Note 11 - Fair Value Measurements (Details) - Fair Value Estimates for Financial Instruments, Excluding Financial Instruments Recorded at Fair Value on a Recurring Basis (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities held to maturity	$ 1,112,676	$ 1,184,557
Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	472,028	491,382
Investment securities held to maturity	1,597	3,275
Financial Liabilities:
Federal Home Loan Bank advances	20,558	26,150
Fair Value, Inputs, Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities held to maturity	1,111,079	1,181,282
Financial Liabilities:
Deposits	3,671,014	3,589,921
Short-term borrowed funds	62,668	53,687
Term repurchase agreement	10,054	10,135
Debt financing		15,645
Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	1,800,625	2,090,712
Other assets - FDIC indemnification receivable	4,032	13,834
Financial Liabilities:
Deposits	491,921	642,318
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	472,028	491,382
Investment securities held to maturity	1,132,299	1,156,041
Loans	1,796,051	2,081,123
Other assets - FDIC indemnification receivable	4,032	13,847
Financial Liabilities:
Deposits	4,163,781	4,232,492
Short-term borrowed funds	62,668	53,687
Federal Home Loan Bank advances	20,577	25,799
Term repurchase agreement	10,000	10,000
Debt financing		15,000
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	472,028	491,382
Investment securities held to maturity	1,112,676	1,184,557
Loans	1,800,625	2,090,712
Other assets - FDIC indemnification receivable	4,032	13,834
Financial Liabilities:
Deposits	4,162,935	4,232,239
Short-term borrowed funds	62,668	53,687
Federal Home Loan Bank advances	20,558	26,150
Term repurchase agreement	10,054	10,135
Debt financing		$ 15,645