Regulatory Matters (Tables)

12 Months Ended

Dec. 31, 2017

Regulatory Assets and Liabilities Disclosure [Abstract]

Schedule of Regulatory Assets

The following are balances and a brief description of the Registrants' Regulatory assets and liabilities at December 31:

	DTE Energy						DTE Electric
	2017			2016			2017			2016
Assets	(In millions)
Recoverable pension and other postretirement costs
Pension	$	2,000		$	2,159		$	1,502		$	1,642
Other postretirement costs	278			286			211			207
Asset retirement obligation	569			613			569			613
Removal costs asset	299			193			299			193
Recoverable Michigan income taxes	213			231			171			187
Deferred environmental costs	75			78			—			—
Unamortized loss on reacquired debt	65			59			46			39
Transitional Reconciliation Mechanism	46			30			46			30
Customer360 deferred costs	45			33			45			33
Recoverable income taxes related to AFUDC equity	41			59			35			53
Other recoverable income taxes	26			57			26			57
Nuclear Performance Evaluation and Review Committee Tracker	22			—			22			—
Accrued PSCR/GCR revenue	17			22			17			19
Other	82			93			66			76
	3,778			3,913			3,055			3,149
Less amount included in Current Assets	(55		)	(42		)	(50		)	(36		)
	$	3,723		$	3,871		$	3,005		$	3,113

Schedule of Regulatory Liabilities

	DTE Energy						DTE Electric
	2017			2016			2017			2016
Liabilities	(In millions)
Refundable federal income taxes	$	2,384		$	—		$	1,946		$	—
Removal costs liability	265			266			—			—
Renewable energy	112			145			112			145
Negative other postretirement offset	80			56			67			55
Negative pension offset	21			36			—			—
Fermi 2 refueling outage	15			27			15			27
Refundable self-implemented rates	2			27			2			27
Other	14			32			12			2
	2,893			589			2,154			256
Less amount included in Current Liabilities	(18		)	(34		)	(17		)	(27		)
	$	2,875		$	555		$	2,137		$	229