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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Loans and Allowance For Loan Losses - Summary of Outstanding Loans (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	$ 1,299,481		$ 949,652
Deferred loan origination (fees)/costs, net	(1,569)		2,555
Allowance for loan losses	(12,524)	$ (11,565)	(11,075)	$ (11,501)	$ (11,250)	$ (10,800)
Total loans, net	1,285,388		941,132
Commercial And Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	365,881		389,746
Allowance for loan losses	(7,851)	(7,843)	(6,708)	(7,654)	(5,826)	(5,401)
Real Estate - Other [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	508,916		502,929
Real Estate - Construction & Land [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	49,524		42,519
Allowance for loan losses	(956)	(730)	(1,022)	(945)	(1,120)	(1,524)
SBA [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	373,429		12,830
Allowance for loan losses	(366)	(321)	(50)	(199)	(188)	(172)
Other Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	1,731		1,628
Allowance for loan losses	$ (19)	$ (10)	$ (14)	$ (15)	$ (17)	$ (26)