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, 2021	Mar. 31, 2021	Dec. 31, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	$ 1,352,639		$ 1,369,070
Deferred loan origination (fees)/costs, net	(629)		523
Allowance for loan losses	(13,240)	$ (14,577)	(14,111)	$ (12,524)	$ (11,565)	$ (11,075)
Total loans, net	1,338,770		1,355,482
Commercial And Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	425,643		414,548
Allowance for loan losses	(8,133)	(9,231)	(8,923)	(7,851)	(7,843)	(6,708)
Real Estate - Other [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	616,451		550,690
Real Estate - Construction & Land [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	41,558		37,193
Allowance for loan losses	(697)	(798)	(681)	(956)	(730)	(1,022)
SBA [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	204,734		317,564
Allowance for loan losses	(317)	(575)	(604)	(366)	(321)	(50)
Other Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable Gross	64,253		49,075
Allowance for loan losses	$ (24)	$ (16)	$ (26)	$ (19)	$ (10)	$ (14)