Note 8 - Deposits and Borrowed Funds (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Deposits	$ 4,161,950		$ 4,232,492
Demand Deposit, Overdrafts	2,942		6,307
Interest Expense, Time Deposits, $100,000 or More	304	423
Short-term Debt	61,854		53,687
Long-term Federal Home Loan Bank Advances	25,743		25,799
Federal Home Loan Bank, Advances, Maturities Summary, Due in Remainder of Fiscal Year	5,000
Federal Home Loan Bank, Advances, Maturities Summary, Due in Year Two	20,000
Securities Sold under Agreements to Repurchase	10,000		10,000
Line of Credit Facility, Maximum Borrowing Capacity	35,000
Debt Instrument, Interest Rate, Stated Percentage	2.00%
Unsecured Debt	15,000		15,000
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	5.31%
Short-term Debt [Member]
Pledged Financial Instruments, Not Separately Reported, Other Debt Securities Available-for-sale or Held-for-investment	112,182
Securities Sold Under Agreement To Repurchase [Member]
Pledged Financial Instruments, Not Separately Reported, Other Debt Securities Available-for-sale or Held-for-investment	14,621
Residential Real Estate Loans [Member]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	28,843
Securities [Member]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	$ 9,701