Summary of Significant Accounting Policies - Additional Information (Details) $ in Thousands	12 Months Ended
	Apr. 30, 2016 USD ($) Customer	Apr. 30, 2015 USD ($) Customer	Apr. 30, 2014 USD ($) Customer
Accounting Policies [Abstract]
Foreign Currency Transaction Gain (Loss), before Tax	$ (400)	$ (1,000)	$ 400
Other than Temporary Impairment Losses, Investments	0	0	$ 0
Allowance for doubtful accounts	$ 2,362	$ 3,992
Number of clients that accounted for more than 10% of account receivables | Customer	0	0
Number of clients that accounted for more than 10% of revenue | Customer	0	0	0
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Stock-based expense	$ 14,761	$ 12,201	$ 13,827
Software as a Service (“SaaS”)
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Service agreement period	1 year