LOANS AND ALLOWANCE FOR CREDIT LOSSES ON LOANS (Activity in Allowance for Loan Losses by Portfolio Segment) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Activity in ALL:
Beginning balance	$ 32,060	$ 35,539	$ 37,865	$ 25,171	$ 25,171
Loans charged off	(121)	(307)	(828)	(1,281)	(1,838)
Recoveries	64	182	272	352	1,084
Provision (credit)	269	1,000	(5,037)	12,172	13,215
Ending balance	32,272	36,414	32,272	36,414	37,865
Ending Balance: Individually evaluated for impairment		494		494
Ending Balance: Collectively evaluated for impairment		35,920		35,920
Ending Balance: Individually evaluated for impairment		4,124		4,124
Ending Balance: Collectively evaluated for impairment		3,270,718		3,270,718
Total Loans Outstanding	3,315,303	3,274,842	3,315,303	3,274,842	3,219,822
Commercial Real Estate(1)
Activity in ALL:
Beginning balance		18,386		12,414	12,414
Loans charged off		(33)		(104)
Recoveries		3		10
Provision (credit)		1,173		7,209
Ending balance		19,529		19,529
Ending Balance: Individually evaluated for impairment		36		36
Ending Balance: Collectively evaluated for impairment		19,493		19,493
Ending Balance: Individually evaluated for impairment		460		460
Ending Balance: Collectively evaluated for impairment		1,333,273		1,333,273
Total Loans Outstanding		1,333,733		1,333,733
Commercial
Activity in ALL:
Beginning balance	4,342	4,849	6,703	3,985	3,985
Loans charged off	(97)	(184)	(503)	(857)	(1,130)
Recoveries	49	139	159	255	572
Provision (credit)	295	(267)	(1,770)	1,154	1,728
Ending balance	4,589	4,537	4,589	4,537	6,703
Ending Balance: Individually evaluated for impairment		0		0
Ending Balance: Collectively evaluated for impairment		4,537		4,537
Ending Balance: Individually evaluated for impairment		171		171
Ending Balance: Collectively evaluated for impairment		375,377		375,377
Total Loans Outstanding		375,548		375,548
SBA PPP Portfolio Segment
Activity in ALL:
Beginning balance	66	113	69	0	0
Loans charged off	0	0	0	0	0
Recoveries	0	0	0	0	0
Provision (credit)	(23)	2	(26)	115	69
Ending balance	43	115	43	115	69
Ending Balance: Individually evaluated for impairment		0		0
Ending Balance: Collectively evaluated for impairment		115		115
Ending Balance: Individually evaluated for impairment		0		0
Ending Balance: Collectively evaluated for impairment		223,838		223,838
Total Loans Outstanding		223,838		223,838
Residential Real Estate
Activity in ALL:
Beginning balance	3,205	8,603	3,474	5,842	5,842
Loans charged off	(4)	(25)	(92)	(121)	(121)
Recoveries	2	4	72	27	292
Provision (credit)	450	124	199	2,958	(1,410)
Ending balance	3,653	8,706	3,653	8,706	3,474
Ending Balance: Individually evaluated for impairment		371		371
Ending Balance: Collectively evaluated for impairment		8,335		8,335
Ending Balance: Individually evaluated for impairment		3,128		3,128
Ending Balance: Collectively evaluated for impairment		1,040,975		1,040,975
Total Loans Outstanding		1,044,103		1,044,103
Home Equity
Activity in ALL:
Beginning balance	2,065	3,084	2,616	2,423	2,423
Loans charged off	0	(10)	(145)	(61)	(317)
Recoveries	4	0	4	4	33
Provision (credit)	(231)	(51)	(637)	657	(315)
Ending balance	1,838	3,023	1,838	3,023	2,616
Ending Balance: Individually evaluated for impairment		87		87
Ending Balance: Collectively evaluated for impairment		2,936		2,936
Ending Balance: Individually evaluated for impairment		365		365
Ending Balance: Collectively evaluated for impairment		274,378		274,378
Total Loans Outstanding		274,743		274,743
Consumer
Activity in ALL:
Beginning balance	289	504	393	507	507
Loans charged off	(20)	(55)	(88)	(138)	(167)
Recoveries	7	36	30	56	67
Provision (credit)	(165)	19	(224)	79	206
Ending balance	$ 111	504	$ 111	504	$ 393
Ending Balance: Individually evaluated for impairment		0		0
Ending Balance: Collectively evaluated for impairment		504		504
Ending Balance: Individually evaluated for impairment		0		0
Ending Balance: Collectively evaluated for impairment		22,877		22,877
Total Loans Outstanding		$ 22,877		$ 22,877

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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