Retirement Benefits and Trusteed Assets (Fair Value Measurement Amounts for Pension Plan Assets) (Details) - Pension Plan - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	$ 3,795	$ 3,758	$ 3,960
Short-term Investments
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	83	97
Equity Securities, Domestic
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	343	349
Equity Securities, International
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	243	223
Fixed Income Securities, Governmental
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	618	703
Fixed Income Securities, Corporate
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	1,504	1,350
Hedge Funds and Similar Investments
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	324	318
Private Equity and Other
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	680	718
Level 1
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	792	896
Level 1 | Short-term Investments
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	83	97
Level 1 | Equity Securities, Domestic
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	0	0
Level 1 | Equity Securities, International
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	34	35
Level 1 | Fixed Income Securities, Governmental
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	537	627
Level 1 | Fixed Income Securities, Corporate
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	0	0
Level 1 | Hedge Funds and Similar Investments
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	138	137
Level 1 | Private Equity and Other
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	0	0
Level 2
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	1,599	1,440
Level 2 | Short-term Investments
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	0	0
Level 2 | Equity Securities, Domestic
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	0	0
Level 2 | Equity Securities, International
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	0	0
Level 2 | Fixed Income Securities, Governmental
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	81	76
Level 2 | Fixed Income Securities, Corporate
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	1,504	1,350
Level 2 | Hedge Funds and Similar Investments
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	14	14
Level 2 | Private Equity and Other
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	0	0
Other
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	1,404	1,422
Other | Short-term Investments
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	0	0
Other | Equity Securities, Domestic
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	343	349
Other | Equity Securities, International
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	209	188
Other | Fixed Income Securities, Governmental
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	0	0
Other | Fixed Income Securities, Corporate
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	0	0
Other | Hedge Funds and Similar Investments
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	172	167
Other | Private Equity and Other
Defined Benefit Plan Disclosure [Line Items]
DTE Energy Total	$ 680	$ 718