Condensed Consolidated Statements of Changes in Stockholders' Equity (USD $) In Thousands	Total USD ($)	Common Stock USD ($)	Treasury Stock	Additional Paid-in Capital USD ($)	Accumulated Other Comprehensive Income (Loss) USD ($)	Accumulated Deficit USD ($)
Beginning balance at Apr. 30, 2014	$ 206,462	$ 8		$ 398,201	$ 328	$ (192,075)
Beginning balance, Shares at Apr. 30, 2014		77,888	(250)
Excess tax benefit related to stock-based expense	2			2
Stock-based expense	9,689			9,689
Issuance of restricted stock awards		115
Exercise of stock options and vested restricted stock units, Shares		1,445
Exercise of stock options and vested restricted stock units	4,356			4,356
Shares issued under employee stock plans , Shares		182
Shares issued under employee stock plans	1,195			1,195
Change in foreign currency translation adjustment	(968)				(968)
Change in unrealized gain (loss) on investments	(39)				(39)
Net loss applicable to common stockholders	(25,596)					(25,596)
Ending balance at Jan. 31, 2015	$ 195,101	$ 8		$ 413,443	$ (679)	$ (217,671)
Ending balance, Shares at Jan. 31, 2015		79,630	(250)