Financial and Other Derivative Instruments (Details Textuals) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Derivative [Line Items]
Total derivative assets, gross	$ 707	$ 694
Letters of credit that could be used to offset net derivative liabilities	2	1
Letters of credit that could be used to offset net derivative assets	17	0
Additional collateral, aggregate fair value	483
Derivative net liability position aggregate fair value	491
Collateral already posted fair value	3
Derivative, net asset position, fair value	426
Remaining amount of offsets to derivative net liability positions for hard and soft trigger provisions	62
Derivatives not designated as hedging instruments
Derivative [Line Items]
Total derivative assets, gross	704	674
Other current assets | Derivative assets — FTRs | Derivatives not designated as hedging instruments | DTE Electric
Derivative [Line Items]
Total derivative assets, gross	$ 11	$ 9