Income Taxes - Deferred Tax Assets (Liabilities) (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Losses on loans and other assets	$ 471,767	$ 309,523	$ 322,818
Operating lease liabilities	121,216	128,178
Retirement benefits	26,185	55,048	30,057
Postretirement and other employee benefits	28,004	24,023	23,563
Incentive and other compensation plans	18,984	26,861	24,796
Stock-based compensation	29,507	27,912	26,759
Unrealized losses			52,580
Losses on cash flow hedges			1,861
Other	66,763	69,863	43,880
Gross deferred tax assets	762,426	641,408	526,314
Right of use assets and other leasing transactions	(285,311)	(326,626)	(186,787)
Unrealized gains	(50,785)	(13,322)
Capitalized servicing rights	(50,235)	(56,649)	(54,894)
Depreciation and amortization	(95,684)	(66,925)	(61,881)
Interest on loans	(8,113)	(23,552)	(18,920)
Gains on cash flow hedges	(97,004)	(36,845)
Other	(62,581)	(40,472)	(30,211)
Gross deferred tax liabilities	(649,713)	(564,391)	(352,693)
Net deferred tax asset	$ 112,713	$ 77,017	$ 173,621

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 assets unrealized losses on investment securities.

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Deferred tax liabilities interest on loans.

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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 before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from hedging transactions.

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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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