Note 11 - Employee Equity Incentive Plans - Option Activity (Details) - USD ($) $ in Thousands		3 Months Ended
		Jun. 30, 2015
Options outstanding (in shares)		4,588,347
Options outstanding (in dollars per share)		$ 10.20
Options granted (in shares)		293,000
Options granted (in dollars per share)		$ 13.37
Options exercised (in shares)		(211,876)
Options exercised (in dollars per share)		$ 9.30
Options exercised	[1]	$ 1,040
Options cancelled (in shares)		(2,500)
Options cancelled (in dollars per share)		$ 12.13
Options expired (in shares)		(432,788)
Options expired (in dollars per share)		$ 14.70
Options exercisable (in shares)		3,387,597
Options exercisable (in dollars per share)		$ 9.73

[1] Represents the difference between the exercise price and the value of our common stock at the time of exercise.