Related Party Transactions (Schedule of Related Party Transactions) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Related Party Transaction [Line Items]
Operating Revenues — Utility operations	$ 1,844	$ 1,656	$ 5,119	$ 4,937
Fuel, purchased power, and gas — utility	455	400	1,296	1,342
Fuel, purchased power, and gas — non-utility	1,180	1,257	2,937	3,900
DTE Electric
Related Party Transaction [Line Items]
Operating Revenues — Utility operations	1,690	1,519	4,211	3,944
Fuel, purchased power, and gas — utility	451	399	1,090	1,067
NEXUS | DTE Gas | Equity Method Investee
Related Party Transaction [Line Items]
Operating Revenues — Utility operations	8	8	24	24
Fuel, purchased power, and gas — utility	2	2	14	15
NEXUS | DTE Electric | Equity Method Investee
Related Party Transaction [Line Items]
Fuel, purchased power, and gas — utility	2	2	6	6
NEXUS | DTE Energy Trading | Equity Method Investee
Related Party Transaction [Line Items]
Fuel, purchased power, and gas — non-utility	$ 7	$ 2	$ 20	$ 5