Loans, Net, and Allowance for Loan Losses - Schedule of Allowance for Loan Losses Account by Major Classification of Loan (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Beginning balance	$ 12,140	$ 8,251	$ 12,200	$ 7,516
Allowance for Loan Losses, Charge-offs	(611)	(574)	(705)	(1,697)
Allowance for Loan Losses, Recoveries	73	47	107	105
Allowance for Loan Losses, Provision	(735)	2,012	(735)	3,812
Allowance for Loan Losses, Ending balance	10,867	9,736	10,867	9,736
Ending balance: individually evaluated for impairment	95		95
Ending balance: collectively evaluated for impairment	10,772		10,772		$ 12,200
Ending balance	948,740		948,740		1,139,239
Ending balance: individually evaluated for impairment	10,570		10,570		10,503
Ending balance: collectively evaluated for impairment	937,707		937,707		1,128,196
Ending balance: purchased credit impaired loans	463		463		540
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Beginning balance	1,393	1,671	1,705	1,953
Allowance for Loan Losses, Charge-offs	(201)		(210)	(899)
Allowance for Loan Losses, Recoveries	57	7	57	9
Allowance for Loan Losses, Provision	167	7	(136)	622
Allowance for Loan Losses, Ending balance	1,416	1,685	1,416	1,685
Ending balance: collectively evaluated for impairment	1,416		1,416		1,705
Ending balance	197,287		197,287		359,080
Ending balance: individually evaluated for impairment	974		974		1,565
Ending balance: collectively evaluated for impairment	196,313		196,313		357,515
Real Estate Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Beginning balance	1,134	695	1,117	473
Allowance for Loan Losses, Charge-offs			(37)
Allowance for Loan Losses, Provision	(381)	46	(327)	268
Allowance for Loan Losses, Ending balance	753	741	753	741
Ending balance: collectively evaluated for impairment	753		753		1,117
Ending balance	55,500		55,500		73,402
Ending balance: individually evaluated for impairment	957		957
Ending balance: collectively evaluated for impairment	54,543		54,543		73,402
Real Estate Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Beginning balance	6,793	3,917	6,494	3,115
Allowance for Loan Losses, Charge-offs	(373)	(501)	(373)	(595)
Allowance for Loan Losses, Recoveries	2	2	3	2
Allowance for Loan Losses, Provision	(57)	1,660	241	2,556
Allowance for Loan Losses, Ending balance	6,365	5,078	6,365	5,078
Ending balance: individually evaluated for impairment	95		95
Ending balance: collectively evaluated for impairment	6,270		6,270		6,494
Ending balance	502,471		502,471		502,495
Ending balance: individually evaluated for impairment	6,284		6,284		6,444
Ending balance: collectively evaluated for impairment	495,870		495,870		495,674
Ending balance: purchased credit impaired loans	317		317		377
Real Estate Residential [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Beginning balance	2,236	1,713	2,427	1,820
Allowance for Loan Losses, Charge-offs		(2)		(2)
Allowance for Loan Losses, Recoveries		1	2	1
Allowance for Loan Losses, Provision	(378)	358	(571)	251
Allowance for Loan Losses, Ending balance	1,858	2,070	1,858	2,070
Ending balance: collectively evaluated for impairment	1,858		1,858		2,427
Ending balance	187,479		187,479		197,596
Ending balance: individually evaluated for impairment	2,355		2,355		2,494
Ending balance: collectively evaluated for impairment	184,978		184,978		194,939
Ending balance: purchased credit impaired loans	146		146		163
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Beginning balance	127	152	142	155
Allowance for Loan Losses, Charge-offs	(37)	(71)	(85)	(201)
Allowance for Loan Losses, Recoveries	14	37	45	93
Allowance for Loan Losses, Provision	7	44	9	115
Allowance for Loan Losses, Ending balance	111	162	111	$ 162
Ending balance: collectively evaluated for impairment	111		111		142
Ending balance	6,003		6,003		6,666
Ending balance: collectively evaluated for impairment	6,003		6,003		6,666
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Beginning balance	457	103	315
Allowance for Loan Losses, Provision	(93)	$ (103)	49
Allowance for Loan Losses, Ending balance	364		364
Ending balance: collectively evaluated for impairment	364		364		$ 315
Ending balance: purchased credit impaired loans	$ 364		$ 364

Financing Receivable Purchase Credit Impaired Loans

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Provision for loan lease and other losses (gains).

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

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount before allowance and after 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.

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