Gain (loss) on sale of Paycheck Protection Program loans.

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- Definition

Loans and lease receivable contractual term.

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No definition available.

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Loans and lease receivable prior period.

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Loans and lease receivable subsequent period.

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No definition available.

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Loans and lease receivables unamortized fees net of deferred costs and the sale discount.

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No definition available.

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Loans and leases receivable number of loans.

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No definition available.

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Loans and leases receivable originated.

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No definition available.

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Loans and leases receivable payrolls and other operating expenses.

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No definition available.

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Loans and leases receivable recognized interest income.

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No definition available.

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- Definition

Loans and leases receivable unamortized processing fee.

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No definition available.

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- Definition

Loans and leases receivables number of loans sold.

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No definition available.

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- Definition

Nonrefundable fees and other costs deferred and amortized as component of loan yield over expected life of loans.

+ References

No definition available.

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Number of loan deferrals.

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No definition available.

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- Definition

Percentage of loan earned processing fee one rate.

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No definition available.

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Percentage of loan earned processing fee three rate.

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No definition available.

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Percentage of loan earned processing fee two rate.

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No definition available.

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- Definition

Percentage of loans receivable interest rate.

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No definition available.

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- Definition

Processing fee for loans balance.

+ References

No definition available.

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- Definition

Processing fee for loans more than loan balance.

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No definition available.

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- Definition

Processing fee for loans more than loan balance percentage.

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No definition available.

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- Definition

Processing fee for loans not more than loan balance.

+ References

No definition available.

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Processing fee for loans not more than loan balance percentage.

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No definition available.

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans and leases that were sold during the reporting period. This element refers to the gain (loss) and not to the cash proceeds of the sales. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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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

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount of undisbursed portion of the loan receivable balance (loans in process). Excludes loans and leases covered under loss sharing agreements.

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No definition available.

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- Definition

Amount, before valuation allowance, of financing receivable classified as held-for-sale.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The carrying amount, as of the date of the latest financial statement presented, of loans receivable which are owned but transferred to serve as collateral for the payment of FHLB debt obligations, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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- Definition

The cash inflow resulting from the sale of loans classified as held-for-sale, including proceeds from loans sold through mortgage securitization.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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Loans and Allowance for Loan Losses - Additional Information (Detail)		1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Jun. 28, 2021 USD ($) Loan	Apr. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) Loan	Jun. 30, 2021 USD ($)	Sep. 30, 2021 USD ($) Loan	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) Loan	Jan. 31, 2021 USD ($) Loan
Loans and Leases Receivable Disclosure [Line Items]
Gross loans			$ 1,800,541,000		$ 1,800,541,000		$ 1,025,687,000
Proceeds from sale of loans held for sale					965,119,000	$ 652,765,000
Gain on sale of Paycheck Protection Program loans					(24,315,000)
Nonperforming trouble debt restructuring					235,000		142,000
Substandard [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans			33,519,000		33,519,000		16,714,000
Troubled debt restructuring			500,000		500,000
Payment Deferral [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans			$ 4,700,000		$ 4,700,000		$ 110,600,000
Number of loan deferrals \| Loan			16		16		550
Payment Deferral [Member] \| Bay Banks [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans								$ 160,000,000.0
Number of loan deferrals \| Loan								400
PPP 1 [Member]
Loans and Leases Receivable Disclosure [Line Items]
Payrolls and other operating expenses		$ 650,000,000,000
Loans and lease receivable prior period		2 years
Loans and lease receivable subsequent period		5 years
Percentage of Loans receivable interest rate		1.00%
Percentage of loan earned processing fee one rate		1.00%
Percentage of loan earned processing fee two rate		3.00%
Percentage of loan earned processing fee three rate		5.00%
Loans and leases receivable originated							$ 363,400,000
Gross loans			$ 32,600,000		$ 32,600,000
Nonrefundable fees and other costs deferred and amortized as component of loan yield over expected life of loans					1 year 6 months
Loans and leases receivable of processing fees, net of agent fees							11,500,000
Loans and leases receivable unamortized fee			0		$ 0
Loans and leases receivable recognized interest income			$ 228,000		$ 4,800,000
PPP 2 [Member]
Loans and Leases Receivable Disclosure [Line Items]
Percentage of Loans receivable interest rate			1.00%		1.00%
Gross loans	$ 712,600,000		$ 730,000,000		$ 730,000,000
Number of loans \| Loan					20,000
Loans and lease receivable contractual term					5 years
Number of loans sold \| Loan	19,500
Proceeds from sale of loans held for sale	$ 705,900,000
Gain on sale of Loans	24,300,000
Unamortized fees net of deferred costs and the sale discount	$ 30,900,000
Financing Receivable, Held-for-Sale			14,700,000		$ 14,700,000
Unamortized fees, net of deferred cost			676,000		676,000
Loans and leases receivable of processing fees, net of agent fees			40,800,000		40,800,000
Loans and leases receivable recognized interest income			484,000		$ 12,100,000
Gain on sale of Paycheck Protection Program loans				$ (30,900)
PPP 2 [Member] \| Maximum [Member]
Loans and Leases Receivable Disclosure [Line Items]
Nonrefundable fees and other costs deferred and amortized as component of loan yield over expected life of loans					3 years
PPP 2 [Member] \| Scenario One [Member]
Loans and Leases Receivable Disclosure [Line Items]
Processing fee for loans not more than loan balance			$ 50,000		$ 50,000
Processing fee for loans not more than loan balance percentage			50.00%		50.00%
Processing fee for loans balance			$ 2,500		$ 2,500
PPP 2 [Member] \| Scenario Two [Member]
Loans and Leases Receivable Disclosure [Line Items]
Processing fee for loans not more than loan balance			$ 350,000		$ 350,000
Processing fee for loans not more than loan balance percentage			5.00%		5.00%
Processing fee for loans more than loan balance			$ 50,000		$ 50,000
PPP 2 [Member] \| Scenario Three [Member]
Loans and Leases Receivable Disclosure [Line Items]
Processing fee for loans more than loan balance			$ 350,000		$ 350,000
Processing fee for loans more than loan balance percentage			3.00%		3.00%
Commercial and Residential Mortgages [Member] \| FHLB [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans pledged			$ 517,600,000		$ 517,600,000		213,300,000
Pay Check Protection Loans [Member] \| Paycheck Protection Plan Liquidity Facility Advances [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans pledged			33,900,000		33,900,000		281,600,000
Paycheck Protection Program [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans			$ 47,325,000		$ 47,325,000		$ 292,068,000