Income Taxes - Deferred Tax Assets (Liabilities) (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Losses on loans and other assets	$ 395,784	$ 471,767	$ 309,523
Operating lease liabilities	110,023	121,216	128,178
Retirement benefits		26,185	55,048
Postretirement and other employee benefits	31,760	28,004	24,023
Incentive and other compensation plans	24,713	18,984	26,861
Stock-based compensation	32,675	29,507	27,912
Other	52,351	66,763	69,863
Gross deferred tax assets	647,306	762,426	641,408
Right of use assets and other leasing transactions	(249,209)	(285,311)	(326,626)
Unrealized gains	(27,066)	(50,785)	(13,322)
Retirement benefits	(45,402)
Capitalized servicing rights	(53,219)	(50,235)	(56,649)
Depreciation and amortization	(93,103)	(95,684)	(66,925)
Interest on loans	(6,690)	(8,113)	(23,552)
Gains on cash flow hedges	(22,820)	(97,004)	(36,845)
Other	(88,053)	(62,581)	(40,472)
Gross deferred tax liabilities	(585,562)	(649,713)	(564,391)
Net deferred tax asset	$ 61,744	$ 112,713	$ 77,017

Amount of deferred tax asset attributable to taxable temporary differences from losses on loans and other assets.

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Deferred tax assets operating lease liabilities.

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Amount of deferred tax asset attributable to taxable temporary differences from deferred expense compensation and benefits postretirement and other employee benefits.

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Deferred tax liabilities interest on loans.

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Deferred tax liabilities retirement benefits.

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Amount of deferred tax liability attributable to taxable temporary differences from unrealized gains on investment securities.

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Deferred tax liability depreciation and amortization

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Deferred tax liability gains on cash flow hedges.

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences from employee benefits, classified as other.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from employee compensation.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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Amount of deferred tax liability attributable to taxable temporary differences from leasing arrangements.

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Amount of deferred tax liability attributable to taxable temporary differences from mortgage servicing rights.

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Amount of deferred tax liability attributable to taxable temporary differences classified as other.

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