Note 18 - Fair Value Measurements (Details) - Estimated Fair Values and Related Carrying Amounts of Financial Instruments (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Financial assets:
Financial Assets, Carrying Amount	$ 3,421,769	$ 3,527,489
Financial liabilities:
Financial Liabilities, Carrying Amount	3,019,919	3,121,427
Non-Interest Bearing Transaction Accounts [Member] | Fair Value, Inputs, Level 2 [Member]
Financial liabilities:
Financial Liabilities, Fair Value Measurement	565,433	576,655
Non-Interest Bearing Transaction Accounts [Member]
Financial liabilities:
Financial Liabilities, Carrying Amount	565,433	576,655
Financial Liabilities, Fair Value Measurement	565,433	576,655
Interest Bearing Transaction Accounts and Savings Deposits [Member] | Fair Value, Inputs, Level 2 [Member]
Financial liabilities:
Financial Liabilities, Fair Value Measurement	1,428,422	1,421,137
Interest Bearing Transaction Accounts and Savings Deposits [Member]
Financial liabilities:
Financial Liabilities, Carrying Amount	1,428,422	1,421,137
Financial Liabilities, Fair Value Measurement	1,428,422	1,421,137
Time Deposits [Member] | Fair Value, Inputs, Level 3 [Member]
Financial liabilities:
Financial Liabilities, Fair Value Measurement	823,059	880,201
Time Deposits [Member]
Financial liabilities:
Financial Liabilities, Carrying Amount	819,264	876,371
Financial Liabilities, Fair Value Measurement	823,059	880,201
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Member] | Fair Value, Inputs, Level 2 [Member]
Financial liabilities:
Financial Liabilities, Fair Value Measurement	79,063	104,078
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Member]
Financial liabilities:
Financial Liabilities, Carrying Amount	79,063	104,078
Financial Liabilities, Fair Value Measurement	79,063	104,078
Other Borrowings [Member] | Fair Value, Inputs, Level 2 [Member]
Financial liabilities:
Financial Liabilities, Fair Value Measurement	79,896	94,472
Other Borrowings [Member]
Financial liabilities:
Financial Liabilities, Carrying Amount	77,659	89,441
Financial Liabilities, Fair Value Measurement	79,896	94,472
Subordinated Debentures [Member] | Fair Value, Inputs, Level 2 [Member]
Financial liabilities:
Financial Liabilities, Fair Value Measurement	18,327	15,414
Subordinated Debentures [Member]
Financial liabilities:
Financial Liabilities, Carrying Amount	20,620	20,620
Financial Liabilities, Fair Value Measurement	18,327	15,414
Interet Payable [Member] | Fair Value, Inputs, Level 2 [Member]
Financial liabilities:
Financial Liabilities, Fair Value Measurement	1,130	1,096
Interet Payable [Member]
Financial liabilities:
Financial Liabilities, Carrying Amount	1,130	1,096
Financial Liabilities, Fair Value Measurement	1,130	1,096
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member]
Financial assets:
Financial Assets, Fair Value Measurement	459,234	537,797
Cash and Cash Equivalents [Member]
Financial assets:
Financial Assets, Carrying Amount	459,234	537,797
Financial Assets, Fair Value Measurement	459,234	537,797
Held-to-Maturity Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Financial assets:
Financial Assets, Fair Value Measurement	543,154	500,578
Held-to-Maturity Securities [Member]
Financial assets:
Financial Assets, Carrying Amount	555,464	496,141
Financial Assets, Fair Value Measurement	543,154	500,578
Mortgage Loans Held For Sale [Member] | Fair Value, Inputs, Level 3 [Member]
Financial assets:
Financial Assets, Fair Value Measurement	14,454	25,367
Mortgage Loans Held For Sale [Member]
Financial assets:
Financial Assets, Carrying Amount	14,454	25,367
Financial Assets, Fair Value Measurement	14,454	25,367
Interest Receivable [Member] | Fair Value, Inputs, Level 2 [Member]
Financial assets:
Financial Assets, Fair Value Measurement	12,637	14,530
Interest Receivable [Member]
Financial assets:
Financial Assets, Carrying Amount	12,637	14,530
Financial Assets, Fair Value Measurement	12,637	14,530
Loans1 [Member] | Fair Value, Inputs, Level 3 [Member]
Financial assets:
Financial Assets, Fair Value Measurement	1,622,698	1,602,014
Loans1 [Member]
Financial assets:
Financial Assets, Carrying Amount	1,622,997	1,600,631
Financial Assets, Fair Value Measurement	1,622,698	1,602,014
Loans Acquired, Covered By FDIC Loss Share [Member] | Fair Value, Inputs, Level 3 [Member]
Financial assets:
Financial Assets, Fair Value Measurement	160,693	208,685
Loans Acquired, Covered By FDIC Loss Share [Member]
Financial assets:
Financial Assets, Carrying Amount	163,736	210,842
Financial Assets, Fair Value Measurement	160,693	208,685
Loans Acquired, Not Covered By FDIC Loss Share [Member] | Fair Value, Inputs, Level 3 [Member]
Financial assets:
Financial Assets, Fair Value Measurement	61,619	82,764
Loans Acquired, Not Covered By FDIC Loss Share [Member]
Financial assets:
Financial Assets, Carrying Amount	63,500	82,764
Financial Assets, Fair Value Measurement	61,619	82,764
FDIC Indemnification Asset [Member] | Fair Value, Inputs, Level 3 [Member]
Financial assets:
Financial Assets, Fair Value Measurement	66,858	75,286
FDIC Indemnification Asset [Member]
Financial assets:
Financial Assets, Carrying Amount	66,858	75,286
Financial Assets, Fair Value Measurement	$ 66,858	$ 75,286