Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Basic Earnings per Share
Net Income Attributable to DTE Energy Company	$ 397	$ 340
Less: Allocation of earnings to net restricted stock awards	0	1
Net income available to common shareholders — basic	$ 397	$ 339
Average number of common shares outstanding — basic (in shares)	194.0	192.0
Basic Earnings per Common Share (in dollars per share)	$ 2.05	$ 1.77
Diluted Earnings per Share
Net Income Attributable to DTE Energy Company	$ 397	$ 340
Less: Allocation of earnings to net restricted stock awards	0	1
Net income available to common shareholders — diluted	$ 397	$ 339
Average number of common shares outstanding — diluted (in shares)	194.0	192.0
Diluted Earnings per Common Share (in dollars per share)	$ 2.05	$ 1.76
Antidilutive securities excluded from computation of earnings per share (in shares)	10.3	10.3