Note 20 - Assets and Liabilities Measured and Reported at Fair Value - Assets Measured at Fair Value on a Non-recurring Basis (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Other real estate owned losses	$ 39	$ 409	$ (147)
Fair Value, Measurements, Nonrecurring [Member]
Impaired loans	2,569	2,933
Impaired loans losses	(121)	(1,470)
Other real estate owned	2,640	4,488
Other real estate owned losses	(171)	(62)
Total	5,209	7,421
Total losses	(292)	(1,532)
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Impaired loans	2,569	2,933
Other real estate owned	2,640	4,488
Total	$ 5,209	$ 7,421