Significant Accounting Policies (Effective Income Tax Rate Reconciliation) (Details)	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Schedule of Income Taxes [Line Items]
Statutory federal income tax rate	21.00%	21.00%
Increase (decrease) due to:
State and local income taxes, net of federal benefit	6.60%	4.20%
Investment tax credits	(35.40%)	(13.10%)
Production tax credits	(21.30%)	(10.50%)
TCJA regulatory liability amortization	(7.40%)	(4.50%)
AFUDC equity	(3.90%)	(1.50%)
Nondeductible EES Coke penalty(a)	9.80%	0.00%
Other	(0.30%)	0.20%
Effective Tax Rate	(30.90%)	(4.20%)
DTE Electric
Schedule of Income Taxes [Line Items]
Statutory federal income tax rate	21.00%	21.00%
Increase (decrease) due to:
State and local income taxes, net of federal benefit	5.60%	5.70%
Investment tax credits	(21.50%)	(16.60%)
Production tax credits	(6.40%)	(7.00%)
TCJA regulatory liability amortization	(4.20%)	(4.60%)
AFUDC equity	(2.60%)	(1.80%)
Other	(0.40%)	0.40%
Effective Tax Rate	(8.50%)	(2.90%)