LOANS - Summary of Impaired Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Business Activities Loans
Recorded Investment
Total	$ 9,647	$ 6,709
Unpaid Principal Balance
Total	11,653	8,989
Related Allowance
With an allowance recorded:	459	424
Business Activities Loans \| Commercial Real Estate:
Recorded Investment
Total	7,604	4,481
Unpaid Principal Balance
Total	9,598	6,494
Related Allowance
With an allowance recorded:	447	193
Business Activities Loans \| Commercial Real Estate: \| Construction and land development
Recorded Investment
With no related allowance:	0	0
With an allowance recorded:	637	0
Unpaid Principal Balance
With no related allowance:	0	0
With an allowance recorded:	2,563	0
Related Allowance
With an allowance recorded:	59	0
Business Activities Loans \| Commercial Real Estate: \| Other commercial real estate
Recorded Investment
With no related allowance:	5,896	2,831
With an allowance recorded:	1,071	1,650
Unpaid Principal Balance
With no related allowance:	5,903	2,919
With an allowance recorded:	1,132	3,575
Related Allowance
With an allowance recorded:	388	193
Business Activities Loans \| Commercial and Industrial:
Recorded Investment
Total	626	486
Unpaid Principal Balance
Total	625	636
Related Allowance
With an allowance recorded:	3	173
Business Activities Loans \| Commercial and Industrial: \| Other Commercial
Recorded Investment
With no related allowance:	218	130
With an allowance recorded:	408	217
Unpaid Principal Balance
With no related allowance:	217	130
With an allowance recorded:	408	367
Related Allowance
With an allowance recorded:	3	173
Business Activities Loans \| Commercial and Industrial: \| Agricultural and other loans to farmers
Recorded Investment
With no related allowance:	0	139
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	0	139
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	1,404	1,709
Unpaid Principal Balance
Total	1,417	1,826
Related Allowance
With an allowance recorded:	9	49
Business Activities Loans \| Residential Real Estate: \| Residential mortgages
Recorded Investment
With no related allowance:	1,247	1,387
With an allowance recorded:	157	322
Unpaid Principal Balance
With no related allowance:	1,260	1,504
With an allowance recorded:	157	322
Related Allowance
With an allowance recorded:	9	49
Business Activities Loans \| Consumer:
Recorded Investment
Total	13	33
Unpaid Principal Balance
Total	13	33
Related Allowance
With an allowance recorded:	0	9
Business Activities Loans \| Consumer: \| Home equity
Recorded Investment
With no related allowance:	13	16
With an allowance recorded:	0	0
Unpaid Principal Balance
With no related allowance:	13	16
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	2
With an allowance recorded:	0	15
Unpaid Principal Balance
With no related allowance:	0	2
With an allowance recorded:	0	15
Related Allowance
With an allowance recorded:	0	$ 9
Acquired Loans
Recorded Investment
Total	1,146
Unpaid Principal Balance
Total	1,370
Related Allowance
With an allowance recorded:	0
Acquired Loans \| Commercial Real Estate:
Recorded Investment
Total	241
Unpaid Principal Balance
Total	352
Related Allowance
With an allowance recorded:	0
Acquired Loans \| Commercial Real Estate: \| Construction and land development
Recorded Investment
With no related allowance:	0
With an allowance recorded:	0
Unpaid Principal Balance
With no related allowance:	0
With an allowance recorded:	0
Related Allowance
With an allowance recorded:	0
Acquired Loans \| Commercial Real Estate: \| Other commercial real estate
Recorded Investment
With no related allowance:	241
With an allowance recorded:	0
Unpaid Principal Balance
With no related allowance:	352
With an allowance recorded:	0
Related Allowance
With an allowance recorded:	0
Acquired Loans \| Commercial and Industrial:
Recorded Investment
Total	571
Unpaid Principal Balance
Total	584
Related Allowance
With an allowance recorded:	0
Acquired Loans \| Commercial and Industrial: \| Other Commercial
Recorded Investment
With no related allowance:	571
With an allowance recorded:	0
Unpaid Principal Balance
With no related allowance:	584
With an allowance recorded:	0
Related Allowance
With an allowance recorded:	0
Acquired Loans \| Commercial and Industrial: \| Agricultural and other loans to farmers
Recorded Investment
With no related allowance:	0
With an allowance recorded:	0
Unpaid Principal Balance
With no related allowance:	0
With an allowance recorded:	0
Related Allowance
With an allowance recorded:	0
Acquired Loans \| Commercial and Industrial: \| Tax exempt
Recorded Investment
With no related allowance:	0
With an allowance recorded:	0
Unpaid Principal Balance
With no related allowance:	0
With an allowance recorded:	0
Related Allowance
With an allowance recorded:	0
Acquired Loans \| Residential Real Estate:
Recorded Investment
Total	271
Unpaid Principal Balance
Total	278
Related Allowance
With an allowance recorded:	0
Acquired Loans \| Residential Real Estate: \| Residential mortgages
Recorded Investment
With no related allowance:	271
With an allowance recorded:	0
Unpaid Principal Balance
With no related allowance:	278
With an allowance recorded:	0
Related Allowance
With an allowance recorded:	0
Acquired Loans \| Consumer:
Recorded Investment
Total	63
Unpaid Principal Balance
Total	156
Related Allowance
With an allowance recorded:	0
Acquired Loans \| Consumer: \| Home equity
Recorded Investment
With no related allowance:	63
With an allowance recorded:	0
Unpaid Principal Balance
With no related allowance:	156
With an allowance recorded:	0
Related Allowance
With an allowance recorded:	0
Acquired Loans \| Consumer: \| Other consumer
Recorded Investment
With no related allowance:	0
With an allowance recorded:	0
Unpaid Principal Balance
With no related allowance:	0
With an allowance recorded:	0
Related Allowance
With an allowance recorded:	$ 0

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