Goodwill and Intangibles (Details) (USD $) In Thousands	9 Months Ended
Jul. 03, 2011	Jul. 03, 2011 Engineering and consulting services (ECS)	Jul. 03, 2011 Technical support services (TSS)	Jul. 03, 2011 Engineering and architecture services (EAS)	Jul. 03, 2011 Remediation and construction management (RCM)	Oct. 03, 2010 Remediation and construction management (RCM)
Goodwill
Balance at beginning of the period	$ 394,422	$ 244,616	$ 68,661	$ 17,210	$ 63,935	$ 63,935
Goodwill Additions	137,091	137,091
Currency Translation Adjustments	16,446	16,446
Goodwill Adjustments	16,167	14,474	1,193	500
Balance at end of the period	$ 564,126	$ 412,627	$ 69,854	$ 17,710	$ 63,935	$ 63,935

The increase (decrease) to the recorded value of goodwill for foreign currency translation adjustments.

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- Definition

Carrying amount as of the balance sheet date, which is the cumulative amount paid, adjusted for any amortization recognized prior to adoption of FAS 142 and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 43

+ Details

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- Definition

The aggregate amount of goodwill acquired in the period and allocated to the reportable segment. The value is stated at fair value based on the purchase price allocation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 45
-Subparagraph e(1)

+ Details

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- Definition

Purchase price allocation adjustment for allocation not yet complete at the prior year end.

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ Details

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