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, 2022	Dec. 31, 2021
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 92	$ 104
Current period provision	32	54
Write-offs charged against allowance	(45)	(127)
Recoveries of amounts previously written off	23	61
Ending balance	102	92
DTE Electric
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	54	57
Current period provision	15	36
Write-offs charged against allowance	(30)	(77)
Recoveries of amounts previously written off	14	38
Ending balance	53	54
Trade accounts receivable
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	89	101
Current period provision	32	53
Write-offs charged against allowance	(45)	(126)
Recoveries of amounts previously written off	23	61
Ending balance	99	89
Other receivables
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	3	3
Current period provision	0	1
Write-offs charged against allowance	0	(1)
Recoveries of amounts previously written off	0	0
Ending balance	$ 3	$ 3