Note 9 - Fair Value Measurements (Detail) - Fair value estimates for financial instruments, excluding financial instruments recorded at fair value on a recurring basis (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Carrying (Reported) Amount, Fair Value Disclosure [Member]
Financial Assets
Cash and due from banks	$ 459,754	$ 338,793
Money market assets		392
Investment securities held to maturity	755,906	580,728
Loans	2,601,946	2,886,448
Other assets - FDIC receivable	38,812	44,738
Financial Liabilities
Deposits	4,192,383	4,132,961
Short-term borrowed funds	120,917	107,385
Federal Home Loan Bank advances	26,078	61,698
Debt financing and notes payable	15,000	26,363
Other liabilities - restricted performance share grants	1,546	2,259
Estimate of Fair Value, Fair Value Disclosure [Member]
Financial Assets
Cash and due from banks	459,754	338,793
Money market assets		392
Investment securities held to maturity	778,330	594,711
Loans	2,640,281	2,923,612
Other assets - FDIC receivable	38,733	44,353
Financial Liabilities
Deposits	4,192,443	4,135,113
Short-term borrowed funds	120,917	107,385
Federal Home Loan Bank advances	26,782	61,833
Debt financing and notes payable	15,337	26,811
Other liabilities - restricted performance share grants	$ 1,546	$ 2,259

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Company may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months.

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