Income Taxes (Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Components of Deferred Tax Assets and Liabilities [Abstract]
Property, plant, and equipment	$ (3,952)	$ (3,695)
Regulatory assets and liabilities	(1,412)	(1,272)
Tax credit carryforwards	1,619	1,604
Pension and benefits	3	55
Federal net operating loss carryforward	180	190
State and local net operating loss carryforwards	51	68
Investments in equity method investees	(25)	(28)
Other	182	145
Deferred tax assets (liabilities)	(3,354)	(2,933)
Less: Valuation allowance	(46)	(25)
Long-term deferred income tax liabilities	(3,400)	(2,958)
Deferred income tax assets	2,575	2,508
Deferred income tax liabilities	(5,975)	(5,466)
DTE Electric
Components of Deferred Tax Assets and Liabilities [Abstract]
Property, plant, and equipment	(2,947)	(2,788)
Regulatory assets and liabilities	(1,636)	(1,492)
Tax credit carryforwards	512	583
Pension and benefits	2	62
Federal net operating loss carryforward	24	30
State and local net operating loss carryforwards	27	42
Investments in equity method investees	(1)	(1)
Other	207	176
Deferred tax assets (liabilities)	(3,812)	(3,388)
Less: Valuation allowance	0	(5)
Long-term deferred income tax liabilities	(3,812)	(3,393)
Deferred income tax assets	1,188	1,209
Deferred income tax liabilities	$ (5,000)	$ (4,602)