Nonperforming loans charged off past due period.

No definition available.

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- Definition

Number of Restructured Loans

+ References

No definition available.

+ Details

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- Definition

Maximum duration past due for restructured loans to be considered performing.

+ References

No definition available.

+ Details

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- Definition

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

+ References

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Period Type:	instant

- 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.

+ References

No definition available.

+ Details

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- Definition

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

+ References

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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- Definition

Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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- Definition

Amount of interest income, recognized on cash basis, on financing receivables, for which there is no related allowance for credit losses and are recognized as impaired.

+ References

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- Definition

Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

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- Definition

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

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Purchased Loans - Additional Information (Details)	12 Months Ended
Purchased Loans - Additional Information (Details)	Dec. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($) loan	Dec. 31, 2018 USD ($) loan	Dec. 31, 2017 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Outstanding balance of restructured loans	$ 10,757,503,000	$ 9,637,476,000
Restructured loans discontinued past due period	90 days
Allowance for loan losses attributable to restructured loans	$ 176,144,000	$ 52,162,000	$ 49,026,000	$ 46,211,000
Purchased
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonperforming loans charged off past due period	90 days
Number of restructured loans \| loan	1	2
Restructured loans discontinued past due period	90 days	90 days
Modifications, recorded investment	$ 8,687,000	$ 7,275,000	7,495,000
Modifications, subsequent default, recorded investment	74,000	101,000	$ 5,000
Remaining availability under commitments to lend additional funds on restructured loans	$ 370,000	$ 6,000
Number of loans on deferral \| loan	13	5	5
Deferral amount	$ 5,262,000	$ 2,931,000	$ 712,000
Average recorded investment in impaired loans		14,151,000	9,396,000
Interest income recognized on credit-deteriorated loans		80,000
Interest income, impaired		172,000	$ 194,000
Purchased \| Payment Deferral \| Loan Deferral Program, CARES Act
Financing Receivable, Allowance for Credit Loss [Line Items]
Number of loans on deferral \| loan	284
Deferral amount	$ 33,000,000
Purchased \| Nonaccruing Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Outstanding balance of restructured loans	74,000	106,000
Purchased \| Restructured Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Outstanding balance of restructured loans	12,788,000	1,667,000
Allowance for loan losses attributable to restructured loans	$ 612,000	$ 17,000