Additional funds available to be advanced in connection with impaired loans.

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Delinquent period for charging down consumer loans

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Delinquent period for charging down or allocated commercial and agricultural credits.

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- Definition

Financing receivables impaired number of troubled debt restructuring write down.

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Litigation and any deficiency charged off period.

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Maximum time for reevaluation.

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Re evaluation period for real estate.

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- Definition

Unsecured consumer loans credit card credits and overdraft.

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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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No definition available.

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Remaining amortization period for discount on the liability component of convertible debt which may be settled in cash upon conversion, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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 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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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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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

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Loans (Impaired Loans) - Additional Information (Detail)		1 Months Ended			12 Months Ended
	Jul. 30, 2021	Apr. 30, 2022 Loan	Jun. 30, 2021 Loan	Mar. 31, 2021 Loan	Dec. 31, 2022 USD ($) Loan Contract	Dec. 31, 2021 USD ($) Loan	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Additional funds available to be advanced in connection with impaired loans					$ 0
Impaired loans classified as troubled debt restructured					$ 3,600,000	$ 7,600,000
Number of contracts modified \| Loan					3	3
TDR impaired loans paid off \| Loan		2	2	3	1
Term of loan	5 years					3 years
Loan amortization period						10 years
Allowance for loan losses					$ 20,313,000	$ 16,242,000	$ 13,672,000	$ 7,228,000
TDR loans, subsequently defaulted during the period					0	0
Maximum time for re-evaluation (in months)					12 months
Re-evaluation period for real estate					2 years
Unsecured consumer loans, credit card credits and overdraft lines of credit reach					90 days
Delinquent period for charging down consumer loans					90 days
Litigation and any deficiency charged off period					150 days
Delinquent period for charging down/allocated commercial and agricultural credits					120 days
Foreclosed residential real estate property						$ 159,000
Consumer Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of contracts modified \| Contract					1
Foreclosed residential real estate property					$ 0	159,000
Residential real estate properties foreclosure proceedings						255,000
Specific Allocation on Principal Balance [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses						$ 825,000
Principal Forgiveness [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of contracts modified \| Contract					0
Sale Of Property
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of contracts modified \| Loan						1
Payment Changes from Monthly Payment to Principal and Interest at Maturity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of contracts modified \| Loan						1
Allowance for loan losses					$ 837,000	$ 313,000