Loans and Allowance For Loan Losses - Summary of Outstanding Loans (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	$ 968,945	$ 949,652
Deferred loan origination costs, net	2,902	2,555
Allowance for loan losses	(11,565)	(11,075)	$ (11,250)	$ (10,800)
Total loans, net	960,282	941,132
Commercial And Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	416,308	389,746
Allowance for loan losses	(7,843)	(6,708)	(5,962)	(5,578)
Real Estate—Construction & Land [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	41,697	42,519
Allowance for loan losses	(730)	(1,022)	(1,120)	(1,493)
Real Estate—Other [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	496,765	502,929
Real Estate—HELOC [Member] [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	995	982
Allowance for loan losses	(5)	(6)	(10)	(16)
Installment and Other [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	13,180	13,476
Allowance for loan losses	$ (326)	$ (58)	$ (7)	$ (10)

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

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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.

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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