LOANS - Summary of Impaired Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Business Activities Loans
Recorded Investment
Total	$ 13,273	$ 13,855
Unpaid Principal Balance
Total	13,654	14,124
Related Allowance
With an allowance recorded:	533	611
Business Activities Loans \| Total commercial real estate
Recorded Investment
Total	9,204	9,835
Unpaid Principal Balance
Total	9,347	9,962
Related Allowance
With an allowance recorded:	396	422
Business Activities Loans \| Total commercial real estate \| Construction and land development
Recorded Investment
With no related allowance:	0	0
With an allowance recorded:	1	1
Unpaid Principal Balance
With no related allowance:	0	0
With an allowance recorded:	1	1
Related Allowance
With an allowance recorded:	1	1
Business Activities Loans \| Total commercial real estate \| Other commercial real estate
Recorded Investment
With no related allowance:	8,222	8,209
With an allowance recorded:	981	1,625
Unpaid Principal Balance
With no related allowance:	8,346	8,301
With an allowance recorded:	1,000	1,660
Related Allowance
With an allowance recorded:	395	421
Business Activities Loans \| Commercial and industrial
Recorded Investment
Total	1,361	1,445
Unpaid Principal Balance
Total	1,439	1,524
Related Allowance
With an allowance recorded:	53	78
Business Activities Loans \| Commercial and industrial \| Commercial
Recorded Investment
With no related allowance:	589	649
With an allowance recorded:	772	796
Unpaid Principal Balance
With no related allowance:	603	669
With an allowance recorded:	836	855
Related Allowance
With an allowance recorded:	53	78
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	2,695	2,562
Unpaid Principal Balance
Total	2,855	2,625
Related Allowance
With an allowance recorded:	83	111
Business Activities Loans \| Residential Real Estate \| Residential mortgages
Recorded Investment
With no related allowance:	1,960	1,671
With an allowance recorded:	735	891
Unpaid Principal Balance
With no related allowance:	2,013	1,709
With an allowance recorded:	842	916
Related Allowance
With an allowance recorded:	83	111
Business Activities Loans \| Consumer
Recorded Investment
Total	13	13
Unpaid Principal Balance
Total	13	13
Related Allowance
With an allowance recorded:	1	0
Business Activities Loans \| Consumer \| Home equity
Recorded Investment
With no related allowance:	0	0
With an allowance recorded:	13	13
Unpaid Principal Balance
With no related allowance:	0	0
With an allowance recorded:	13	13
Related Allowance
With an allowance recorded:	1	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	1,322	1,358
Unpaid Principal Balance
Total	1,578	1,600
Related Allowance
With an allowance recorded:	38	41
Acquired Loans \| Total commercial real estate
Recorded Investment
Total	188	188
Unpaid Principal Balance
Total	187	187
Related Allowance
With an allowance recorded:	16	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:	90	188
With an allowance recorded:	98	0
Unpaid Principal Balance
With no related allowance:	90	187
With an allowance recorded:	97	0
Related Allowance
With an allowance recorded:	16	0
Acquired Loans \| Commercial and industrial
Recorded Investment
Total	405	426
Unpaid Principal Balance
Total	494	510
Related Allowance
With an allowance recorded:	0	0
Acquired Loans \| Commercial and industrial \| Commercial
Recorded Investment
With no related allowance:	405	426
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	494	510
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	729	744
Unpaid Principal Balance
Total	897	903
Related Allowance
With an allowance recorded:	22	41
Acquired Loans \| Residential Real Estate \| Residential mortgages
Recorded Investment
With no related allowance:	365	375
With an allowance recorded:	364	369
Unpaid Principal Balance
With no related allowance:	519	524
With an allowance recorded:	378	379
Related Allowance
With an allowance recorded:	22	41
Acquired Loans \| Consumer
Recorded Investment
Total	0	0
Unpaid Principal Balance
Total	0	0
Related Allowance
With an allowance recorded:	0	0
Acquired Loans \| Consumer \| Home equity
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 \| 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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