Effective income tax rate reconciliation federal and state.

No definition available.

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- Definition

Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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- Definition

Amount of deferred tax liability not recognized because of the exceptions to comprehensive recognition of deferred taxes related to bad debt reserve for tax purposes of a qualified lender.

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Amount of unrecognized tax benefits.

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Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Income Tax Contingency [Line Items]
Effective tax rate (as a percent)	20.70%	21.20%
Combined federal and state statutory tax rate (as a percent)	24.20%
Valuation allowance	$ 5		$ 5
First Niagara Bank, N.A.
Income Tax Contingency [Line Items]
Allocated bad debt deductions	92
Key Corp
Income Tax Contingency [Line Items]
Unrecognized tax benefits	3
Accrued Income And Other Assets
Income Tax Contingency [Line Items]
Net deferred tax assets	$ 1,200		$ 1,200