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Debt - Interest Expense (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	May 03, 2015	Apr. 27, 2014	Apr. 28, 2013
Debt Instrument [Line Items]
Amortization of the debt discount	$ 9,153	$ 3,151	$ 0
0.5% Convertible Senior Notes Due 2033 \| Convertible Debt
Debt Instrument [Line Items]
Contractual interest expense	1,294
Amortization of the debt discount	9,153
Amortization of issuance costs	616
Total interest cost	$ 11,063
Liability [Member] \| 0.5% Convertible Senior Notes Due 2033 \| Convertible Debt
Debt Instrument [Line Items]
Effective interest rate on the liability component	4.87%