Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Jan. 26, 2019	Apr. 28, 2018
Assets:
Cash equivalents	$ 1,895	$ 6,650
DPP receivable - receivables securitization program	58,322	0
DPP receivable - customer financing	111,461	150,404
Derivative instruments	1,169	1,613
Total assets	172,847	158,667
Liabilities:
Derivative instruments	1,453	1,613
Fair Value, Inputs, Level 1
Assets:
Cash equivalents	1,895	6,650
DPP receivable - receivables securitization program	0	0
DPP receivable - customer financing	0	0
Derivative instruments	0	0
Total assets	1,895	6,650
Liabilities:
Derivative instruments	0	0
Fair Value, Inputs, Level 2
Assets:
Cash equivalents	0	0
DPP receivable - receivables securitization program	0	0
DPP receivable - customer financing	0	0
Derivative instruments	1,169	1,613
Total assets	1,169	1,613
Liabilities:
Derivative instruments	1,453	1,613
Fair Value, Inputs, Level 3
Assets:
Cash equivalents	0	0
DPP receivable - receivables securitization program	58,322	0
DPP receivable - customer financing	111,461	150,404
Derivative instruments	0	0
Total assets	169,783	150,404
Liabilities:
Derivative instruments	$ 0	$ 0