Note 2 - Summary of Significant Accounting Policies (Detail) - Stock Option Activity (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013
Outstanding at December 31, 2012	9,463,657
Outstanding at December 31, 2012 (in Dollars per share)	$ 11.76
Outstanding at March 31, 2013	9,356,934
Outstanding at March 31, 2013 (in Dollars per share)	$ 11.93
Outstanding at March 31, 2013	7 years 328 days
Outstanding at March 31, 2013 (in Dollars)	$ 61,857
Exercisable at March 31, 2013	5,158,810
Exercisable at March 31, 2013 (in Dollars per share)	$ 10.63
Exercisable at March 31, 2013	7 years 146 days
Exercisable at March 31, 2013 (in Dollars)	$ 40,459
Options granted	365,000
Options granted (in Dollars per share)	$ 14.24
Options forfeited	(137,202)
Options forfeited (in Dollars per share)	$ 15.34
Options exercised	(334,121)
Options exercised (in Dollars per share)	$ 8.58