Stockholders' Equity (Details)	1 Months Ended
	Aug. 31, 2009 item shares	Mar. 31, 2017 shares	Mar. 31, 2016 shares
Common Stock Reserved for Future Issuance
Stock options outstanding (in shares)		3,776,000
Restricted stock units outstanding (in shares)		232,000
Authorized for future issuance under stock incentive plans (in shares)		2,443,000
Common stock reserved for future issuance (in shares)		6,451,000
Preferred Stock
Authorized shares of preferred stock		2,000,000	2,000,000
Outstanding shares of preferred stock		0	0
Stockholder Rights Plan
Common Stock Warrants
Number of preferred stock purchase rights distributed as dividend for each shares of common stock held (in shares)	1
Number of shares of Series A Junior Participating Preferred Stock that each right will enable the holder to buy	0.001
Number of series of junior participating preferred stock eliminated | item	2