Note 6 - Mortgage Loan Servicing (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Continuing Involvement with Transferred Financial Assets Custodial Escrow Balance	$ 4,600	$ 3,000
Servicing Asset at Fair Value, Amount	$ 8,000	$ 7,800
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Discount Rate	7.01%	7.10%
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Prepayment Speed	11.50%	11.70%
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Expected Credit Losses	0.68%	0.90%
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Weighted Average Life	3 years 219 days	3 years 219 days
Valuation Allowance for Impairment of Recognized Servicing Assets, Balance	$ 0	$ 0