Debt Schedule of Debt (Details) - USD ($) $ in Thousands	Apr. 29, 2017	Jul. 30, 2016
Debt Instrument [Line Items]
Debt and capital lease obligations	$ 826,017	$ 719,327
Less: current portion	(14,438)	(13,125)
Long-term debt	811,579	706,202
0.75% Convertible Senior Notes Due 2021
Debt Instrument [Line Items]
Debt and capital lease obligations	387,329	373,077
Convertible Debt	$ 387,329	$ 373,077
Debt, interest rate (in percent)	0.75%	0.75%
7.125% Senior Subordinated Notes Due 2021
Debt Instrument [Line Items]
Debt, interest rate (in percent)		7.125%
Credit Agreement - Revolving facility (matures April 2020)
Debt Instrument [Line Items]
Debt and capital lease obligations	$ 71,000	$ 0
Credit Agreement - Term Loan (matures April 2020)
Debt Instrument [Line Items]
Debt and capital lease obligations	$ 367,688	$ 346,250

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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