Leases (Components of Lease Cost) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Lessee, Lease, Description [Line Items]
Operating lease cost	$ 26	$ 22	$ 18
Finance lease cost:
Amortization of right-of-use assets	4	7	7
Interest of lease liabilities	1	0	1
Total finance lease cost	5	7	8
Variable lease cost	17	13	9
Short-term lease cost	18	12	19
Total lease cost	66	54	54
DTE Electric
Lessee, Lease, Description [Line Items]
Operating lease cost	22	17	12
Finance lease cost:
Amortization of right-of-use assets	3	6	6
Interest of lease liabilities	1	0	0
Total finance lease cost	4	6	6
Variable lease cost	0	0	0
Short-term lease cost	10	4	10
Total lease cost	$ 36	$ 27	$ 28