Note 10 - Stock Based Compensation (Detail) - Summary of Stock Option Activity (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Outstanding at January 1, 2010	3,113,144	2,167,646	1,641,979
Outstanding at January 1, 2010 (in Dollars per share)	$ 3.75	$ 3.96	$ 3.96
Granted	655,251	1,195,667	656,500
Granted (in Dollars per share)	$ 2.24	$ 3.67	$ 3.04
Exercised	(214,091)
Exercised (in Dollars per share)	$ 3.26
Canceled or expired	(289,424)	(250,169)	(130,833)
Canceled or expired (in Dollars per share)	$ 6.54	$ 3.23	$ 3.03
Outstanding	3,264,880	3,113,144	2,167,646
Outstanding (in Dollars per share)	$ 3.25	$ 3.75	$ 3.96
Outstanding	6 years 255 days
Outstanding (in Dollars)	$ 16,168,796
Exercisable at December 31, 2012	1,910,025
Exercisable at December 31, 2012 (in Dollars per share)	$ 3.76
Exercisable at December 31, 2012	5 years 146 days
Exercisable at December 31, 2012 (in Dollars)	$ 8,487,064