Income Taxes (Summary of Principal Components of Deferred Income Tax Assets and Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Deferred income tax assets
Net regulatory tax liability	$ 294	$ 307
Tax loss and credit carryforwards	139	258
Reserves and accruals	16	27
Total deferred income tax assets	449	592
Valuation allowance	(2)	(1)
Total deferred income tax assets, net of valuation allowance	447	591
Deferred income tax liabilities
Plant, property, and equipment	(2,833)	(2,682)
Employee benefits	(558)	(507)
Gas inventory	(24)	(38)
Securitized costs	(137)	(167)
Other	(147)	(122)
Total deferred income tax liabilities	(3,699)	(3,516)
Total net deferred income tax liabilities	(3,252)	(2,925)
Consumers Energy Company
Deferred income tax assets
Net regulatory tax liability	294	307
Tax loss and credit carryforwards	18	37
Reserves and accruals	13	24
Total deferred income tax assets, net of valuation allowance	325	368
Deferred income tax liabilities
Plant, property, and equipment	(2,808)	(2,658)
Employee benefits	(534)	(489)
Gas inventory	(24)	(38)
Securitized costs	(137)	(167)
Other	(23)	(69)
Total deferred income tax liabilities	(3,526)	(3,421)
Total net deferred income tax liabilities	$ (3,201)	$ (3,053)

The tax effect as of the balance sheet date of the amount of future tax deductions arising from tax carryforwards and the excesses of tax deductions over gross income in a year which cannot be used on the tax returns in the current year but can be carried forward to reduce taxable income or income taxes payable in a future year, for which there must be sufficient tax-basis income to utilize a portion or all of the carryforward amount to realize the deferred tax asset.

No definition available.