Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details) - Ratios of Allowance for Loan Losses		9 Months Ended		12 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Ratios of Allowance for Loan Losses [Abstract]
Ratio of allowance for loan losses to the end of period loans, net of unearned income and deferred fees		1.30%	1.35%	1.36%
Ratio of net charge-offs to average loans, net of unearned income and deferred fees(1)	[1]	0.19%	0.31%	0.27%

[1] Net charge-offs are on an annualized basis.