v3.26.1
Fair Value (Reconciliation of Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]        
Net Assets (Liabilities) as of December 31 $ (69) $ (89) $ 19 $ 13
Transfers into Level 3 from Level 2 0 2 0 4
Transfers from Level 3 into Level 2     0 2
Total gains (losses)        
Included in earnings 69 164 (86) 105
Recorded in Regulatory liabilities 24 28 21 26
Purchases, issuances, and settlements        
Settlements (126) (91) (56) (136)
Net Assets (Liabilities) as of June 30 (102) 14 (102) 14
Total gains (losses) included in Net Income attributed to the change in unrealized gains (losses) related to assets and liabilities held at end of period (45) 63 (98) (27)
Total gains (losses) included in Regulatory liabilities attributed to the change in unrealized gains (losses) related to assets and liabilities held at end of period 0 30 0 30
Natural gas        
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]        
Net Assets (Liabilities) as of December 31 20 0 27 (18)
Transfers into Level 3 from Level 2 0 2 0 4
Transfers from Level 3 into Level 2     0 0
Total gains (losses)        
Included in earnings 19 (20) (53) (43)
Recorded in Regulatory liabilities 0 0 0 0
Purchases, issuances, and settlements        
Settlements (20) 9 45 48
Net Assets (Liabilities) as of June 30 19 (9) 19 (9)
Total gains (losses) included in Net Income attributed to the change in unrealized gains (losses) related to assets and liabilities held at end of period 9 (11) 8 (21)
Total gains (losses) included in Regulatory liabilities attributed to the change in unrealized gains (losses) related to assets and liabilities held at end of period 0 0 0 0
Electricity        
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]        
Net Assets (Liabilities) as of December 31 (93) (91) (19) 24
Transfers into Level 3 from Level 2 0 0 0
Transfers from Level 3 into Level 2     0 0
Total gains (losses)        
Included in earnings 45 182 (40) 146
Recorded in Regulatory liabilities 0 0 0 0
Purchases, issuances, and settlements        
Settlements (96) (99) (85) (178)
Net Assets (Liabilities) as of June 30 (144) (8) (144) (8)
Total gains (losses) included in Net Income attributed to the change in unrealized gains (losses) related to assets and liabilities held at end of period (54) 72 (106) (7)
Total gains (losses) included in Regulatory liabilities attributed to the change in unrealized gains (losses) related to assets and liabilities held at end of period 0 0 0 0
Other        
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]        
Net Assets (Liabilities) as of December 31 4 2 11 7
Transfers into Level 3 from Level 2 0 0 0 0
Transfers from Level 3 into Level 2     0 2
Total gains (losses)        
Included in earnings 5 2 7 2
Recorded in Regulatory liabilities 24 28 21 26
Purchases, issuances, and settlements        
Settlements (10) (1) (16) (6)
Net Assets (Liabilities) as of June 30 23 31 23 31
Total gains (losses) included in Net Income attributed to the change in unrealized gains (losses) related to assets and liabilities held at end of period 0 2 0 1
Total gains (losses) included in Regulatory liabilities attributed to the change in unrealized gains (losses) related to assets and liabilities held at end of period 0 30 0 30
DTE Electric        
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]        
Net Assets (Liabilities) as of December 31 4 3 11 9
Total gains (losses)        
Recorded in Regulatory liabilities 24 28 21 26
Purchases, issuances, and settlements        
Settlements (5) (1) (9) (5)
Net Assets (Liabilities) as of June 30 23 30 23 30
Total gains (losses) included in Regulatory liabilities attributed to the change in unrealized gains (losses) related to assets and liabilities held at end of period $ 0 $ 30 $ 0 $ 30