Acquisitions - Pro Forma Results (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Oct. 27, 2012
Business Acquisition, Pro Forma Information [Abstract]
Pro forma contract revenues	$ 499,666
Pro forma income before income taxes	36,205
Pro forma net income	$ 22,019
Business Acquisition, Pro Forma Information, Earnings (Loss) Per Share [Abstract]
Basic	$ 0.67
Diluted	$ 0.65

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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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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- Definition

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

+ Details

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- Definition

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.

+ References

+ Details

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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.

+ References

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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.

+ References

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