LOANS - Non-accrual Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Non-accrual loans
Total loans	$ 10,056	$ 11,550
Business Activities Loans
Non-accrual loans
Total loans	8,384	8,354
Acquired Loans
Non-accrual loans
Total loans	1,672	3,196
Total commercial loans
Non-accrual loans
Total loans	4,223	5,325
Total commercial loans | Business Activities Loans
Non-accrual loans
Total loans	3,847	4,356
Total commercial loans | Acquired Loans
Non-accrual loans
Total loans	376	969
Total commercial real estate
Non-accrual loans
Total loans	2,227	3,489
Total commercial real estate | Business Activities Loans
Non-accrual loans
Total loans	1,940	3,146
Total commercial real estate | Acquired Loans
Non-accrual loans
Total loans	287	343
Total commercial real estate | Construction and land development
Non-accrual loans
Total loans	276	258
Total commercial real estate | Construction and land development | Business Activities Loans
Non-accrual loans
Total loans	276	258
Total commercial real estate | Construction and land development | Acquired Loans
Non-accrual loans
Total loans	0	0
Total commercial real estate | Other commercial real estate
Non-accrual loans
Total loans	1,951	3,231
Total commercial real estate | Other commercial real estate | Business Activities Loans
Non-accrual loans
Total loans	1,664	2,888
Total commercial real estate | Other commercial real estate | Acquired Loans
Non-accrual loans
Total loans	287	343
Commercial and industrial
Non-accrual loans
Total loans	1,996	1,836
Commercial and industrial | Business Activities Loans
Non-accrual loans
Total loans	1,907	1,210
Commercial and industrial | Acquired Loans
Non-accrual loans
Total loans	89	626
Commercial and industrial | Commercial
Non-accrual loans
Total loans	1,371	1,558
Commercial and industrial | Commercial | Business Activities Loans
Non-accrual loans
Total loans	1,282	932
Commercial and industrial | Commercial | Acquired Loans
Non-accrual loans
Total loans	89	626
Commercial and industrial | Agricultural
Non-accrual loans
Total loans	625	278
Commercial and industrial | Agricultural | Business Activities Loans
Non-accrual loans
Total loans	625	278
Commercial and industrial | Agricultural | Acquired Loans
Non-accrual loans
Total loans	0	0
Commercial and industrial | Tax exempt
Non-accrual loans
Total loans	0	0
Commercial and industrial | Tax exempt | Business Activities Loans
Non-accrual loans
Total loans	0	0
Commercial and industrial | Tax exempt | Acquired Loans
Non-accrual loans
Total loans	0	0
Residential real estate
Non-accrual loans
Total loans	5,089	5,335
Residential real estate | Business Activities Loans
Non-accrual loans
Total loans	4,077	3,362
Residential real estate | Acquired Loans
Non-accrual loans
Total loans	1,012	1,973
Residential real estate | Residential mortgages
Non-accrual loans
Total loans	5,089	5,335
Residential real estate | Residential mortgages | Business Activities Loans
Non-accrual loans
Total loans	4,077	3,362
Residential real estate | Residential mortgages | Acquired Loans
Non-accrual loans
Total loans	1,012	1,973
Consumer
Non-accrual loans
Total loans	744	890
Consumer | Business Activities Loans
Non-accrual loans
Total loans	460	636
Consumer | Acquired Loans
Non-accrual loans
Total loans	284	254
Consumer | Home equity
Non-accrual loans
Total loans	724	869
Consumer | Home equity | Business Activities Loans
Non-accrual loans
Total loans	440	615
Consumer | Home equity | Acquired Loans
Non-accrual loans
Total loans	284	254
Consumer | Other consumer
Non-accrual loans
Total loans	20	21
Consumer | Other consumer | Business Activities Loans
Non-accrual loans
Total loans	20	21
Consumer | Other consumer | Acquired Loans
Non-accrual loans
Total loans	$ 0	$ 0