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