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Percentage of eligible paycheck protection program loan.

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Represents the number of days past due for loans and leases to be considered nonperforming.

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Range of amount of impaired loans tested for impairment.

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Amount of expense related to loan loss not accounted for as debt securities, with evidence of deterioration of credit quality.

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Carrying amount as of the balance sheet date of all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance; includes real and personal property; equity interests in corporations, partnerships, and joint ventures; and beneficial interests in trusts.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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Allowance for Loan Losses - Additional Information (Detail) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2020 USD ($) Contract Loan	Dec. 31, 2021 USD ($) Contract SecurityLoan	Dec. 31, 2020 USD ($) SecurityLoan	Dec. 31, 2019 USD ($) Contract SecurityLoan
Accounts Notes And Loans Receivable [Line Items]
Period for calculating Loss migration rates of portfolio segments		3 years
Allowance for loan losses		$ 26,641	$ 25,028
Provision for loan losses		$ 830	$ 10,112	$ 1,035
Percentage of eligible paycheck protection program loan			100.00%
Number of days past due for loans to be considered as nonperforming		90 days
Reasonable period for nonperforming TDRs to be returned to performing status		6 months
Number of days reaching where loans are considered for nonaccrual status		90 days
Conditions where loans are considered for nonaccrual status		A loan may be returned to accruing status only if one of three conditions are met: the loan is well-secured and none of the principal and interest has been past due for a minimum of 90 days; the loan is a TDR and the borrower has made a minimum of six months payments; or the principal and interest payments are reasonably assured and a sustained period of performance has occurred, generally six months.
Gross interest income recorded on nonaccrual loans		$ 307	$ 536	571
Interest income on nonaccrual loans recognized on cash basis		716	477	$ 379
Loans modified as troubled debt restructuring		$ 0	$ 0
Defaulted loans \| SecurityLoan		0	0	0
Impaired loans		greater than $350
Number of loans modified \| Contract				1
Foreclosed assets		$ 0	$ 31
Allowance for loan losses recorded for acquired loans		0	0
Residential Mortgage [Member]
Accounts Notes And Loans Receivable [Line Items]
Residential mortgages in process of foreclosure			293	$ 741
Commercial and Agriculture [Member]
Accounts Notes And Loans Receivable [Line Items]
Provision for loan losses		(360)	604	500
Loans modified as troubled debt restructuring			431,300
Number of loans modified \| Contract	813
Commercial and Agriculture [Member] \| Second Modifications [Member]
Accounts Notes And Loans Receivable [Line Items]
Loans modified as troubled debt restructuring		$ 5,142
Number of loans modified \| Contract		7
Commercial and Agriculture [Member] \| Additional 90 Day Modifications [Member]
Accounts Notes And Loans Receivable [Line Items]
Loans modified as troubled debt restructuring	$ 124,400
Number of loans modified \| Loan	100
TDRs [Member]
Accounts Notes And Loans Receivable [Line Items]
Allowance for loan losses		$ 18	$ 35	$ 91