Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Apr. 28, 2018	Apr. 29, 2017
Assets:
Cash equivalents	$ 6,650	$ 6,798
Deferred purchase price receivable	150,404	119,798
Derivative instruments	1,613	1,188
Total assets	158,667	127,784
Liabilities:
Derivative instruments	1,613	1,188
Level 1
Assets:
Cash equivalents	6,650	6,798
Deferred purchase price receivable	0	0
Derivative instruments	0	0
Total assets	6,650	6,798
Liabilities:
Derivative instruments	0	0
Level 2
Assets:
Cash equivalents	0	0
Deferred purchase price receivable	0	0
Derivative instruments	1,613	1,188
Total assets	1,613	1,188
Liabilities:
Derivative instruments	1,613	1,188
Level 3
Assets:
Cash equivalents	0	0
Deferred purchase price receivable	150,404	119,798
Derivative instruments	0	0
Total assets	150,404	119,798
Liabilities:
Derivative instruments	$ 0	$ 0