ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY (Credit Quality Indicators) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	$ 3,845,668	$ 3,818,459
Other commercial loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	116,507	123,922
Other Consumer Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	73,100	74,194
Commercial and industrial loans:
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	1,484,933	1,418,627
Commercial and industrial loans: | Working Capital Lines of Credit Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	778,853	743,675
Commercial and industrial loans: | Non-working capital loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	706,080	674,952
Commercial Real Estate and Multi-family Residential Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	1,480,008	1,443,021
Commercial Real Estate and Multi-family Residential Loans [Member] | Construction and land development loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	236,941	223,713
Commercial Real Estate and Multi-family Residential Loans [Member] | Owner Occupied Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	542,861	538,268
Commercial Real Estate and Multi-family Residential Loans [Member] | Nonowner Occupied Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	506,631	507,696
Commercial Real Estate and Multi-family Residential Loans [Member] | Multifamily Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	193,575	173,344
Agri-business and agricultural loans:
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	317,055	382,926
Agri-business and agricultural loans: | Loans Secured By Farmland [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	145,366	186,443
Agri-business and agricultural loans: | Loans For Agricultural Production [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	171,689	196,483
Consumer 1-4 Family Mortgage Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	374,065	375,769
Consumer 1-4 Family Mortgage Loans [Member] | Closed End First Mortgage Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	180,178	178,941
Consumer 1-4 Family Mortgage Loans [Member] | Open End And Junior Lien Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	180,579	183,381
Consumer 1-4 Family Mortgage Loans [Member] | Residential Construction and Land Development Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	13,308	13,447
Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	3,292,413	3,272,841
Pass [Member] | Other commercial loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	116,502	123,917
Pass [Member] | Other Consumer Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	14,282	18,642
Pass [Member] | Commercial and industrial loans: | Working Capital Lines of Credit Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	712,842	688,748
Pass [Member] | Commercial and industrial loans: | Non-working capital loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	654,352	624,275
Pass [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Construction and land development loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	235,676	222,445
Pass [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Owner Occupied Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	501,679	496,231
Pass [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Nonowner Occupied Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	504,275	505,033
Pass [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Multifamily Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	193,338	173,100
Pass [Member] | Agri-business and agricultural loans: | Loans Secured By Farmland [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	132,475	174,118
Pass [Member] | Agri-business and agricultural loans: | Loans For Agricultural Production [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	162,007	185,772
Pass [Member] | Consumer 1-4 Family Mortgage Loans [Member] | Closed End First Mortgage Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	55,130	52,301
Pass [Member] | Consumer 1-4 Family Mortgage Loans [Member] | Open End And Junior Lien Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	9,855	8,259
Pass [Member] | Consumer 1-4 Family Mortgage Loans [Member] | Residential Construction and Land Development Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	102,837	93,228
Special Mention [Member] | Other commercial loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Special Mention [Member] | Other Consumer Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Special Mention [Member] | Commercial and industrial loans: | Working Capital Lines of Credit Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	42,204	33,337
Special Mention [Member] | Commercial and industrial loans: | Non-working capital loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	22,189	20,171
Special Mention [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Construction and land development loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	441	441
Special Mention [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Owner Occupied Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	19,028	19,361
Special Mention [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Nonowner Occupied Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	1,676	1,970
Special Mention [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Multifamily Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	237	244
Special Mention [Member] | Agri-business and agricultural loans: | Loans Secured By Farmland [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	8,580	7,988
Special Mention [Member] | Agri-business and agricultural loans: | Loans For Agricultural Production [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	8,482	9,716
Special Mention [Member] | Consumer 1-4 Family Mortgage Loans [Member] | Closed End First Mortgage Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Special Mention [Member] | Consumer 1-4 Family Mortgage Loans [Member] | Open End And Junior Lien Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Special Mention [Member] | Consumer 1-4 Family Mortgage Loans [Member] | Residential Construction and Land Development Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	79,236	78,518
Substandard [Member] | Other commercial loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Substandard [Member] | Other Consumer Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	49	50
Substandard [Member] | Commercial and industrial loans: | Working Capital Lines of Credit Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	23,510	21,350
Substandard [Member] | Commercial and industrial loans: | Non-working capital loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	24,707	25,834
Substandard [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Construction and land development loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	824	827
Substandard [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Owner Occupied Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	22,154	22,676
Substandard [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Nonowner Occupied Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	680	693
Substandard [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Multifamily Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Substandard [Member] | Agri-business and agricultural loans: | Loans Secured By Farmland [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	4,311	4,337
Substandard [Member] | Agri-business and agricultural loans: | Loans For Agricultural Production [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	1,200	995
Substandard [Member] | Consumer 1-4 Family Mortgage Loans [Member] | Closed End First Mortgage Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	1,551	1,520
Substandard [Member] | Consumer 1-4 Family Mortgage Loans [Member] | Open End And Junior Lien Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	250	236
Substandard [Member] | Consumer 1-4 Family Mortgage Loans [Member] | Residential Construction and Land Development Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Doubtful [Member] | Other commercial loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Doubtful [Member] | Other Consumer Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Doubtful [Member] | Commercial and industrial loans: | Working Capital Lines of Credit Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Doubtful [Member] | Commercial and industrial loans: | Non-working capital loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Doubtful [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Construction and land development loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Doubtful [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Owner Occupied Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Doubtful [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Nonowner Occupied Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Doubtful [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Multifamily Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Doubtful [Member] | Agri-business and agricultural loans: | Loans Secured By Farmland [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Doubtful [Member] | Agri-business and agricultural loans: | Loans For Agricultural Production [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Doubtful [Member] | Consumer 1-4 Family Mortgage Loans [Member] | Closed End First Mortgage Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Doubtful [Member] | Consumer 1-4 Family Mortgage Loans [Member] | Open End And Junior Lien Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Doubtful [Member] | Consumer 1-4 Family Mortgage Loans [Member] | Residential Construction and Land Development Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Not Rated [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	371,182	373,872
Not Rated [Member] | Other commercial loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	5	5
Not Rated [Member] | Other Consumer Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	58,769	55,502
Not Rated [Member] | Commercial and industrial loans: | Working Capital Lines of Credit Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	297	240
Not Rated [Member] | Commercial and industrial loans: | Non-working capital loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	4,832	4,672
Not Rated [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Construction and land development loans
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Not Rated [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Owner Occupied Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Not Rated [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Nonowner Occupied Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Not Rated [Member] | Commercial Real Estate and Multi-family Residential Loans [Member] | Multifamily Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Not Rated [Member] | Agri-business and agricultural loans: | Loans Secured By Farmland [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Not Rated [Member] | Agri-business and agricultural loans: | Loans For Agricultural Production [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	0	0
Not Rated [Member] | Consumer 1-4 Family Mortgage Loans [Member] | Closed End First Mortgage Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	123,497	125,120
Not Rated [Member] | Consumer 1-4 Family Mortgage Loans [Member] | Open End And Junior Lien Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	170,474	174,886
Not Rated [Member] | Consumer 1-4 Family Mortgage Loans [Member] | Residential Construction and Land Development Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total ending loans balance	$ 13,308	$ 13,447