Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Basic Earnings per Share
Net Income Attributable to DTE Energy Company	$ 334	$ 270	$ 929	$ 847
Less: Allocation of earnings to net restricted stock awards	1	1	2	2
Net income available to common shareholders — basic	$ 333	$ 269	$ 927	$ 845
Average number of common shares outstanding — basic (in shares)	182.0	179.0	181.0	179.0
Basic Earnings per Common Share (in dollars per share)	$ 1.84	$ 1.51	$ 5.13	$ 4.72
Diluted Earnings per Share
Net Income Attributable to DTE Energy Company	$ 334	$ 270	$ 929	$ 847
Less: Allocation of earnings to net restricted stock awards	1	1	2	2
Net income available to common shareholders — diluted	$ 333	$ 269	$ 927	$ 845
Average number of common shares outstanding — diluted (in shares)	182.0	179.0	181.0	179.0
Diluted Earnings per Common Share (in dollars per share)	$ 1.84	$ 1.51	$ 5.13	$ 4.72
Antidilutive securities excluded from computation of earnings per share (in shares)	6.2	6.2	6.4	6.4