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Financing Receivable Impairment Minimum Performance Requirement Period

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Financing Receivable Impairment Modification Minimum Period

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Loans Held For Sale Average Life From Purchase To Sale

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Number Of Commitments To Lend Additional Funds For Troubled Debt Restructurings

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Amount, after allowance for credit loss, of accrued interest on financing receivable.

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Amount of writeoff of accrued interest on financing receivable recognized by reversing interest income.

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Amount of increase in allowance for credit loss on financing receivable purchased with credit deterioration.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of increase (decrease) in allowance for credit loss on financing receivable.

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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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Number of financing receivables that have been modified by troubled debt restructurings.

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Amount of financing receivable modified as troubled debt restructuring.

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Amount at purchase price of financing receivable purchased with credit deterioration.

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Amount of discount (premium) attributable to other factors on financing receivable purchased with credit deterioration.

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The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

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Loans and Leases Receivable and Allowance for Credit Losses - Additional Information (Detail) $ in Thousands				12 Months Ended
	Dec. 31, 2020 USD ($) Commitment	Sep. 30, 2020 USD ($)	Jan. 01, 2020 USD ($)	Dec. 31, 2020 USD ($) Loan Commitment	Dec. 31, 2019 USD ($) Commitment Loan	Dec. 31, 2018 USD ($) Loan Commitment
Financing Receivable, Troubled Debt Restructuring [Line Items]
Accrued interest	$ 76,600			$ 76,600	$ 34,800
Collateral-dependent loans	15,608,989			15,608,989	9,508,367
Interest income				$ 512,048	431,491	$ 373,234
Loans held for sale, average life from purchase to sale (days)				30 days
Accrued interest reversed				$ 1,300
Allowance for credit loss	144,176		$ 136,200	144,176	56,379	39,972
Allowance for credit loss, period increase				8,000
Troubled debt restructurings	$ 16,100			$ 16,100	$ 13,300	$ 19,200
Minimum performance requirement (months)				6 months
Contractual terms for loans (months)				6 months
Number of loans \| Loan				121	28	41
Commitments to lend additional funds to debtors \| Commitment	0			0	0	0
Number of TDR loans that defaulted on payments \| Loan				24	4	4
Amount of TDR loans that defaulted on payments				$ 614	$ 154	$ 92
Purchased-credit-impaired loans	$ 13,400	$ 13,400
Loans pledged as collateral	8,500,000			$ 8,500,000	4,600,000
Troubled Debt Restructurings
Financing Receivable, Troubled Debt Restructuring [Line Items]
Contractual terms for loans (months)				9 months
Small Business Administration (SBA), CARES Act, Paycheck Protection Program
Financing Receivable, Troubled Debt Restructuring [Line Items]
Interest income				$ 65,500
Accounting Standards Update 2016-13
Financing Receivable, Troubled Debt Restructuring [Line Items]
Initial allowance on loans purchased with credit deterioration			200
Financing receivable, purchased with credit deterioration, discount			$ 300
Residential real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Other real estate owned	100			100	200
Foreclosure loans	800			800	900
Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of TDR loans that defaulted on payments \| Loan						1
Amount of TDR loans that defaulted on payments						$ 1,500
Commercial real estate non-owner occupied
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amount deferred, CARES Act	202,100			202,100
Multi-family
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit loss	12,620			12,620	$ 6,157	$ 11,462
Consumer loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amount deferred, CARES Act	16,400			$ 16,400
Principal Forgiveness
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans \| Loan				0	0	0
Commercial Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans held for sale, fair value	17,300			$ 17,300
Commercial Real Estate \| Commercial and industrial \| Collateral-dependent loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Collateral-dependent loans	59,500			59,500
Government-Guaranteed Collateral \| Small Business Administration (SBA), CARES Act, Paycheck Protection Program
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans pledged as collateral	$ 4,600,000			$ 4,600,000