Note 9 - Income Taxes - Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Federal, current	$ 11,951	$ 124	$ (94)
Federal, deferred	(2,925)	18,185	12,830
State, current	1,811	426	187
State, deferred	(451)	3,087	1,851
	$ 10,386	$ 21,822	$ 14,774