Fair Value (Fair Value and Unrealized Gains and Losses for the Nuclear Decommissioning Trust Funds) (Details) - DTE Electric - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Fair Value	$ 2,134	$ 2,041
Unrealized Gains	621	545
Unrealized Losses	(59)	(58)
Cash equivalents
Debt Securities, Available-for-sale [Line Items]
Fair Value	39	34
Unrealized Gains	0	0
Unrealized Losses	0	0
Private equity and other
Debt Securities, Available-for-sale [Line Items]
Fair Value	328	312
Unrealized Gains	86	74
Unrealized Losses	(8)	(8)
Hedge funds and similar investments
Debt Securities, Available-for-sale [Line Items]
Fair Value	192	184
Unrealized Gains	7	4
Unrealized Losses	(8)	(9)
Equity securities
Debt Securities, Available-for-sale [Line Items]
Fair Value	982	921
Unrealized Gains	517	459
Unrealized Losses	(11)	(11)
Fixed income securities
Debt Securities, Available-for-sale [Line Items]
Fair Value	593	590
Unrealized Gains	11	8
Unrealized Losses	$ (32)	$ (30)