LOANS (Total Loans Outstanding) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial loans	$ 1,944,127	$ 1,929,359
Total consumer loans	318,938	328,485
Subtotal	2,263,065	2,257,844
Less: Allowance for loan losses	(50,818)	(51,445)	(52,757)	(53,400)
Net deferred loan fees	(605)	(324)
Loans, net of allowance for loan losses of $51,445 and $53,400	2,211,642	2,206,075
Percentage of Total commercial loans	85.90%	85.50%
Percentage of Total consumer loans	14.10%	14.50%
Percentage of Subtotal	100.00%	100.00%
Commercial and Industrial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial loans	842,229	846,822
Less: Allowance for loan losses	(22,113)	(22,342)	(22,134)	(22,830)
Percentage of Total commercial loans	37.20%	37.50%
Commercial and Industrial Loans [Member] | Working Capital Lines Of Credit Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial loans	437,295	439,638
Percentage of Total commercial loans	19.30%	19.50%
Commercial and Industrial Loans [Member] | Non-working Capital Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial loans	404,934	407,184
Percentage of Total commercial loans	17.90%	18.00%
Commercial Real Estate and Multi-family Residential Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial loans	848,182	801,011
Percentage of Total commercial loans	37.50%	35.50%
Commercial Real Estate and Multi-family Residential Loans [Member] | Construction and Land Development Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial loans	97,263	82,494
Percentage of Total commercial loans	4.30%	3.70%
Commercial Real Estate and Multi-family Residential Loans [Member] | Owner Occupied Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial loans	365,619	358,617
Percentage of Total commercial loans	16.20%	15.90%
Commercial Real Estate and Multi-family Residential Loans [Member] | Nonowner Occupied Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial loans	339,030	314,889
Percentage of Total commercial loans	15.00%	13.90%
Commercial Real Estate and Multi-family Residential Loans [Member] | Multifamily Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial loans	46,270	45,011
Percentage of Total commercial loans	2.00%	2.00%
Agri-business and Agricultural Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial loans	204,849	224,719
Less: Allowance for loan losses	(1,263)	(1,403)	(538)	(695)
Percentage of Total commercial loans	9.10%	10.00%
Agri-business and Agricultural Loans [Member] | Loans Secured By Farmland [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial loans	99,537	109,147
Percentage of Total commercial loans	4.40%	4.80%
Agri-business and Agricultural Loans [Member] | Loans For Agricultural Production [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial loans	105,312	115,572
Percentage of Total commercial loans	4.70%	5.10%
Other Commerical Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial loans	48,867	56,807
Percentage of Total commercial loans	2.20%	2.50%
Consumer One To Four Family Mortgage Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total consumer loans	277,047	282,730
Percentage of Total consumer loans	12.20%	12.50%
Consumer One To Four Family Mortgage Loans [Member] | Closed End First Mortgage Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total consumer loans	116,164	109,823
Percentage of Total consumer loans	5.10%	4.90%
Consumer One To Four Family Mortgage Loans [Member] | Open End And Junior Lien Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total consumer loans	154,773	161,366
Percentage of Total consumer loans	6.80%	7.10%
Consumer One To Four Family Mortgage Loans [Member] | Residential Construction and Land Development Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total consumer loans	6,110	11,541
Percentage of Total consumer loans	0.30%	0.50%
Other Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total consumer loans	$ 41,891	$ 45,755
Percentage of Total consumer loans	1.90%	2.00%