Fair Value (Reconciliation of Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - Recurring - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of beginning of period	$ 14	$ 38	$ 13	$ 75
Transfers into Level 3 from Level 2	0	2	2	2
Transfers from Level 3 into Level 2	(4)	0	2	0
Total gains (losses)
Included in earnings	158	112	260	208
Recorded in Regulatory liabilities	(6)	2	20	29
Purchases, issuances, and settlements
Settlements	(119)	(111)	(254)	(271)
Net Assets (Liabilities) as of end of period	43	43	43	43
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	56	59	16	90
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	(5)	2	18	21
DTE Electric
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of beginning of period	30	28	9	7
Total gains (losses)
Recorded in Regulatory liabilities	(6)	2	20	29
Purchases, issuances, and settlements
Settlements	(6)	(9)	(11)	(15)
Net Assets (Liabilities) as of end of period	18	21	18	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	(5)	2	18	21
Natural gas
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Net Assets (Liabilities) as of beginning of period	(9)	3	(18)	22
Transfers into Level 3 from Level 2	0	0	2	1
Transfers from Level 3 into Level 2	(4)	0	0	0
Total gains (losses)
Included in earnings	28	7	(17)	13
Recorded in Regulatory liabilities	0	0	0	0
Purchases, issuances, and settlements
Settlements	4	(15)	52	(41)
Net Assets (Liabilities) as of end of period	19	(5)	19	(5)
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	37	(6)	13	(25)
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 beginning of period	(8)	9	24	47
Transfers into Level 3 from Level 2	0	2	0	1
Transfers from Level 3 into Level 2	0	0	0	0
Total gains (losses)
Included in earnings	130	105	275	196
Recorded in Regulatory liabilities	0	0	0	0
Purchases, issuances, and settlements
Settlements	(117)	(87)	(294)	(215)
Net Assets (Liabilities) as of end of period	5	29	5	29
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	19	75	2	156
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 beginning of period	31	26	7	6
Transfers into Level 3 from Level 2	0	0	0	0
Transfers from Level 3 into Level 2	0	0	2	0
Total gains (losses)
Included in earnings	0	0	2	(1)
Recorded in Regulatory liabilities	(6)	2	20	29
Purchases, issuances, and settlements
Settlements	(6)	(9)	(12)	(15)
Net Assets (Liabilities) as of end of period	19	19	19	19
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	(10)	1	(41)
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	$ (5)	$ 2	$ 18	$ 21