LOANS, Non-accrual and Past Due Loans (Details) $ in Thousands	Mar. 31, 2017 USD ($) Loan	Dec. 31, 2016 USD ($) Loan	Mar. 31, 2016 USD ($)
Non-accrual and Past Due Loans [Abstract]
Current & accruing	$ 657,135	$ 672,621
Nonaccrual	6,182	6,297
Total	663,923	679,563	$ 626,107
Commitments to lend additional funds to borrowers whose loans were on non-accrual status	0
30-59 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	606	484
60-89 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	0	161
90 Days or More Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	$ 0	$ 0
Commercial [Member]
Non-accrual and Past Due Loans [Abstract]
Number of nonaccrual loans | Loan	1	1
Current & accruing	$ 115,988	$ 121,311
Nonaccrual	5,000	5,000
Total	121,053	126,311	130,414
Commercial [Member] | 30-59 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	65	0
Commercial [Member] | 60-89 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	0	0
Commercial [Member] | 90 Days or More Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	$ 0	$ 0
Commercial Real Estate [Member]
Non-accrual and Past Due Loans [Abstract]
Number of nonaccrual loans | Loan	2	2
Current & accruing	$ 341,188	$ 343,186
Nonaccrual	514	540
Total	342,180	344,210	316,950
Commercial Real Estate [Member] | 30-59 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	478	484
Commercial Real Estate [Member] | 60-89 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	0	0
Commercial Real Estate [Member] | 90 Days or More Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	0	0
Agriculture [Member]
Non-accrual and Past Due Loans [Abstract]
Current & accruing	94,652	101,905
Nonaccrual	0	0
Total	94,652	101,905	77,185
Agriculture [Member] | 30-59 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	0	0
Agriculture [Member] | 60-89 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	0	0
Agriculture [Member] | 90 Days or More Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	$ 0	$ 0
Residential Mortgage [Member]
Non-accrual and Past Due Loans [Abstract]
Number of nonaccrual loans | Loan	3	3
Current & accruing	$ 42,508	$ 39,463
Nonaccrual	668	654
Total	43,176	40,237	41,412
Residential Mortgage [Member] | 30-59 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	0	0
Residential Mortgage [Member] | 60-89 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	0	120
Residential Mortgage [Member] | 90 Days or More Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	0	0
Residential Construction [Member]
Non-accrual and Past Due Loans [Abstract]
Current & accruing	22,738	23,650
Nonaccrual	0	0
Total	22,738	23,650	16,760
Residential Construction [Member] | 30-59 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	0	0
Residential Construction [Member] | 60-89 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	0	0
Residential Construction [Member] | 90 Days or More Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	0	$ 0
Consumer [Member]
Non-accrual and Past Due Loans [Abstract]
Number of nonaccrual loans | Loan		1
Current & accruing	40,061	$ 43,106
Nonaccrual	0	103
Total	40,124	43,250	$ 43,386
Consumer [Member] | 30-59 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	63	0
Consumer [Member] | 60-89 Days Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	0	41
Consumer [Member] | 90 Days or More Past Due [Member]
Non-accrual and Past Due Loans [Abstract]
Past due & accruing	$ 0	$ 0