Leases (Other Information Related to Leases) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Cash paid for amounts included in the measurement of these liabilities:
Operating cash flows for finance leases	$ 5	$ 9	$ 9
Operating cash flows for operating leases	27	19	19
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	95	75	61
Finance leases	$ 0	$ 16	$ 5
Weighted Average Remaining Lease Term (Years)
Operating leases	24 years 6 months	23 years 3 months 18 days	18 years 8 months 12 days
Finance leases	6 years 7 months 6 days	7 years 4 months 24 days	8 years 10 months 24 days
Weighted Average Discount Rate
Operating leases	5.10%	4.80%	4.40%
Finance leases	4.50%	4.60%	4.00%
DTE Electric
Cash paid for amounts included in the measurement of these liabilities:
Operating cash flows for finance leases	$ 3	$ 7	$ 7
Operating cash flows for operating leases	21	15	15
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	86	74	61
Finance leases	$ 0	$ 14	$ 5
Weighted Average Remaining Lease Term (Years)
Operating leases	26 years 3 months 18 days	24 years 9 months 18 days	19 years 9 months 18 days
Finance leases	3 years	4 years	4 years 6 months
Weighted Average Discount Rate
Operating leases	5.20%	4.90%	4.50%
Finance leases	5.80%	5.80%	5.40%