LOANS - Contractual Aging of Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
LOANS
Loans current and past due less than 30 days	$ 1,596,897	$ 1,627,899
Loans receivable	1,614,587	1,644,209
Past Due 30-89 Days
LOANS
Loans past due	8,754	8,607
Past Due 90+ Days
LOANS
Loans past due	8,936	7,703
Commercial
LOANS
Loans current and past due less than 30 days	990,295	1,002,260
Loans receivable	997,437	1,007,751
Commercial \| Past Due 30-89 Days
LOANS
Loans past due	1,100	2,453
Commercial \| Past Due 90+ Days
LOANS
Loans past due	6,042	3,038
Commercial \| Real estate loan
LOANS
Loans current and past due less than 30 days	519,474	529,998
Loans receivable	524,886	531,810
Commercial \| Real estate loan \| Past Due 30-89 Days
LOANS
Loans past due	630	66
Commercial \| Real estate loan \| Past Due 90+ Days
LOANS
Loans past due	4,782	1,746
Commercial \| Commercial and industrial
LOANS
Loans current and past due less than 30 days	154,745	158,523
Loans receivable	155,828	159,577
Commercial \| Commercial and industrial \| Past Due 30-89 Days
LOANS
Loans past due	94	55
Commercial \| Commercial and industrial \| Past Due 90+ Days
LOANS
Loans past due	989	999
Commercial \| Paycheck Protection Program - 1st Draw
LOANS
Loans current and past due less than 30 days	71,708	132,269
Loans receivable	71,708	132,269
Commercial \| Paycheck Protection Program - 1st Draw \| Past Due 30-89 Days
LOANS
Loans past due	0	0
Commercial \| Paycheck Protection Program - 1st Draw \| Past Due 90+ Days
LOANS
Loans past due	0	0
Commercial \| Paycheck Protection Program - 2nd Draw
LOANS
Loans current and past due less than 30 days	66,127	0
Loans receivable	66,127	0
Commercial \| Paycheck Protection Program - 2nd Draw \| Past Due 30-89 Days
LOANS
Loans past due	0	0
Commercial \| Paycheck Protection Program - 2nd Draw \| Past Due 90+ Days
LOANS
Loans past due	0	0
Commercial \| Political subdivisions
LOANS
Loans current and past due less than 30 days	49,860	53,221
Loans receivable	49,860	53,221
Commercial \| Political subdivisions \| Past Due 30-89 Days
LOANS
Loans past due	0	0
Commercial \| Political subdivisions \| Past Due 90+ Days
LOANS
Loans past due	0	0
Commercial \| Construction Loans
LOANS
Loans current and past due less than 30 days	45,060	42,590
Loans receivable	45,307	42,874
Commercial \| Construction Loans \| Past Due 30-89 Days
LOANS
Loans past due	198	284
Commercial \| Construction Loans \| Past Due 90+ Days
LOANS
Loans past due	49	0
Commercial \| Loans secured by farm land
LOANS
Loans current and past due less than 30 days	10,593	11,419
Loans receivable	10,897	11,736
Commercial \| Loans secured by farm land \| Past Due 30-89 Days
LOANS
Loans past due	82	95
Commercial \| Loans secured by farm land \| Past Due 90+ Days
LOANS
Loans past due	222	222
Commercial \| Multi-family (5 or more) residential
LOANS
Loans current and past due less than 30 days	54,049	53,860
Loans receivable	54,049	55,811
Commercial \| Multi-family (5 or more) residential \| Past Due 30-89 Days
LOANS
Loans past due	0	1,951
Commercial \| Multi-family (5 or more) residential \| Past Due 90+ Days
LOANS
Loans past due	0	0
Commercial \| Agricultural loans
LOANS
Loans current and past due less than 30 days	2,364	3,091
Loans receivable	2,460	3,164
Commercial \| Agricultural loans \| Past Due 30-89 Days
LOANS
Loans past due	96	2
Commercial \| Agricultural loans \| Past Due 90+ Days
LOANS
Loans past due	0	71
Commercial \| Other commercial loans
LOANS
Loans current and past due less than 30 days	16,315	17,289
Loans receivable	16,315	17,289
Commercial \| Other commercial loans \| Past Due 30-89 Days
LOANS
Loans past due	0	0
Commercial \| Other commercial loans \| Past Due 90+ Days
LOANS
Loans past due	0	0
Residential mortgage
LOANS
Loans current and past due less than 30 days	590,850	609,576
Loans receivable	601,253	620,172
Residential mortgage \| Past Due 30-89 Days
LOANS
Loans past due	7,628	6,071
Residential mortgage \| Past Due 90+ Days
LOANS
Loans past due	2,775	4,525
Residential mortgage \| Real estate loan \| first liens
LOANS
Loans current and past due less than 30 days	508,818	523,191
Loans receivable	518,392	532,947
Residential mortgage \| Real estate loan \| first liens \| Past Due 30-89 Days
LOANS
Loans past due	7,176	5,703
Residential mortgage \| Real estate loan \| first liens \| Past Due 90+ Days
LOANS
Loans past due	2,398	4,053
Residential mortgage \| Real estate loan \| junior liens
LOANS
Loans current and past due less than 30 days	25,201	27,009
Loans receivable	25,402	27,311
Residential mortgage \| Real estate loan \| junior liens \| Past Due 30-89 Days
LOANS
Loans past due	20	111
Residential mortgage \| Real estate loan \| junior liens \| Past Due 90+ Days
LOANS
Loans past due	181	191
Residential mortgage \| Construction Loans
LOANS
Loans current and past due less than 30 days	18,376	20,457
Loans receivable	18,376	20,613
Residential mortgage \| Construction Loans \| Past Due 30-89 Days
LOANS
Loans past due	0	156
Residential mortgage \| Construction Loans \| Past Due 90+ Days
LOANS
Loans past due	0	0
Residential mortgage \| Home equity lines of credit
LOANS
Loans current and past due less than 30 days	38,455	38,919
Loans receivable	39,083	39,301
Residential mortgage \| Home equity lines of credit \| Past Due 30-89 Days
LOANS
Loans past due	432	101
Residential mortgage \| Home equity lines of credit \| Past Due 90+ Days
LOANS
Loans past due	196	281
Consumer
LOANS
Loans current and past due less than 30 days	15,752	16,063
Loans receivable	15,897	16,286
Consumer \| Past Due 30-89 Days
LOANS
Loans past due	26	83
Consumer \| Past Due 90+ Days
LOANS
Loans past due	$ 119	$ 140