Loans and Allowance For Loan Losses - Summary of Financing Receivable and Related Impairment Methodology (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Loans and Leases Receivable Disclosure [Line Items]
Total loans	$ 968,945	$ 949,652
Commercial And Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total loans	416,308	389,746
Real Estate Construction & Land [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total loans	41,697	42,519
Real Estate HELOC [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total loans	995	982
Installment and Other [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total loans	13,180	13,476
Loans Receivable [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment	5,784	5,603
Loans collectively evaluated for impairment	963,161	944,049
Total loans	968,945	949,652
Loans Receivable [Member] \| Commercial And Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment	5,440	4,572
Loans collectively evaluated for impairment	410,868	385,174
Total loans	416,308	389,746
Loans Receivable [Member] \| Real Estate Construction & Land [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans collectively evaluated for impairment	41,697	42,519
Total loans	41,697	42,519
Loans Receivable [Member] \| Real Estate- Other [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment		687
Loans collectively evaluated for impairment	496,765	502,242
Total loans	496,765	502,929
Loans Receivable [Member] \| Real Estate HELOC [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans collectively evaluated for impairment	995	982
Total loans	995	982
Loans Receivable [Member] \| Installment and Other [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment	344	344
Loans collectively evaluated for impairment	12,836	13,132
Total loans	$ 13,180	$ 13,476

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

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=118936363&loc=SL6953423-111524

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

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Amount, before allowance and fees, of loans and leases receivable. 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=118952595&loc=d3e4428-111522

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