Stock Plans (Assumptions Used In Black-Scholes Model) (Details) (USD $)	3 Months Ended		6 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Option Grants and Stock Purchase Rights
Expected volatility	58.00%	64.00%	58.00%	64.00%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
Risk-free interest rate	1.74%	1.98%	1.72%	1.88%
Weighted average expected option term, in years	5 years 110 days	6 years 73 days	5 years 73 days	6 years 37 days
Weighted average fair value of options granted, per share	$ 3.90	$ 5.76	$ 3.91	$ 5.62
Employee Stock Purchase Plan Rights
Expected volatility	46.00%	38.00%	46.00%	38.00%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
Risk-free interest rate	0.09%	0.11%	0.09%	0.11%
Weighted average expected option term, in years	0 years 9 months 0 days	0 years 9 months 0 days	0 years 9 months 0 days	0 years 9 months 0 days
Weighted average fair value of options granted, per share	$ 2.46	$ 2.60	$ 2.46	$ 2.60