Note 8 - Share-based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Outstanding (in shares)	5,119	5,067	5,283
Outstanding (in dollars per share)	$ 11.82	$ 11.70	$ 11.69
Outstanding (Year)	3 years 313 days	4 years 149 days	5 years 146 days	6 years 131 days
Outstanding		$ 2,874	$ 21,395	$ 65,351
Granted (in shares)	0	267
Granted (in dollars per share)		$ 10.49
Exercised (in shares)		(154)	(159)
Exercised (in dollars per share)		$ 2.94	$ 5.23
Forfeited (in shares)	(703)	(61)	(57)
Forfeited (in dollars per share)	$ 3.19	$ 19.03	$ 29
Outstanding (in shares)	4,416	5,119	5,067	5,283
Outstanding (in dollars per share)	$ 13.18	$ 11.82	$ 11.70	$ 11.69
Exercisable at December 31, 2016 (in shares)	4,416
Exercisable at December 31, 2016 (in dollars per share)	$ 13.18
Exercisable at December 31, 2016 (Year)	3 years 313 days
Exercisable at December 31, 2016