Fair Value (Realized Gains and Losses and Proceeds from Sale of Securities by Nuclear Decommissioning Trust Funds) (Details) - DTE Electric - Nuclear decommissioning trust fund - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Debt Securities, Available-for-sale [Line Items]
Realized gains	$ 27	$ 27	$ 102	$ 40
Realized losses	(8)	(9)	(21)	(26)
Proceeds from sale of securities	$ 163	$ 221	$ 638	$ 592