Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Basic Earnings per Share
Net Income Attributable to DTE Energy Company	$ 340	$ 401
Less: Allocation of earnings to net restricted stock awards	1	1
Net income available to common shareholders — basic	$ 339	$ 400
Average number of common shares outstanding — basic (in shares)	192.0	182.0
Basic Earnings per Common Share (in dollars per share)	$ 1.77	$ 2.20
Diluted Earnings per Share
Net Income Attributable to DTE Energy Company	$ 340	$ 401
Less: Allocation of earnings to net restricted stock awards	1	1
Net income available to common shareholders — diluted	$ 339	$ 400
Average number of common shares outstanding — basic (in shares)	192.0	182.0
Incremental shares attributable to:
Average dilutive equity units, performance share awards, and stock options (in shares)	0.0	1.0
Average number of common shares outstanding — diluted (in shares)	192.0	183.0
Diluted Earnings per Common Share (in dollars per share)	$ 1.76	$ 2.19
Antidilutive securities excluded from computation of earnings per share (in shares)	9.7