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Goodwill and Intangible Assets - Annual Impairment Analyses (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jul. 26, 2014	Jul. 27, 2013	Jul. 28, 2012
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 269,088	$ 267,810	$ 174,849
Goodwill
Finite-Lived Intangible Assets [Line Items]
Discount rate	11.50%	11.50%	13.00%
Goodwill | Maximum
Finite-Lived Intangible Assets [Line Items]
Terminal growth rate range	1.50%	1.50%	1.50%
Goodwill | Minimum
Finite-Lived Intangible Assets [Line Items]
Terminal growth rate range	3.00%	2.50%	3.00%
Businesses Acquired in Fiscal 2013
Finite-Lived Intangible Assets [Line Items]
Number of Reporting Units that Exceeded Carrying Value	3
Excess carrying value, percent	25.00%
First Reporting Unit Acquired in Fiscal 2013
Finite-Lived Intangible Assets [Line Items]
Goodwill	10,600
Second Reporting Unit Acquired in Fiscal 2013
Finite-Lived Intangible Assets [Line Items]
Goodwill	4,800
Third Reporting Unit Acquired in Fiscal 2013
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 3,600

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- Definition

Fair Value Assumptions, Terminal Growth Rate

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Number of Reporting Units that Exceeded Carrying Value

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267



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-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

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-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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Percentage of fair value of reporting unit in excess of carrying amount.

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