Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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Face (par) amount of debt instrument at time of issuance.

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Debt Components of the Convertible Notes (Details) - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
	Sep. 15, 2015	Jul. 30, 2016	Jul. 30, 2016	Jul. 25, 2015	Jul. 26, 2014
Debt Instrument [Line Items]
Payments of Debt Issuance Costs			$ 16,376	$ 3,854	$ 0
Amortization of debt discount			14,709	$ 0	$ 0
0.75% Convertible Notes Liability Component [Member]
Debt Instrument [Line Items]
Debt Issuance Cost	$ (11,500)
Amortization of debt discount			1,200
0.75% Convertible Notes Equity Component [Member]
Debt Instrument [Line Items]
Debt Issuance Cost	(3,600)
0.75% Convertible Senior Notes Due 2021
Debt Instrument [Line Items]
Debt Instrument, Face Amount	485,000	$ 485,000	485,000
Debt Instrument, Unamortized Discount		(101,679)	(101,679)
Debt Issuance Cost	(15,100)	(10,244)	(10,244)
Net carrying amount of Notes		373,077	373,077
Equity component of 0.75% senior convertible notes due 2021, net		112,554	$ 112,554
Debt Instrument, Unamortized Discount (Premium), Net	13,300
Payments of Debt Issuance Costs	$ 1,800
Amortization of debt discount		$ 14,700