Retirement Benefits and Trusteed Assets (OPEB - Postretirement Cost Inclusions) (Details) - Other postretirement benefit plan - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 27	$ 30	$ 26
Interest cost	48	46	56
Expected return on plan assets	(126)	(129)	(128)
Amortization of:
Net actuarial loss	4	13	16
Prior service credit	(19)	(19)	(19)
Net pension cost/other postretirement cost (credit)	(66)	(59)	(49)
DTE Electric
Defined Benefit Plan Disclosure [Line Items]
Service cost	20	23	20
Interest cost	37	35	43
Expected return on plan assets	(85)	(86)	(87)
Amortization of:
Net actuarial loss	5	11	11
Prior service credit	(14)	(14)	(14)
Net pension cost/other postretirement cost (credit)	$ (37)	$ (31)	$ (27)