Condensed Consolidated Statements of Comprehensive Loss (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2015	Jan. 31, 2014
Net loss	$ (4,123)us-gaap_NetIncomeLoss	$ (7,963)us-gaap_NetIncomeLoss	$ (25,596)us-gaap_NetIncomeLoss	$ (39,485)us-gaap_NetIncomeLoss
Other comprehensive gain (loss), net of tax:
Foreign currency translation adjustment	(510)	136	(968)	269
Unrealized gain (loss) on investments	(57)	44	(39)	90
Total other comprehensive gain (loss), net of tax	(567)	180	(1,007)	359
Comprehensive loss	$ (4,690)us-gaap_ComprehensiveIncomeNetOfTax	$ (7,783)us-gaap_ComprehensiveIncomeNetOfTax	$ (26,603)us-gaap_ComprehensiveIncomeNetOfTax	$ (39,126)us-gaap_ComprehensiveIncomeNetOfTax

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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