Leases (Components of Lease Cost) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Lessee, Lease, Description [Line Items]
Operating lease cost	$ 22	$ 18	$ 19
Finance lease cost:
Amortization of right-of-use assets	7	7	7
Interest of lease liabilities	0	1	1
Total finance lease cost	7	8	8
Variable lease cost	13	9	9
Short-term lease cost	12	19	14
Total lease cost	54	54	50
DTE Electric
Lessee, Lease, Description [Line Items]
Operating lease cost	17	12	14
Finance lease cost:
Amortization of right-of-use assets	6	6	6
Interest of lease liabilities	0	0	0
Total finance lease cost	6	6	6
Variable lease cost	0	0	0
Short-term lease cost	4	10	6
Total lease cost	$ 27	$ 28	$ 26