Loans and Allowance For Loan Losses - Summary of Financing Receivable and Related Impairment Methodology (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	$ 1,299,481	$ 949,652
Commercial And Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	365,881	389,746
Real Estate Construction & Land [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	49,524	42,519
SBA [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	373,429	12,830
Other Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	1,731	1,628
Loans Receivable [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment	3,489	5,603
Loans collectively evaluated for impairment	1,295,992	944,049
Total gross loans	1,299,481	949,652
Loans individually evaluated for impairment	69	650
Loans collectively evaluated for impairment	12,455	10,425
Total allowance for loan losses	12,524	11,075
Loans Receivable [Member] \| Commercial And Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment	3,254	4,572
Loans collectively evaluated for impairment	362,627	385,174
Total gross loans	365,881	389,746
Loans individually evaluated for impairment	69	600
Loans collectively evaluated for impairment	7,782	6,108
Total allowance for loan losses	7,851	6,708
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	508,916	502,242
Total gross loans	508,916	502,929
Loans collectively evaluated for impairment	3,332	3,281
Total allowance for loan losses	3,332	3,281
Loans Receivable [Member] \| Real Estate Construction & Land [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans collectively evaluated for impairment	49,524	42,519
Total gross loans	49,524	42,519
Loans collectively evaluated for impairment	956	1,022
Total allowance for loan losses	956	1,022
Loans Receivable [Member] \| SBA [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment	235	344
Loans collectively evaluated for impairment	373,194	12,486
Total gross loans	373,429	12,830
Loans individually evaluated for impairment		50
Loans collectively evaluated for impairment	366	6
Total allowance for loan losses	366	6
Loans Receivable [Member] \| Other Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans collectively evaluated for impairment	1,731	1,628
Total gross loans	1,731	1,628
Loans collectively evaluated for impairment	19	8
Total allowance for loan losses	$ 19	$ 58

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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