Income Taxes (Components of Income Tax Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current income tax expense (benefit)
Federal	$ (1)	$ (3)	$ (16)
State and other income tax	7	(4)	24
Total current income taxes	6	(7)	8
Deferred income tax expense
Federal	184	178	289
State and other income tax	81	59	67
Total deferred income taxes	265	237	356
Total	271	230	364
DTE Electric
Current income tax expense (benefit)
Federal	0	(26)	(19)
State and other income tax	11	(2)	20
Total current income taxes	11	(28)	1
Deferred income tax expense
Federal	268	252	251
State and other income tax	74	68	46
Total deferred income taxes	342	320	297
Total	$ 353	$ 292	$ 298