LOANS - Summary of Impaired Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Business Activities Loans
Recorded Investment
Total	$ 15,551	$ 9,647
Unpaid Principal Balance
Total	16,042	11,653
Related Allowance
With an allowance recorded:	842	459
Business Activities Loans \| Total commercial real estate
Recorded Investment
Total	9,016	7,604
Unpaid Principal Balance
Total	9,126	9,598
Related Allowance
With an allowance recorded:	688	447
Business Activities Loans \| Total commercial real estate \| Construction and land development
Recorded Investment
With no related allowance:	0	0
With an allowance recorded:	1	637
Unpaid Principal Balance
With no related allowance:	0	0
With an allowance recorded:	1	2,563
Related Allowance
With an allowance recorded:	1	59
Business Activities Loans \| Total commercial real estate \| Other commercial real estate
Recorded Investment
With no related allowance:	6,776	5,896
With an allowance recorded:	2,239	1,071
Unpaid Principal Balance
With no related allowance:	6,787	5,903
With an allowance recorded:	2,338	1,132
Related Allowance
With an allowance recorded:	687	388
Business Activities Loans \| Commercial and industrial
Recorded Investment
Total	1,435	626
Unpaid Principal Balance
Total	1,465	625
Related Allowance
With an allowance recorded:	62	3
Business Activities Loans \| Commercial and industrial \| Other Commercial
Recorded Investment
With no related allowance:	634	218
With an allowance recorded:	801	408
Unpaid Principal Balance
With no related allowance:	649	217
With an allowance recorded:	816	408
Related Allowance
With an allowance recorded:	62	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	4,940	1,404
Unpaid Principal Balance
Total	4,988	1,417
Related Allowance
With an allowance recorded:	92	9
Business Activities Loans \| Residential Real Estate \| Residential mortgages
Recorded Investment
With no related allowance:	4,037	1,247
With an allowance recorded:	903	157
Unpaid Principal Balance
With no related allowance:	4,067	1,260
With an allowance recorded:	921	157
Related Allowance
With an allowance recorded:	92	9
Business Activities Loans \| Consumer
Recorded Investment
Total	160	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:	147	13
With an allowance recorded:	13	0
Unpaid Principal Balance
With no related allowance:	450	13
With an allowance recorded:	13	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	989	1,146
Unpaid Principal Balance
Total	1,079	1,370
Related Allowance
With an allowance recorded:	20	0
Acquired Loans \| Total commercial real estate
Recorded Investment
Total	98	241
Unpaid Principal Balance
Total	97	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:	98	241
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	97	352
With an allowance recorded:	0	0
Related Allowance
With an allowance recorded:	0	0
Acquired Loans \| Commercial and industrial
Recorded Investment
Total	426	571
Unpaid Principal Balance
Total	510	584
Related Allowance
With an allowance recorded:	0	0
Acquired Loans \| Commercial and industrial \| Other Commercial
Recorded Investment
With no related allowance:	426	571
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	510	584
With an allowance recorded:	0	0
Related Allowance
With an allowance recorded:	0	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	465	271
Unpaid Principal Balance
Total	472	278
Related Allowance
With an allowance recorded:	20	0
Acquired Loans \| Residential Real Estate \| Residential mortgages
Recorded Investment
With no related allowance:	281	271
With an allowance recorded:	184	0
Unpaid Principal Balance
With no related allowance:	283	278
With an allowance recorded:	189	0
Related Allowance
With an allowance recorded:	20	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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