ALLOWANCE FOR LOAN LOSSES - Allowance Activity (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Activity in the allowance for loan losses
Balance at beginning of period			$ 12,325
Provision (releases) for loan losses	$ 643	$ 660	2,208	$ 2,191
Balance at end of period	13,487		13,487
Allowance For Loan Losses
Total	13,487		12,325		$ 13,487
Business Activities Loans
Activity in the allowance for loan losses
Balance at beginning of period	12,723	11,333	12,153	10,419
Charged-off loans	(130)	(175)	(784)	(732)
Recoveries on charged-off loans	27	145	98	194
Provision (releases) for loan losses	584	274	1,737	1,696
Balance at end of period	13,204	11,577	13,204	11,577
Allowance For Loan Losses
Individually evaluated for impairment					842	$ 492
Collectively evaluated					12,362	11,085
Total	12,723	11,333	12,153	10,419	13,204	11,577
Business Activities Loans \| Commercial real estate
Activity in the allowance for loan losses
Balance at beginning of period	6,367	5,503	6,037	5,145
Charged-off loans	(29)	(12)	(186)	(124)
Recoveries on charged-off loans	7	49	68	52
Provision (releases) for loan losses	291	(200)	717	267
Balance at end of period	6,636	5,340	6,636	5,340
Allowance For Loan Losses
Individually evaluated for impairment					688	391
Collectively evaluated					5,948	4,949
Total	6,367	5,503	6,037	5,145	6,636	5,340
Business Activities Loans \| Commercial and industrial
Activity in the allowance for loan losses
Balance at beginning of period	2,509	2,110	2,373	1,952
Charged-off loans	0	0	(111)	(187)
Recoveries on charged-off loans	18	24	23	56
Provision (releases) for loan losses	(31)	41	211	354
Balance at end of period	2,496	2,175	2,496	2,175
Allowance For Loan Losses
Individually evaluated for impairment					62	2
Collectively evaluated					2,434	2,173
Total	2,509	2,110	2,373	1,952	2,496	2,175
Business Activities Loans \| Residential real estate
Activity in the allowance for loan losses
Balance at beginning of period	3,454	3,119	3,357	2,721
Charged-off loans	(61)	(114)	(61)	(326)
Recoveries on charged-off loans	0	66	2	67
Provision (releases) for loan losses	258	430	353	1,039
Balance at end of period	3,651	3,501	3,651	3,501
Allowance For Loan Losses
Individually evaluated for impairment					92	44
Collectively evaluated					3,559	3,457
Total	3,454	3,119	3,357	2,721	3,651	3,501
Business Activities Loans \| Consumer
Activity in the allowance for loan losses
Balance at beginning of period	393	601	386	601
Charged-off loans	(40)	(49)	(426)	(95)
Recoveries on charged-off loans	2	6	5	19
Provision (releases) for loan losses	66	3	456	36
Balance at end of period	421	561	421	561
Allowance For Loan Losses
Individually evaluated for impairment					0	55
Collectively evaluated					421	506
Total	393	601	386	601	421	561
Acquired Loans
Activity in the allowance for loan losses
Balance at beginning of period	367	109	172	0
Charged-off loans	(168)	(122)	(492)	(122)
Recoveries on charged-off loans	25	0	132	0
Provision (releases) for loan losses	59	386	471	495
Balance at end of period	283	373	283	373
Allowance For Loan Losses
Individually evaluated for impairment					20	168
Collectively evaluated					263	205
Total	367	109	172	0	283	373
Acquired Loans \| Commercial real estate
Activity in the allowance for loan losses
Balance at beginning of period	200	51	97	0
Charged-off loans	(30)	(54)	(136)	(54)
Recoveries on charged-off loans	25	0	43	0
Provision (releases) for loan losses	(23)	309	168	360
Balance at end of period	172	306	172	306
Allowance For Loan Losses
Individually evaluated for impairment					0	168
Collectively evaluated					172	138
Total	200	51	97	0	172	306
Acquired Loans \| Commercial and industrial
Activity in the allowance for loan losses
Balance at beginning of period	82	24	16	0
Charged-off loans	(71)	(18)	(166)	(18)
Recoveries on charged-off loans	0	0	7	0
Provision (releases) for loan losses	33	25	187	49
Balance at end of period	44	31	44	31
Allowance For Loan Losses
Individually evaluated for impairment					0	0
Collectively evaluated					44	31
Total	82	24	16	0	44	31
Acquired Loans \| Residential real estate
Activity in the allowance for loan losses
Balance at beginning of period	85	34	59	0
Charged-off loans	(62)	(31)	(126)	(31)
Recoveries on charged-off loans	0	0	0	0
Provision (releases) for loan losses	44	33	134	67
Balance at end of period	67	36	67	36
Allowance For Loan Losses
Individually evaluated for impairment					20	0
Collectively evaluated					47	36
Total	85	34	59	0	67	36
Acquired Loans \| Consumer
Activity in the allowance for loan losses
Balance at beginning of period	0	0	0	0
Charged-off loans	(5)	(19)	(64)	(19)
Recoveries on charged-off loans	0	0	82	0
Provision (releases) for loan losses	5	19	(18)	19
Balance at end of period	0	0	0	0
Allowance For Loan Losses
Individually evaluated for impairment					0	0
Collectively evaluated					0	0
Total	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0

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

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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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