Retirement Benefits and Trusteed Assets (Details Textuals) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended
	Mar. 31, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Cash contributions made by employer				$ 50,000,000
Additional contributions anticipated, remainder of fiscal year		$ 0		0
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Additional contributions anticipated, remainder of fiscal year		0		0
DTE Electric | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Pension cost	$ 100,000,000	$ 23,000,000	$ 30,000,000	$ 68,000,000	$ 90,000,000