Note 18 - Fair Value Measurements (Details) - Estimated Fair Values and Related Carrying Amounts of Financial Instruments (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Financial assets:
Financial Assets, Carrying Amount	$ 3,441,709	$ 3,527,489
Financial liabilities:
Financial Liabilities, Carrying Amount	3,038,675	3,121,427
Non-Interest Bearing Transaction Accounts [Member] | Fair Value, Inputs, Level 2 [Member]
Financial liabilities:
Financial Liabilities, Fair Value Measurement	580,063	576,655
Non-Interest Bearing Transaction Accounts [Member]
Financial liabilities:
Financial Liabilities, Carrying Amount	580,063	576,655
Financial Liabilities, Fair Value Measurement	580,063	576,655
Interest Bearing Transaction Accounts and Savings Deposits [Member] | Fair Value, Inputs, Level 2 [Member]
Financial liabilities:
Financial Liabilities, Fair Value Measurement	1,453,139	1,421,137
Interest Bearing Transaction Accounts and Savings Deposits [Member]
Financial liabilities:
Financial Liabilities, Carrying Amount	1,453,139	1,421,137
Financial Liabilities, Fair Value Measurement	1,453,139	1,421,137
Time Deposits [Member] | Fair Value, Inputs, Level 3 [Member]
Financial liabilities:
Financial Liabilities, Fair Value Measurement	808,972	880,201
Time Deposits [Member]
Financial liabilities:
Financial Liabilities, Carrying Amount	805,596	876,371
Financial Liabilities, Fair Value Measurement	808,972	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	62,311	104,078
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Member]
Financial liabilities:
Financial Liabilities, Carrying Amount	62,311	104,078
Financial Liabilities, Fair Value Measurement	62,311	104,078
Other Borrowings [Member] | Fair Value, Inputs, Level 2 [Member]
Financial liabilities:
Financial Liabilities, Fair Value Measurement	77,594	94,472
Other Borrowings [Member]
Financial liabilities:
Financial Liabilities, Carrying Amount	75,987	89,441
Financial Liabilities, Fair Value Measurement	77,594	94,472
Subordinated Debentures [Member] | Fair Value, Inputs, Level 2 [Member]
Financial liabilities:
Financial Liabilities, Fair Value Measurement	13,165	15,414
Subordinated Debentures [Member]
Financial liabilities:
Financial Liabilities, Carrying Amount	20,620	20,620
Financial Liabilities, Fair Value Measurement	13,165	15,414
Interet Payable [Member] | Fair Value, Inputs, Level 2 [Member]
Financial liabilities:
Financial Liabilities, Fair Value Measurement	954	1,096
Interet Payable [Member]
Financial liabilities:
Financial Liabilities, Carrying Amount	954	1,096
Financial Liabilities, Fair Value Measurement	954	1,096
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member]
Financial assets:
Financial Assets, Fair Value Measurement	376,485	537,797
Cash and Cash Equivalents [Member]
Financial assets:
Financial Assets, Carrying Amount	376,485	537,797
Financial Assets, Fair Value Measurement	376,485	537,797
Held-to-Maturity Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Financial assets:
Financial Assets, Fair Value Measurement	570,703	500,578
Held-to-Maturity Securities [Member]
Financial assets:
Financial Assets, Carrying Amount	581,768	496,141
Financial Assets, Fair Value Measurement	570,703	500,578
Mortgage Loans Held For Sale [Member] | Fair Value, Inputs, Level 3 [Member]
Financial assets:
Financial Assets, Fair Value Measurement	10,605	25,367
Mortgage Loans Held For Sale [Member]
Financial assets:
Financial Assets, Carrying Amount	10,605	25,367
Financial Assets, Fair Value Measurement	10,605	25,367
Interest Receivable [Member] | Fair Value, Inputs, Level 2 [Member]
Financial assets:
Financial Assets, Fair Value Measurement	15,635	14,530
Interest Receivable [Member]
Financial assets:
Financial Assets, Carrying Amount	15,635	14,530
Financial Assets, Fair Value Measurement	15,635	14,530
Loans1 [Member] | Fair Value, Inputs, Level 3 [Member]
Financial assets:
Financial Assets, Fair Value Measurement	1,702,306	1,602,014
Loans1 [Member]
Financial assets:
Financial Assets, Carrying Amount	1,713,628	1,600,631
Financial Assets, Fair Value Measurement	1,702,306	1,602,014
Loans Acquired, Covered By FDIC Loss Share [Member] | Fair Value, Inputs, Level 3 [Member]
Financial assets:
Financial Assets, Fair Value Measurement	145,971	208,685
Loans Acquired, Covered By FDIC Loss Share [Member]
Financial assets:
Financial Assets, Carrying Amount	148,884	210,842
Financial Assets, Fair Value Measurement	145,971	208,685
Loans Acquired, Not Covered By FDIC Loss Share [Member] | Fair Value, Inputs, Level 3 [Member]
Financial assets:
Financial Assets, Fair Value Measurement	66,163	82,764
Loans Acquired, Not Covered By FDIC Loss Share [Member]
Financial assets:
Financial Assets, Carrying Amount	68,133	82,764
Financial Assets, Fair Value Measurement	66,163	82,764
FDIC Indemnification Asset [Member] | Fair Value, Inputs, Level 3 [Member]
Financial assets:
Financial Assets, Fair Value Measurement	61,500	75,286
FDIC Indemnification Asset [Member]
Financial assets:
Financial Assets, Carrying Amount	61,500	75,286
Financial Assets, Fair Value Measurement	$ 61,500	$ 75,286