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Commitments and Contingent Liabilities - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended	12 Months Ended
	Jun. 30, 2018	Jun. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Commitments And Contingencies Liabilities [Line Items]
Rental expenses			$ 5,800,000	$ 5,500,000	$ 4,600,000
Sublease income			752,000	723,000	702,000
Minimum rental to be received in future on subleases			$ 1,200,000
Sublease contract maturity year			2025
Data processing			$ 13,733,000	$ 18,242,000	$ 9,539,000
Fixed rate loan commitments maturity year			2043
Variable rate loan commitments maturity year			2048
Maximum
Commitments And Contingencies Liabilities [Line Items]
Commitments to make loans period			90 days
Loan commitments fixed interest rate			19.50%
Loan commitments variable interest rate			10.00%
Minimum
Commitments And Contingencies Liabilities [Line Items]
Loan commitments fixed interest rate			2.50%
Loan commitments variable interest rate			2.75%
Contract termination
Commitments And Contingencies Liabilities [Line Items]
Data processing	$ 8,100,000	$ 8,100,000
Remaining data processing cost balance			$ 0

X

- Definition

Commitments and contingencies liabilities.

+ References

No definition available.

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- Definition

Fixed rate loan commitment period.

+ References

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- Definition

Loan commitments bearing fixed interest rate, percentage.

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Loan commitments bearing variable interest rate, percentage.

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Remaining information technology and data processing.

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- Definition

Sublease contract expiration period.

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- Definition

The amount of expenses incurred in the period for information technology and data processing products and services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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- Definition

Contractually required future rental payments receivable on noncancelable subleasing arrangements.

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Amount of sublease income excluding finance and operating lease expense.

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