Note 7 - Stock-based Compensation Expense and Related Income Tax Benefit (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Stock-based compensation expense, gross	$ 1,009	$ 981	$ 3,011	$ 4,032
Income tax benefit at our statutory rate associated with stock-based compensation	(394)	(383)	(1,174)	(1,572)
Stock-based compensation expense, net	$ 615	$ 598	$ 1,837	$ 2,460