Note 2 - Stock-Based Compensation (Details) - Stock Options - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Stock Options [Abstract]
Outstanding at January 1, 2015		590
Outstanding at January 1, 2015		$ 15.80
Outstanding at January 1, 2015	1 year 109 days	1 year 73 days
Outstanding at January 1, 2015		$ 20,039
Outstanding at September 30, 2015	151
Outstanding at September 30, 2015	$ 16.13
Outstanding at September 30, 2015	1 year 109 days	1 year 73 days
Outstanding at September 30, 2015	$ 5,294
Options exercisable at September 30, 2015 and expected to vest	151
Options exercisable at September 30, 2015 and expected to vest	$ 16.13
Options exercisable at September 30, 2015 and expected to vest	1 year 109 days
Options exercisable at September 30, 2015 and expected to vest	$ 5,294
Options exercisable at September 30, 2015	149
Options exercisable at September 30, 2015	$ 16.19
Options exercisable at September 30, 2015	1 year 73 days
Options exercisable at September 30, 2015	$ 5,213
Exercised	(438)
Exercised	$ 15.69
Forfeited and expired	(1)
Forfeited and expired	$ 15.95