Additional committed impaired loans.

No definition available.

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- Definition

Financing receivable, deferral amount.

+ References

No definition available.

+ Details

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- Definition

Participation loans transferred.

+ References

No definition available.

+ Details

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- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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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
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
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-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953682-111524

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- Definition

Amount of financing receivable 90 days or more past due and still accruing.

+ References

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-Name Accounting Standards Codification
-Topic 326
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- Definition

Threshold period for when financing receivable is considered past due, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes threshold period past due to write off as uncollectible.

+ References

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919253-210447

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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.

+ Details

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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.

+ References

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

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-Publisher FASB
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Loans - Additional Information (Detail) - USD ($)	3 Months Ended		12 Months Ended
Loans - Additional Information (Detail) - USD ($)	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Loans and Leases Receivable Disclosure [Line Items]
Loans 90 days or more past due and accruing interest	$ 0		$ 0
Internal risk ratings of loans	329,994,000		331,598,000
Additional committed impared loans	0		0
Loans modified as troubled debt restructurings	0		0
Troubled debt restructurings within past twelve months for which there was a default	0	$ 0
Loans and leases receivable, net amount	327,565,000		329,073,000
Covid Nineteen [Member] \| Payment Deferral [Member]
Loans and Leases Receivable Disclosure [Line Items]
Financing recievable threshold past due				30 days
Loans and leases receivable, net amount	14,100,000
Financing receivable deferral amount	354,000
Doubtful [Member]
Loans and Leases Receivable Disclosure [Line Items]
Internal risk ratings of loans	0		0
Other Financial Institutions [Member]
Loans and Leases Receivable Disclosure [Line Items]
Participation loans transferred	$ 31,800,000		$ 29,600,000