Fair Value (Realized Gains and Losses and Proceeds from Sale of Securities by Nuclear Decommissioning Trust Funds) (Details) - DTE Electric - Nuclear decommissioning trusts - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Realized gains	$ 50	$ 47	$ 36
Realized losses	(32)	(27)	(42)
Proceeds from sale of securities	$ 717	$ 555	$ 681