Retirement Benefits and Trusteed Assets (OPEB - Other Changes in Plan Assets and APBO Recognized in Regulatory Assets and OCI) (Details) - Other postretirement benefit plan - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Other changes in plan assets and accumulated postretirement benefit obligation recognized in Regulatory assets and liabilities and Other comprehensive income (loss)
Net actuarial gain	$ (103)	$ (17)
Amortization of net actuarial loss	(6)	(10)
Amortization of prior service credit	10	19
Total recognized in Regulatory assets and liabilities and Other comprehensive income (loss)	(99)	(8)
Total recognized in net periodic pension credit, Regulatory assets, and Other comprehensive income (loss)	(143)	(46)
DTE Electric
Other changes in plan assets and accumulated postretirement benefit obligation recognized in Regulatory assets and liabilities and Other comprehensive income (loss)
Net actuarial gain	(98)	(6)
Amortization of net actuarial loss	(1)	(1)
Amortization of prior service credit	6	14
Total recognized in Regulatory assets and liabilities and Other comprehensive income (loss)	(93)	7
Total recognized in net periodic pension credit, Regulatory assets, and Other comprehensive income (loss)	$ (116)	$ (17)