v3.26.1
Significant Accounting Policies (Roll-Forward of Activity for Financing Receivables Credit Loss Reserves) (Details) - USD ($)
$ in Millions
 6 Months Ended 12 Months Ended
Jun. 30, 2026
Dec. 31, 2025
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]    
Beginning reserve balance $ 62 $ 72
Current period provision 58 69
Write-offs charged against allowance (56) (116)
Recoveries of amounts previously written off 19 37
Ending reserve balance 83 62
DTE Electric    
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]    
Beginning reserve balance 41 46
Current period provision 30 44
Write-offs charged against allowance (38) (74)
Recoveries of amounts previously written off 13 25
Ending reserve balance 46 41
Trade accounts receivable    
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]    
Beginning reserve balance 59 69
Current period provision 58 69
Write-offs charged against allowance (56) (116)
Recoveries of amounts previously written off 19 37
Ending reserve balance 80 59
Other receivables    
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]    
Beginning reserve balance 3 3
Current period provision 0 0
Write-offs charged against allowance 0 0
Recoveries of amounts previously written off 0 0
Ending reserve balance $ 3 $ 3