LOANS AND ALLOWANCE FOR LOAN AND LEASE LOSSES - TDR MODIFICATIONS (Details)	12 Months Ended
	Dec. 31, 2019 USD ($) loan	Dec. 31, 2018 USD ($) loan	Dec. 31, 2017 USD ($) loan
Troubled Debt Restructurings disclosures
Period of time loans are not past due in which TDR loans are performing	30 days
Number of Loans | loan	1,828	495
Recorded Investment	$ 30,781,000	$ 32,863,000
Commitments to lend any additional material amounts to existing TDR relationships	0	0
Change between the pre and post modification loan	$ 0	$ 0	$ 0
Residential Real Estate
Troubled Debt Restructurings disclosures
Number of Loans | loan	194	216
Recorded Investment	$ 19,770,000	$ 23,610,000
Residential Real Estate | Interest only payments
Troubled Debt Restructurings disclosures
Number of Loans | loan	1	1
Recorded Investment	$ 904,000	$ 970,000
Residential Real Estate | Rate reduction
Troubled Debt Restructurings disclosures
Number of Loans | loan	123	157
Recorded Investment	$ 14,199,000	$ 17,870,000
Residential Real Estate | Principal deferral
Troubled Debt Restructurings disclosures
Number of Loans | loan	10	15
Recorded Investment	$ 1,024,000	$ 3,042,000
Residential Real Estate | Legal modifications
Troubled Debt Restructurings disclosures
Number of Loans | loan	60	43
Recorded Investment	$ 3,643,000	$ 1,728,000
Commercial Real Estate and Commercial Construction
Troubled Debt Restructurings disclosures
Number of Loans | loan	21	23
Recorded Investment	$ 10,425,000	$ 8,818,000
Commercial Real Estate and Commercial Construction | Interest only payments
Troubled Debt Restructurings disclosures
Number of Loans | loan	3	2
Recorded Investment	$ 1,568,000	$ 752,000
Commercial Real Estate and Commercial Construction | Rate reduction
Troubled Debt Restructurings disclosures
Number of Loans | loan	4	8
Recorded Investment	$ 1,252,000	$ 2,962,000
Commercial Real Estate and Commercial Construction | Principal deferral
Troubled Debt Restructurings disclosures
Number of Loans | loan	12	12
Recorded Investment	$ 6,578,000	$ 5,076,000
Commercial Real Estate and Commercial Construction | Legal modifications
Troubled Debt Restructurings disclosures
Number of Loans | loan	2	1
Recorded Investment	$ 1,027,000	$ 28,000
Consumer and other
Troubled Debt Restructurings disclosures
Number of Loans | loan	1,613	256
Recorded Investment	$ 586,000	$ 435,000
Consumer and other | Rate reduction
Troubled Debt Restructurings disclosures
Number of Loans | loan		1
Recorded Investment		$ 16,000
Consumer and other | Principal deferral
Troubled Debt Restructurings disclosures
Number of Loans | loan	1,612	255
Recorded Investment	$ 577,000	$ 419,000
Consumer and other | Legal modifications
Troubled Debt Restructurings disclosures
Number of Loans | loan	1
Recorded Investment	$ 9,000
Consumer
Troubled Debt Restructurings disclosures
Number of Loans | loan	1,613	256
Recorded Investment	$ 586,000	$ 435,000
Modified During The Period
Troubled Debt Restructurings disclosures
Number of Loans | loan	1,320	25	845
Recorded Investment	$ 8,599,000	$ 4,948,000	$ 2,683,000
Modified During The Period | Residential Real Estate
Troubled Debt Restructurings disclosures
Number of Loans | loan	32	17	13
Recorded Investment	$ 2,740,000	$ 3,466,000	$ 1,780,000
Modified During The Period | Residential Real Estate | Interest only payments
Troubled Debt Restructurings disclosures
Number of Loans | loan		1	1
Recorded Investment		$ 970,000	$ 219,000
Modified During The Period | Residential Real Estate | Rate reduction
Troubled Debt Restructurings disclosures
Number of Loans | loan	1	2	4
Recorded Investment	$ 365,000	$ 465,000	$ 1,013,000
Modified During The Period | Residential Real Estate | Principal deferral
Troubled Debt Restructurings disclosures
Number of Loans | loan		6
Recorded Investment		$ 1,892,000
Modified During The Period | Residential Real Estate | Legal modifications
Troubled Debt Restructurings disclosures
Number of Loans | loan	31	8	8
Recorded Investment	$ 2,375,000	$ 139,000	$ 548,000
Modified During The Period | Commercial Real Estate and Commercial Construction
Troubled Debt Restructurings disclosures
Number of Loans | loan	8	7	2
Recorded Investment	$ 5,649,000	$ 1,430,000	$ 266,000
Modified During The Period | Commercial Real Estate and Commercial Construction | Interest only payments
Troubled Debt Restructurings disclosures
Number of Loans | loan	2
Recorded Investment	$ 1,423,000
Modified During The Period | Commercial Real Estate and Commercial Construction | Principal deferral
Troubled Debt Restructurings disclosures
Number of Loans | loan	4	6	2
Recorded Investment	$ 3,199,000	$ 1,402,000	$ 266,000
Modified During The Period | Commercial Real Estate and Commercial Construction | Legal modifications
Troubled Debt Restructurings disclosures
Number of Loans | loan	2	1
Recorded Investment	$ 1,027,000	$ 28,000
Modified During The Period | Consumer and other
Troubled Debt Restructurings disclosures
Number of Loans | loan	1,280	1	830
Recorded Investment	$ 210,000	$ 52,000	$ 637,000
Modified During The Period | Consumer and other | Principal deferral
Troubled Debt Restructurings disclosures
Number of Loans | loan	1,279	1	830
Recorded Investment	$ 201,000	$ 52,000	$ 637,000
Modified During The Period | Consumer and other | Legal modifications
Troubled Debt Restructurings disclosures
Number of Loans | loan	1
Recorded Investment	$ 9,000
Performing Financing Receivable
Troubled Debt Restructurings disclosures
Number of Loans | loan	1,811	469
Recorded Investment	$ 28,138,000	$ 28,788,000
Percentage of troubled debt restructurings performing as per terms of modifications	91.00%	88.00%
Specific reserve allocations made to customers	$ 2,000,000	$ 3,000,000
Percentage of Bank's TDRs that occurred during period, which were performing according to their modified terms	83.00%	42.00%	93.00%
Specific reserve allocations made to customers whose loan terms were modified in TDRs during period	$ 220,000	$ 472,000	$ 885,000
Performing Financing Receivable | Residential Real Estate
Troubled Debt Restructurings disclosures
Number of Loans | loan	181	191
Recorded Investment	$ 18,796,000	$ 19,563,000
Performing Financing Receivable | Residential Real Estate | Interest only payments
Troubled Debt Restructurings disclosures
Number of Loans | loan	1
Recorded Investment	$ 904,000
Performing Financing Receivable | Residential Real Estate | Rate reduction
Troubled Debt Restructurings disclosures
Number of Loans | loan	118	145
Recorded Investment	$ 13,847,000	$ 16,892,000
Performing Financing Receivable | Residential Real Estate | Principal deferral
Troubled Debt Restructurings disclosures
Number of Loans | loan	8	11
Recorded Investment	$ 845,000	$ 1,171,000
Performing Financing Receivable | Residential Real Estate | Legal modifications
Troubled Debt Restructurings disclosures
Number of Loans | loan	54	35
Recorded Investment	$ 3,200,000	$ 1,500,000
Performing Financing Receivable | Commercial Real Estate and Commercial Construction
Troubled Debt Restructurings disclosures
Number of Loans | loan	17	22
Recorded Investment	$ 8,756,000	$ 8,790,000
Performing Financing Receivable | Commercial Real Estate and Commercial Construction | Interest only payments
Troubled Debt Restructurings disclosures
Number of Loans | loan	3	2
Recorded Investment	$ 1,568,000	$ 752,000
Performing Financing Receivable | Commercial Real Estate and Commercial Construction | Rate reduction
Troubled Debt Restructurings disclosures
Number of Loans | loan	3	8
Recorded Investment	$ 1,207,000	$ 2,962,000
Performing Financing Receivable | Commercial Real Estate and Commercial Construction | Principal deferral
Troubled Debt Restructurings disclosures
Number of Loans | loan	11	12
Recorded Investment	$ 5,981,000	$ 5,076,000
Performing Financing Receivable | Consumer and other
Troubled Debt Restructurings disclosures
Number of Loans | loan	1,613	256
Recorded Investment	$ 586,000	$ 435,000
Performing Financing Receivable | Consumer and other | Rate reduction
Troubled Debt Restructurings disclosures
Number of Loans | loan		1
Recorded Investment		$ 16,000
Performing Financing Receivable | Consumer and other | Principal deferral
Troubled Debt Restructurings disclosures
Number of Loans | loan	1,612	255
Recorded Investment	$ 577,000	$ 419,000
Performing Financing Receivable | Consumer and other | Legal modifications
Troubled Debt Restructurings disclosures
Number of Loans | loan	1
Recorded Investment	$ 9,000
Performing Financing Receivable | Modified During The Period
Troubled Debt Restructurings disclosures
Number of Loans | loan	1,313	19	843
Recorded Investment	$ 7,155,000	$ 2,083,000	$ 2,486,000
Performing Financing Receivable | Modified During The Period | Residential Real Estate
Troubled Debt Restructurings disclosures
Number of Loans | loan	27	12	11
Recorded Investment	$ 2,323,000	$ 629,000	$ 1,583,000
Performing Financing Receivable | Modified During The Period | Residential Real Estate | Interest only payments
Troubled Debt Restructurings disclosures
Number of Loans | loan			1
Recorded Investment			$ 219,000
Performing Financing Receivable | Modified During The Period | Residential Real Estate | Rate reduction
Troubled Debt Restructurings disclosures
Number of Loans | loan	1	2	4
Recorded Investment	$ 365,000	$ 465,000	$ 1,013,000
Performing Financing Receivable | Modified During The Period | Residential Real Estate | Principal deferral
Troubled Debt Restructurings disclosures
Number of Loans | loan		3
Recorded Investment		$ 43,000
Performing Financing Receivable | Modified During The Period | Residential Real Estate | Legal modifications
Troubled Debt Restructurings disclosures
Number of Loans | loan	26	7	6
Recorded Investment	$ 1,958,000	$ 121,000	$ 351,000
Performing Financing Receivable | Modified During The Period | Commercial Real Estate and Commercial Construction
Troubled Debt Restructurings disclosures
Number of Loans | loan	6	6	2
Recorded Investment	$ 4,622,000	$ 1,402,000	$ 266,000
Performing Financing Receivable | Modified During The Period | Commercial Real Estate and Commercial Construction | Interest only payments
Troubled Debt Restructurings disclosures
Number of Loans | loan	2
Recorded Investment	$ 1,423,000
Performing Financing Receivable | Modified During The Period | Commercial Real Estate and Commercial Construction | Principal deferral
Troubled Debt Restructurings disclosures
Number of Loans | loan	4	6	2
Recorded Investment	$ 3,199,000	$ 1,402,000	$ 266,000
Performing Financing Receivable | Modified During The Period | Consumer and other
Troubled Debt Restructurings disclosures
Number of Loans | loan	1,280	1	830
Recorded Investment	$ 210,000	$ 52,000	$ 637,000
Performing Financing Receivable | Modified During The Period | Consumer and other | Principal deferral
Troubled Debt Restructurings disclosures
Number of Loans | loan	1,279	1	830
Recorded Investment	$ 201,000	$ 52,000	$ 637,000
Performing Financing Receivable | Modified During The Period | Consumer and other | Legal modifications
Troubled Debt Restructurings disclosures
Number of Loans | loan	1
Recorded Investment	$ 9,000
Nonperforming Financing Receivable
Troubled Debt Restructurings disclosures
Number of Loans | loan	17	26
Recorded Investment	$ 2,643,000	$ 4,075,000
Nonperforming Financing Receivable | Residential Real Estate
Troubled Debt Restructurings disclosures
Number of Loans | loan	13	25
Recorded Investment	$ 974,000	$ 4,047,000
Nonperforming Financing Receivable | Residential Real Estate | Interest only payments
Troubled Debt Restructurings disclosures
Number of Loans | loan		1
Recorded Investment		$ 970,000
Nonperforming Financing Receivable | Residential Real Estate | Rate reduction
Troubled Debt Restructurings disclosures
Number of Loans | loan	5	12
Recorded Investment	$ 352,000	$ 978,000
Nonperforming Financing Receivable | Residential Real Estate | Principal deferral
Troubled Debt Restructurings disclosures
Number of Loans | loan	2	4
Recorded Investment	$ 179,000	$ 1,871,000
Nonperforming Financing Receivable | Residential Real Estate | Legal modifications
Troubled Debt Restructurings disclosures
Number of Loans | loan	6	8
Recorded Investment	$ 443,000	$ 228,000
Nonperforming Financing Receivable | Commercial Real Estate and Commercial Construction
Troubled Debt Restructurings disclosures
Number of Loans | loan	4	1
Recorded Investment	$ 1,669,000	$ 28,000
Nonperforming Financing Receivable | Commercial Real Estate and Commercial Construction | Rate reduction
Troubled Debt Restructurings disclosures
Number of Loans | loan	1
Recorded Investment	$ 45,000
Nonperforming Financing Receivable | Commercial Real Estate and Commercial Construction | Principal deferral
Troubled Debt Restructurings disclosures
Number of Loans | loan	1
Recorded Investment	$ 597,000
Nonperforming Financing Receivable | Commercial Real Estate and Commercial Construction | Legal modifications
Troubled Debt Restructurings disclosures
Number of Loans | loan	2	1
Recorded Investment	$ 1,027,000	$ 28,000
Nonperforming Financing Receivable | Modified During The Period
Troubled Debt Restructurings disclosures
Number of Loans	7	6	2
Recorded Investment	$ 1,444,000	$ 2,865,000	$ 197,000
Nonperforming Financing Receivable | Modified During The Period | Residential Real Estate
Troubled Debt Restructurings disclosures
Number of Loans	5	5	2
Recorded Investment	$ 417,000	$ 2,837,000	$ 197,000
Nonperforming Financing Receivable | Modified During The Period | Residential Real Estate | Interest only payments
Troubled Debt Restructurings disclosures
Number of Loans | loan		1
Recorded Investment		$ 970,000
Nonperforming Financing Receivable | Modified During The Period | Residential Real Estate | Principal deferral
Troubled Debt Restructurings disclosures
Number of Loans | loan		3
Recorded Investment		$ 1,849,000
Nonperforming Financing Receivable | Modified During The Period | Residential Real Estate | Legal modifications
Troubled Debt Restructurings disclosures
Number of Loans	5	1	2
Recorded Investment	$ 417,000	$ 18,000	$ 197,000
Nonperforming Financing Receivable | Modified During The Period | Commercial Real Estate and Commercial Construction
Troubled Debt Restructurings disclosures
Number of Loans	2	1
Recorded Investment	$ 1,027,000	$ 28,000
Nonperforming Financing Receivable | Modified During The Period | Commercial Real Estate and Commercial Construction | Legal modifications
Troubled Debt Restructurings disclosures
Number of Loans	2	1
Recorded Investment	$ 1,027,000	$ 28,000