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

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- Definition

Delinquent period for charging down consumer loans

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No definition available.

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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 charged off.

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No definition available.

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- Definition

Financing receivables impaired number of troubled debt restructuring write down.

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No definition available.

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- Definition

Litigation and any deficiency charged off period.

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- Definition

Maximum time for reevaluation.

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- Definition

Re evaluation period for real estate.

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No definition available.

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- Definition

Unsecured consumer loans credit card credits and overdraft.

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No definition available.

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- 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.

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No definition available.

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- Definition

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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No definition available.

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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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Reflects the amount of the write-down related to a troubled debt restructuring.

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- Definition

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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- Definition

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)		3 Months Ended
	Jul. 30, 2021	Mar. 31, 2022 USD ($) Loan Contract	Mar. 31, 2021 USD ($) Loan	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
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		$ 7,300,000	$ 5,800,000	$ 7,600,000
Number of contracts modified \| Loan			0
TDR impaired loans paid off \| Loan		0	0
Term of loan	5 years
Allowance for loan losses		$ 16,771,000		16,242,000	$ 13,672,000
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
Delinquent period for charging down/allocated commercial and agricultural credits		120 days
Foreclosed residential real estate property				159,000
Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Litigation and any deficiency charged off period		150 days
Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses		$ 0
TDR impaired loans charged off \| Loan			3
TDR impaired loans charged off amount			$ 809,000
Consumer Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Foreclosed residential real estate property		0	148,000	159,000
Residential real estate properties foreclosure proceedings		$ 291,000	$ 796,000	$ 255,000
Principal Forgiveness [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of contracts modified \| Contract		0