Note 2 - Summary of Significant Accounting Policies (Details) - Stock Option Activity (USD $) In Thousands, except Share data, unless otherwise specified	6 Months Ended
	Jun. 30, 2013
Stock Option Activity [Abstract]
Outstanding at December 31, 2012	9,463,657
Outstanding at December 31, 2012 (in Dollars per share)	$ 11.76
Outstanding at June 30, 2013	8,893,393
Outstanding at June 30, 2013 (in Dollars per share)	$ 12.09
Outstanding at June 30, 2013	7 years 255 days
Outstanding at June 30, 2013 (in Dollars)	$ 84,991
Exercisable at June 30, 2013	5,246,938
Exercisable at June 30, 2013 (in Dollars per share)	$ 11.30
Exercisable at June 30, 2013	7 years 73 days
Exercisable at June 30, 2013 (in Dollars)	$ 54,529
Options granted	426,000
Options granted (in Dollars per share)	$ 14.91
Options forfeited	(268,883)
Options forfeited (in Dollars per share)	$ 15.61
Options exercised	(727,181)
Options exercised (in Dollars per share)	$ 8.32