LOANS - Summary of Impaired Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Business Activities Loans
Recorded Investment
Total	$ 13,855	$ 9,647
Unpaid Principal Balance
Total	14,124	11,653
Related Allowance
With an allowance recorded:	611	459
Business Activities Loans \| Commercial real estate:
Recorded Investment
Total	9,835	7,604
Unpaid Principal Balance
Total	9,962	9,598
Related Allowance
With an allowance recorded:	422	447
Business Activities Loans \| 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 \| Commercial real estate: \| Other commercial real estate
Recorded Investment
With no related allowance:	8,209	5,896
With an allowance recorded:	1,625	1,071
Unpaid Principal Balance
With no related allowance:	8,301	5,903
With an allowance recorded:	1,660	1,132
Related Allowance
With an allowance recorded:	421	388
Business Activities Loans \| Commercial and industrial:
Recorded Investment
Total	1,445	626
Unpaid Principal Balance
Total	1,524	625
Related Allowance
With an allowance recorded:	78	3
Business Activities Loans \| Commercial and industrial: \| Other Commercial
Recorded Investment
With no related allowance:	649	218
With an allowance recorded:	796	408
Unpaid Principal Balance
With no related allowance:	669	217
With an allowance recorded:	855	408
Related Allowance
With an allowance recorded:	78	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	2,562	1,404
Unpaid Principal Balance
Total	2,625	1,417
Related Allowance
With an allowance recorded:	111	9
Business Activities Loans \| Residential real estate: \| Residential mortgages
Recorded Investment
With no related allowance:	1,671	1,247
With an allowance recorded:	891	157
Unpaid Principal Balance
With no related allowance:	1,709	1,260
With an allowance recorded:	916	157
Related Allowance
With an allowance recorded:	111	9
Business Activities Loans \| Consumer:
Recorded Investment
Total	13	13
Unpaid Principal Balance
Total	13	13
Related Allowance
With an allowance recorded:	0	0
Business Activities Loans \| Consumer: \| Home equity
Recorded Investment
With no related allowance:	0	13
With an allowance recorded:	13	0
Unpaid Principal Balance
With no related allowance:	0	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	1,358	1,146
Unpaid Principal Balance
Total	1,600	1,370
Related Allowance
With an allowance recorded:	41	0
Acquired Loans \| Commercial real estate:
Recorded Investment
Total	188	241
Unpaid Principal Balance
Total	187	352
Related Allowance
With an allowance recorded:	0	0
Acquired Loans \| 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
Acquired Loans \| Commercial real estate: \| Other commercial real estate
Recorded Investment
With no related allowance:	188	241
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	187	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
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	744	271
Unpaid Principal Balance
Total	903	278
Related Allowance
With an allowance recorded:	41	0
Acquired Loans \| Residential real estate: \| Residential mortgages
Recorded Investment
With no related allowance:	375	271
With an allowance recorded:	369	0
Unpaid Principal Balance
With no related allowance:	524	278
With an allowance recorded:	379	0
Related Allowance
With an allowance recorded:	41	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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