Note 2 - Stock-Based Compensation (Details) - Stock Options (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Stock Options [Abstract]
Outstanding	516	590
Outstanding	$ 15.56	$ 15.80
Outstanding	1 year	1 year 73 days
Outstanding	$ 19,132	$ 20,039
Options exercised	(74)
Options exercised	$ 17.49
Options exercisable at March 31, 2015 and expected to vest	516
Options exercisable at March 31, 2015 and expected to vest	$ 15.56
Options exercisable at March 31, 2015 and expected to vest	1 year
Options exercisable at March 31, 2015 and expected to vest	19,126
Options exercisable at March 31, 2015	503
Options exercisable at March 31, 2015	$ 15.64
Options exercisable at March 31, 2015	328 days
Options exercisable at March 31, 2015	$ 18,617