LOANS AND ALLOWANCE FOR LOAN LOSSES - Schedule of Activity in Allowance for Loan Losses (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Activity in allowance for loan losses
Balance, beginning of year	$ 14,655	$ 14,014	$ 12,796
Provision for loan losses	5,325	900	800
Charge-offs	(1,011)	(865)	(464)
Recoveries	1,182	606	882
Balance, end of year	20,151	14,655	14,014
Unallocated
Activity in allowance for loan losses
Balance, beginning of year	140	570	475
Provision for loan losses	78	(430)	95
Charge-offs	0	0	0
Recoveries	0	0	0
Balance, end of year	218	140	570
Commercial
Activity in allowance for loan losses
Balance, beginning of year	11,049	9,447	8,710
Provision for loan losses	4,927	1,497	177
Charge-offs	(751)	(324)	(24)
Recoveries	1,022	429	584
Balance, end of year	16,247	11,049	9,447
Commercial \| Commercial Real Estate
Activity in allowance for loan losses
Balance, beginning of year	7,634	6,876	6,763
Provision for loan losses	2,745	515	(442)
Charge-offs	(3)	(25)	(17)
Recoveries	775	268	572
Balance, end of year	11,151	7,634	6,876
Commercial \| Acquisition and Development
Activity in allowance for loan losses
Balance, beginning of year	959	817	417
Provision for loan losses	146	139	396
Charge-offs	0	0	(7)
Recoveries	9	3	11
Balance, end of year	1,114	959	817
Commercial \| Commercial and Industrial
Activity in allowance for loan losses
Balance, beginning of year	2,356	1,656	1,446
Provision for loan losses	2,096	841	209
Charge-offs	(748)	(299)	0
Recoveries	238	158	1
Balance, end of year	3,942	2,356	1,656
Commercial \| Municipal
Activity in allowance for loan losses
Balance, beginning of year	100	98	84
Provision for loan losses	(60)	2	14
Charge-offs	0	0	0
Recoveries	0	0	0
Balance, end of year	40	100	98
Consumer
Activity in allowance for loan losses
Balance, beginning of year	3,466	3,997	3,611
Provision for loan losses	320	(167)	528
Charge-offs	(260)	(541)	(440)
Recoveries	160	177	298
Balance, end of year	3,686	3,466	3,997
Consumer \| Residential Mortgage
Activity in allowance for loan losses
Balance, beginning of year	3,147	3,753	3,400
Provision for loan losses	203	(347)	363
Charge-offs	(114)	(386)	(148)
Recoveries	126	127	138
Balance, end of year	3,362	3,147	3,753
Consumer \| Installment and Other
Activity in allowance for loan losses
Balance, beginning of year	319	244	211
Provision for loan losses	117	180	165
Charge-offs	(146)	(155)	(292)
Recoveries	34	50	160
Balance, end of year	$ 324	$ 319	$ 244

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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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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