Fair Value (Fair Value and Unrealized Gains and Losses for the Nuclear Decommissioning Trust Funds) (Details) - DTE Electric - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Fair Value	$ 2,261	$ 2,041
Unrealized Gains	701	545
Unrealized Losses	(44)	(58)
Cash equivalents
Debt Securities, Available-for-sale [Line Items]
Fair Value	31	34
Unrealized Gains	0	0
Unrealized Losses	0	0
Private equity and other
Debt Securities, Available-for-sale [Line Items]
Fair Value	350	312
Unrealized Gains	102	74
Unrealized Losses	(8)	(8)
Hedge funds and similar investments
Debt Securities, Available-for-sale [Line Items]
Fair Value	222	184
Unrealized Gains	9	4
Unrealized Losses	(4)	(9)
Equity securities
Debt Securities, Available-for-sale [Line Items]
Fair Value	1,008	921
Unrealized Gains	568	459
Unrealized Losses	(11)	(11)
Fixed income securities
Debt Securities, Available-for-sale [Line Items]
Fair Value	650	590
Unrealized Gains	22	8
Unrealized Losses	$ (21)	$ (30)