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Financing receivable modifications payment deferral additional number of days.

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Financing receivable modifications payment deferral number of days .

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Financing receivables apply for extension.

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Number of loan applications received.

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Payment protection loan applications received amount.

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Percentage of processed application under PPP loan.

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Value of financing receivables apply for loan forgiveness.

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Value of financing receivables apply for loan forgiveness in process.

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Amount of amortization expense attributable to debt issuance costs.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Decrease for amounts of indebtedness forgiven by the holder of the debt instrument.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Income from mortgage banking activities (fees and commissions) and servicing real estate mortgages, credit cards, and other financial assets held by others net of any related impairment of capitalized service costs. Also includes any premiums received in lieu of regular servicing fees on such loans only as earned over the life of the loans.

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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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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The net amount of operating interest income (expense).

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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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash inflow from repayments of the balance excluding interest (principal) on loans receivable and leases held for investment purposes.

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Amount of expense related to estimated loss from loan and lease transactions.

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Business Impact Of Covid-19 - Additional Information (Detail)			3 Months Ended		9 Months Ended		12 Months Ended
	Jun. 05, 2021	Jun. 05, 2020	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) Loans	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) Loans	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)
Financing receivable, modifications, number of contracts \| Loans					0		0
Financing receivable, troubled debt restructuring			$ 0		$ 0		$ 0
Financing receivable modifications payment deferral number of days					10 months
Number of loan applications received \| Loans					333
Payment protection loan applications received amount			362,000,000.0		$ 362,000,000.0
Goodwill, Impairment					$ 0
Percentage of processed application under PPP loan					100.00%
Loan funded under PPP loan			97,400,000		$ 97,400,000
Interest Income (Expense), Net			13,841,000	$ 11,188,000	40,763,000	$ 32,154,000
Provision for Loan and Lease Losses			300,000	850,000	(500,000)	4,180,000
Loans and Leases Receivable, Allowance			$ 13,571,000	13,385,000	$ 13,571,000	$ 13,385,000	14,111,000	$ 13,240,000	$ 12,524,000	$ 11,075,000
SBA Payment Protection Program [Member]
Debt Instrument, Term	60 months	24 months
Debt Instrument, Fixed Interest Rate			1.00%		1.00%
Number of loan applications received \| Loans					730
Value of financing receivables apply for loan forgiveness			$ 390		$ 390
Value of financing receivables apply for loan forgiveness in process			350,100,000		350,100,000
Proceeds from repayments of long term loans advanced					5,400,000
PPP Loans [Member]
Loan funded under PPP loan			6,500,000		6,500,000
Interest Income (Expense), Net			348,000		1,500,000
Debt instrument, Decrease, Forgiveness					38,300,000
Long-term debt			90,900,000		$ 90,900,000
SBA Payment Protection Program Relaunched [Member]
Percentage of processed application under PPP loan					100.00%
Loan funded under PPP loan			129,200,000		$ 129,200,000
COVID-19 [Member] \| PPP Loans [Member]
Fees received					4,400,000		9,100,000
Amortization of loan			1,900,000	$ 3,000,000.0	6,300,000
Interest Income (Expense), Net			1,900,000		6,500,000
Provision for Loan and Lease Losses			300,000
Loans and Leases Receivable, Allowance			500,000		$ 500,000
COVID-19 [Member] \| Payment Deferral [Member]
Financing receivable, modifications, number of contracts \| Loans					383
Financing receivable, troubled debt restructuring							323,900,000
Financing receivable modifications aggregate monthly principal and interest payments							$ 3,700,000
Financing receivable modifications payment deferral number of days					90 days
Financing receivable modifications, payment deferral, additional number of days					90 days
Financing receivables apply for extension			$ 6,700,000		$ 6,700,000