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Segment Information (Revenues Earned Directly Or Indirectly From The U.S. Federal Government And Its Agencies) (Details)	12 Months Ended
	Sep. 30, 2011	Oct. 01, 2010	Oct. 02, 2009	Sep. 26, 2008
Percentage of revenue earned from the U.S. federal government and its agencies	24.40%	25.40%	20.30%
Percentage of revenue earned				10.00%
Motiva Enterprises LLC [Member]
Percentage of revenue earned			12.20%

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Percentage of revenue earned from the U.S. federal government and their agencies

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