Note 8 - Loans - Average Balance and Interest Income Recognized Related to Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Average Recorded Investment	$ 127,259	$ 133,221	$ 127,722	$ 134,519
Interest Income Recognized	1,264	1,160	2,349	3,209
Commercial Portfolio Segment [Member]
Average Recorded Investment	24,987	28,091	22,572	18,602
Interest Income Recognized	678	170	760	488
Real Estate Construction Portfolio Segment [Member]
Average Recorded Investment	29,780	5,869	29,868	12,005
Interest Income Recognized	99	66	287	196
Commercial Real Estate Portfolio Segment [Member]
Average Recorded Investment	58,555	81,005	60,074	86,456
Interest Income Recognized	391	776	1,015	2,124
Residential Mortgage and Equity Lines Portfolio Segment [Member]
Average Recorded Investment	13,937	18,256	15,208	17,456
Interest Income Recognized	$ 96	$ 148	$ 287	$ 401