LOANS AND ALLOWANCE FOR LOAN LOSSES - Schedule of Activity in Allowance for Loan Losses (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Activity in allowance for loan losses
Balance, beginning of year	$ 14,014	$ 12,796	$ 12,775
Provision for loan losses	900	800	1,000
Charge-offs	(865)	(464)	(1,266)
Recoveries	606	882	287
Balance, end of year	14,655	14,014	12,796
Unallocated
Activity in allowance for loan losses
Balance, beginning of year	570	475	414
Provision for loan losses	(430)	95	61
Charge-offs	0	0	0
Recoveries	0	0	0
Balance, end of year	140	570	475
Commercial
Activity in allowance for loan losses
Balance, beginning of year	9,447	8,710	9,238
Provision for loan losses	1,497	177	234
Charge-offs	(324)	(24)	(920)
Recoveries	429	584	158
Balance, end of year	11,049	9,447	8,710
Commercial \| Commercial Real Estate
Activity in allowance for loan losses
Balance, beginning of year	6,876	6,763	7,530
Provision for loan losses	515	(442)	38
Charge-offs	(25)	(17)	(835)
Recoveries	268	572	30
Balance, end of year	7,634	6,876	6,763
Commercial \| Acquisition and Development
Activity in allowance for loan losses
Balance, beginning of year	817	417	580
Provision for loan losses	139	396	(167)
Charge-offs	0	(7)	0
Recoveries	3	11	4
Balance, end of year	959	817	417
Commercial \| Commercial and Industrial
Activity in allowance for loan losses
Balance, beginning of year	1,656	1,446	1,074
Provision for loan losses	841	209	333
Charge-offs	(299)	0	(85)
Recoveries	158	1	124
Balance, end of year	2,356	1,656	1,446
Commercial \| Municipal
Activity in allowance for loan losses
Balance, beginning of year	98	84	54
Provision for loan losses	2	14	30
Charge-offs	0	0	0
Recoveries	0	0	0
Balance, end of year	100	98	84
Consumer
Activity in allowance for loan losses
Balance, beginning of year	3,997	3,611	3,123
Provision for loan losses	(167)	528	705
Charge-offs	(541)	(440)	(346)
Recoveries	177	298	129
Balance, end of year	3,466	3,997	3,611
Consumer \| Residential Mortgage
Activity in allowance for loan losses
Balance, beginning of year	3,753	3,400	2,979
Provision for loan losses	(347)	363	531
Charge-offs	(386)	(148)	(180)
Recoveries	127	138	70
Balance, end of year	3,147	3,753	3,400
Consumer \| Installment and Other
Activity in allowance for loan losses
Balance, beginning of year	244	211	144
Provision for loan losses	180	165	174
Charge-offs	(155)	(292)	(166)
Recoveries	50	160	59
Balance, end of year	$ 319	$ 244	$ 211

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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Amount of expense related to estimated loss from loan and lease transactions.

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