Note 16 - Share Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Outstanding, Options (in shares)	165,886	390,334		532,926
Outstanding, weighted average exercise price per share (in dollars per share)	$ 17.98	$ 13.58		$ 11.03
Outstanding, weighted average contractual life (Year)	4 years 182 days	4 years 219 days		3 years 182 days	3 years 146 days
Outstanding, Intrinsic value					$ 66,130
Granted (in shares)	0	0		0
Exercised, Options (in shares)				(137,771)
Exercised, weighted average exercise price per share (in dollars per share)				$ 3.63
Forfeited / Expired, Options (in shares)	(20,085)	(224,448)		(4,821)
Forfeited / Expired, weighted average exercise price per share (in dollars per share)	$ 18.10	$ 10.33		$ 16.43
Exercised, Options (in shares)				137,771
Outstanding, Options (in shares)	145,801	165,886	165,886	390,334	532,926
Outstanding Options, weighted average exercise price per share (in dollars per share)	$ 17.97	$ 17.98	$ 17.98	$ 13.58	$ 11.03
Exercisable Options, Options (in shares)	139,491	145,804	145,804
Exercisable, weighted average exercise price per share (in dollars per share)	$ 17.79	$ 17.67	$ 17.67
Exercisable, weighted average contractual life (Year)	4 years 73 days		4 years 146 days