Acquisitions - Pro Forma Results (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended	12 Months Ended
Apr. 27, 2013	Apr. 28, 2012	Apr. 27, 2013	Jul. 28, 2012
Business Acquisition, Pro Forma Information [Abstract]
Revenue	$ 437,367	$ 407,607	$ 1,358,621	$ 1,264,751
Income (loss) before income taxes	16,762	5,872	62,988	19,974
Net income (loss)	$ 10,220	$ 3,619	$ 37,856	$ 12,104
Business Acquisition, Pro Forma Information, Earnings (Loss) Per Share [Abstract]
Basic	$ 0.31	$ 0.11	$ 1.15	$ 0.36
Diluted	$ 0.30	$ 0.10	$ 1.12	$ 0.35

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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