Note 16 - Stockholders' Equity (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Stockholders' Equity Attributable to Parent	$ 1,857,902		$ 1,828,539
Stockholders' Equity, Period Increase (Decrease)	29,400
Net Income (Loss) Attributable to Parent	48,941	$ 46,163
Dividends, Common Stock, Cash	16,800
Adjustments Related to Tax Withholding for Share-based Compensation	$ 5,100
U.S. Treasury [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	943,345		943,345	1,846,374
Class of Warrant or Right, Exercise Price of Warrants or Rights			$ 20.65	$ 20.96
Class of Warrant or Right, Increase in Warrants Exercisable, Percentage			1.50%