Loans and Allowance for Credit Losses - Additional Information (Details)	12 Months Ended
Dec. 31, 2021 USD ($) Loan	Dec. 31, 2020 USD ($) Loan	May 31, 2021 USD ($)
Financing Receivable Modifications [Line Items]
Commitments to lend additional funds to borrowers whose loans were on non-accrual status	$ 0	$ 0
Number of loans modified during the period \| Loan	0	0
Number of loans determined to be troubled debt restructurings \| Loan	4	4
Number of TDRs defaulted during the period \| Loan	0	1
Allowance for credit losses	$ 35,880,000	$ 37,020,000
Loans in deferral	4,700,000
PPP Loans
Financing Receivable Modifications [Line Items]
Maximum loan eligibility for first time borrowers			$ 2,000,000.0
Troubled Debt Restructurings
Financing Receivable Modifications [Line Items]
Troubled debt restructuring carrying value	758,000	811,000
Allowance for credit losses	$ 85,000	$ 90,000

Financing receivable number of loans determined to be troubled debt restructurings.

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- Definition

Loans and leases receivable nonaccrual status commitment to lend.

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Maximum loan eligibility for first time borrowers.

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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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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 deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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