Warranty - Schedule of Product Warranty Liability (Details)
$ in Thousands
9 Months Ended
Jan. 31, 2016
USD ($)
Product Warranties Disclosures [Abstract]  
Warranty period 1 year
Movement in Standard Product Warranty Accrual  
Beginning balance at May 3, 2015 $ 6,451
Additions during the period based on product sold 7,431
Decrease in estimates (752)
Settlements and expirations (2,528)
Ending balance at January 31, 2016 $ 10,602