LOANS - Summary of Impaired Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Business Activities Loans
Recorded Investment
Total	$ 13,893	$ 9,647
Unpaid Principal Balance
Total	16,016	11,653
Related Allowance
With an allowance recorded:	649	459
Business Activities Loans \| Total Commercial Real Estate
Recorded Investment
Total	7,641	7,604
Unpaid Principal Balance
Total	9,639	9,598
Related Allowance
With an allowance recorded:	433	447
Business Activities Loans \| Total Commercial Real Estate \| Construction and land development
Recorded Investment
With no related allowance:	566	0
With an allowance recorded:	0	637
Unpaid Principal Balance
With no related allowance:	2,491	0
With an allowance recorded:	0	2,563
Related Allowance
With an allowance recorded:	0	59
Business Activities Loans \| Total Commercial Real Estate \| Other commercial real estate
Recorded Investment
With no related allowance:	5,933	5,896
With an allowance recorded:	1,142	1,071
Unpaid Principal Balance
With no related allowance:	5,944	5,903
With an allowance recorded:	1,204	1,132
Related Allowance
With an allowance recorded:	433	388
Business Activities Loans \| Commercial and industrial
Recorded Investment
Total	1,504	626
Unpaid Principal Balance
Total	1,510	625
Related Allowance
With an allowance recorded:	132	3
Business Activities Loans \| Commercial and industrial \| Other Commercial
Recorded Investment
With no related allowance:	962	218
With an allowance recorded:	542	408
Unpaid Principal Balance
With no related allowance:	966	217
With an allowance recorded:	544	408
Related Allowance
With an allowance recorded:	132	3
Business Activities Loans \| Commercial and industrial \| Agricultural
Recorded Investment
With no related allowance:	0	0
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	0	0
With an allowance recorded:	0	0
Related Allowance
With an allowance recorded:	0	0
Business Activities Loans \| Commercial and industrial \| Tax exempt
Recorded Investment
With no related allowance:	0	0
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	0	0
With an allowance recorded:	0	0
Related Allowance
With an allowance recorded:	0	0
Business Activities Loans \| Residential Real Estate
Recorded Investment
Total	4,386	1,404
Unpaid Principal Balance
Total	4,404	1,417
Related Allowance
With an allowance recorded:	84	9
Business Activities Loans \| Residential Real Estate \| Residential mortgages
Recorded Investment
With no related allowance:	3,586	1,247
With an allowance recorded:	800	157
Unpaid Principal Balance
With no related allowance:	3,603	1,260
With an allowance recorded:	801	157
Related Allowance
With an allowance recorded:	84	9
Business Activities Loans \| Consumer
Recorded Investment
Total	362	13
Unpaid Principal Balance
Total	463	13
Related Allowance
With an allowance recorded:	0	0
Business Activities Loans \| Consumer \| Home equity
Recorded Investment
With no related allowance:	362	13
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	463	13
With an allowance recorded:	0	0
Related Allowance
With an allowance recorded:	0	0
Business Activities Loans \| Consumer \| Other consumer
Recorded Investment
With no related allowance:	0	0
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	0	0
With an allowance recorded:	0	0
Related Allowance
With an allowance recorded:	0	0
Acquired Loans
Recorded Investment
Total	1,234	1,146
Unpaid Principal Balance
Total	1,363	1,370
Related Allowance
With an allowance recorded:	121	0
Acquired Loans \| Total Commercial Real Estate
Recorded Investment
Total	133	241
Unpaid Principal Balance
Total	245	352
Related Allowance
With an allowance recorded:	0	0
Acquired Loans \| Total Commercial Real Estate \| Construction and land development
Recorded Investment
With no related allowance:	0	0
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	0	0
With an allowance recorded:	0	0
Related Allowance
With an allowance recorded:	0	0
Acquired Loans \| Total Commercial Real Estate \| Other commercial real estate
Recorded Investment
With no related allowance:	133	241
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	245	352
With an allowance recorded:	0	0
Related Allowance
With an allowance recorded:	0	0
Acquired Loans \| Commercial and industrial
Recorded Investment
Total	598	571
Unpaid Principal Balance
Total	611	584
Related Allowance
With an allowance recorded:	121	0
Acquired Loans \| Commercial and industrial \| Other Commercial
Recorded Investment
With no related allowance:	176	571
With an allowance recorded:	422	0
Unpaid Principal Balance
With no related allowance:	175	584
With an allowance recorded:	436	0
Related Allowance
With an allowance recorded:	121	0
Acquired Loans \| Commercial and industrial \| Agricultural
Recorded Investment
With no related allowance:	0	0
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	0	0
With an allowance recorded:	0	0
Related Allowance
With an allowance recorded:	0	0
Acquired Loans \| Commercial and industrial \| Tax exempt
Recorded Investment
With no related allowance:	0	0
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	0	0
With an allowance recorded:	0	0
Related Allowance
With an allowance recorded:	0	0
Acquired Loans \| Residential Real Estate
Recorded Investment
Total	503	271
Unpaid Principal Balance
Total	507	278
Related Allowance
With an allowance recorded:	0	0
Acquired Loans \| Residential Real Estate \| Residential mortgages
Recorded Investment
With no related allowance:	503	271
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	507	278
With an allowance recorded:	0	0
Related Allowance
With an allowance recorded:	0	0
Acquired Loans \| Consumer
Recorded Investment
Total	0	63
Unpaid Principal Balance
Total	0	156
Related Allowance
With an allowance recorded:	0	0
Acquired Loans \| Consumer \| Home equity
Recorded Investment
With no related allowance:	0	63
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	0	156
With an allowance recorded:	0	0
Related Allowance
With an allowance recorded:	0	0
Acquired Loans \| Consumer \| Other consumer
Recorded Investment
With no related allowance:	0	0
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	0	0
With an allowance recorded:	0	0
Related Allowance
With an allowance recorded:	$ 0	$ 0

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