Note 8 - Loans and Allowance for Loan Losses - Risk Category of Consumer Loans by Class (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Loans, net of unearned income	$ 1,035,469	$ 1,035,263
Consumer Portfolio Segment [Member]
Loans, net of unearned income	7,557	7,915
Consumer Portfolio Segment [Member] | Consumer Secured [Member]
Loans, net of unearned income	3,980	4,853
Consumer Portfolio Segment [Member] | Consumer Unsecured [Member]
Loans, net of unearned income	3,577	3,062
Performing Financial Instruments [Member] | Consumer Portfolio Segment [Member] | Consumer Secured [Member]
Loans, net of unearned income	3,980	4,853
Performing Financial Instruments [Member] | Consumer Portfolio Segment [Member] | Consumer Unsecured [Member]
Loans, net of unearned income	3,286	2,766
Nonperforming Financial Instruments [Member] | Consumer Portfolio Segment [Member] | Consumer Secured [Member]
Loans, net of unearned income	0
Nonperforming Financial Instruments [Member] | Consumer Portfolio Segment [Member] | Consumer Unsecured [Member]
Loans, net of unearned income	$ 291	$ 296