Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended		9 Months Ended
	Jan. 31, 2016 Customer revenue_source	Jan. 31, 2015 Customer	Jan. 31, 2016 Customer revenue_source	Apr. 30, 2015 Customer
Accounting Policies [Abstract]
Number of clients that accounted for more than 10% of account receivables	0		0	0
Number of clients that accounted for more than 10% of revenue	0	0
Software as a Service (“SaaS”)
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Revenue sources | revenue_source	2		2
Service agreement period			1 year