ALLOWANCE FOR LOAN LOSSES - Allowance Activity (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Activity in the allowance for loan losses
Balance at beginning of period			$ 15,353
Provision (release) for loan losses	$ 1,800	$ 893	4,265	$ 1,779
Balance at end of period	17,907		17,907
Allowance For Loan Losses
Total	17,907		15,353		$ 17,907
Business Activities Loans
Activity in the allowance for loan losses
Balance at beginning of period	15,978	14,290	15,057	13,581
Charged-off loans	(416)	(163)	(1,699)	(309)
Recoveries on charged-off loans	32	100	111	256
Provision (release) for loan losses	1,781	814	3,906	1,513
Balance at end of period	17,375	15,041	17,375	15,041
Allowance For Loan Losses
Individually evaluated for impairment					632	$ 1,297
Collectively evaluated					16,743	13,744
Total	17,375	15,041	15,057	15,041	17,375	15,041
Business Activities Loans \| Total commercial real estate
Activity in the allowance for loan losses
Balance at beginning of period	8,416	7,206	7,668	6,811
Charged-off loans	(266)		(1,036)	(57)
Recoveries on charged-off loans	12	1	90	131
Provision (release) for loan losses	1,265	956	2,705	1,278
Balance at end of period	9,427	8,163	9,427	8,163
Allowance For Loan Losses
Individually evaluated for impairment					343	990
Collectively evaluated					9,084	7,173
Total	9,427	8,163	9,427	8,163	9,427	8,163
Business Activities Loans \| Commercial and industrial
Activity in the allowance for loan losses
Balance at beginning of period	3,241	2,748	3,608	2,380
Charged-off loans	(4)		(307)	(13)
Recoveries on charged-off loans	14	62	16	62
Provision (release) for loan losses	269	63	203	444
Balance at end of period	3,520	2,873	3,520	2,873
Allowance For Loan Losses
Individually evaluated for impairment					243	240
Collectively evaluated					3,277	2,633
Total	3,520	2,873	3,608	2,380	3,520	2,873
Business Activities Loans \| Total residential real estate
Activity in the allowance for loan losses
Balance at beginning of period	3,945	3,942	3,402	3,982
Charged-off loans		(108)	(21)	(110)
Recoveries on charged-off loans		36		55
Provision (release) for loan losses	104	(111)	668	(168)
Balance at end of period	4,049	3,759	4,049	3,759
Allowance For Loan Losses
Individually evaluated for impairment					45	66
Collectively evaluated					4,004	3,693
Total	4,049	3,759	3,402	3,759	4,049	3,759
Business Activities Loans \| Total consumer
Activity in the allowance for loan losses
Balance at beginning of period	376	394	379	408
Charged-off loans	(146)	(55)	(335)	(129)
Recoveries on charged-off loans	6	1	5	8
Provision (release) for loan losses	143	(94)	330	(41)
Balance at end of period	379	246	379	246
Allowance For Loan Losses
Individually evaluated for impairment					1	1
Collectively evaluated					378	245
Total	379	246	379	408	379	246
Acquired Loans
Activity in the allowance for loan losses
Balance at beginning of period	531	282	296	285
Charged-off loans	(23)	(52)	(171)	(242)
Recoveries on charged-off loans	5	3	48	3
Provision (release) for loan losses	19	79	359	266
Balance at end of period	532	312	532	312
Allowance For Loan Losses
Individually evaluated for impairment					356	44
Collectively evaluated					176	268
Total	532	312	296	285	532	312
Acquired Loans \| Total commercial real estate
Activity in the allowance for loan losses
Balance at beginning of period	401	159	147	173
Charged-off loans			(101)
Recoveries on charged-off loans	2		19
Provision (release) for loan losses	(3)	(2)	335	(16)
Balance at end of period	400	157	400	157
Allowance For Loan Losses
Individually evaluated for impairment					297	12
Collectively evaluated					103	145
Total	400	157	147	173	400	157
Acquired Loans \| Commercial and industrial
Activity in the allowance for loan losses
Balance at beginning of period	12	22	6	35
Charged-off loans	(20)		(53)	(15)
Recoveries on charged-off loans			9
Provision (release) for loan losses	20	(15)	50	(13)
Balance at end of period	12	7	12	7
Allowance For Loan Losses
Individually evaluated for impairment					7
Collectively evaluated					5	7
Total	12	7	6	35	12	7
Acquired Loans \| Total residential real estate
Activity in the allowance for loan losses
Balance at beginning of period	118	101	143	77
Charged-off loans		(52)	(11)	(222)
Recoveries on charged-off loans	1		12
Provision (release) for loan losses	1	99	(24)	293
Balance at end of period	120	148	120	148
Allowance For Loan Losses
Individually evaluated for impairment					52	32
Collectively evaluated					68	116
Total	120	148	143	77	$ 120	$ 148
Acquired Loans \| Total consumer
Activity in the allowance for loan losses
Charged-off loans	(3)		(6)	(5)
Recoveries on charged-off loans	2	3	8	3
Provision (release) for loan losses	$ 1	$ (3)	$ (2)	$ 2

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 valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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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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