Retirement Benefits and Trusteed Assets (OPEB - Benefits related to Qualified and Nonqualified Pension Plans Expected to be paid in the Next Ten Years) (Details) - Other postretirement benefit plan $ in Millions	Dec. 31, 2021 USD ($)
Defined Benefit Plan Disclosure [Line Items]
2022	$ 85
2023	89
2024	91
2025	94
2026	95
2027-2031	493
Total	947
DTE Electric
Defined Benefit Plan Disclosure [Line Items]
2022	64
2023	68
2024	69
2025	71
2026	72
2027-2031	375
Total	$ 719