Leases (Future Minimum Lease Payments) (Details) $ in Millions	Dec. 31, 2021 USD ($)
Operating Leases
2022	$ 16
2023	13
2024	11
2025	8
2026	7
2027 and thereafter	56
Total future minimum lease payments	111
Imputed interest	(23)
Lease liabilities	88
Finance Leases
2022	8
2023	9
2024	3
2025	1
2026	1
2027 and thereafter	8
Total future minimum lease payments	30
Imputed interest	(3)
Lease liabilities	27
DTE Electric
Operating Leases
2022	12
2023	10
2024	8
2025	6
2026	5
2027 and thereafter	27
Total future minimum lease payments	68
Imputed interest	(12)
Lease liabilities	56
Finance Leases
2022	6
2023	6
2024	1
2025	0
2026	0
2027 and thereafter	0
Total future minimum lease payments	13
Imputed interest	0
Lease liabilities	$ 13