Fair Value (Fair Value and Unrealized Gains and Losses for the Nuclear Decommissioning Trust Funds) (Details) - DTE Electric - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Fair Value	$ 2,246	$ 2,256
Unrealized Gains	663	687
Unrealized Losses	(60)	(58)
Cash equivalents
Debt Securities, Available-for-sale [Line Items]
Fair Value	28	26
Unrealized Gains	0	0
Unrealized Losses	0	0
Private equity and other
Debt Securities, Available-for-sale [Line Items]
Fair Value	344	349
Unrealized Gains	99	106
Unrealized Losses	(7)	(8)
Hedge funds and similar investments
Debt Securities, Available-for-sale [Line Items]
Fair Value	231	228
Unrealized Gains	5	7
Unrealized Losses	(6)	(5)
Equity securities
Debt Securities, Available-for-sale [Line Items]
Fair Value	986	1,003
Unrealized Gains	542	558
Unrealized Losses	(22)	(16)
Fixed income securities
Debt Securities, Available-for-sale [Line Items]
Fair Value	657	650
Unrealized Gains	17	16
Unrealized Losses	$ (25)	$ (29)