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

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- Definition

Delinquent period for charging down commercial and agricultural credits.

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No definition available.

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- Definition

Delinquent period for charging down consumer loans

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No definition available.

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- Definition

Financing receivables impaired number of troubled debt restructuring charged off.

+ References

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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No definition available.

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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.

+ References

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.

+ References

No definition available.

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- Definition

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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- 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.

+ References

No definition available.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

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- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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- Definition

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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- Definition

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		3 Months Ended		9 Months Ended
	Jul. 30, 2021	Jun. 30, 2021 Loan	May 31, 2020 Loan	Sep. 30, 2021 USD ($) Loan	Sep. 30, 2020 USD ($) Loan	Sep. 30, 2021 USD ($) Contract Loan	Sep. 30, 2020 USD ($) Contract 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		$ 0
Impaired loans classified as troubled debt restructured				$ 6,000,000.0	$ 6,400,000	$ 6,000,000.0	$ 6,400,000	$ 6,500,000
Number of contracts modified \| Loan				1	1	2	6
TDR impaired loans paid off \| Loan		2	1
Term of loan	5 years					3 years
Loan amortization period						10 years
Allowance for loan losses				$ 15,698,000		$ 15,698,000		13,672,000	$ 7,228,000
TDR loans, subsequently defaulted during the period				0	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 commercial and agricultural credits						120 days
Foreclosed residential real estate property				$ 167,000		$ 167,000		71,000
Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Litigation and any deficiency charged off period						150 days
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impaired loans classified as troubled debt restructured				86,000	$ 481,000	$ 86,000	$ 481,000
Number of contracts modified \| Contract						1	2
TDR impaired loans paid off \| Loan						1
Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impaired loans classified as troubled debt restructured				480,000		$ 480,000
TDR impaired loans paid off \| Loan						1
Allowance for loan losses				0		$ 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				167,000	71,000	167,000	$ 71,000	71,000
Residential real estate properties foreclosure proceedings				129,000	$ 849,000	$ 129,000	$ 849,000	$ 910,000
Principal Forgiveness [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of contracts modified \| Contract						0
Specific Allocation on Principal Balance [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses				$ 1,000,000.0		$ 1,000,000.0