LOANS - Summary of Impaired Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Business Activities Loans
Recorded Investment
Total	$ 7,950	$ 13,855
Unpaid Principal Balance
Total	8,408	14,124
Related Allowance
With an allowance recorded:	1,452	611
Business Activities Loans \| Commercial real estate:
Recorded Investment
Total	3,964	9,835
Unpaid Principal Balance
Total	4,155	9,962
Related Allowance
With an allowance recorded:	1,231	422
Business Activities Loans \| Commercial real estate: \| Construction and land development
Recorded Investment
With no related allowance:	0	0
With an allowance recorded:	258	1
Unpaid Principal Balance
With no related allowance:	0	0
With an allowance recorded:	258	1
Related Allowance
With an allowance recorded:	205	1
Business Activities Loans \| Commercial real estate: \| Other commercial real estate
Recorded Investment
With no related allowance:	1,911	8,209
With an allowance recorded:	1,795	1,625
Unpaid Principal Balance
With no related allowance:	1,957	8,301
With an allowance recorded:	1,940	1,660
Related Allowance
With an allowance recorded:	1,026	421
Business Activities Loans \| Commercial and industrial:
Recorded Investment
Total	1,353	1,445
Unpaid Principal Balance
Total	1,423	1,524
Related Allowance
With an allowance recorded:	164	78
Business Activities Loans \| Commercial and industrial: \| Commercial
Recorded Investment
With no related allowance:	710	649
With an allowance recorded:	282	796
Unpaid Principal Balance
With no related allowance:	773	669
With an allowance recorded:	289	855
Related Allowance
With an allowance recorded:	164	78
Business Activities Loans \| Commercial and industrial: \| Agricultural
Recorded Investment
With no related allowance:	361	0
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	361	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	2,620	2,562
Unpaid Principal Balance
Total	2,817	2,625
Related Allowance
With an allowance recorded:	57	111
Business Activities Loans \| Residential real estate: \| Residential mortgages
Recorded Investment
With no related allowance:	2,067	1,671
With an allowance recorded:	553	891
Unpaid Principal Balance
With no related allowance:	2,227	1,709
With an allowance recorded:	590	916
Related Allowance
With an allowance recorded:	57	111
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	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:	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	1,675	1,358
Unpaid Principal Balance
Total	2,053	1,600
Related Allowance
With an allowance recorded:	61	41
Acquired Loans \| Commercial real estate:
Recorded Investment
Total	258	188
Unpaid Principal Balance
Total	258	187
Related Allowance
With an allowance recorded:	12	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
With an allowance recorded:	0	0
Related Allowance
With an allowance recorded:	0	0
Acquired Loans \| Commercial real estate: \| Other commercial real estate
Recorded Investment
With no related allowance:	90	188
With an allowance recorded:	168	0
Unpaid Principal Balance
With no related allowance:	90	187
With an allowance recorded:	168	0
Related Allowance
With an allowance recorded:	12	0
Acquired Loans \| Commercial and industrial:
Recorded Investment
Total	385	426
Unpaid Principal Balance
Total	481	510
Related Allowance
With an allowance recorded:	0	0
Acquired Loans \| Commercial and industrial: \| Commercial
Recorded Investment
With no related allowance:	385	426
With an allowance recorded:	0
Unpaid Principal Balance
With no related allowance:	481	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	1,032	744
Unpaid Principal Balance
Total	1,314	903
Related Allowance
With an allowance recorded:	49	41
Acquired Loans \| Residential real estate: \| Residential mortgages
Recorded Investment
With no related allowance:	678	375
With an allowance recorded:	354	369
Unpaid Principal Balance
With no related allowance:	938	524
With an allowance recorded:	376	379
Related Allowance
With an allowance recorded:	49	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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