LOANS (Total Loans Outstanding) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016	Jun. 30, 2017	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 3,636,431	$ 3,471,668
Percentage of Subtotal	100.00%	100.00%
Less: Allowance for loan losses	$ (45,497)	$ (43,718)	$ (44,563)	$ (42,853)	$ (43,247)	$ (43,610)
Net deferred loan fees	(1,179)	(741)
Loans, net	3,589,755	3,427,209
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 3,205,072	$ 3,062,526
Percentage of Total commercial loans	88.10%	88.20%
Other consumer loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 67,545	$ 61,308
Percentage of Total consumer loans	1.90%	1.80%
Consumer Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 431,359	$ 409,142
Percentage of Total consumer loans	11.90%	11.80%
Commercial and Industrial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Less: Allowance for loan losses	$ (19,927)	$ (20,272)	(20,219)	(20,320)	(20,935)	(21,564)
Commercial and Industrial Loans [Member] | Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 1,362,120	$ 1,268,490
Percentage of Total commercial loans	37.50%	36.50%
Commercial and Industrial Loans [Member] | Working Capital Lines Of Credit Loans [Member] | Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 703,953	$ 624,404
Percentage of Total commercial loans	19.40%	18.00%
Commercial and Industrial Loans [Member] | Non-working Capital Loans [Member] | Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 658,167	$ 644,086
Percentage of Total commercial loans	18.10%	18.50%
Commercial Real Estate and Multi-family Residential Loans [Member] | Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 1,410,214	$ 1,300,923
Percentage of Total commercial loans	38.80%	37.50%
Commercial Real Estate and Multi-family Residential Loans [Member] | Construction and Land Development Loans [Member] | Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 287,778	$ 245,182
Percentage of Total commercial loans	7.90%	7.10%
Commercial Real Estate and Multi-family Residential Loans [Member] | Owner Occupied Loans [Member] | Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 499,651	$ 469,705
Percentage of Total commercial loans	13.70%	13.50%
Commercial Real Estate and Multi-family Residential Loans [Member] | Nonowner Occupied Loans [Member] | Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 456,930	$ 458,404
Percentage of Total commercial loans	12.60%	13.20%
Commercial Real Estate and Multi-family Residential Loans [Member] | Multifamily Loans [Member] | Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 165,855	$ 127,632
Percentage of Total commercial loans	4.60%	3.70%
Agri-business and Agricultural Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Less: Allowance for loan losses	$ (4,302)	$ (3,532)	$ (3,870)	$ (3,108)	$ (3,047)	$ (2,445)
Agri-business and Agricultural Loans [Member] | Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 317,880	$ 394,843
Percentage of Total commercial loans	8.70%	11.40%
Agri-business and Agricultural Loans [Member] | Loans Secured By Farmland [Member] | Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 161,553	$ 172,633
Percentage of Total commercial loans	4.40%	5.00%
Agri-business and Agricultural Loans [Member] | Loans For Agricultural Production [Member] | Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 156,327	$ 222,210
Percentage of Total commercial loans	4.30%	6.40%
Other Commercial Loans [Member] | Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 114,858	$ 98,270
Percentage of Total commercial loans	3.10%	2.80%
Total Consumer 1 To 4 Family Mortgage Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 363,814	$ 347,834
Percentage of Total consumer loans	10.00%	10.00%
Total Consumer 1 To 4 Family Mortgage Loans [Member] | Closed End First Mortgage Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 171,946	$ 163,155
Percentage of Total consumer loans	4.70%	4.70%
Total Consumer 1 To 4 Family Mortgage Loans [Member] | Open End And Junior Lien Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 181,338	$ 169,664
Percentage of Total consumer loans	5.00%	4.90%
Total Consumer 1 To 4 Family Mortgage Loans [Member] | Residential Construction and Land Development Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Commercial And Consumer Loans	$ 10,530	$ 15,015
Percentage of Total consumer loans	0.30%	0.40%