Federal, State, and Local Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Deferred Tax Assets:
Allowance for credit losses on loans and leases	$ 273	$ 314
Acquisition accounting and fair value adjustments on securities (including OTTI)	133	177
Right of use liability	113	121
Non-accrual interest	70	11
Compensation and related benefit obligations	47	54
Other	29	27
Unrealized gains and amortization of mortgage servicing rights	0	26
Accrued expenses	15	16
Net operating loss carryforwards	8	12
Gross deferred tax assets	688	758
Valuation allowance	(4)	(4)
Net deferred tax asset after valuation allowance	684	754
Deferred Tax Liabilities:
Leases	(281)	(315)
Fair value adjustments on loans	(161)	(198)
Right of use asset	(101)	(109)
Amortizable intangibles	(72)	(95)
Prepaid pension cost	(44)	(37)
Premises and equipment	(38)	(29)
Other	(22)	(14)
Acquisition accounting and fair value adjustments on debt	(7)	(8)
Gross deferred tax liabilities	(726)	(805)
Net deferred tax liability	$ (42)	$ (51)

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from allowance for credit loss on financing receivable.

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