Acquisitions - Pro Forma Results (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jan. 26, 2013	Jan. 26, 2013
Business Acquisition, Pro Forma Information [Abstract]
Pro forma contract revenues	$ 421,588	$ 921,254
Pro forma income before income taxes	7,546	44,049
Pro forma net income	$ 4,528	$ 26,430
Business Acquisition, Pro Forma Information, Earnings (Loss) Per Share [Abstract]
Basic	$ 0.14	$ 0.80
Diluted	$ 0.14	$ 0.79

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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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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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