Income Taxes (Tables)

12 Months Ended

Dec. 31, 2017

Income Tax Disclosure [Abstract]

Schedule of Effective Income Tax Rate Reconciliation

The Registrants' total Income Tax Expense varied from the statutory federal income tax rate for the following reasons:

	2017			2016			2015
DTE Energy	(In millions)
Income Before Income Taxes	$	1,287		$	1,105		$	950
Income tax expense at 35% statutory rate	$	450		$	387		$	333
Production tax credits	(189		)	(145		)	(122		)
Investment tax credits	(4		)	(5		)	(7		)
Depreciation	(4		)	(4		)	(4		)
Noncontrolling interests	8			12			2
AFUDC equity	(18		)	(10		)	(8		)
Employee Stock Ownership Plan dividends	(5		)	(5		)	(5		)
Stock based compensation	(14		)	—			—
Subsidiary stock loss	—			(10		)	—
State and local income taxes, net of federal benefit	51			58			35
Enactment of the Tax Cuts and Jobs Act	(105		)	—			—
Other, net	5			(7		)	6
Income Tax Expense	$	175		$	271		$	230
Effective income tax rate	13.6		%	24.5		%	24.2		%

	2017			2016			2015
DTE Electric	(In millions)
Income Before Income Taxes	$	928		$	975		$	836
Income tax expense at 35% statutory rate	$	325		$	341		$	293
Production tax credits	(36		)	(30		)	(31		)
Investment tax credits	(4		)	(4		)	(5		)
Depreciation	3			3			3
AFUDC equity	(5		)	(6		)	(7		)
Employee Stock Ownership Plan dividends	(3		)	(3		)	(3		)
State and local income taxes, net of federal benefit	48			56			43
Other, net	(1		)	(4		)	(1		)
Income Tax Expense	$	327		$	353		$	292
Effective income tax rate	35.2		%	36.2		%	34.9		%

Schedule of Components of Income Tax Expense (Benefit)

Components of the Registrants' Income Tax Expense were as follows:

	2017			2016			2015
DTE Energy	(In millions)
Current income tax expense (benefit)
Federal	$	(22	)	$	(1	)	$	(3	)
State and other income tax	1			7			(4		)
Total current income taxes	(21		)	6			(7		)
Deferred income tax expense
Federal	118			184			178
State and other income tax	78			81			59
Total deferred income taxes	196			265			237
	$	175		$	271		$	230

	2017			2016		2015
DTE Electric	(In millions)
Current income tax expense (benefit)
Federal	$	(17	)	$	—	$	(26	)
State and other income tax	(1		)	11		(2		)
Total current income taxes	(18		)	11		(28		)
Deferred income tax expense
Federal	270			268		252
State and other income tax	75			74		68
Total deferred income taxes	345			342		320
	$	327		$	353	$	292

Schedule of Deferred Tax Assets and Liabilities

The Registrants' deferred tax assets (liabilities) were comprised of the following at December 31:

	DTE Energy						DTE Electric
	2017			2016			2017			2016
	(In millions)
Property, plant, and equipment	$	(3,276	)	$	(4,880	)	$	(2,698	)	$	(3,819	)
Regulatory assets and liabilities	(94		)	(879		)	(31		)	(778		)
Tax credit carry-forwards	947			643			193			116
Pension and benefits	334			643			302			518
Federal net operating loss carry-forward	83			190			47			42
State and local net operating loss carry-forwards	70			59			5			1
Investments in equity method investees	(82		)	(119		)	—			—
Other	170			217			94			127
	(1,848		)	(4,126		)	(2,088		)	(3,793		)
Less valuation allowance	(40		)	(36		)	—			—
Long-term deferred income tax liabilities	$	(1,888	)	$	(4,162	)	$	(2,088	)	$	(3,793	)
Deferred income tax assets	$	1,814		$	1,463		$	830		$	569
Deferred income tax liabilities	(3,702		)	(5,625		)	(2,918		)	(4,362		)
	$	(1,888	)	$	(4,162	)	$	(2,088	)	$	(3,793	)

Schedule of Unrecognized Tax Benefits Roll Forward

A reconciliation of the beginning and ending amount of unrecognized tax benefits for the Registrants is as follows:

	2017		2016		2015
DTE Energy	(In millions)
Balance at January 1	$	10	$	3	$	9
Additions for tax positions of prior years	—		7		—
Lapse of statute of limitations	—		—		(6		)
Balance at December 31	$	10	$	10	$	3

	2017		2016		2015
DTE Electric	(In millions)
Balance at January 1	$	13	$	4	$	4
Additions for tax positions of prior years	—		9		—
Balance at December 31	$	13	$	13	$	4