LOANS AND ALLOWANCE FOR CREDIT LOSSES ON LOANS (Activity in Allowance for Credit Losses on Loans 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
Financing Receivable, Allowance for Credit Loss [Line Items]
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
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance				233	233
Commercial real estate - non owner-occupied
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	19,577		21,778	10,924	10,924
Loans charged off	0		0		(82)
Recoveries	0		0		107
Provision (credit)	157		(2,044)		11,497
Ending balance	19,734		19,734		21,778
Commercial real estate - non owner-occupied \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance				(668)	(668)
Commercial real estate - owner-occupied
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	2,516		2,832	1,490	1,490
Loans charged off	0		0		(21)
Recoveries	2		7		13
Provision (credit)	(214)		(535)		1,440
Ending balance	2,304		2,304		2,832
Commercial real estate - owner-occupied \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance				(90)	(90)
Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
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
Commercial \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance				1,548	1,548
SBA PPP Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
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
SBA PPP Portfolio Segment \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance				0	0
Residential real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
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
Residential real estate \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance				(1,129)	(1,129)
Home Equity
Financing Receivable, Allowance for Credit Loss [Line Items]
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
Home Equity \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance				792	792
Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
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
Consumer \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance				$ (220)	$ (220)

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

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