Exercise price per share or per unit of warrants or rights outstanding.

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The price per share of the conversion feature embedded in the debt instrument.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from derivative instruments.

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The number of derivative instruments of a particular group held by the entity.

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The cash outflow for a financial contract that meets the hedge criteria as either cash flow hedge, fair value hedge or hedge of net investment in foreign operations.

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The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

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Debt - Convertible Note Hedge and Warrant Transactions (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		12 Months Ended
	Sep. 15, 2015	Jul. 29, 2017	Jul. 30, 2016	Jul. 25, 2015
Debt Instrument [Line Items]
Purchase of convertible note hedges		$ 0	$ 115,818	$ 0
Proceeds from sale of warrants		$ 0	$ 74,690	$ 0
Convertible Note Hedge
Debt Instrument [Line Items]
Derivative, Number of Instruments Held	5,006
Debt instrument, convertible, conversion price (per share)	$ 96.89	$ 96.89
Purchase of convertible note hedges	$ 115,800
Deferred Tax Liabilities, Derivatives	43,400
Deferred Tax Assets, Derivative Instruments	$ 43,200
0.75% Convertible Senior Notes Due 2021
Debt Instrument [Line Items]
Debt instrument, convertible, conversion price (per share)	$ 96.89
Purchase of convertible note hedges	$ 41,100
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (shares)	5,006
Class of earrant or right, exercise price of warrants or rights (per warrant)	$ 130.43	$ 130.43
Proceeds from sale of warrants	$ 74,700