Retirement Benefits and Trusteed Assets (Contributions to DTE Energy Company Affiliates Employee Benefit Plans Master Trust) (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended
	Sep. 08, 2020	Sep. 30, 2020	Mar. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contribution of common stock to pension plan		$ 82	$ 100
Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Number of Shares (in shares)	694,444
Price per Share (in dollars per share)	$ 118.08
Contribution of common stock to pension plan	$ 82