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	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	$ 37,865	$ 25,171	$ 25,171
Loans charged off	(287)	(490)	(1,838)
Recoveries	51	68	1,084
Provision	(1,854)	1,772	13,215
Ending balance	35,775	26,521	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	21,778	10,924	10,924
Loans charged off	0		(82)
Recoveries	0		107
Provision	695		11,497
Ending balance	22,473		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	2,832	1,490	1,490
Loans charged off	0		(21)
Recoveries	2		13
Provision	(286)		1,440
Ending balance	2,548		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 Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	6,703	3,985	3,985
Loans charged off	(147)	(253)	(1,130)
Recoveries	43	53	572
Provision	(1,429)	512	1,728
Ending balance	5,170	4,297	6,703
Commercial Portfolio Segment [Member] \| 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	69	0	0
Loans charged off	0		0
Recoveries	0		0
Provision	18		69
Ending balance	87		69
SBA PPP Portfolio Segment \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance		0	0
Residential Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	3,474	5,842	5,842
Loans charged off	(53)	(96)	(121)
Recoveries	0	2	292
Provision	(328)	149	(1,410)
Ending balance	3,093	5,897	3,474
Residential Portfolio Segment [Member] \| 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	2,616	2,423	2,423
Loans charged off	(38)	(34)	(317)
Recoveries	0	4	33
Provision	(402)	87	(315)
Ending balance	2,176	2,480	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	393	507	507
Loans charged off	(49)	(57)	(167)
Recoveries	6	5	67
Provision	(122)	18	206
Ending balance	$ 228	473	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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