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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The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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

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Amount, after accumulated amortization, of debt discount (premium).

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Debt Components of the Convertible Notes (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Sep. 15, 2015	Apr. 29, 2017	Apr. 23, 2016	Apr. 29, 2017	Apr. 23, 2016	Jul. 30, 2016
Debt Instrument [Line Items]
Equity component of 0.75% senior convertible notes due 2021, net		$ 112,600		$ 112,600
Payments of Debt Issuance Costs				70	$ 15,542
Amortization of debt discount				13,111	10,119
0.75% Convertible Notes Liability Component [Member]
Debt Instrument [Line Items]
Debt Issuance Cost	$ (11,500)
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		$ 485,000
Debt Instrument, Unamortized Discount		(88,568)		(88,568)		(101,679)
Debt Issuance Cost	(15,100)	(9,103)		(9,103)		(10,244)
Net carrying amount of Notes		387,329		387,329		$ 373,077
Debt Instrument, Unamortized Discount (Premium), Net	13,300
Payments of Debt Issuance Costs	$ 1,800
Amortization of debt discount		$ 4,400	$ 4,200	$ 13,100	$ 10,100