Note 7 - Accrued Interest Receivable - Accrued Interest Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Accrued interest receivable	$ 7,677	$ 7,006
Loans Receivable [Member]
Accrued interest receivable	6,053	5,846
Investment Securities [Member]
Accrued interest receivable	1,619	1,148
Deposits in Banks [Member]
Accrued interest receivable	$ 5	$ 12