Note 1 - Basis of Presentation (Detail) (USD $)	1 Months Ended		3 Months Ended	9 Months Ended
	Oct. 31, 2012	Sep. 30, 2012	Sep. 30, 2012 Stock Options [Member]	Sep. 30, 2012 Stock Options [Member]	Oct. 31, 2012 Loans and Other Real Estate [Member]	Oct. 31, 2012 Loans and Foreclosed Real Estate Covered By FDIC Loss Sharing Arrangement [Member]
Business Acquisition, Date of Acquisition Agreement	Oct. 19, 2012
Business Acquisition, Purchase Price Allocation, Assets Acquired	$ 184,100,000
Business Acquisition, Purchase Price Allocation, Noncurrent Assets					147,200,000	126,600,000
Business Acquisition, Purchase Price Allocation, Current Assets, Cash and Cash Equivalents	18,700,000
Business Acquisition, Purchase Price Allocation, Current Assets, Marketable Securities	8,600,000
Business Acquisition, Purchase Price Allocation, Liabilities Assumed	177,400,000
Business Acquisition, Purchase Price Allocation, Current Liabilities	168,600,000
Business Acquisition, FDIC Payment	13,800,000	10,500,000
FDIC Loss Coverage Percentage, Loans and Foreclosed Real Estate of Acquisition	80.00%
Business Acquisition, Discount On Assets Acquired	$ 21,000,000
Business Acquisition, FDIC Loss Sharing Arrangment, Description of Reimbursements For Recoveries	The Bank will reimburse the FDIC for 80% of its recoveries with respect to losses for which the FDIC paid the Bank 80% reimbursement under the loss sharing agreement.
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in Shares)			177,870	152,470