Loans Receivable - Schedule of Investment in Loans Receivable by Loan Class (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Schedule Of Financial Receivables [Line Items]
Loan Receivable Ending Balance	$ 1,301,699	$ 1,042,146
Loan Receivable Ending Balance: Individually Evaluated for Impairment	2,020	1,482
Loan Receivable Ending Balance: Collectively Evaluated for Impairment	1,299,679	1,040,664
Residential Real Estate [Member]
Schedule Of Financial Receivables [Line Items]
Loan Receivable Ending Balance	157,518	150,848
Loan Receivable Ending Balance: Individually Evaluated for Impairment	299	1,482
Loan Receivable Ending Balance: Collectively Evaluated for Impairment	157,219	149,366
Commercial Real Estate [Member]
Schedule Of Financial Receivables [Line Items]
Loan Receivable Ending Balance	505,201	421,870
Loan Receivable Ending Balance: Individually Evaluated for Impairment	1,097
Loan Receivable Ending Balance: Collectively Evaluated for Impairment	504,104	421,870
Real Estate Construction Land And Land Development [Member]
Schedule Of Financial Receivables [Line Items]
Loan Receivable Ending Balance	325,516	272,620
Loan Receivable Ending Balance: Collectively Evaluated for Impairment	325,516	272,620
Commercial and Industrial Sector [Member]
Schedule Of Financial Receivables [Line Items]
Loan Receivable Ending Balance	261,959	121,225
Loan Receivable Ending Balance: Individually Evaluated for Impairment	517
Loan Receivable Ending Balance: Collectively Evaluated for Impairment	261,442	121,225
Consumer Loan [Member]
Schedule Of Financial Receivables [Line Items]
Loan Receivable Ending Balance	51,505	75,583
Loan Receivable Ending Balance: Individually Evaluated for Impairment	107
Loan Receivable Ending Balance: Collectively Evaluated for Impairment	$ 51,398	$ 75,583

Schedule Of Financial Receivables [Line Items]

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

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