million in revenues related to the TCJA rate reduction liability for the three months ended March 31, 2018 . Also includes revenue adjustments related to various regulatory mechanisms. (e) Includes $3 million under Alternative Revenue Programs for the three months ended March 31, 2018 and $2 million of other revenues for both periods, which are both outside the scope of Topic 606. (f) Includes revenues outside the scope of Topic 606 primarily related to $2 million of contracts accounted for as leases for the three months ended March 31, 2019 . (g) Includes revenues outside the scope of Topic 606 primarily related to $31 million and $28 million of contracts accounted for as leases for the three months ended March 31, 2019 and 2018 , respectively. (h) Includes revenues outside the scope of Topic 606 primarily related to $926 million and $1.2 billion of derivatives for the three months ended March 31, 2019 and 2018 , respectively. 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 17 Revenue recognized that was included in the deferred revenue balance at the beginning of the period (16 ) Ending Balance, March 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) 2019 $ 43 2020 3 2021 5 2022 7 2023 6 2024 and thereafter 11 $ 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) 2019 $ 173 $ 6 2020 295 — 2021 240 — 2022 188 — 2023 134 — 2024 and thereafter 656 — $ 1,686 $ 6 Other Matters DTE Energy has recognized charges of $29 million and $25 million related to expense recognized for estimated uncollectible accounts receivable for the three months ended March 31, 2019 and 2018 , respectively. DTE Electric has recognized charges of $16 million and $14 million related to expense recognized for estimated uncollectible accounts receivable for the three months ended March 31, 2019 and 2018 , respectively.

Regulatory Matters

Regulatory Matters	3 Months Ended
	Mar. 31, 2019
Public Utilities, General Disclosures [Abstract]
Regulatory Matters	REGULATORY MATTERS 2017 Electric Rate Case Filing DTE Electric filed a rate case with the MPSC on April 19, 2017 requesting an increase in base rates of $231 million based on a projected twelve-month period ending October 31, 2018. On November 1, 2017, DTE Electric self-implemented a base rate increase of $125 million . On April 18, 2018, the MPSC issued an order approving an annual revenue increase of $65.2 million for service rendered on or after May 1, 2018. The MPSC authorized a return on equity of 10.0% . On June 28, 2018, the MPSC issued an order on a rehearing granting in part and denying in part, petitions for rehearings of DTE Electric and other intervenors. As a result, the approved addition to base rates increased from $65.2 million to $74.4 million . In August 2018, DTE Electric filed to refund its customers $26.2 million , inclusive of interest, based on their pro rata share of the revenue collected through the self-implementation surcharge in effect from November 1, 2017 to May 1, 2018. In March 2019, the MPSC approved the self-implementation refund of $27.2 million , including interest. The refund will be effective on a per kilowatt-hour basis for bills rendered May and June 2019. DTE Electric has a refund liability as of March 31, 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 is 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 requests an increase in return on equity from 10.0% to 10.5% and includes projected changes in sales, operation and maintenance expenses, and working capital. In addition, the rate filing requests 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 addressed 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. A final MPSC order in this case is expected in May 2019. 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 will be effective upon a final order in DTE Electric's 2018 rate case filing expected in May 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 revenue requirement by $12 million related to the amortization of deferred tax remeasurement. DTE Electric addressed Calculation C in its general rate case filed July 6, 2018.

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2019
Earnings Per Share [Abstract]
Earnings Per Share	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. The following is a reconciliation of DTE Energy's basic and diluted income per share calculation: Three Months Ended March 31, 2019 2018 (In millions, except per share amounts) Basic Earnings per Share Net Income Attributable to DTE Energy Company $ 401 $ 361 Less: Allocation of earnings to net restricted stock awards 1 1 Net income available to common shareholders — basic $ 400 $ 360 Average number of common shares outstanding — basic 182 180 Basic Earnings per Common Share $ 2.20 $ 2.01 Diluted Earnings per Share Net Income Attributable to DTE Energy Company $ 401 $ 361 Less: Allocation of earnings to net restricted stock awards 1 1 Net income available to common shareholders — diluted $ 400 $ 360 Average number of common shares outstanding — basic 182 180 Incremental shares attributable to: Average dilutive equity units, performance share awards, and stock options 1 — Average number of common shares outstanding — diluted 183 180 Diluted Earnings per Common Share (a) $ 2.19 $ 2.00 _______________________________________ (a) The 2016 Equity Units excluded from the calculation of diluted EPS was approximately 6.6 million for the three months ended March 31, 2018 as the dilutive stock price threshold was not met.

Fair Value

Fair Value	3 Months Ended
	Mar. 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 March 31, 2019 and December 31, 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) : March 31, 2019 December 31, 2018 Level Level Level Other (b) Netting (c) Net Balance Level Level Level Other (b) Netting (c) Net Balance (In millions) Assets Cash equivalents (d) $ 17 $ 2 $ — $ — $ — $ 19 $ 16 $ 2 $ — $ — $ — $ 18 Nuclear decommissioning trusts Equity securities 964 — — — — 964 851 — — — — 851 Fixed income securities 13 504 — — — 517 12 490 — — — 502 Private equity and other — — — 23 — 23 — — — 20 — 20 Cash equivalents 5 — — — — 5 5 — — — — 5 Other investments (e) Equity securities 124 — — — — 124 110 — — — — 110 Fixed income securities 72 — — — — 72 69 — — — — 69 Cash equivalents 4 — — — — 4 4 — — — — 4 Other — — — — — — — — — — — — Derivative assets Commodity contracts Natural gas 41 80 57 — (116 ) 62 199 87 63 — (277 ) 72 Electricity — 134 21 — (128 ) 27 — 247 56 — (252 ) 51 Other 2 — 2 — (2 ) 2 — — 7 — (1 ) 6 Foreign currency exchange contracts — 3 — — — 3 — 4 — — — 4 Total derivative assets 43 217 80 — (246 ) 94 199 338 126 — (530 ) 133 Total $ 1,242 $ 723 $ 80 $ 23 $ (246 ) $ 1,822 $ 1,266 $ 830 $ 126 $ 20 $ (530 ) $ 1,712 Liabilities Derivative liabilities Commodity contracts Natural gas $ (42 ) $ (57 ) $ (67 ) $ — $ 107 $ (59 ) $ (197 ) $ (71 ) $ (112 ) $ — $ 272 $ (108 ) Electricity — (119 ) (46 ) — 128 (37 ) — (227 ) (58 ) — 240 (45 ) Other — (1 ) — — 1 — — (1 ) — — 1 — Interest rate contracts — (6 ) — — — (6 ) — (3 ) — — — (3 ) Foreign currency exchange contracts — — — — — — — — — — — — Total derivative liabilities (42 ) (183 ) (113 ) — 236 (102 ) (197 ) (302 ) (170 ) — 513 (156 ) Total $ (42 ) $ (183 ) $ (113 ) $ — $ 236 $ (102 ) $ (197 ) $ (302 ) $ (170 ) $ — $ 513 $ (156 ) Net Assets (Liabilities) at end of period $ 1,200 $ 540 $ (33 ) $ 23 $ (10 ) $ 1,720 $ 1,069 $ 528 $ (44 ) $ 20 $ (17 ) $ 1,556 Assets Current $ 57 $ 167 $ 61 $ — $ (194 ) $ 91 $ 212 $ 273 $ 96 $ — $ (461 ) $ 120 Noncurrent 1,185 556 19 23 (52 ) 1,731 1,054 557 30 20 (69 ) 1,592 Total Assets $ 1,242 $ 723 $ 80 $ 23 $ (246 ) $ 1,822 $ 1,266 $ 830 $ 126 $ 20 $ (530 ) $ 1,712 Liabilities Current $ (37 ) $ (147 ) $ (53 ) $ — $ 187 $ (50 ) $ (191 ) $ (251 ) $ (76 ) $ — $ 451 $ (67 ) Noncurrent (5 ) (36 ) (60 ) — 49 (52 ) (6 ) (51 ) (94 ) — 62 (89 ) Total Liabilities $ (42 ) $ (183 ) $ (113 ) $ — $ 236 $ (102 ) $ (197 ) $ (302 ) $ (170 ) $ — $ 513 $ (156 ) Net Assets (Liabilities) at end of period $ 1,200 $ 540 $ (33 ) $ 23 $ (10 ) $ 1,720 $ 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 March 31, 2019 , the $19 million consisted of $4 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. 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: March 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) $ 8 $ 2 $ — $ — $ 10 $ 8 $ 2 $ — $ — $ 10 Nuclear decommissioning trusts Equity securities 964 — — — 964 851 — — — 851 Fixed income securities 13 504 — — 517 12 490 — — 502 Private equity and other — — — 23 23 — — — 20 20 Cash equivalents 5 — — — 5 5 — — — 5 Other investments Equity securities 11 — — — 11 10 — — — 10 Derivative assets — FTRs — — 2 — 2 — — 6 — 6 Total $ 1,001 $ 506 $ 2 $ 23 $ 1,532 $ 886 $ 492 $ 6 $ 20 $ 1,404 Assets Current $ 8 $ 2 $ 2 $ — $ 12 $ 8 $ 2 $ 6 $ — $ 16 Noncurrent 993 504 — 23 1,520 878 490 — 20 1,388 Total Assets $ 1,001 $ 506 $ 2 $ 23 $ 1,532 $ 886 $ 492 $ 6 $ 20 $ 1,404 _______________________________________ (a) Amounts represent assets valued at NAV as a practical expedient for fair value. (b) At March 31, 2019 , the $10 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: Three Months Ended March 31, 2019 Three Months Ended March 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 into Level 3 from Level 2 — — — — — — — — Transfers from Level 3 into Level 2 — — — — (3 ) — — (3 ) Total gains (losses) Included in earnings 31 (31 ) (1 ) (1 ) (70 ) 131 — 61 Recorded in Regulatory liabilities — — (3 ) (3 ) — — — — Purchases, issuances, and settlements Settlements 8 8 (1 ) 15 92 (156 ) (4 ) (68 ) Net Assets (Liabilities) as of March 31 $ (10 ) $ (25 ) $ 2 $ (33 ) $ (10 ) $ (13 ) $ 4 $ (19 ) 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 March 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 $ 16 $ (21 ) $ (1 ) $ (6 ) $ (58 ) $ (10 ) $ — $ (68 ) 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: Three Months Ended March 31, 2019 2018 (In millions) Net Assets as of beginning of period $ 6 $ 9 Change in fair value recorded in Regulatory liabilities (3 ) — Purchases, issuances, and settlements Settlements (1 ) (4 ) Net Assets as of March 31 $ 2 $ 5 The amount of total gains (losses) included in Regulatory liabilities attributed to the change in unrealized gains (losses) related to assets held at March 31, 2019 and 2018 and reflected in DTE Electric's Consolidated Statements of Financial Position $ — $ 3 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 three months ended March 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: March 31, 2019 Commodity Contracts Derivative Assets Derivative Liabilities Valuation Techniques Unobservable Input Range Weighted Average (In millions) Natural Gas $ 57 $ (67 ) Discounted Cash Flow Forward basis price (per MMBtu) $ (0.88 ) — $ 5.97 /MMBtu $ (0.07 )/MMBtu Electricity $ 21 $ (46 ) Discounted Cash Flow Forward basis price (per MWh) $ (7 ) — $ 7 /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: March 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 (a) , excluding lessor finance leases $ 143 $ — $ — $ 143 $ 40 $ — $ — $ 40 Dividends payable $ 173 $ 173 $ — $ — $ 172 $ 172 $ — $ — Short-term borrowings $ 156 $ — $ 156 $ — $ 609 $ — $ 609 $ — Notes payable — Other (b) , excluding lessee finance leases $ 30 $ — $ — $ 30 $ 41 $ — $ — $ 41 Long-term debt (c) $ 14,265 $ 1,960 $ 11,615 $ 1,431 $ 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: March 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 (a) , excluding lessor finance leases $ 18 $ — $ — $ 18 $ 6 $ — $ — $ 6 Notes receivable — affiliates $ 83 $ — $ — $ 83 $ — $ — $ — $ — Short-term borrowings — affiliates $ 51 $ — $ — $ 51 $ 101 $ — $ — $ 101 Short-term borrowings — other $ — $ — $ — $ — $ 149 $ — $ 149 $ — Notes payable — Other (b) , excluding lessee finance leases $ 23 $ — $ — $ 23 $ 21 $ — $ — $ 21 Long-term debt (c) $ 7,178 $ — $ 7,124 $ 491 $ 6,538 $ — $ 6,552 $ 161 _______________________________________ (a) Noncurrent portion included in Other Assets — Other on DTE Energy'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 8 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. The following table summarizes DTE Electric's fair value of the nuclear decommissioning trust fund assets: March 31, 2019 December 31, 2018 (In millions) Fermi 2 $ 1,502 $ 1,372 Fermi 1 3 3 Low-level radioactive waste 4 3 $ 1,509 $ 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: Three Months Ended March 31, 2019 2018 (In millions) Realized gains $ 11 $ 23 Realized losses $ (7 ) $ (9 ) Proceeds from sale of securities $ 176 $ 336 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: March 31, 2019 December 31, 2018 Fair Unrealized Unrealized Fair Unrealized Unrealized (In millions) Equity securities $ 964 $ 313 $ (51 ) $ 851 $ 235 $ (79 ) Fixed income securities 517 13 (3 ) 502 7 (8 ) Private equity and other 23 — — 20 — — Cash equivalents 5 — — 5 — — $ 1,509 $ 326 $ (54 ) $ 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: March 31, 2019 (In millions) Due within one year $ 26 Due after one through five years 96 Due after five through ten years 109 Due after ten years 286 $ 517 Other Securities At March 31, 2019 and December 31, 2018 , the Registrants' securities, included in Other investments on the Consolidated Statements of Financial Position, were comprised primarily of money market and equity securities. For the three months ended March 31, 2019 , gains related to equity securities were $17 million and losses related to equity securities held at March 31, 2018 were $3 million for the Registrants. 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	3 Months Ended
	Mar. 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 portion of the derivative gain or loss that is effective in offsetting the change in the value of the underlying exposure is deferred in Accumulated other comprehensive income (loss) and later reclassified into earnings when the underlying transaction occurs. Gains or losses from the ineffective portion of cash flow hedges are recognized in earnings immediately. 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 coal forwards, futures, options, swaps, and foreign currency exchange contracts. Items not classified as derivatives include natural gas inventory, pipeline transportation contracts, renewable energy credits, 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 and sells storage and transportation 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 March 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: March 31, 2019 December 31, 2018 Derivative Derivative Liabilities Derivative Derivative Liabilities (In millions) Derivatives designated as hedging instruments Interest rate contracts $ — $ (6 ) $ — $ (3 ) Derivatives not designated as hedging instruments Commodity contracts Natural gas $ 178 $ (166 ) $ 349 $ (380 ) Electricity 155 (165 ) 303 (285 ) Other 4 (1 ) 7 (1 ) Foreign currency exchange contracts 3 — 4 — Total derivatives not designated as hedging instruments $ 340 $ (332 ) $ 663 $ (666 ) Current $ 266 $ (237 ) $ 563 $ (518 ) Noncurrent 74 (101 ) 100 (151 ) Total derivatives $ 340 $ (338 ) $ 663 $ (669 ) The following table presents the fair value of derivative instruments for DTE Electric: March 31, 2019 December 31, 2018 (In millions) FTRs — Other current assets $ 2 $ 6 Total derivatives not designated as hedging instruments $ 2 $ 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 $4 million outstanding at March 31, 2019 and 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 $8 million at March 31, 2019 and December 31, 2018 . 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: March 31, 2019 December 31, 2018 (In millions) Cash collateral netted against Derivative assets $ (10 ) $ (17 ) Cash collateral recorded in Accounts receivable (a) 10 10 Cash collateral recorded in Accounts payable (a) (6 ) (6 ) Total net cash collateral posted (received) $ (6 ) $ (13 ) _______________________________________ (a) Amounts are recorded net by counterparty. The following table presents the netting offsets of Derivative assets and liabilities for DTE Energy: March 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 $ 178 $ (116 ) $ 62 $ 349 $ (277 ) $ 72 Electricity 155 (128 ) 27 303 (252 ) 51 Other 4 (2 ) 2 7 (1 ) 6 Foreign currency exchange contracts 3 — 3 4 — 4 Total derivative assets $ 340 $ (246 ) $ 94 $ 663 $ (530 ) $ 133 Derivative liabilities Commodity contracts Natural gas $ (166 ) $ 107 $ (59 ) $ (380 ) $ 272 $ (108 ) Electricity (165 ) 128 (37 ) (285 ) 240 (45 ) Other (1 ) 1 — (1 ) 1 — Interest rate contracts (6 ) — (6 ) (3 ) — (3 ) Total derivative liabilities $ (338 ) $ 236 $ (102 ) $ (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: March 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 $ 266 $ 74 $ (237 ) $ (101 ) $ 563 $ 100 $ (518 ) $ (151 ) Counterparty netting (187 ) (49 ) 187 49 (451 ) (62 ) 451 62 Collateral adjustment (7 ) (3 ) — — (10 ) (7 ) — — Total derivatives as reported $ 72 $ 22 $ (50 ) $ (52 ) $ 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 the Three Months Ended March 31, 2019 2018 (In millions) Commodity contracts Natural gas Operating Revenues — Non-utility operations $ (15 ) $ (110 ) Natural gas Fuel, purchased power, and gas — non-utility 70 52 Electricity Operating Revenues — Non-utility operations (49 ) 129 Other Operating Revenues — Non-utility operations 1 (1 ) Foreign currency exchange contracts Operating Revenues — Non-utility operations (1 ) 2 Total $ 6 $ 72 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 March 31, 2019 : Commodity Number of Units Natural gas (MMBtu) 2,537,411,045 Electricity (MWh) 33,565,053 Foreign currency exchange (Canadian dollars) 97,013,854 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 March 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 $537 million . As of March 31, 2019 , DTE Energy had $263 million of derivatives in net liability positions, for which hard triggers exist. There is $1 million of 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 $222 million . The net remaining amount of $40 million is derived from the $537 million noted above.

Long-Term Debt

Long-Term Debt	3 Months Ended
	Mar. 31, 2019
Debt Disclosure [Abstract]
Long-Term Debt	LONG-TERM DEBT 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 $ 650 _______________________________________ (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.

Short-Term Credit Arrangements

Short-Term Credit Arrangements and Borrowings	3 Months Ended
	Mar. 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 capital 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 March 31, 2019 , the total funded debt to total capitalization ratios for DTE Energy, DTE Electric, and DTE Gas were 0.55 to 1, 0.51 to 1, and 0.46 to 1, respectively, and were in compliance with this financial covenant. The availability under the facilities in place at March 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 September 2019 70 — — 70 Unsecured revolving credit facility, expiring April 2022 1,200 400 300 1,900 1,420 400 300 2,120 Amounts outstanding at March 31, 2019 Commercial paper issuances 77 — 79 156 Letters of credit 195 — — 195 272 — 79 351 Net availability at March 31, 2019 $ 1,148 $ 400 $ 221 $ 1,769 In February 2019, DTE Energy amended its $150 million letter of credit facility. The facility's maturity date was amended from February 2019 to February 2021. In April 2019, DTE Energy, DTE Electric, and DTE Gas entered into a fourth amended and restated five -year unsecured revolving credit agreement. The agreement's expiration was amended from April 2022 to April 2024. As part of this amendment, DTE Energy increased its $1,200 million unsecured revolving credit facility to $1,500 million and DTE Electric increased its $400 million unsecured revolving credit facility to $500 million . 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. 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 March 31, 2019 , the capacity under this facility was $150 million . The amount outstanding under this agreement was $79 million and $93 million at March 31, 2019 and December 31, 2018 , respectively, and was fully offset by the posted collateral.

Leases

Leases	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Leases	LEASES Disclosures related to the three months ended March 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. Prior period disclosures under Topic 840 have been provided on an annual basis. As a result, the disclosures presented under Topic 842 and Topic 840 will not be fully comparable in specific disclosure requirements or time period. 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 and/or evergreen clauses. Where the renewal options or evergreen provisions 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 DTE Energy were as follows: Three months ended March 31, 2019 (In millions) Operating lease cost $ 11 Finance lease cost: Amortization of right-of-use assets 1 Interest of lease liabilities — Total finance lease cost 1 Variable lease cost 5 $ 17 The components of lease cost for DTE Electric were as follows: Three months ended March 31, 2019 (In millions) Operating lease cost $ 4 Finance lease cost: Amortization of right-of-use assets 1 Interest of lease liabilities — Total finance lease cost 1 Variable lease cost — $ 5 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 recorded expense for short-term leases of $2 million and $1 million , respectively, for the period ended March 31, 2019 . Other information related to leases were as follows for the three months ended March 31, DTE Energy DTE Electric 2019 2019 (In millions) Supplemental Cash Flows Information Cash paid for amounts included in the measurement of these liabilities: Operating cash flows from finance leases $ 1 $ 1 Operating cash flows from operating leases $ 10 $ 3 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 11 $ — Weighted Average Remaining Lease Term Operating leases 9.1 years 10.4 years Finance leases 2.7 years 2.7 years Weighted Average Discount Rate Operating leases 3.8% 3.6% Finance leases 3.0% 3.0% The Registrants' future minimum lease payments under leases for remaining periods as of March 31, 2019 were as follows: DTE Energy DTE Electric Operating Leases Finance Leases Operating Leases Finance Leases (In millions) 2019 $ 28 $ 3 $ 12 $ 3 2020 30 4 12 4 2021 22 3 11 3 2022 16 — 7 — 2023 13 — 6 — 2024 and thereafter 50 — 30 — Total future minimum lease payments 159 10 78 10 Imputed interest (28 ) — (14 ) — $ 131 $ 10 $ 64 $ 10 Finance leases reported on the Consolidated Statement of Financial Position were as follows: DTE Energy DTE Electric March 31, 2019 (In millions) Right-of-use assets, within Property, plant, and equipment, net $ 10 $ 10 Current lease liabilities, within Current Liabilities — Other $ 4 $ 4 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 Lessor Topic 842 — DTE Energy leases a portion of its pipeline system to the Vector Pipeline through a 20 -year finance lease contract that expires in 2020, with renewal options extending for five years each. DTE Energy owns a 40% interest in the Vector Pipeline. In addition, DTE Energy has two energy services agreements, of which a portion are accounted for as finance leases. These agreements expire in 2019 and 2026. 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 were as follows: Three months ended March 31, 2019 (In millions) Fixed payments $ 17 Variable payments 27 $ 44 DTE Energy’s minimum future rental revenues under operating leases for remaining periods as of March 31, 2019 were: DTE Energy (In millions) 2019 $ 50 2020 67 2021 65 2022 22 2023 22 2024 and thereafter 216 $ 442 Depreciation expense associated with DTE Energy's property under operating leases was $8 million for the three months ended March 31, 2019 . Property under operating leases for DTE Energy were as follows: DTE Energy March 31, 2019 (In millions) Gross property under operating leases $ 442 Accumulated amortization of property under operating leases $ 154 The components of DTE Energy’s net investment in finance leases for remaining periods were as follows: DTE Energy March 31, 2019 (In millions) 2019 $ 7 2020 9 2021 — 2022 — 2023 — 2024 and thereafter 1 Total minimum future lease receipts 17 Residual value of leased pipeline 40 Less unearned income 8 Net investment in finance lease 49 Less current portion 5 $ 44 Interest income recognized under finance leases was $1 million for the three months ended March 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: 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 expires 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 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 three months ended March 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. Prior period disclosures under Topic 840 have been provided on an annual basis. As a result, the disclosures presented under Topic 842 and Topic 840 will not be fully comparable in specific disclosure requirements or time period. 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 and/or evergreen clauses. Where the renewal options or evergreen provisions 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 DTE Energy were as follows: Three months ended March 31, 2019 (In millions) Operating lease cost $ 11 Finance lease cost: Amortization of right-of-use assets 1 Interest of lease liabilities — Total finance lease cost 1 Variable lease cost 5 $ 17 The components of lease cost for DTE Electric were as follows: Three months ended March 31, 2019 (In millions) Operating lease cost $ 4 Finance lease cost: Amortization of right-of-use assets 1 Interest of lease liabilities — Total finance lease cost 1 Variable lease cost — $ 5 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 recorded expense for short-term leases of $2 million and $1 million , respectively, for the period ended March 31, 2019 . Other information related to leases were as follows for the three months ended March 31, DTE Energy DTE Electric 2019 2019 (In millions) Supplemental Cash Flows Information Cash paid for amounts included in the measurement of these liabilities: Operating cash flows from finance leases $ 1 $ 1 Operating cash flows from operating leases $ 10 $ 3 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 11 $ — Weighted Average Remaining Lease Term Operating leases 9.1 years 10.4 years Finance leases 2.7 years 2.7 years Weighted Average Discount Rate Operating leases 3.8% 3.6% Finance leases 3.0% 3.0% The Registrants' future minimum lease payments under leases for remaining periods as of March 31, 2019 were as follows: DTE Energy DTE Electric Operating Leases Finance Leases Operating Leases Finance Leases (In millions) 2019 $ 28 $ 3 $ 12 $ 3 2020 30 4 12 4 2021 22 3 11 3 2022 16 — 7 — 2023 13 — 6 — 2024 and thereafter 50 — 30 — Total future minimum lease payments 159 10 78 10 Imputed interest (28 ) — (14 ) — $ 131 $ 10 $ 64 $ 10 Finance leases reported on the Consolidated Statement of Financial Position were as follows: DTE Energy DTE Electric March 31, 2019 (In millions) Right-of-use assets, within Property, plant, and equipment, net $ 10 $ 10 Current lease liabilities, within Current Liabilities — Other $ 4 $ 4 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 Lessor Topic 842 — DTE Energy leases a portion of its pipeline system to the Vector Pipeline through a 20 -year finance lease contract that expires in 2020, with renewal options extending for five years each. DTE Energy owns a 40% interest in the Vector Pipeline. In addition, DTE Energy has two energy services agreements, of which a portion are accounted for as finance leases. These agreements expire in 2019 and 2026. 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 were as follows: Three months ended March 31, 2019 (In millions) Fixed payments $ 17 Variable payments 27 $ 44 DTE Energy’s minimum future rental revenues under operating leases for remaining periods as of March 31, 2019 were: DTE Energy (In millions) 2019 $ 50 2020 67 2021 65 2022 22 2023 22 2024 and thereafter 216 $ 442 Depreciation expense associated with DTE Energy's property under operating leases was $8 million for the three months ended March 31, 2019 . Property under operating leases for DTE Energy were as follows: DTE Energy March 31, 2019 (In millions) Gross property under operating leases $ 442 Accumulated amortization of property under operating leases $ 154 The components of DTE Energy’s net investment in finance leases for remaining periods were as follows: DTE Energy March 31, 2019 (In millions) 2019 $ 7 2020 9 2021 — 2022 — 2023 — 2024 and thereafter 1 Total minimum future lease receipts 17 Residual value of leased pipeline 40 Less unearned income 8 Net investment in finance lease 49 Less current portion 5 $ 44 Interest income recognized under finance leases was $1 million for the three months ended March 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: 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 expires 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 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 three months ended March 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. Prior period disclosures under Topic 840 have been provided on an annual basis. As a result, the disclosures presented under Topic 842 and Topic 840 will not be fully comparable in specific disclosure requirements or time period. 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 and/or evergreen clauses. Where the renewal options or evergreen provisions 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 DTE Energy were as follows: Three months ended March 31, 2019 (In millions) Operating lease cost $ 11 Finance lease cost: Amortization of right-of-use assets 1 Interest of lease liabilities — Total finance lease cost 1 Variable lease cost 5 $ 17 The components of lease cost for DTE Electric were as follows: Three months ended March 31, 2019 (In millions) Operating lease cost $ 4 Finance lease cost: Amortization of right-of-use assets 1 Interest of lease liabilities — Total finance lease cost 1 Variable lease cost — $ 5 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 recorded expense for short-term leases of $2 million and $1 million , respectively, for the period ended March 31, 2019 . Other information related to leases were as follows for the three months ended March 31, DTE Energy DTE Electric 2019 2019 (In millions) Supplemental Cash Flows Information Cash paid for amounts included in the measurement of these liabilities: Operating cash flows from finance leases $ 1 $ 1 Operating cash flows from operating leases $ 10 $ 3 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 11 $ — Weighted Average Remaining Lease Term Operating leases 9.1 years 10.4 years Finance leases 2.7 years 2.7 years Weighted Average Discount Rate Operating leases 3.8% 3.6% Finance leases 3.0% 3.0% The Registrants' future minimum lease payments under leases for remaining periods as of March 31, 2019 were as follows: DTE Energy DTE Electric Operating Leases Finance Leases Operating Leases Finance Leases (In millions) 2019 $ 28 $ 3 $ 12 $ 3 2020 30 4 12 4 2021 22 3 11 3 2022 16 — 7 — 2023 13 — 6 — 2024 and thereafter 50 — 30 — Total future minimum lease payments 159 10 78 10 Imputed interest (28 ) — (14 ) — $ 131 $ 10 $ 64 $ 10 Finance leases reported on the Consolidated Statement of Financial Position were as follows: DTE Energy DTE Electric March 31, 2019 (In millions) Right-of-use assets, within Property, plant, and equipment, net $ 10 $ 10 Current lease liabilities, within Current Liabilities — Other $ 4 $ 4 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 Lessor Topic 842 — DTE Energy leases a portion of its pipeline system to the Vector Pipeline through a 20 -year finance lease contract that expires in 2020, with renewal options extending for five years each. DTE Energy owns a 40% interest in the Vector Pipeline. In addition, DTE Energy has two energy services agreements, of which a portion are accounted for as finance leases. These agreements expire in 2019 and 2026. 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 were as follows: Three months ended March 31, 2019 (In millions) Fixed payments $ 17 Variable payments 27 $ 44 DTE Energy’s minimum future rental revenues under operating leases for remaining periods as of March 31, 2019 were: DTE Energy (In millions) 2019 $ 50 2020 67 2021 65 2022 22 2023 22 2024 and thereafter 216 $ 442 Depreciation expense associated with DTE Energy's property under operating leases was $8 million for the three months ended March 31, 2019 . Property under operating leases for DTE Energy were as follows: DTE Energy March 31, 2019 (In millions) Gross property under operating leases $ 442 Accumulated amortization of property under operating leases $ 154 The components of DTE Energy’s net investment in finance leases for remaining periods were as follows: DTE Energy March 31, 2019 (In millions) 2019 $ 7 2020 9 2021 — 2022 — 2023 — 2024 and thereafter 1 Total minimum future lease receipts 17 Residual value of leased pipeline 40 Less unearned income 8 Net investment in finance lease 49 Less current portion 5 $ 44 Interest income recognized under finance leases was $1 million for the three months ended March 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: 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 expires 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 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 three months ended March 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. Prior period disclosures under Topic 840 have been provided on an annual basis. As a result, the disclosures presented under Topic 842 and Topic 840 will not be fully comparable in specific disclosure requirements or time period. 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 and/or evergreen clauses. Where the renewal options or evergreen provisions 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 DTE Energy were as follows: Three months ended March 31, 2019 (In millions) Operating lease cost $ 11 Finance lease cost: Amortization of right-of-use assets 1 Interest of lease liabilities — Total finance lease cost 1 Variable lease cost 5 $ 17 The components of lease cost for DTE Electric were as follows: Three months ended March 31, 2019 (In millions) Operating lease cost $ 4 Finance lease cost: Amortization of right-of-use assets 1 Interest of lease liabilities — Total finance lease cost 1 Variable lease cost — $ 5 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 recorded expense for short-term leases of $2 million and $1 million , respectively, for the period ended March 31, 2019 . Other information related to leases were as follows for the three months ended March 31, DTE Energy DTE Electric 2019 2019 (In millions) Supplemental Cash Flows Information Cash paid for amounts included in the measurement of these liabilities: Operating cash flows from finance leases $ 1 $ 1 Operating cash flows from operating leases $ 10 $ 3 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 11 $ — Weighted Average Remaining Lease Term Operating leases 9.1 years 10.4 years Finance leases 2.7 years 2.7 years Weighted Average Discount Rate Operating leases 3.8% 3.6% Finance leases 3.0% 3.0% The Registrants' future minimum lease payments under leases for remaining periods as of March 31, 2019 were as follows: DTE Energy DTE Electric Operating Leases Finance Leases Operating Leases Finance Leases (In millions) 2019 $ 28 $ 3 $ 12 $ 3 2020 30 4 12 4 2021 22 3 11 3 2022 16 — 7 — 2023 13 — 6 — 2024 and thereafter 50 — 30 — Total future minimum lease payments 159 10 78 10 Imputed interest (28 ) — (14 ) — $ 131 $ 10 $ 64 $ 10 Finance leases reported on the Consolidated Statement of Financial Position were as follows: DTE Energy DTE Electric March 31, 2019 (In millions) Right-of-use assets, within Property, plant, and equipment, net $ 10 $ 10 Current lease liabilities, within Current Liabilities — Other $ 4 $ 4 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 Lessor Topic 842 — DTE Energy leases a portion of its pipeline system to the Vector Pipeline through a 20 -year finance lease contract that expires in 2020, with renewal options extending for five years each. DTE Energy owns a 40% interest in the Vector Pipeline. In addition, DTE Energy has two energy services agreements, of which a portion are accounted for as finance leases. These agreements expire in 2019 and 2026. 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 were as follows: Three months ended March 31, 2019 (In millions) Fixed payments $ 17 Variable payments 27 $ 44 DTE Energy’s minimum future rental revenues under operating leases for remaining periods as of March 31, 2019 were: DTE Energy (In millions) 2019 $ 50 2020 67 2021 65 2022 22 2023 22 2024 and thereafter 216 $ 442 Depreciation expense associated with DTE Energy's property under operating leases was $8 million for the three months ended March 31, 2019 . Property under operating leases for DTE Energy were as follows: DTE Energy March 31, 2019 (In millions) Gross property under operating leases $ 442 Accumulated amortization of property under operating leases $ 154 The components of DTE Energy’s net investment in finance leases for remaining periods were as follows: DTE Energy March 31, 2019 (In millions) 2019 $ 7 2020 9 2021 — 2022 — 2023 — 2024 and thereafter 1 Total minimum future lease receipts 17 Residual value of leased pipeline 40 Less unearned income 8 Net investment in finance lease 49 Less current portion 5 $ 44 Interest income recognized under finance leases was $1 million for the three months ended March 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: 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 expires 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 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	3 Months Ended
	Mar. 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 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 cannot predict the financial impact or outcome of this matter, or the timing of its resolution. 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. In February 2016, the U.S. Supreme Court granted petitioners' requests for a stay of the carbon rules for existing EGUs (also known as the EPA Clean Power Plan) pending final review by the courts. The Clean Power Plan has no legal effect while the stay is in place. On March 28, 2017, a presidential executive order was issued on "Promoting Energy Independence and Economic Growth." The order instructs the EPA to review, and if appropriate, suspend, revise or rescind the Clean Power Plan rule. Following the issuance of this order, the federal government requested the U.S. Court of Appeals for the D.C. Circuit to hold all legal challenges in abeyance until the review of these regulations is completed. On October 10, 2017, the EPA proposed to rescind the Clean Power Plan and in August 2018, the EPA proposed revised emission guidelines for GHGs from existing electric utility generating units. This proposed rule, named the Affordable Clean Energy (ACE) rule, is intended to replace the Clean Power Plan rule. In addition, 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. These proposed rules do not impact DTE Energy's recently revised goal to reduce carbon emissions 32% by the early 2020 s, 50% by 2030 , and 80% by 2040 from the 2005 carbon emissions levels. 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 2018 . DTE Electric does not anticipate additional capital expenditures for air pollution requirements through 2025 . 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 March 31, 2019 and December 31, 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. Additionally, D.C. District Court Decisions on August 21, 2018 and March 19, 2019 may affect the timing of closure of coal ash impoundments that are not lined with an engineered liner system. In 2019, the EPA is expected to affirmatively undertake rulemaking to implement the D.C. District Court's decisions that will 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. The bill provides for a CCR program to be regulated in Michigan once approval is requested and received from the EPA. 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. CCR obligations vary based on plant life, but include the installation of monitoring wells, compliance with groundwater standards, and the closure of landfills and basins at the end of the useful life of the associated power plant or as a basin becomes inactive. Under the current CCR rules and uncertainty regarding the D.C. District Court decision, capital costs and timing associated with the building of new CCR facilities or retirement of existing CCR facilities are being evaluated. 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 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. 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 2019. 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 six of the MGP sites is complete, and the sites are closed. DTE Gas has also completed partial closure of six 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 March 31, 2019 and December 31, 2018 , DTE Gas had $30 million and $25 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 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 environmental 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. 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 the MDEQ 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 process, DTE Energy has worked with the MDEQ to develop air permits reflecting significant SO 2 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 at this time. Michigan's Phase 2 non-attainment area includes DTE Electric facilities in St. Clair County. State implementation plan (SIP) 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 the end of 2019. DTE Energy is currently working with the MDEQ 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 March 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 March 31, 2019 was $380 million . Payments under these guarantees are considered remote. NEXUS Guarantees NEXUS entered into certain 15 -year capacity agreements for the transportation of natural gas with DTE Gas and Texas Eastern Transmission, LP, an unrelated third party. Pursuant to the terms of those agreements, in December 2016, DTE Energy executed separate guarantee agreements with DTE Gas and Texas Eastern Transmission, LP, with maximum potential payments totaling $242 million and $377 million at March 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 also entered into 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 March 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. In conjunction with the execution of an agreement under which NEXUS agreed to purchase Generation Pipeline, LLC, in January 2019, DTE Energy executed a guarantee agreement with the sellers of Generation Pipeline. The maximum potential payment, which represents a portion of the purchase price due and payable by NEXUS at the completion of the closing of the acquisition, totals $15 million at March 31, 2019 . The guarantee terminates upon any of the following events: (i) all NEXUS obligations under the purchase agreement have been paid in full; (ii) the completion of the closing, or (iii) the termination of the purchase agreement by NEXUS in accordance with its terms. 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 $64 million at March 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 March 31, 2019 , DTE Energy had $76 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. Labor Contracts There are several bargaining units for DTE Energy subsidiaries' approximate 5,200 represented employees, including DTE Electric's approximate 2,800 represented employees. The majority of the represented employees are under contracts that expire in 2020 and 2021. Purchase Commitments Utility capital expenditures, expenditures for non-utility businesses, and contributions to equity method investees will be approximately $3.9 billion and $2.2 billion in 2019 for DTE Energy and DTE Electric, respectively. The Registrants have made certain commitments in connection with the estimated 2019 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 March 31, 2019 , PG&E's account is substantially current and DTE Energy determined no reserve was necessary. As of March 31, 2019 , the book value of long-lived assets used in producing electric output for sale to PG&E was approximately $105 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. There were no other new events occurring during the first quarter of 2019 that would negatively impact the assumptions made within the December 31, 2018 impairment analysis. Therefore, no triggering events were identified. 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 5 and 8 to the Consolidated Financial Statements, " Regulatory Matters " and " Financial and Other Derivative Instruments ," respectively.

Retirement Benefits and Trustee

Retirement Benefits and Trusteed Assets	3 Months Ended
	Mar. 31, 2019
Defined Benefit Plan [Abstract]
Retirement Benefits and Trusteed Assets	RETIREMENT BENEFITS AND TRUSTEED ASSETS The following tables detail the components of net periodic benefit costs (credits) for pension benefits and other postretirement benefits for DTE Energy: Pension Benefits Other Postretirement Benefits Three Months Ended March 31, 2019 2018 2019 2018 (In millions) Service cost $ 21 $ 25 $ 5 $ 7 Interest cost 55 50 18 17 Expected return on plan assets (81 ) (82 ) (31 ) (36 ) Amortization of: Net actuarial loss 32 44 3 3 Prior service credit — — (2 ) — Net periodic benefit cost (credit) $ 27 $ 37 $ (7 ) $ (9 ) DTE Electric participates in various plans that provide pension and other postretirement benefits for DTE Energy and its affiliates. The plans are sponsored by DTE Energy's subsidiary, DTE Energy Corporate Services, 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. 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 $23 million and $30 million for the three months ended March 31, 2019 and 2018 , respectively. These amounts include recognized contractual termination benefit charges, curtailment gains, and settlement charges. The following tables detail the components of net periodic benefit costs (credits) for other postretirement benefits for DTE Electric: Other Postretirement Benefits Three Months Ended March 31, 2019 2018 (In millions) Service cost $ 4 $ 5 Interest cost 13 13 Expected return on plan assets (21 ) (24 ) Amortization of: Net actuarial loss 1 2 Prior service credit (1 ) — Net periodic benefit credit $ (4 ) $ (4 ) Pension and Other Postretirement Contributions 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. At the discretion of management and depending upon financial market conditions, DTE Energy anticipates making up to an additional $50 million in contributions to the qualified pension plans in 2019 . DTE Energy does not anticipate making any contributions to the other postretirement benefit plans in 2019 .

Segment and Related Information

Segment and Related Information	3 Months Ended
	Mar. 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: Three Months Ended March 31, 2019 2018 (In millions) Electric $ 14 $ 13 Gas 2 2 Gas Storage and Pipelines 3 8 Power and Industrial Projects 145 155 Energy Trading 7 7 Corporate and Other 1 1 $ 172 $ 186 Financial data of DTE Energy's business segments follows: Three Months Ended March 31, 2019 2018 (In millions) Operating Revenues — Utility operations Electric $ 1,235 $ 1,205 Gas 645 550 Operating Revenues — Non-utility operations Gas Storage and Pipelines 116 119 Power and Industrial Projects 388 567 Energy Trading 1,301 1,498 Corporate and Other 1 — Reconciliation and Eliminations (172 ) (186 ) Total $ 3,514 $ 3,753 Three Months Ended March 31, 2019 2018 (In millions) Net Income (Loss) Attributable to DTE Energy by Segment: Electric $ 147 $ 140 Gas 151 104 Gas Storage and Pipelines 48 62 Power and Industrial Projects 26 45 Energy Trading 32 31 Corporate and Other (3 ) (21 ) Net Income Attributable to DTE Energy Company $ 401 $ 361

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The Consolidated Financial Statements should be read in conjunction with the Combined Notes to Consolidated Financial Statements included in the combined DTE Energy and DTE Electric 2018 Annual Report on Form 10-K. 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 Consolidated Financial Statements are unaudited but, in the Registrants' opinions, include all adjustments necessary to present a fair statement of the results for the interim periods. All adjustments are of a normal recurring nature, except as otherwise disclosed in these Consolidated Financial Statements and Combined Notes to Consolidated Financial Statements. Financial results for this interim period are not necessarily indicative of results that may be expected for any other interim period or for the fiscal year ending December 31, 2019 . 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 owns a 55% 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 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 March 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 March 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 significant 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 significant 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 12 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 12 to the Consolidated Financial Statements, " Commitments and Contingencies ," for further discussion of the NEXUS guarantee arrangements.
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. 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 three months ended March 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.
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.
Recently Adopted and Recently Issued 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-of-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 11 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 from 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 . 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 to inform credit loss estimates. 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. Early adoption is permitted. 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. Early adoption is permitted. 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 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. Early adoption is permitted. The Registrants 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. Early adoption is permitted. The Registrants are currently assessing the impact of this standard on their Consolidated Financial Statements.
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 March 31, 2019 and December 31, 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	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 portion of the derivative gain or loss that is effective in offsetting the change in the value of the underlying exposure is deferred in Accumulated other comprehensive income (loss) and later reclassified into earnings when the underlying transaction occurs. Gains or losses from the ineffective portion of cash flow hedges are recognized in earnings immediately. 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 coal forwards, futures, options, swaps, and foreign currency exchange contracts. Items not classified as derivatives include natural gas inventory, pipeline transportation contracts, renewable energy credits, 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 and sells storage and transportation 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 March 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.
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 $4 million outstanding at March 31, 2019 and 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 $8 million at March 31, 2019 and December 31, 2018 . 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, Derivatives Not Designated or Qualifying as Hedges	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.
Income Tax	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.

Organization and Basis of Pre_2

Organization and Basis of Presentation (Tables)	3 Months Ended
	Mar. 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 March 31, 2019 and December 31, 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: March 31, 2019 December 31, 2018 SGG (a) Other Total SGG (a) Other Total (In millions) ASSETS Cash and cash equivalents $ 21 $ 14 $ 35 $ 25 $ 14 $ 39 Restricted cash — 5 5 — 5 5 Accounts receivable 10 28 38 9 37 46 Inventories — 47 47 1 92 93 Property, plant, and equipment, net 394 42 436 395 46 441 Goodwill 25 — 25 25 — 25 Intangible assets 553 — 553 557 — 557 Other current and long-term assets 1 — 1 3 — 3 $ 1,004 $ 136 $ 1,140 $ 1,015 $ 194 $ 1,209 LIABILITIES Accounts payable and accrued current liabilities $ 1 $ 22 $ 23 $ 3 $ 31 $ 34 Other current and long-term liabilities 8 10 18 9 10 19 $ 9 $ 32 $ 41 $ 12 $ 41 $ 53 _____________________________________ (a) Amounts shown are 100% of SGG's assets and liabilities, of which DTE Energy owns 55% .
Summary of Amounts for Non-Consolidated Variable Interest Entities	Amounts for DTE Energy's non-consolidated VIEs are as follows: March 31, 2019 December 31, 2018 (In millions) Investments in equity method investees $ 1,412 $ 1,425 Notes receivable $ 26 $ 15 Future funding commitments $ 64 $ 55

Significant Accounting Polici_3

Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Schedule of Other Income	The following is a summary of DTE Energy's Other income: Three Months Ended March 31, 2019 2018 (In millions) Income from REF entities $ 27 $ 23 Equity earnings of equity method investees 23 21 Gains from equity securities 17 — Contract services 8 20 Allowance for equity funds used during construction 7 7 Other 6 10 $ 88 $ 81 The following is a summary of DTE Electric's Other income: Three Months Ended March 31, 2019 2018 (In millions) Gains from equity securities allocated from DTE Energy $ 17 $ — Contract services 8 20 Allowance for equity funds used during construction 6 5 Other 2 2 $ 33 $ 27
Schedule of Effective Tax Rate	The interim effective tax rate of the Registrants are as follows: Effective Tax Rate Three Months Ended March 31, 2019 2018 DTE Energy 12 % 16 % DTE Electric 16 % 25 %

Revenue (Tables)

Revenue (Tables)	3 Months Ended
	Mar. 31, 2019
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following is a summary of revenues disaggregated by segment for DTE Energy: Three Months Ended March 31, 2019 2018 (In millions) Electric (a) Residential $ 553 $ 586 Commercial 421 429 Industrial 163 176 Other (b) 98 14 Total Electric operating revenues (c) $ 1,235 $ 1,205 Gas Gas sales $ 477 $ 457 End User Transportation 81 85 Intermediate Transportation 26 18 Other (d) 61 (10 ) Total Gas operating revenues (e) $ 645 $ 550 Other segment operating revenues Gas Storage and Pipelines (f) $ 116 $ 119 Power and Industrial Projects (g) $ 388 $ 567 Energy Trading (h) $ 1,301 $ 1,498 _______________________________________ (a) Revenues under the Electric segment generally represent those of DTE Electric. (b) Includes a reduction of $39 million in revenues related to the TCJA rate reduction liability for the three months ended March 31, 2018 . Also includes revenue adjustments related to various regulatory mechanisms. (c) Includes $4 million and $5 million of other revenues outside the scope of Topic 606 for the three months ended March 31, 2019 and 2018 , respectively. (d) Includes a reduction of $32 million in revenues related to the TCJA rate reduction liability for the three months ended March 31, 2018 . Also includes revenue adjustments related to various regulatory mechanisms. (e) Includes $3 million under Alternative Revenue Programs for the three months ended March 31, 2018 and $2 million of other revenues for both periods, which are both outside the scope of Topic 606. (f) Includes revenues outside the scope of Topic 606 primarily related to $2 million of contracts accounted for as leases for the three months ended March 31, 2019 . (g) Includes revenues outside the scope of Topic 606 primarily related to $31 million and $28 million of contracts accounted for as leases for the three months ended March 31, 2019 and 2018 , respectively. (h) Includes revenues outside the scope of Topic 606 primarily related to $926 million and $1.2 billion of derivatives for the three months ended March 31, 2019 and 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 17 Revenue recognized that was included in the deferred revenue balance at the beginning of the period (16 ) Ending Balance, March 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) 2019 $ 43 2020 3 2021 5 2022 7 2023 6 2024 and thereafter 11 $ 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) 2019 $ 173 $ 6 2020 295 — 2021 240 — 2022 188 — 2023 134 — 2024 and thereafter 656 — $ 1,686 $ 6

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 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: Three Months Ended March 31, 2019 2018 (In millions, except per share amounts) Basic Earnings per Share Net Income Attributable to DTE Energy Company $ 401 $ 361 Less: Allocation of earnings to net restricted stock awards 1 1 Net income available to common shareholders — basic $ 400 $ 360 Average number of common shares outstanding — basic 182 180 Basic Earnings per Common Share $ 2.20 $ 2.01 Diluted Earnings per Share Net Income Attributable to DTE Energy Company $ 401 $ 361 Less: Allocation of earnings to net restricted stock awards 1 1 Net income available to common shareholders — diluted $ 400 $ 360 Average number of common shares outstanding — basic 182 180 Incremental shares attributable to: Average dilutive equity units, performance share awards, and stock options 1 — Average number of common shares outstanding — diluted 183 180 Diluted Earnings per Common Share (a) $ 2.19 $ 2.00 _______________________________________ (a) The 2016 Equity Units excluded from the calculation of diluted EPS was approximately 6.6 million for the three months ended March 31, 2018 as the dilutive stock price threshold was not met.

Fair Value (Tables)

Fair Value (Tables)	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Assets and Liabilities Measured and 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) : March 31, 2019 December 31, 2018 Level Level Level Other (b) Netting (c) Net Balance Level Level Level Other (b) Netting (c) Net Balance (In millions) Assets Cash equivalents (d) $ 17 $ 2 $ — $ — $ — $ 19 $ 16 $ 2 $ — $ — $ — $ 18 Nuclear decommissioning trusts Equity securities 964 — — — — 964 851 — — — — 851 Fixed income securities 13 504 — — — 517 12 490 — — — 502 Private equity and other — — — 23 — 23 — — — 20 — 20 Cash equivalents 5 — — — — 5 5 — — — — 5 Other investments (e) Equity securities 124 — — — — 124 110 — — — — 110 Fixed income securities 72 — — — — 72 69 — — — — 69 Cash equivalents 4 — — — — 4 4 — — — — 4 Other — — — — — — — — — — — — Derivative assets Commodity contracts Natural gas 41 80 57 — (116 ) 62 199 87 63 — (277 ) 72 Electricity — 134 21 — (128 ) 27 — 247 56 — (252 ) 51 Other 2 — 2 — (2 ) 2 — — 7 — (1 ) 6 Foreign currency exchange contracts — 3 — — — 3 — 4 — — — 4 Total derivative assets 43 217 80 — (246 ) 94 199 338 126 — (530 ) 133 Total $ 1,242 $ 723 $ 80 $ 23 $ (246 ) $ 1,822 $ 1,266 $ 830 $ 126 $ 20 $ (530 ) $ 1,712 Liabilities Derivative liabilities Commodity contracts Natural gas $ (42 ) $ (57 ) $ (67 ) $ — $ 107 $ (59 ) $ (197 ) $ (71 ) $ (112 ) $ — $ 272 $ (108 ) Electricity — (119 ) (46 ) — 128 (37 ) — (227 ) (58 ) — 240 (45 ) Other — (1 ) — — 1 — — (1 ) — — 1 — Interest rate contracts — (6 ) — — — (6 ) — (3 ) — — — (3 ) Foreign currency exchange contracts — — — — — — — — — — — — Total derivative liabilities (42 ) (183 ) (113 ) — 236 (102 ) (197 ) (302 ) (170 ) — 513 (156 ) Total $ (42 ) $ (183 ) $ (113 ) $ — $ 236 $ (102 ) $ (197 ) $ (302 ) $ (170 ) $ — $ 513 $ (156 ) Net Assets (Liabilities) at end of period $ 1,200 $ 540 $ (33 ) $ 23 $ (10 ) $ 1,720 $ 1,069 $ 528 $ (44 ) $ 20 $ (17 ) $ 1,556 Assets Current $ 57 $ 167 $ 61 $ — $ (194 ) $ 91 $ 212 $ 273 $ 96 $ — $ (461 ) $ 120 Noncurrent 1,185 556 19 23 (52 ) 1,731 1,054 557 30 20 (69 ) 1,592 Total Assets $ 1,242 $ 723 $ 80 $ 23 $ (246 ) $ 1,822 $ 1,266 $ 830 $ 126 $ 20 $ (530 ) $ 1,712 Liabilities Current $ (37 ) $ (147 ) $ (53 ) $ — $ 187 $ (50 ) $ (191 ) $ (251 ) $ (76 ) $ — $ 451 $ (67 ) Noncurrent (5 ) (36 ) (60 ) — 49 (52 ) (6 ) (51 ) (94 ) — 62 (89 ) Total Liabilities $ (42 ) $ (183 ) $ (113 ) $ — $ 236 $ (102 ) $ (197 ) $ (302 ) $ (170 ) $ — $ 513 $ (156 ) Net Assets (Liabilities) at end of period $ 1,200 $ 540 $ (33 ) $ 23 $ (10 ) $ 1,720 $ 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 March 31, 2019 , the $19 million consisted of $4 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. 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: March 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) $ 8 $ 2 $ — $ — $ 10 $ 8 $ 2 $ — $ — $ 10 Nuclear decommissioning trusts Equity securities 964 — — — 964 851 — — — 851 Fixed income securities 13 504 — — 517 12 490 — — 502 Private equity and other — — — 23 23 — — — 20 20 Cash equivalents 5 — — — 5 5 — — — 5 Other investments Equity securities 11 — — — 11 10 — — — 10 Derivative assets — FTRs — — 2 — 2 — — 6 — 6 Total $ 1,001 $ 506 $ 2 $ 23 $ 1,532 $ 886 $ 492 $ 6 $ 20 $ 1,404 Assets Current $ 8 $ 2 $ 2 $ — $ 12 $ 8 $ 2 $ 6 $ — $ 16 Noncurrent 993 504 — 23 1,520 878 490 — 20 1,388 Total Assets $ 1,001 $ 506 $ 2 $ 23 $ 1,532 $ 886 $ 492 $ 6 $ 20 $ 1,404 _______________________________________ (a) Amounts represent assets valued at NAV as a practical expedient for fair value. (b) At March 31, 2019 , the $10 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.
Reconciliation of Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis	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: Three Months Ended March 31, 2019 Three Months Ended March 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 into Level 3 from Level 2 — — — — — — — — Transfers from Level 3 into Level 2 — — — — (3 ) — — (3 ) Total gains (losses) Included in earnings 31 (31 ) (1 ) (1 ) (70 ) 131 — 61 Recorded in Regulatory liabilities — — (3 ) (3 ) — — — — Purchases, issuances, and settlements Settlements 8 8 (1 ) 15 92 (156 ) (4 ) (68 ) Net Assets (Liabilities) as of March 31 $ (10 ) $ (25 ) $ 2 $ (33 ) $ (10 ) $ (13 ) $ 4 $ (19 ) 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 March 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 $ 16 $ (21 ) $ (1 ) $ (6 ) $ (58 ) $ (10 ) $ — $ (68 ) 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: Three Months Ended March 31, 2019 2018 (In millions) Net Assets as of beginning of period $ 6 $ 9 Change in fair value recorded in Regulatory liabilities (3 ) — Purchases, issuances, and settlements Settlements (1 ) (4 ) Net Assets as of March 31 $ 2 $ 5 The amount of total gains (losses) included in Regulatory liabilities attributed to the change in unrealized gains (losses) related to assets held at March 31, 2019 and 2018 and reflected in DTE Electric's Consolidated Statements of Financial Position $ — $ 3
Unobservable Inputs Related to Level 3 Assets and Liabilities	The following tables present the unobservable inputs related to DTE Energy's Level 3 assets and liabilities: March 31, 2019 Commodity Contracts Derivative Assets Derivative Liabilities Valuation Techniques Unobservable Input Range Weighted Average (In millions) Natural Gas $ 57 $ (67 ) Discounted Cash Flow Forward basis price (per MMBtu) $ (0.88 ) — $ 5.97 /MMBtu $ (0.07 )/MMBtu Electricity $ 21 $ (46 ) Discounted Cash Flow Forward basis price (per MWh) $ (7 ) — $ 7 /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
Carrying Amount of Fair Value of Financial Instruments	The following table presents the carrying amount and fair value of financial instruments for DTE Energy: March 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 (a) , excluding lessor finance leases $ 143 $ — $ — $ 143 $ 40 $ — $ — $ 40 Dividends payable $ 173 $ 173 $ — $ — $ 172 $ 172 $ — $ — Short-term borrowings $ 156 $ — $ 156 $ — $ 609 $ — $ 609 $ — Notes payable — Other (b) , excluding lessee finance leases $ 30 $ — $ — $ 30 $ 41 $ — $ — $ 41 Long-term debt (c) $ 14,265 $ 1,960 $ 11,615 $ 1,431 $ 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: March 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 (a) , excluding lessor finance leases $ 18 $ — $ — $ 18 $ 6 $ — $ — $ 6 Notes receivable — affiliates $ 83 $ — $ — $ 83 $ — $ — $ — $ — Short-term borrowings — affiliates $ 51 $ — $ — $ 51 $ 101 $ — $ — $ 101 Short-term borrowings — other $ — $ — $ — $ — $ 149 $ — $ 149 $ — Notes payable — Other (b) , excluding lessee finance leases $ 23 $ — $ — $ 23 $ 21 $ — $ — $ 21 Long-term debt (c) $ 7,178 $ — $ 7,124 $ 491 $ 6,538 $ — $ 6,552 $ 161 _______________________________________ (a) Noncurrent portion included in Other Assets — Other on DTE Energy'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: March 31, 2019 December 31, 2018 (In millions) Fermi 2 $ 1,502 $ 1,372 Fermi 1 3 3 Low-level radioactive waste 4 3 $ 1,509 $ 1,378
Schedule of Realized Gains and Losses and Proceeds from Sale of Securities by 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: Three Months Ended March 31, 2019 2018 (In millions) Realized gains $ 11 $ 23 Realized losses $ (7 ) $ (9 ) Proceeds from sale of securities $ 176 $ 336
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: March 31, 2019 December 31, 2018 Fair Unrealized Unrealized Fair Unrealized Unrealized (In millions) Equity securities $ 964 $ 313 $ (51 ) $ 851 $ 235 $ (79 ) Fixed income securities 517 13 (3 ) 502 7 (8 ) Private equity and other 23 — — 20 — — Cash equivalents 5 — — 5 — — $ 1,509 $ 326 $ (54 ) $ 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: March 31, 2019 (In millions) Due within one year $ 26 Due after one through five years 96 Due after five through ten years 109 Due after ten years 286 $ 517

Financial and Other Derivativ_2

Financial and Other Derivative Instruments (Tables)	3 Months Ended
	Mar. 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: March 31, 2019 December 31, 2018 Derivative Derivative Liabilities Derivative Derivative Liabilities (In millions) Derivatives designated as hedging instruments Interest rate contracts $ — $ (6 ) $ — $ (3 ) Derivatives not designated as hedging instruments Commodity contracts Natural gas $ 178 $ (166 ) $ 349 $ (380 ) Electricity 155 (165 ) 303 (285 ) Other 4 (1 ) 7 (1 ) Foreign currency exchange contracts 3 — 4 — Total derivatives not designated as hedging instruments $ 340 $ (332 ) $ 663 $ (666 ) Current $ 266 $ (237 ) $ 563 $ (518 ) Noncurrent 74 (101 ) 100 (151 ) Total derivatives $ 340 $ (338 ) $ 663 $ (669 ) The following table presents the fair value of derivative instruments for DTE Electric: March 31, 2019 December 31, 2018 (In millions) FTRs — Other current assets $ 2 $ 6 Total derivatives not designated as hedging instruments $ 2 $ 6
Netting Offsets of Derivative Assets	The following table presents net cash collateral offsetting arrangements for DTE Energy: March 31, 2019 December 31, 2018 (In millions) Cash collateral netted against Derivative assets $ (10 ) $ (17 ) Cash collateral recorded in Accounts receivable (a) 10 10 Cash collateral recorded in Accounts payable (a) (6 ) (6 ) Total net cash collateral posted (received) $ (6 ) $ (13 ) _______________________________________ (a) Amounts are recorded net by counterparty. The following table presents the netting offsets of Derivative assets and liabilities for DTE Energy: March 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 $ 178 $ (116 ) $ 62 $ 349 $ (277 ) $ 72 Electricity 155 (128 ) 27 303 (252 ) 51 Other 4 (2 ) 2 7 (1 ) 6 Foreign currency exchange contracts 3 — 3 4 — 4 Total derivative assets $ 340 $ (246 ) $ 94 $ 663 $ (530 ) $ 133 Derivative liabilities Commodity contracts Natural gas $ (166 ) $ 107 $ (59 ) $ (380 ) $ 272 $ (108 ) Electricity (165 ) 128 (37 ) (285 ) 240 (45 ) Other (1 ) 1 — (1 ) 1 — Interest rate contracts (6 ) — (6 ) (3 ) — (3 ) Total derivative liabilities $ (338 ) $ 236 $ (102 ) $ (669 ) $ 513 $ (156 )
Netting Offsets of Derivative Liabilities	The following table presents net cash collateral offsetting arrangements for DTE Energy: March 31, 2019 December 31, 2018 (In millions) Cash collateral netted against Derivative assets $ (10 ) $ (17 ) Cash collateral recorded in Accounts receivable (a) 10 10 Cash collateral recorded in Accounts payable (a) (6 ) (6 ) Total net cash collateral posted (received) $ (6 ) $ (13 ) _______________________________________ (a) Amounts are recorded net by counterparty. The following table presents the netting offsets of Derivative assets and liabilities for DTE Energy: March 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 $ 178 $ (116 ) $ 62 $ 349 $ (277 ) $ 72 Electricity 155 (128 ) 27 303 (252 ) 51 Other 4 (2 ) 2 7 (1 ) 6 Foreign currency exchange contracts 3 — 3 4 — 4 Total derivative assets $ 340 $ (246 ) $ 94 $ 663 $ (530 ) $ 133 Derivative liabilities Commodity contracts Natural gas $ (166 ) $ 107 $ (59 ) $ (380 ) $ 272 $ (108 ) Electricity (165 ) 128 (37 ) (285 ) 240 (45 ) Other (1 ) 1 — (1 ) 1 — Interest rate contracts (6 ) — (6 ) (3 ) — (3 ) Total derivative liabilities $ (338 ) $ 236 $ (102 ) $ (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: March 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 $ 266 $ 74 $ (237 ) $ (101 ) $ 563 $ 100 $ (518 ) $ (151 ) Counterparty netting (187 ) (49 ) 187 49 (451 ) (62 ) 451 62 Collateral adjustment (7 ) (3 ) — — (10 ) (7 ) — — Total derivatives as reported $ 72 $ 22 $ (50 ) $ (52 ) $ 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 the Three Months Ended March 31, 2019 2018 (In millions) Commodity contracts Natural gas Operating Revenues — Non-utility operations $ (15 ) $ (110 ) Natural gas Fuel, purchased power, and gas — non-utility 70 52 Electricity Operating Revenues — Non-utility operations (49 ) 129 Other Operating Revenues — Non-utility operations 1 (1 ) Foreign currency exchange contracts Operating Revenues — Non-utility operations (1 ) 2 Total $ 6 $ 72
Volume of Commodity Contracts	The following represents the cumulative gross volume of DTE Energy's derivative contracts outstanding as of March 31, 2019 : Commodity Number of Units Natural gas (MMBtu) 2,537,411,045 Electricity (MWh) 33,565,053 Foreign currency exchange (Canadian dollars) 97,013,854

Long-Term Debt (Tables)

Long-Term Debt (Tables)	3 Months Ended
	Mar. 31, 2019
Debt Disclosure [Abstract]
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 $ 650 _______________________________________ (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.

Short-Term Credit Arrangement_2

Short-Term Credit Arrangements and Borrowings (Tables)	3 Months Ended
	Mar. 31, 2019
Short-term Debt [Abstract]
Schedule of Line of Credit Facilities	The availability under the facilities in place at March 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 September 2019 70 — — 70 Unsecured revolving credit facility, expiring April 2022 1,200 400 300 1,900 1,420 400 300 2,120 Amounts outstanding at March 31, 2019 Commercial paper issuances 77 — 79 156 Letters of credit 195 — — 195 272 — 79 351 Net availability at March 31, 2019 $ 1,148 $ 400 $ 221 $ 1,769

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Components of Lease Cost and Other Information Related to Leases	The components of lease cost for DTE Energy were as follows: Three months ended March 31, 2019 (In millions) Operating lease cost $ 11 Finance lease cost: Amortization of right-of-use assets 1 Interest of lease liabilities — Total finance lease cost 1 Variable lease cost 5 $ 17 The components of lease cost for DTE Electric were as follows: Three months ended March 31, 2019 (In millions) Operating lease cost $ 4 Finance lease cost: Amortization of right-of-use assets 1 Interest of lease liabilities — Total finance lease cost 1 Variable lease cost — $ 5 Other information related to leases were as follows for the three months ended March 31, DTE Energy DTE Electric 2019 2019 (In millions) Supplemental Cash Flows Information Cash paid for amounts included in the measurement of these liabilities: Operating cash flows from finance leases $ 1 $ 1 Operating cash flows from operating leases $ 10 $ 3 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 11 $ — Weighted Average Remaining Lease Term Operating leases 9.1 years 10.4 years Finance leases 2.7 years 2.7 years Weighted Average Discount Rate Operating leases 3.8% 3.6% Finance leases 3.0% 3.0%
Schedule of Maturities of Operating Leases	The Registrants' future minimum lease payments under leases for remaining periods as of March 31, 2019 were as follows: DTE Energy DTE Electric Operating Leases Finance Leases Operating Leases Finance Leases (In millions) 2019 $ 28 $ 3 $ 12 $ 3 2020 30 4 12 4 2021 22 3 11 3 2022 16 — 7 — 2023 13 — 6 — 2024 and thereafter 50 — 30 — Total future minimum lease payments 159 10 78 10 Imputed interest (28 ) — (14 ) — $ 131 $ 10 $ 64 $ 10
Schedule of Maturities of Finance Leases	The Registrants' future minimum lease payments under leases for remaining periods as of March 31, 2019 were as follows: DTE Energy DTE Electric Operating Leases Finance Leases Operating Leases Finance Leases (In millions) 2019 $ 28 $ 3 $ 12 $ 3 2020 30 4 12 4 2021 22 3 11 3 2022 16 — 7 — 2023 13 — 6 — 2024 and thereafter 50 — 30 — Total future minimum lease payments 159 10 78 10 Imputed interest (28 ) — (14 ) — $ 131 $ 10 $ 64 $ 10
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 March 31, 2019 (In millions) Right-of-use assets, within Property, plant, and equipment, net $ 10 $ 10 Current lease liabilities, within Current Liabilities — Other $ 4 $ 4
Schedule of Future Minimum Lease Payments and Rental Revenues for Operating Leases	DTE Energy’s minimum future rental revenues under non-cancelable operating leases as of December 31, 2018 were: DTE Energy (In millions) 2019 $ 66 2020 66 2021 64 2022 20 2023 20 2024 and thereafter 196 $ 432 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
Schedule of Lease Income Associated with Operating Leases	DTE Energy’s lease income associated with operating leases were as follows: Three months ended March 31, 2019 (In millions) Fixed payments $ 17 Variable payments 27 $ 44
Schedule of Minimum Future Rental Revenues under Operating Leases	DTE Energy’s minimum future rental revenues under operating leases for remaining periods as of March 31, 2019 were: DTE Energy (In millions) 2019 $ 50 2020 67 2021 65 2022 22 2023 22 2024 and thereafter 216 $ 442
Schedule of Property under Operating Leases - Topic 842	Property under operating leases for DTE Energy were as follows: DTE Energy March 31, 2019 (In millions) Gross property under operating leases $ 442 Accumulated amortization of property under operating leases $ 154
Components of Net Investment in Finance Leases	The components of DTE Energy’s net investment in finance leases for remaining periods were as follows: DTE Energy March 31, 2019 (In millions) 2019 $ 7 2020 9 2021 — 2022 — 2023 — 2024 and thereafter 1 Total minimum future lease receipts 17 Residual value of leased pipeline 40 Less unearned income 8 Net investment in finance lease 49 Less current portion 5 $ 44
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

Retirement Benefits and Trust_2

Retirement Benefits and Trusteed Assets (Tables)	3 Months Ended
	Mar. 31, 2019
Defined Benefit Plan [Abstract]
Schedule of Net Periodic Benefit Costs (Credits)	The following tables detail the components of net periodic benefit costs (credits) for other postretirement benefits for DTE Electric: Other Postretirement Benefits Three Months Ended March 31, 2019 2018 (In millions) Service cost $ 4 $ 5 Interest cost 13 13 Expected return on plan assets (21 ) (24 ) Amortization of: Net actuarial loss 1 2 Prior service credit (1 ) — Net periodic benefit credit $ (4 ) $ (4 ) The following tables detail the components of net periodic benefit costs (credits) for pension benefits and other postretirement benefits for DTE Energy: Pension Benefits Other Postretirement Benefits Three Months Ended March 31, 2019 2018 2019 2018 (In millions) Service cost $ 21 $ 25 $ 5 $ 7 Interest cost 55 50 18 17 Expected return on plan assets (81 ) (82 ) (31 ) (36 ) Amortization of: Net actuarial loss 32 44 3 3 Prior service credit — — (2 ) — Net periodic benefit cost (credit) $ 27 $ 37 $ (7 ) $ (9 )
Schedule of Defined Benefit Plans Disclosures	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

Segment and Related Informati_2

Segment and Related Information (Tables)	3 Months Ended
	Mar. 31, 2019
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	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: Three Months Ended March 31, 2019 2018 (In millions) Electric $ 14 $ 13 Gas 2 2 Gas Storage and Pipelines 3 8 Power and Industrial Projects 145 155 Energy Trading 7 7 Corporate and Other 1 1 $ 172 $ 186 Financial data of DTE Energy's business segments follows: Three Months Ended March 31, 2019 2018 (In millions) Operating Revenues — Utility operations Electric $ 1,235 $ 1,205 Gas 645 550 Operating Revenues — Non-utility operations Gas Storage and Pipelines 116 119 Power and Industrial Projects 388 567 Energy Trading 1,301 1,498 Corporate and Other 1 — Reconciliation and Eliminations (172 ) (186 ) Total $ 3,514 $ 3,753 Three Months Ended March 31, 2019 2018 (In millions) Net Income (Loss) Attributable to DTE Energy by Segment: Electric $ 147 $ 140 Gas 151 104 Gas Storage and Pipelines 48 62 Power and Industrial Projects 26 45 Energy Trading 32 31 Corporate and Other (3 ) (21 ) Net Income Attributable to DTE Energy Company $ 401 $ 361

Organization and Basis of Pre_3

Organization and Basis of Presentation (Details Textuals) customer in Millions	Mar. 31, 2019USD ($)customer
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Number of electric utility customers | customer	2.2
Number of gas utility customers | customer	1.3
Significant potential exposure | $	$ 0
DTE Electric
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Significant 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]
Percent of assets acquired	55.00%

Organization and Basis of Pre_4

Organization and Basis of Presentation (Consolidated Variable Interest Entities) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
ASSETS
Cash and cash equivalents	$ 56	$ 71
Restricted cash	5	5
Accounts receivable	1,683	1,789
Property, plant, and equipment, net	21,864	21,650
Goodwill	2,293	2,293
Intangible assets	846	849
Total Assets	36,434	36,288
Variable interest entity, primary beneficiary, restricted
ASSETS
Cash and cash equivalents	35	39
Restricted cash	5	5
Accounts receivable	38	46
Inventories	47	93
Property, plant, and equipment, net	436	441
Goodwill	25	25
Intangible assets	553	557
Other current and long-term assets	1	3
Total Assets	1,140	1,209
LIABILITIES
Accounts payable and accrued current liabilities	23	34
Other current and long-term liabilities	18	19
Total liabilities	41	53
SGG
ASSETS
Cash and cash equivalents	21	25
Restricted cash	0	0
Accounts receivable	10	9
Inventories	0	1
Property, plant, and equipment, net	394	395
Goodwill	25	25
Intangible assets	553	557
Other current and long-term assets	1	3
Total Assets	1,004	1,015
LIABILITIES
Accounts payable and accrued current liabilities	1	3
Other current and long-term liabilities	8	9
Total liabilities	$ 9	12
VIE ownership and non-ownership percentage	100.00%
VIE ownership percentage	55.00%
Other
ASSETS
Cash and cash equivalents	$ 14	14
Restricted cash	5	5
Accounts receivable	28	37
Inventories	47	92
Property, plant, and equipment, net	42	46
Goodwill	0	0
Intangible assets	0	0
Other current and long-term assets	0	0
Total Assets	136	194
LIABILITIES
Accounts payable and accrued current liabilities	22	31
Other current and long-term liabilities	10	10
Total liabilities	$ 32	$ 41

Organization and Basis of Pre_5

Organization and Basis of Presentation (Non-Consolidated Variable Interest Entities) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Variable Interest Entity [Line Items]
Investments in equity method investees	$ 1,772	$ 1,771
Notes receivable	158	64
Variable interest entity, non-consolidated
Variable Interest Entity [Line Items]
Investments in equity method investees	1,412	1,425
Notes receivable	26	15
Future funding commitments	$ 64	$ 55

Significant Accounting Polici_4

Significant Accounting Policies Significant Accounting Policies (Other Income) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Schedule of Other Nonoperating Income, by Component [Line Items]
Income from REF entities	$ 27	$ 23
Equity earnings of equity method investees	23	21
Gains from equity securities	17	0
Contract services	8	20
Allowance for equity funds used during construction	7	7
Other	6	10
Total other income	88	81
DTE Electric
Schedule of Other Nonoperating Income, by Component [Line Items]
Gains from equity securities	17	0
Contract services	8	20
Allowance for equity funds used during construction	6	5
Other	2	2
Total other income	$ 33	$ 27

Significant Accounting Polici_5

Significant Accounting Policies (Details Textuals) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Significant Accounting Policies [Line Items]
Estimated annual effective tax rates	12.00%	16.00%
Effective tax rate increase (decrease)	(4.00%)
Amortization of TCJA regulatory liability	3.00%
Remeasurement of deferred taxes	$ 21
Measurement period impact to effective tax rate	5.00%
Annual production tax credits	5.00%
Unrecognized tax benefits	$ 8
Unrecognized compensation cost	$ 121
Recognition period (in years)	1 year 9 months 7 days
DTE Electric
Significant Accounting Policies [Line Items]
Estimated annual effective tax rates	16.00%	25.00%
Effective tax rate increase (decrease)	(9.00%)
Amortization of TCJA regulatory liability	4.00%
Remeasurement of deferred taxes	$ 8
Measurement period impact to effective tax rate	4.00%
Annual production tax credits	1.00%
Unrecognized tax benefits	$ 10
DTE Electric | DTE Energy
Significant Accounting Policies [Line Items]
Income tax receivable	3			$ 8
Allocated costs	$ 13	$ 9
Forecast
Significant Accounting Policies [Line Items]
Estimated annual effective tax rates			12.00%
Forecast | DTE Electric
Significant Accounting Policies [Line Items]
Estimated annual effective tax rates			16.00%

Significant Accounting Polici_6

Significant Accounting Policies (Income Taxes) (Details)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Schedule of Income Taxes [Line Items]
Effective Tax Rate	12.00%	16.00%
DTE Electric
Schedule of Income Taxes [Line Items]
Effective Tax Rate	16.00%	25.00%

Significant Accounting Polici_7

Significant Accounting Policies (Cash and Restricted Cash) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Cash and cash equivalents	$ 56	$ 71
Restricted cash	5	5
Total cash, cash equivalents, and restricted cash shown in the Consolidated Statements of Cash Flows	$ 61	$ 76	$ 186	$ 89

New Accounting Pronouncements (

New Accounting Pronouncements (Details) - USD ($) $ in Millions	Mar. 31, 2019	Jan. 01, 2019	Jan. 01, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right-of-use assets for certain operating leases	$ 138
Lease liabilities for certain operating leases	131
Reclassification of income tax effects		$ 0	$ 0
DTE Electric
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right-of-use assets for certain operating leases	70
Lease liabilities for certain operating leases	$ 64
Reclassification of income tax effects			0
Accumulated Other Comprehensive Income (Loss)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of income tax effects		(25)	(5)
Accumulated Other Comprehensive Income (Loss) | DTE Electric
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of income tax effects			(3)
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of income tax effects		25	5
Retained Earnings | DTE Electric
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of income tax effects			$ 3
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right-of-use assets for certain operating leases		137
Lease liabilities for certain operating leases		130
Prepaid lease costs reclassified from Other assets, current and noncurrent		9
Deferred lease costs reclassified from Other liabilities, current and noncurrent		2
Accounting Standards Update 2016-02 | DTE Electric
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right-of-use assets for certain operating leases		74
Lease liabilities for certain operating leases		67
Accounting Standards Update 2018-02 | Accumulated Other Comprehensive Income (Loss)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of income tax effects		(25)
Accounting Standards Update 2018-02 | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of income tax effects		$ 25

Revenue - Disaggregation of Rev

Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Revenues	$ 3,514	$ 3,753
Electric
Disaggregation of Revenue [Line Items]
Revenues	1,235	1,205
Reduction of revenue due to Tax Cuts and Jobs Act		39
Electric | Other
Disaggregation of Revenue [Line Items]
Revenues	4	5
Electric | Residential
Disaggregation of Revenue [Line Items]
Revenues	553	586
Electric | Commercial
Disaggregation of Revenue [Line Items]
Revenues	421	429
Electric | Industrial
Disaggregation of Revenue [Line Items]
Revenues	163	176
Electric | Other
Disaggregation of Revenue [Line Items]
Revenues	98	14
Gas
Disaggregation of Revenue [Line Items]
Revenues	645	550
Reduction of revenue due to Tax Cuts and Jobs Act		32
Gas | Alternative Revenue Programs
Disaggregation of Revenue [Line Items]
Revenues		3
Gas | Other
Disaggregation of Revenue [Line Items]
Revenues	2	2
Gas | Other
Disaggregation of Revenue [Line Items]
Revenues	61	(10)
Gas | Gas sales
Disaggregation of Revenue [Line Items]
Revenues	477	457
Gas | End User Transportation
Disaggregation of Revenue [Line Items]
Revenues	81	85
Gas | Intermediate Transportation
Disaggregation of Revenue [Line Items]
Revenues	26	18
Gas Storage and Pipelines
Disaggregation of Revenue [Line Items]
Revenues	116	119
Lease revenue outside scope of Topic 606	2
Power and Industrial Projects
Disaggregation of Revenue [Line Items]
Revenues	388	567
Lease revenue outside scope of Topic 606	31	28
Energy Trading
Disaggregation of Revenue [Line Items]
Revenues	1,301	1,498
Gain (loss) on derivative outside scope of Topic 606	$ 926	$ 1,200

Revenue - Deferred Revenue (Det

Revenue - Deferred Revenue (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Contract Liability [Roll Forward]
Beginning Balance	$ 74
Increases due to cash received or receivable, excluding amounts recognized as revenue during the period	17
Revenue recognized that was included in the deferred revenue balance at the beginning of the period	(16)
Ending Balance	$ 75

Revenue - Expected Recognition

Revenue - Expected Recognition of Deferred Revenue (Details) $ in Millions	Mar. 31, 2019USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
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
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]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 5
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	$ 11
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 Pe

Revenue - Expected Timing of Performance Obligation Satisfaction (Details) $ in Millions	Mar. 31, 2019USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
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
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]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 5
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	$ 11
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
Fixed-price Contract | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 173
Remaining performance obligation, expected timing of satisfaction	1 year
Fixed-price Contract | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01 | DTE Electric
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 6
Remaining performance obligation, expected timing of satisfaction	1 year
Fixed-price Contract | 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	$ 295
Remaining performance obligation, expected timing of satisfaction	1 year
Fixed-price Contract | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01 | DTE Electric
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 0
Remaining performance obligation, expected timing of satisfaction	1 year
Fixed-price Contract | 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	$ 240
Remaining performance obligation, expected timing of satisfaction	1 year
Fixed-price Contract | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01 | DTE Electric
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 0
Remaining performance obligation, expected timing of satisfaction	1 year
Fixed-price Contract | 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	$ 188
Remaining performance obligation, expected timing of satisfaction	1 year
Fixed-price Contract | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01 | DTE Electric
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 0
Remaining performance obligation, expected timing of satisfaction	1 year
Fixed-price Contract | 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	$ 134
Remaining performance obligation, expected timing of satisfaction	1 year
Fixed-price Contract | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01 | DTE Electric
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 0
Remaining performance obligation, expected timing of satisfaction	1 year
Fixed-price Contract | 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	$ 656
Remaining performance obligation, expected timing of satisfaction
Fixed-price Contract | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01 | DTE Electric
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 0
Remaining performance obligation, expected timing of satisfaction
Fixed-price Contract | 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	$ 1,686
Fixed-price Contract | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil) | DTE Electric
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 6

Revenue - Narrative (Details)

Revenue - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Revenue from External Customer [Line Items]
Allowance for doubtful accounts receivable write-offs	$ 29	$ 25
DTE Electric
Revenue from External Customer [Line Items]
Allowance for doubtful accounts receivable write-offs	$ 16	$ 14

Regulatory Matters (Details Tex

Regulatory Matters (Details Textuals) - USD ($) $ in Millions	Feb. 01, 2019	Dec. 06, 2018	Dec. 05, 2018	Nov. 16, 2018	Jul. 06, 2018	Jun. 28, 2018	Apr. 18, 2018	Nov. 01, 2017	Apr. 19, 2017	Mar. 31, 2019	Aug. 31, 2018
DTE Electric | MPSC | Electric Rate Case Filing 2017
Public Utilities, General Disclosures [Line Items]
Requested rate increase								$ 125	$ 231
Approved rate increase						$ 74.4	$ 65.2
Return on equity percent							10.00%
DTE Electric | MPSC | Electric Rate Case Filing 2017 | Refundable self-implemented rates
Public Utilities, General Disclosures [Line Items]
Amount filed to refund to customers											$ 26.2
Approved refund amount										$ 27.2
DTE Electric | MPSC | Electric Rate Case Filing 2018
Public Utilities, General Disclosures [Line Items]
Requested rate increase	$ 248.6				$ 328
Return on equity percent					10.00%
Return on equity requested percent					10.50%
DTE Electric | MPSC | 2016 DTE Electric Depreciation Case Filing
Public Utilities, General Disclosures [Line Items]
Approved composite depreciation rate increase		3.72%	3.06%
DTE Gas
Public Utilities, General Disclosures [Line Items]
Calculation C, reduction of revenue due to Tax Cuts and Jobs Act, requested				$ 12

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Basic Earnings per Share
Net Income Attributable to DTE Energy Company	$ 401	$ 361
Less: Allocation of earnings to net restricted stock awards	1	1
Net income available to common shareholders — basic	$ 400	$ 360
Average number of common shares outstanding — basic (in shares)	182	180
Basic Earnings per Common Share (in dollars per share)	$ 2.20	$ 2.01
Diluted Earnings per Share
Net Income Attributable to DTE Energy Company	$ 401	$ 361
Less: Allocation of earnings to net restricted stock awards	1	1
Net income available to common shareholders — diluted	$ 400	$ 360
Average number of common shares outstanding — basic (in shares)	182	180
Incremental shares attributable to:
Average dilutive equity units, performance share awards, and stock options (in shares)	1	0
Average number of common shares outstanding — diluted (in shares)	183	180
Diluted Earnings per Common Share (in dollars per share)	$ 2.19	$ 2
Antidilutive securities excluded from computation of earnings per share (in shares)		6.6

Fair Value (Assets and Liabilit

Fair Value (Assets and Liabilities Recorded at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Derivative assets
Derivative assets, gross	$ 340	$ 663
Derivative asset, netting	(246)	(530)
Derivative assets, net	94	133
Derivative liabilities
Derivative liabilities, gross	(338)	(669)
Derivative liability, netting	236	513
Derivative liabilities, net	(102)	(156)
Current liabilities
Derivative liabilities
Derivative liabilities, gross	(237)	(518)
Noncurrent liabilities
Derivative liabilities
Derivative liabilities, gross	(101)	(151)
Natural gas
Derivative assets
Derivative assets, gross	178	349
Derivative asset, netting	(116)	(277)
Derivative assets, net	62	72
Derivative liabilities
Derivative liabilities, gross	(166)	(380)
Derivative liability, netting	107	272
Derivative liabilities, net	(59)	(108)
Electricity
Derivative assets
Derivative assets, gross	155	303
Derivative asset, netting	(128)	(252)
Derivative assets, net	27	51
Derivative liabilities
Derivative liabilities, gross	(165)	(285)
Derivative liability, netting	128	240
Derivative liabilities, net	(37)	(45)
Other
Derivative assets
Derivative assets, gross	4	7
Derivative asset, netting	(2)	(1)
Derivative assets, net	2	6
Derivative liabilities
Derivative liabilities, gross	(1)	(1)
Derivative liability, netting	1	1
Derivative liabilities, net	0	0
Interest rate contracts
Derivative liabilities
Derivative liabilities, gross	(6)	(3)
Derivative liability, netting	0	0
Derivative liabilities, net	(6)	(3)
Foreign currency exchange contracts
Derivative assets
Derivative assets, gross	3	4
Derivative asset, netting	0	0
Derivative assets, net	3	4
Recurring
Assets
Cash equivalents	19	18
Derivative assets
Derivative asset, netting	(246)	(530)
Derivative assets, net	94	133
Total assets	1,822	1,712
Derivative liabilities
Derivative liability, netting	236	513
Derivative liabilities, net	(102)	(156)
Net Assets (Liabilities) at end of period	1,720	1,556
Net Assets (Liabilities) at end of period, netting	(10)	(17)
Recurring | DTE Electric
Assets
Cash equivalents	10	10
Derivative assets
Total assets	1,532	1,404
Recurring | Current assets
Derivative assets
Derivative asset, netting	(194)	(461)
Total assets	91	120
Recurring | Current assets | DTE Electric
Derivative assets
Total assets	12	16
Recurring | Noncurrent assets
Derivative assets
Derivative asset, netting	(52)	(69)
Total assets	1,731	1,592
Recurring | Noncurrent assets | DTE Electric
Derivative assets
Total assets	1,520	1,388
Recurring | Current liabilities
Derivative liabilities
Derivative liability, netting	187	451
Derivative liabilities, net	(50)	(67)
Recurring | Noncurrent liabilities
Derivative liabilities
Derivative liability, netting	49	62
Derivative liabilities, net	(52)	(89)
Recurring | Cash and cash equivalents
Assets
Cash equivalents	4	3
Recurring | Restricted cash
Assets
Cash equivalents	5	5
Recurring | Other
Assets
Cash equivalents	10	10
Recurring | Other | DTE Electric
Assets
Cash equivalents	10	10
Recurring | Natural gas
Derivative assets
Derivative asset, netting	(116)	(277)
Derivative assets, net	62	72
Derivative liabilities
Derivative liability, netting	107	272
Derivative liabilities, net	(59)	(108)
Recurring | Electricity
Derivative assets
Derivative asset, netting	(128)	(252)
Derivative assets, net	27	51
Derivative liabilities
Derivative liability, netting	128	240
Derivative liabilities, net	(37)	(45)
Recurring | Other
Derivative assets
Derivative asset, netting	(2)	(1)
Derivative assets, net	2	6
Derivative liabilities
Derivative liability, netting	1	1
Derivative liabilities, net	0	0
Recurring | Interest rate contracts
Derivative liabilities
Derivative liability, netting	0	0
Derivative liabilities, net	(6)	(3)
Recurring | Foreign currency exchange contracts
Derivative assets
Derivative asset, netting	0	0
Derivative assets, net	3	4
Derivative liabilities
Derivative liability, netting	0	0
Derivative liabilities, net	0	0
Recurring | Derivative assets — FTRs | DTE Electric
Derivative assets
Derivative assets, net	2	6
Recurring | Cash equivalents
Assets
Nuclear decommissioning trusts	5	5
Other investments	4	4
Recurring | Cash equivalents | DTE Electric
Assets
Nuclear decommissioning trusts	5	5
Recurring | Private equity and other
Assets
Nuclear decommissioning trusts	23	20
Recurring | Private equity and other | DTE Electric
Assets
Nuclear decommissioning trusts	23	20
Recurring | Other
Assets
Other investments	0	0
Recurring | Equity securities
Assets
Nuclear decommissioning trusts	964	851
Other investments	124	110
Recurring | Equity securities | DTE Electric
Assets
Nuclear decommissioning trusts	964	851
Other investments	11	10
Recurring | Fixed income securities
Assets
Nuclear decommissioning trusts	517	502
Other investments	72	69
Recurring | Fixed income securities | DTE Electric
Assets
Nuclear decommissioning trusts	517	502
Recurring | Level 1
Assets
Cash equivalents	17	16
Derivative assets
Derivative assets, gross	43	199
Total assets	1,242	1,266
Derivative liabilities
Derivative liabilities, gross	(42)	(197)
Net Assets (Liabilities) at end of period	1,200	1,069
Recurring | Level 1 | DTE Electric
Assets
Cash equivalents	8	8
Derivative assets
Total assets	1,001	886
Recurring | Level 1 | Current assets
Derivative assets
Total assets	57	212
Recurring | Level 1 | Current assets | DTE Electric
Derivative assets
Total assets	8	8
Recurring | Level 1 | Noncurrent assets
Derivative assets
Total assets	1,185	1,054
Recurring | Level 1 | Noncurrent assets | DTE Electric
Derivative assets
Total assets	993	878
Recurring | Level 1 | Current liabilities
Derivative liabilities
Derivative liabilities, gross	(37)	(191)
Recurring | Level 1 | Noncurrent liabilities
Derivative liabilities
Derivative liabilities, gross	(5)	(6)
Recurring | Level 1 | Natural gas
Derivative assets
Derivative assets, gross	41	199
Derivative liabilities
Derivative liabilities, gross	(42)	(197)
Recurring | Level 1 | Electricity
Derivative assets
Derivative assets, gross	0	0
Derivative liabilities
Derivative liabilities, gross	0	0
Recurring | Level 1 | Other
Derivative assets
Derivative assets, gross	2	0
Derivative liabilities
Derivative liabilities, gross	0	0
Recurring | Level 1 | Interest rate contracts
Derivative liabilities
Derivative liabilities, gross	0	0
Recurring | Level 1 | Foreign currency exchange contracts
Derivative assets
Derivative assets, gross	0	0
Derivative liabilities
Derivative liabilities, 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	5	5
Other investments	4	4
Recurring | Level 1 | Cash equivalents | DTE Electric
Assets
Nuclear decommissioning trusts	5	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 | Other
Assets
Other investments	0	0
Recurring | Level 1 | Equity securities
Assets
Nuclear decommissioning trusts	964	851
Other investments	124	110
Recurring | Level 1 | Equity securities | DTE Electric
Assets
Nuclear decommissioning trusts	964	851
Other investments	11	10
Recurring | Level 1 | Fixed income securities
Assets
Nuclear decommissioning trusts	13	12
Other investments	72	69
Recurring | Level 1 | Fixed income securities | DTE Electric
Assets
Nuclear decommissioning trusts	13	12
Recurring | Level 2
Assets
Cash equivalents	2	2
Derivative assets
Derivative assets, gross	217	338
Total assets	723	830
Derivative liabilities
Derivative liabilities, gross	(183)	(302)
Net Assets (Liabilities) at end of period	540	528
Recurring | Level 2 | DTE Electric
Assets
Cash equivalents	2	2
Derivative assets
Total assets	506	492
Recurring | Level 2 | Current assets
Derivative assets
Total assets	167	273
Recurring | Level 2 | Current assets | DTE Electric
Derivative assets
Total assets	2	2
Recurring | Level 2 | Noncurrent assets
Derivative assets
Total assets	556	557
Recurring | Level 2 | Noncurrent assets | DTE Electric
Derivative assets
Total assets	504	490
Recurring | Level 2 | Current liabilities
Derivative liabilities
Derivative liabilities, gross	(147)	(251)
Recurring | Level 2 | Noncurrent liabilities
Derivative liabilities
Derivative liabilities, gross	(36)	(51)
Recurring | Level 2 | Natural gas
Derivative assets
Derivative assets, gross	80	87
Derivative liabilities
Derivative liabilities, gross	(57)	(71)
Recurring | Level 2 | Electricity
Derivative assets
Derivative assets, gross	134	247
Derivative liabilities
Derivative liabilities, gross	(119)	(227)
Recurring | Level 2 | Other
Derivative assets
Derivative assets, gross	0	0
Derivative liabilities
Derivative liabilities, gross	(1)	(1)
Recurring | Level 2 | Interest rate contracts
Derivative liabilities
Derivative liabilities, gross	(6)	(3)
Recurring | Level 2 | Foreign currency exchange contracts
Derivative assets
Derivative assets, gross	3	4
Derivative liabilities
Derivative liabilities, gross	0	0
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 | Other
Assets
Other investments	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	504	490
Other investments	0	0
Recurring | Level 2 | Fixed income securities | DTE Electric
Assets
Nuclear decommissioning trusts	504	490
Recurring | Level 3
Assets
Cash equivalents	0	0
Derivative assets
Derivative assets, gross	80	126
Total assets	80	126
Derivative liabilities
Derivative liabilities, gross	(113)	(170)
Net Assets (Liabilities) at end of period	(33)	(44)
Recurring | Level 3 | DTE Electric
Assets
Cash equivalents	0	0
Derivative assets
Total assets	2	6
Recurring | Level 3 | Current assets
Derivative assets
Total assets	61	96
Recurring | Level 3 | Current assets | DTE Electric
Derivative assets
Total assets	2	6
Recurring | Level 3 | Noncurrent assets
Derivative assets
Total assets	19	30
Recurring | Level 3 | Noncurrent assets | DTE Electric
Derivative assets
Total assets	0	0
Recurring | Level 3 | Current liabilities
Derivative liabilities
Derivative liabilities, gross	(53)	(76)
Recurring | Level 3 | Noncurrent liabilities
Derivative liabilities
Derivative liabilities, gross	(60)	(94)
Recurring | Level 3 | Natural gas
Derivative assets
Derivative assets, gross	57	63
Derivative liabilities
Derivative liabilities, gross	(67)	(112)
Recurring | Level 3 | Electricity
Derivative assets
Derivative assets, gross	21	56
Derivative liabilities
Derivative liabilities, gross	(46)	(58)
Recurring | Level 3 | Other
Derivative assets
Derivative assets, gross	2	7
Derivative liabilities
Derivative liabilities, gross	0	0
Recurring | Level 3 | Interest rate contracts
Derivative liabilities
Derivative liabilities, gross	0	0
Recurring | Level 3 | Foreign currency exchange contracts
Derivative assets
Derivative assets, gross	0	0
Derivative liabilities
Derivative liabilities, gross	0	0
Recurring | Level 3 | Derivative assets — FTRs | DTE Electric
Derivative assets
Derivative assets, net	2	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 | Other
Assets
Other investments	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	23	20
Derivative liabilities
Net Assets (Liabilities) at end of period	23	20
Recurring | Other | DTE Electric
Derivative assets
Total assets	23	20
Recurring | Other | Noncurrent assets
Derivative assets
Total assets	23	20
Recurring | Other | Noncurrent assets | DTE Electric
Derivative assets
Total assets	23	20
Recurring | Other | Private equity and other
Assets
Nuclear decommissioning trusts	23	20
Recurring | Other | Private equity and other | DTE Electric
Assets
Nuclear decommissioning trusts	$ 23	$ 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	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of beginning of period	$ (44)	$ (9)
Transfers into Level 3 from Level 2	0	0
Transfers from Level 3 into Level 2	0	(3)
Total gains (losses):
Included in earnings	(1)	61
Recorded in/Change in fair value recorded in Regulatory liabilities	(3)	0
Purchases, issuances, and settlements
Settlements	15	(68)
Net Assets (Liabilities) as of end of period	(33)	(19)
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 March 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	(6)	(68)
DTE Electric
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of beginning of period	6	9
Total gains (losses):
Recorded in/Change in fair value recorded in Regulatory liabilities	(3)	0
Purchases, issuances, and settlements
Settlements	(1)	(4)
Net Assets (Liabilities) as of end of period	2	5
The amount of total gains (losses) included in Regulatory liabilities attributed to the change in unrealized gains (losses) related to assets held at March 31, 2019 and 2018 and reflected in DTE Electric's Consolidated Statements of Financial Position	0	3
Natural gas
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of beginning of period	(49)	(29)
Transfers into Level 3 from Level 2	0	0
Transfers from Level 3 into Level 2	0	(3)
Total gains (losses):
Included in earnings	31	(70)
Recorded in/Change in fair value recorded in Regulatory liabilities	0	0
Purchases, issuances, and settlements
Settlements	8	92
Net Assets (Liabilities) as of end of period	(10)	(10)
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 March 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	16	(58)
Electricity
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of beginning of period	(2)	12
Transfers into Level 3 from Level 2	0	0
Transfers from Level 3 into Level 2	0	0
Total gains (losses):
Included in earnings	(31)	131
Recorded in/Change in fair value recorded in Regulatory liabilities	0	0
Purchases, issuances, and settlements
Settlements	8	(156)
Net Assets (Liabilities) as of end of period	(25)	(13)
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 March 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	(21)	(10)
Other
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of beginning of period	7	8
Transfers into Level 3 from Level 2	0	0
Transfers from Level 3 into Level 2	0	0
Total gains (losses):
Included in earnings	(1)	0
Recorded in/Change in fair value recorded in Regulatory liabilities	(3)	0
Purchases, issuances, and settlements
Settlements	(1)	(4)
Net Assets (Liabilities) as of end of period	2	4
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 March 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)	$ 0

Fair Value (Unobservable Inputs

Fair Value (Unobservable Inputs related to Level 3 Assets and Liabilities) (Details) $ in Millions	Mar. 31, 2019USD ($)$ / MMBTU$ / MWh	Dec. 31, 2018USD ($)$ / MMBTU$ / MWh
Unobservable Inputs Valuation Techniques [Line Items]
Derivative Assets	$ 340	$ 663
Derivative Liabilities	(338)	(669)
Recurring | Level 3
Unobservable Inputs Valuation Techniques [Line Items]
Derivative Assets	80	126
Derivative Liabilities	(113)	(170)
Natural gas
Unobservable Inputs Valuation Techniques [Line Items]
Derivative Assets	178	349
Derivative Liabilities	(166)	(380)
Natural gas | Recurring | Level 3
Unobservable Inputs Valuation Techniques [Line Items]
Derivative Assets	57	63
Derivative Liabilities	(67)	(112)
Electricity
Unobservable Inputs Valuation Techniques [Line Items]
Derivative Assets	155	303
Derivative Liabilities	(165)	(285)
Electricity | Recurring | Level 3
Unobservable Inputs Valuation Techniques [Line Items]
Derivative Assets	21	56
Derivative Liabilities	$ (46)	$ (58)
Forward basis price | Natural gas | Minimum | Discounted Cash Flow | Level 3
Unobservable Inputs Valuation Techniques [Line Items]
Forward basis price | $ / MMBTU	(0.88)	(2.15)
Forward basis price | Natural gas | Maximum | Discounted Cash Flow | Level 3
Unobservable Inputs Valuation Techniques [Line Items]
Forward basis price | $ / MMBTU	5.97	5.59
Forward basis price | Natural gas | Weighted Average | Discounted Cash Flow | Level 3
Unobservable Inputs Valuation Techniques [Line Items]
Forward basis price | $ / MMBTU	(0.07)	(0.10)
Forward basis price | Electricity | Minimum | Discounted Cash Flow | Level 3
Unobservable Inputs Valuation Techniques [Line Items]
Forward basis price | $ / MWh	(7)	(7)
Forward basis price | Electricity | Maximum | Discounted Cash Flow | Level 3
Unobservable Inputs Valuation Techniques [Line Items]
Forward basis price | $ / MWh	7	9
Forward basis price | Electricity | Weighted Average | Discounted Cash Flow | Level 3
Unobservable Inputs Valuation Techniques [Line Items]
Forward basis price | $ / MWh	0	1

Fair Value (Fair Value of Finan

Fair Value (Fair Value of Financial Instruments) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Carrying amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, excluding lessor finance leases	$ 143	$ 40
Dividends payable	173	172
Short-term borrowings	156	609
Notes payable — Other, excluding lessee finance leases	30	41
Long-term debt	14,265	13,622
Carrying amount | DTE Electric
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, excluding lessor finance leases	18	6
Short-term borrowings	0	149
Notes payable — Other, excluding lessee finance leases	23	21
Long-term debt	7,178	6,538
Carrying amount | DTE Electric | Affiliates
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, excluding lessor finance leases	83	0
Short-term borrowings	51	101
Fair value | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, excluding lessor finance leases	0	0
Dividends payable	173	172
Short-term borrowings	0	0
Notes payable — Other, excluding lessee finance leases	0	0
Long-term debt	1,960	1,796
Fair value | Level 1 | DTE Electric
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, 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 | Affiliates
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, excluding lessor finance leases	0	0
Short-term borrowings	0	0
Fair value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, excluding lessor finance leases	0	0
Dividends payable	0	0
Short-term borrowings	156	609
Notes payable — Other, excluding lessee finance leases	0	0
Long-term debt	11,615	10,712
Fair value | Level 2 | DTE Electric
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, excluding lessor finance leases	0	0
Short-term borrowings	0	149
Notes payable — Other, excluding lessee finance leases	0	0
Long-term debt	7,124	6,552
Fair value | Level 2 | DTE Electric | Affiliates
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, excluding lessor finance leases	0	0
Short-term borrowings	0	0
Fair value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, excluding lessor finance leases	143	40
Dividends payable	0	0
Short-term borrowings	0	0
Notes payable — Other, excluding lessee finance leases	30	41
Long-term debt	1,431	1,317
Fair value | Level 3 | DTE Electric
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, excluding lessor finance leases	18	6
Short-term borrowings	0	0
Notes payable — Other, excluding lessee finance leases	23	21
Long-term debt	491	161
Fair value | Level 3 | DTE Electric | Affiliates
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, excluding lessor finance leases	83	0
Short-term borrowings	$ 51	$ 101

Fair Value (Fair Value of Nucle

Fair Value (Fair Value of Nuclear Decommissioning Trust Fund Assets) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Nuclear decommissioning trust funds	$ 1,509	$ 1,378
DTE Electric
Debt Securities, Available-for-sale [Line Items]
Nuclear decommissioning trust funds	1,509	1,378
DTE Electric | Nuclear decommissioning trust fund
Debt Securities, Available-for-sale [Line Items]
Nuclear decommissioning trust funds	1,509	1,378
DTE Electric | Nuclear decommissioning trust fund | Fermi 2
Debt Securities, Available-for-sale [Line Items]
Nuclear decommissioning trust funds	1,502	1,372
DTE Electric | Nuclear decommissioning trust fund | Fermi 1
Debt Securities, Available-for-sale [Line Items]
Nuclear decommissioning trust funds	3	3
DTE Electric | Nuclear decommissioning trust fund | Low-level radioactive waste
Debt Securities, Available-for-sale [Line Items]
Nuclear decommissioning trust funds	$ 4	$ 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 trust fund - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Realized gains	$ 11	$ 23
Realized losses	(7)	(9)
Proceeds from sale of securities	$ 176	$ 336

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 trust fund - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Fair Value	$ 1,509	$ 1,378
Fixed income securities, fair value	517	502
Private equity and other, fair value	23	20
Cash equivalents, fair value	5	5
Unrealized Gains	326	242
Fixed income securities, unrealized gains	13	7
Unrealized Losses	(54)	(87)
Fixed income securities, unrealized losses	(3)	(8)
Equity securities
Debt Securities, Available-for-sale [Line Items]
Fair Value	964	851
Unrealized Gains	313	235
Unrealized Losses	$ (51)	$ (79)

Fair Value Fair Value (Fair Val

Fair Value Fair Value (Fair Value of Fixed Income Securities Held in Nuclear Decommissioning Trust Funds (Details) - Fixed income securities - Nuclear decommissioning trust fund $ in Millions	Mar. 31, 2019USD ($)
Debt Securities, Available-for-sale [Line Items]
Due within one year	$ 26
Due after one through five years	96
Due after five through ten years	109
Due after ten years	286
Available-for-sale securities total	$ 517

Fair Value (Details Textuals)

Fair Value (Details Textuals) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Equity securities realized gains	$ 17
Equity securities realized losses		$ 3

Financial and Other Derivativ_3

Financial and Other Derivative Instruments (Fair Value of Derivative Instruments) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 340	$ 663
Derivative Liabilities	(338)	(669)
Current derivative assets
Derivatives, Fair Value [Line Items]
Derivative Assets	266	563
Current derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(237)	(518)
Noncurrent derivative assets
Derivatives, Fair Value [Line Items]
Derivative Assets	74	100
Noncurrent derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(101)	(151)
Interest rate contracts
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(6)	(3)
Natural gas
Derivatives, Fair Value [Line Items]
Derivative Assets	178	349
Derivative Liabilities	(166)	(380)
Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	155	303
Derivative Liabilities	(165)	(285)
Other
Derivatives, Fair Value [Line Items]
Derivative Assets	4	7
Derivative Liabilities	(1)	(1)
Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	3	4
Derivatives designated as hedging instruments | Interest rate contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	0	0
Derivative Liabilities	(6)	(3)
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets	340	663
Derivative Liabilities	(332)	(666)
Derivatives not designated as hedging instruments | DTE Electric
Derivatives, Fair Value [Line Items]
Derivative Assets	2	6
Derivatives not designated as hedging instruments | Natural gas
Derivatives, Fair Value [Line Items]
Derivative Assets	178	349
Derivative Liabilities	(166)	(380)
Derivatives not designated as hedging instruments | Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	155	303
Derivative Liabilities	(165)	(285)
Derivatives not designated as hedging instruments | Other
Derivatives, Fair Value [Line Items]
Derivative Assets	4	7
Derivative Liabilities	(1)	(1)
Derivatives not designated as hedging instruments | Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	3	4
Derivative Liabilities	0	0
Derivatives not designated as hedging instruments | FTRs — Other current assets | DTE Electric
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 2	$ 6

Financial and Other Derivativ_4

Financial and Other Derivative Instruments (Details Textuals) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Letters of credit that could be used to offset net derivative liabilities	$ 4	$ 4
Letters of credit received that could be used to offset net derivative assets	8	$ 8
Contractual obligation to post collateral in event of downgrade to below investment grade	537
Derivative net liability position aggregate fair value	263
Collateral already posted fair value	1
Derivative net asset position, fair value	222
Remaining amount of offsets to derivative net liability positions for hard and soft trigger provisions	$ 40

Financial and Other Derivativ_5

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

Financial and Other Derivativ_6

Financial and Other Derivative Instruments (Netting Offsets of Derivative Assets and Liabilities) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Derivative assets
Gross Amounts of Recognized Assets (Liabilities)	$ 340	$ 663
Gross Amounts Offset in the Consolidated Statements of Financial Position	(246)	(530)
Derivative assets, net	94	133
Derivative liabilities
Gross Amounts of Recognized Assets (Liabilities)	(338)	(669)
Gross Amounts Offset in the Consolidated Statements of Financial Position	236	513
Derivative liabilities, net	(102)	(156)
Natural gas
Derivative assets
Gross Amounts of Recognized Assets (Liabilities)	178	349
Gross Amounts Offset in the Consolidated Statements of Financial Position	(116)	(277)
Derivative assets, net	62	72
Derivative liabilities
Gross Amounts of Recognized Assets (Liabilities)	(166)	(380)
Gross Amounts Offset in the Consolidated Statements of Financial Position	107	272
Derivative liabilities, net	(59)	(108)
Electricity
Derivative assets
Gross Amounts of Recognized Assets (Liabilities)	155	303
Gross Amounts Offset in the Consolidated Statements of Financial Position	(128)	(252)
Derivative assets, net	27	51
Derivative liabilities
Gross Amounts of Recognized Assets (Liabilities)	(165)	(285)
Gross Amounts Offset in the Consolidated Statements of Financial Position	128	240
Derivative liabilities, net	(37)	(45)
Other
Derivative assets
Gross Amounts of Recognized Assets (Liabilities)	4	7
Gross Amounts Offset in the Consolidated Statements of Financial Position	(2)	(1)
Derivative assets, net	2	6
Derivative liabilities
Gross Amounts of Recognized Assets (Liabilities)	(1)	(1)
Gross Amounts Offset in the Consolidated Statements of Financial Position	1	1
Derivative liabilities, net	0	0
Interest rate contracts
Derivative liabilities
Gross Amounts of Recognized Assets (Liabilities)	(6)	(3)
Gross Amounts Offset in the Consolidated Statements of Financial Position	0	0
Derivative liabilities, net	(6)	(3)
Foreign currency exchange contracts
Derivative assets
Gross Amounts of Recognized Assets (Liabilities)	3	4
Gross Amounts Offset in the Consolidated Statements of Financial Position	0	0
Derivative assets, net	$ 3	$ 4

Financial and Other Derivativ_7

Financial and Other Derivative Instruments (Netting Offsets Reconciliation to Balance Sheet) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Derivative Assets
Derivative Assets	$ 340	$ 663
Collateral adjustment	(10)	(17)
Derivative assets, current	72	102
Derivative assets, noncurrent	22	31
Derivative Liabilities
Derivative Liabilities	(338)	(669)
Derivative liabilities, current	(50)	(67)
Derivative liabilities, noncurrent	(52)	(89)
Current derivative assets
Derivative Assets
Derivative Assets	266	563
Counterparty netting	(187)	(451)
Collateral adjustment	(7)	(10)
Derivative assets, current	72	102
Noncurrent derivative assets
Derivative Assets
Derivative Assets	74	100
Counterparty netting	(49)	(62)
Collateral adjustment	(3)	(7)
Derivative assets, noncurrent	22	31
Current derivative liabilities
Derivative Liabilities
Derivative Liabilities	(237)	(518)
Counterparty netting	187	451
Collateral adjustment	0	0
Derivative liabilities, current	(50)	(67)
Noncurrent derivative liabilities
Derivative Liabilities
Derivative Liabilities	(101)	(151)
Counterparty netting	49	62
Collateral adjustment	0	0
Derivative liabilities, noncurrent	$ (52)	$ (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	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivatives	$ 6	$ 72
Natural gas | Operating Revenues — Non-utility operations
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivatives	(15)	(110)
Natural gas | Fuel, purchased power, and gas — non-utility
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivatives	70	52
Electricity | Operating Revenues — Non-utility operations
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivatives	(49)	129
Other | Operating Revenues — Non-utility operations
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivatives	1	(1)
Foreign currency exchange contracts | Operating Revenues — Non-utility operations
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivatives	$ (1)	$ 2

Financial and Other Derivativ_9

Financial and Other Derivative Instruments (Cumulative Gross Volume of Derivative Contracts Outstanding) (Details)	3 Months Ended
	Mar. 31, 2019CAD ($)MMBTUMWh
Natural gas (MMBtu)
Derivative [Line Items]
Commodity | MMBTU	2,537,411,045
Electricity (MWh)
Derivative [Line Items]
Commodity | MWh	33,565,053
Foreign currency exchange (Canadian dollars)
Derivative [Line Items]
Foreign currency exchange (Canadian dollars) | $	$ 97,013,854

Long-Term Debt (Details)

Long-Term Debt (Details)	Mar. 31, 2019USD ($)
Debt Instrument [Line Items]
Debt issued	$ 650,000,000
DTE Electric | Mortgage Bonds | May 2018 4.05% Mortgage Bonds Maturing 2048
Debt Instrument [Line Items]
Interest rate	3.95%
Debt issued	$ 650,000,000

Short-Term Credit Arrangement_3

Short-Term Credit Arrangements and Borrowings (Details Textuals)	1 Months Ended
	Apr. 24, 2019USD ($)	Mar. 31, 2019USD ($)	Feb. 28, 2019USD ($)	Dec. 31, 2018USD ($)
Short-term Debt [Line Items]
Maximum borrowing capacity		$ 2,120,000,000
Other outstanding letters of credit		351,000,000
Letter of credit
Short-term Debt [Line Items]
Other outstanding letters of credit		195,000,000
Unsecured letter of credit facility, expiring in February 2021 | Letter of credit
Short-term Debt [Line Items]
Maximum borrowing capacity		150,000,000
Unsecured revolving credit facility, expiring April 2022 | Revolving credit facility
Short-term Debt [Line Items]
Maximum borrowing capacity		$ 1,900,000,000
Unsecured revolving credit facility, expiring April 2024 | Revolving credit facility | Subsequent event
Short-term Debt [Line Items]
Term of credit agreement	5 years
DTE Electric
Short-term Debt [Line Items]
Ratio of indebtedness to net capital		0.51
Maximum borrowing capacity		$ 400,000,000
Other outstanding letters of credit		0
DTE Electric | Letter of credit
Short-term Debt [Line Items]
Other outstanding letters of credit		0
DTE Electric | Unsecured letter of credit facility, expiring in February 2021 | Letter of credit
Short-term Debt [Line Items]
Maximum borrowing capacity		0
DTE Electric | Unsecured revolving credit facility, expiring April 2022 | Revolving credit facility
Short-term Debt [Line Items]
Maximum borrowing capacity		$ 400,000,000
DTE Electric | Unsecured revolving credit facility, expiring April 2024 | Revolving credit facility | Subsequent event
Short-term Debt [Line Items]
Maximum borrowing capacity	$ 500,000,000
DTE Gas
Short-term Debt [Line Items]
Ratio of indebtedness to net capital		0.46
Maximum borrowing capacity		$ 300,000,000
Other outstanding letters of credit		79,000,000
DTE Gas | Letter of credit
Short-term Debt [Line Items]
Other outstanding letters of credit		0
DTE Gas | Unsecured letter of credit facility, expiring in February 2021 | Letter of credit
Short-term Debt [Line Items]
Maximum borrowing capacity		0
DTE Gas | Unsecured revolving credit facility, expiring April 2022 | Revolving credit facility
Short-term Debt [Line Items]
Maximum borrowing capacity		$ 300,000,000
DTE Energy
Short-term Debt [Line Items]
Ratio of indebtedness to net capital		0.55
Maximum borrowing capacity		$ 1,420,000,000
Other outstanding letters of credit		272,000,000
DTE Energy | Letter of credit
Short-term Debt [Line Items]
Other outstanding letters of credit		195,000,000
DTE Energy | Demand financing agreement
Short-term Debt [Line Items]
Maximum borrowing capacity, financing agreement		100,000,000
Maximum additional margin financing		50,000,000
Amount outstanding		79,000,000		$ 93,000,000
DTE Energy | Demand financing agreement plus letter of credit
Short-term Debt [Line Items]
Maximum borrowing capacity, financing agreement		150,000,000
DTE Energy | Unsecured letter of credit facility, expiring in February 2021 | Letter of credit
Short-term Debt [Line Items]
Maximum borrowing capacity		150,000,000	$ 150,000,000
DTE Energy | Unsecured revolving credit facility, expiring April 2022 | Revolving credit facility
Short-term Debt [Line Items]
Maximum borrowing capacity		1,200,000,000
DTE Energy | Unsecured revolving credit facility, expiring April 2024 | Revolving credit facility | Subsequent event
Short-term Debt [Line Items]
Maximum borrowing capacity	$ 1,500,000,000
DTE Energy | Other outstanding letters of credit | Letter of credit
Short-term Debt [Line Items]
Other outstanding letters of credit		$ 9,000,000
Maximum
Short-term Debt [Line Items]
Ratio of indebtedness to net capital		0.65

Short-Term Credit Arrangement_4

Short-Term Credit Arrangements and Borrowings (Details) - USD ($)	Mar. 31, 2019	Feb. 28, 2019
Availability under combined facilities
Maximum borrowing capacity	$ 2,120,000,000
Amounts outstanding	351,000,000
Net availability	1,769,000,000
DTE Electric
Availability under combined facilities
Maximum borrowing capacity	400,000,000
Amounts outstanding	0
Net availability	400,000,000
DTE Gas
Availability under combined facilities
Maximum borrowing capacity	300,000,000
Amounts outstanding	79,000,000
Net availability	221,000,000
DTE Energy
Availability under combined facilities
Maximum borrowing capacity	1,420,000,000
Amounts outstanding	272,000,000
Net availability	1,148,000,000
Letter of credit
Availability under combined facilities
Amounts outstanding	195,000,000
Letter of credit | DTE Electric
Availability under combined facilities
Amounts outstanding	0
Letter of credit | DTE Gas
Availability under combined facilities
Amounts outstanding	0
Letter of credit | DTE Energy
Availability under combined facilities
Amounts outstanding	195,000,000
Letter of credit | Unsecured letter of credit facility, expiring in February 2021
Availability under combined facilities
Maximum borrowing capacity	150,000,000
Letter of credit | Unsecured letter of credit facility, expiring in February 2021 | DTE Electric
Availability under combined facilities
Maximum borrowing capacity	0
Letter of credit | Unsecured letter of credit facility, expiring in February 2021 | DTE Gas
Availability under combined facilities
Maximum borrowing capacity	0
Letter of credit | Unsecured letter of credit facility, expiring in February 2021 | DTE Energy
Availability under combined facilities
Maximum borrowing capacity	150,000,000	$ 150,000,000
Letter of credit | Unsecured letter of credit facility, expiring in September 2019
Availability under combined facilities
Maximum borrowing capacity	70,000,000
Letter of credit | Unsecured letter of credit facility, expiring in September 2019 | DTE Electric
Availability under combined facilities
Maximum borrowing capacity	0
Letter of credit | Unsecured letter of credit facility, expiring in September 2019 | DTE Gas
Availability under combined facilities
Maximum borrowing capacity	0
Letter of credit | Unsecured letter of credit facility, expiring in September 2019 | DTE Energy
Availability under combined facilities
Maximum borrowing capacity	70,000,000
Revolving credit facility | Unsecured revolving credit facility, expiring April 2022
Availability under combined facilities
Maximum borrowing capacity	1,900,000,000
Revolving credit facility | Unsecured revolving credit facility, expiring April 2022 | DTE Electric
Availability under combined facilities
Maximum borrowing capacity	400,000,000
Revolving credit facility | Unsecured revolving credit facility, expiring April 2022 | DTE Gas
Availability under combined facilities
Maximum borrowing capacity	300,000,000
Revolving credit facility | Unsecured revolving credit facility, expiring April 2022 | DTE Energy
Availability under combined facilities
Maximum borrowing capacity	1,200,000,000
Commercial paper issuances
Availability under combined facilities
Amounts outstanding	156,000,000
Commercial paper issuances | DTE Electric
Availability under combined facilities
Amounts outstanding	0
Commercial paper issuances | DTE Gas
Availability under combined facilities
Amounts outstanding	79,000,000
Commercial paper issuances | DTE Energy
Availability under combined facilities
Amounts outstanding	$ 77,000,000

Leases Leases (Details Textuals

Leases Leases (Details Textuals) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2019USD ($)agreement	Dec. 31, 2018USD ($)agreement	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Lessee, Lease, Description [Line Items]
Short-term leases expense	$ 2
Term of finance lease contract	20 years
Finance lease contract, renewal option extension term	5 years
Percent ownership interest in Vector Pipeline	40.00%
Number of energy services agreements | agreement	2
Depreciation expense associated with property under operating leases	$ 8
Interest income recognized under finance leases	$ 1
Contingent rental revenues		$ 107	$ 91	$ 101
Pipeline System Lease
Lessee, Lease, Description [Line Items]
Percent ownership interest in Vector Pipeline		40.00%
Number of energy services agreements | agreement		2
Lessor capital lease renewal terms		5 years
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
Lessee, Lease, Description [Line Items]
Short-term leases expense	$ 1
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	3 Months Ended
	Mar. 31, 2019USD ($)
Lessee, Lease, Description [Line Items]
Operating lease cost	$ 11
Finance lease cost:
Amortization of right-of-use assets	1
Interest of lease liabilities	0
Total finance lease cost	1
Variable lease cost	5
Total lease cost	17
DTE Electric
Lessee, Lease, Description [Line Items]
Operating lease cost	4
Finance lease cost:
Amortization of right-of-use assets	1
Interest of lease liabilities	0
Total finance lease cost	1
Variable lease cost	0
Total lease cost	$ 5

Leases (Other Information) (Det

Leases (Other Information) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Cash paid for amounts included in the measurement of these liabilities:
Operating cash flows from finance leases	$ 1
Operating cash flows from operating leases	10
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	$ 11
Weighted Average Remaining Lease Term
Operating leases	9 years 1 month 6 days
Finance leases	2 years 8 months 12 days
Weighted Average Discount Rate
Operating leases	3.80%
Finance leases	3.00%
DTE Electric
Cash paid for amounts included in the measurement of these liabilities:
Operating cash flows from finance leases	$ 1
Operating cash flows from operating leases	3
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	$ 0
Weighted Average Remaining Lease Term
Operating leases	10 years 4 months 24 days
Finance leases	2 years 8 months 12 days
Weighted Average Discount Rate
Operating leases	3.60%
Finance leases	3.00%

Leases (Future Minimum Lease Pa

Leases (Future Minimum Lease Payments - Topic 842) (Details) $ in Millions	Mar. 31, 2019USD ($)
Operating Leases
2019	$ 28
2020	30
2021	22
2022	16
2023	13
2024 and thereafter	50
Total future minimum lease payments	159
Imputed interest	(28)
Total	131
Finance Leases
2019	3
2020	4
2021	3
2022	0
2023	0
2024 and thereafter	0
Total future minimum lease payments	10
Imputed interest	0
Total	10
DTE Electric
Operating Leases
2019	12
2020	12
2021	11
2022	7
2023	6
2024 and thereafter	30
Total future minimum lease payments	78
Imputed interest	(14)
Total	64
Finance Leases
2019	3
2020	4
2021	3
2022	0
2023	0
2024 and thereafter	0
Total future minimum lease payments	10
Imputed interest	0
Total	$ 10

Leases (Finance Leases Reported

Leases (Finance Leases Reported on Consolidated Statements of Financial Position) (Details) $ in Millions	Mar. 31, 2019USD ($)
Lessee, Lease, Description [Line Items]
Right-of-use assets, within Property, plant, and equipment, net	$ 10
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	10
Current lease liabilities, within Current Liabilities — Other	$ 4

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 (Lease Income Associated

Leases (Lease Income Associated with Operating Leases) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Leases [Abstract]
Fixed payments	$ 17
Variable payments	27
Total lease income under operating leases	$ 44

Leases (Minimum Future Rental R

Leases (Minimum Future Rental Revenues under Operating Leases) (Details) $ in Millions	Mar. 31, 2019USD ($)
Leases [Abstract]
2019	$ 50
2020	67
2021	65
2022	22
2023	22
2024 and thereafter	216
Total minimum future rental revenues under operating leases	$ 442

Leases (Property under Operatin

Leases (Property under Operating Leases - Topic 842) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Lessor, Lease, Description [Line Items]
Gross property under operating leases	$ 32,214	$ 31,810
Accumulated amortization of property under operating leases	10,350	$ 10,160
Property Under Operating Leases
Lessor, Lease, Description [Line Items]
Gross property under operating leases	442
Accumulated amortization of property under operating leases	$ 154

Leases (Components of Net Inves

Leases (Components of Net Investment in Finance Leases) (Details) $ in Millions	Mar. 31, 2019USD ($)
Leases [Abstract]
2019	$ 7
2020	9
2021	0
2022	0
2023	0
2024 and thereafter	1
Total minimum future lease receipts	17
Residual value of leased pipeline	40
Less unearned income	8
Net investment in finance lease	49
Less current portion	5
Net investment in finance lease, noncurrent	$ 44

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 (

Commitments and Contingencies (Details Textuals)	3 Months Ended	12 Months Ended
	Mar. 31, 2019USD ($)employeefacilityNOVplantsite	Dec. 31, 2018USD ($)	Jul. 31, 2009plant
Loss Contingencies [Line Items]
Unrecorded unconditional purchase obligation	$ 3,900,000,000
Long-lived assets used in producing electric output for sale	$ 21,864,000,000	$ 21,650,000,000
Power and Industrial Projects
Loss Contingencies [Line Items]
Number of generating plants operated with ownership interest held | plant	5
Workforce subject to collective bargaining arrangements | Labor force concentration risk
Loss Contingencies [Line Items]
Number of employees | employee	5,200
Pacific Gas and Electric Corporation | Power and Industrial Projects
Loss Contingencies [Line Items]
Long-lived assets used in producing electric output for sale	$ 105,000,000
Equity investments, including note receivable	$ 74,000,000
Impairment loss		0
Other than temporary decline in equity investments		0
Synthetic fuel
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	$ 380,000,000
NEXUS pipeline | DTE Gas
Loss Contingencies [Line Items]
Maximum potential liability	$ 242,000,000
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	$ 377,000,000
Percentage of payment obligations due	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 payment obligations due	50.00%
Guarantee termination, minimum threshold, period following end of primary term of capacity lease agreements	15 years
NEXUS pipeline | Generation Pipeline, LLC
Loss Contingencies [Line Items]
Maximum potential liability	$ 15,000,000
Other guarantees
Loss Contingencies [Line Items]
Maximum potential liability	64,000,000
Performance surety bonds
Loss Contingencies [Line Items]
Performance bonds outstanding	$ 76,000,000
Reduction of Carbon Emissions by Early 2020s
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 in violation | plant			5
Number of NOVs/FOVs | NOV	2
Environmental capital expenditures through prior year end		2,400,000,000
Number of former MGP sites | site	3
Accrued for remediation	$ 8,000,000	7,000,000
Number of permitted engineered ash storage facilities owned | facility	3
Unrecorded unconditional purchase obligation	$ 2,200,000,000
Long-lived assets used in producing electric output for sale	$ 15,658,000,000	15,437,000,000
DTE Electric | Workforce subject to collective bargaining arrangements | Labor force concentration risk
Loss Contingencies [Line Items]
Number of employees | employee	2,800
DTE Gas
Loss Contingencies [Line Items]
Number of former MGP sites | site	14
Accrued for remediation	$ 30,000,000	$ 25,000,000
Amortization period (in years)	10 years
DTE Gas | NEXUS pipeline | DTE Gas
Loss Contingencies [Line Items]
Percentage of payment obligations due	50.00%
DTE Gas | Clean up completed and site closed
Loss Contingencies [Line Items]
Number of former MGP sites | site	6
DTE Gas | Partial closure complete
Loss Contingencies [Line Items]
Number of former MGP sites | site	6
NEXUS | NEXUS pipeline | DTE Gas
Loss Contingencies [Line Items]
Agreement term	15 years
NEXUS | NEXUS pipeline | Texas Eastern Transmission, LP
Loss Contingencies [Line Items]
Agreement term	15 years
NEXUS | NEXUS pipeline | Vector
Loss Contingencies [Line Items]
Agreement term	15 years

Retirement Benefits and Trust_3

Retirement Benefits and Trusteed Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 21	$ 25
Interest cost	55	50
Expected return on plan assets	(81)	(82)
Amortization of net actuarial loss	32	44
Amortization of prior service credit	0	0
Net periodic benefit cost (credit)	27	37
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	5	7
Interest cost	18	17
Expected return on plan assets	(31)	(36)
Amortization of net actuarial loss	3	3
Amortization of prior service credit	(2)	0
Net periodic benefit cost (credit)	(7)	(9)
Other Postretirement Benefits | DTE Electric
Defined Benefit Plan Disclosure [Line Items]
Service cost	4	5
Interest cost	13	13
Expected return on plan assets	(21)	(24)
Amortization of net actuarial loss	1	2
Amortization of prior service credit	(1)	0
Net periodic benefit cost (credit)	$ (4)	$ (4)

Retirement Benefits and Trust_4

Retirement Benefits and Trusteed Assets (Details Textuals) - USD ($)	1 Months Ended	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2019	Mar. 31, 2018
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Maximum contribution amount	$ 50,000,000	$ 50,000,000
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Maximum contribution amount	0	0
DTE Electric | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Pension cost	$ 100,000,000	$ 23,000,000	$ 30,000,000

Retirement Benefits and Trust_5

Retirement Benefits and Trusteed Assets - VEBA Contributions (Details) - USD ($) $ / shares in Units, $ in Millions	Mar. 05, 2019	Mar. 31, 2019	Mar. 31, 2018
Defined Contribution Plan Disclosure [Line Items]
Amount		$ 100	$ 175
Pension Benefits
Defined Contribution Plan Disclosure [Line Items]
Number of Shares (in shares)	814,597
Price per Share (in dollars per share)	$ 122.76
Amount	$ 100

Segment and Related Informati_3

Segment and Related Information (Details Textuals) customer in Millions	Mar. 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
	Mar. 31, 2019	Mar. 31, 2018
Segment Reporting Information [Line Items]
Revenues	$ (3,514)	$ (3,753)
Electric
Segment Reporting Information [Line Items]
Revenues	(1,235)	(1,205)
Gas
Segment Reporting Information [Line Items]
Revenues	(645)	(550)
Gas Storage and Pipelines
Segment Reporting Information [Line Items]
Revenues	(116)	(119)
Power and Industrial Projects
Segment Reporting Information [Line Items]
Revenues	(388)	(567)
Energy Trading
Segment Reporting Information [Line Items]
Revenues	(1,301)	(1,498)
Reconciliation and Eliminations
Segment Reporting Information [Line Items]
Revenues	172	186
Reconciliation and Eliminations | Electric
Segment Reporting Information [Line Items]
Revenues	14	13
Reconciliation and Eliminations | Gas
Segment Reporting Information [Line Items]
Revenues	2	2
Reconciliation and Eliminations | Gas Storage and Pipelines
Segment Reporting Information [Line Items]
Revenues	3	8
Reconciliation and Eliminations | Power and Industrial Projects
Segment Reporting Information [Line Items]
Revenues	145	155
Reconciliation and Eliminations | Energy Trading
Segment Reporting Information [Line Items]
Revenues	7	7
Reconciliation and Eliminations | Corporate and Other
Segment Reporting Information [Line Items]
Revenues	$ 1	$ 1

Segment and Related Informati_5

Segment and Related Information (Financial Data - Operating Revenues including Inter-segment Revenues) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues — Utility operations	$ 1,864	$ 1,740
Operating Revenues — Non-utility operations	1,650	2,013
Operating Revenues	3,514	3,753
Reconciliation and Eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues — Non-utility operations	(172)	(186)
Operating Revenues	(172)	(186)
Electric
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues	1,235	1,205
Electric | Operating segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues — Utility operations	1,235	1,205
Electric | Reconciliation and Eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues	(14)	(13)
Gas
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues	645	550
Gas | Operating segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues — Utility operations	645	550
Gas | Reconciliation and Eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues	(2)	(2)
Gas Storage and Pipelines
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues	116	119
Gas Storage and Pipelines | Operating segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues — Non-utility operations	116	119
Gas Storage and Pipelines | Reconciliation and Eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues	(3)	(8)
Power and Industrial Projects
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues	388	567
Power and Industrial Projects | Operating segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues — Non-utility operations	388	567
Power and Industrial Projects | Reconciliation and Eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues	(145)	(155)
Energy Trading
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues	1,301	1,498
Energy Trading | Operating segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues — Non-utility operations	1,301	1,498
Energy Trading | Reconciliation and Eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues	(7)	(7)
Corporate and Other | Operating segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues — Non-utility operations	1	0
Corporate and Other | Reconciliation and Eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating Revenues	$ (1)	$ (1)

Segment and Related Informati_6

Segment and Related Information (Financial Data - Net Income (Loss) Attributable to DTE Energy by Segment) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net Income Attributable to DTE Energy Company	$ 401	$ 361
Electric
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net Income Attributable to DTE Energy Company	147	140
Gas
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net Income Attributable to DTE Energy Company	151	104
Gas Storage and Pipelines
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net Income Attributable to DTE Energy Company	48	62
Power and Industrial Projects
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net Income Attributable to DTE Energy Company	26	45
Energy Trading
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net Income Attributable to DTE Energy Company	32	31
Corporate and Other
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net Income Attributable to DTE Energy Company	$ (3)	$ (21)