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

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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Debt Components of the Convertible Notes (Details) - USD ($) $ in Thousands		3 Months Ended
	Sep. 15, 2015	Oct. 29, 2016	Oct. 24, 2015	Jul. 30, 2016
Debt Instrument [Line Items]
Payments of Debt Issuance Costs		$ 0	$ 14,494
Amortization of debt discount		4,307	1,780
0.75% Convertible Notes Liability Component [Member]
Debt Instrument [Line Items]
Debt Issuance Cost	$ (11,500)
Amortization of debt discount		400	100
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		(97,372)		(101,679)
Debt Issuance Cost	(15,100)	(9,877)		(10,244)
Net carrying amount of Notes		377,751		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		$ 4,300	$ 1,800