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Description Of Business And Basis Of Presentation (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2011	Oct. 01, 2010	Oct. 02, 2009
Description Of Business And Basis Of Presentation
Cost-reimbursable	81.00%	86.00%	85.00%
Fixed-price	16.00%	13.00%	14.00%
Guaranteed maximum price	3.00%	1.00%	1.00%
Claim receivable write-off	$ 25.9

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Basis of Presentation

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Claim Receivable Write Off

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Revenue From Cost Reimbursable Contracts Percentage

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Revenue From Fixed Price Contracts Percentage

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Revenue From Guaranteed Maximum Price Contracts Percentage

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