Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Reportable Segments (Details) (USD $) In Thousands	3 Months Ended								12 Months Ended
Reportable Segments (Details) (USD $) In Thousands	Oct. 02, 2011	Jul. 03, 2011	Apr. 03, 2011	Jan. 02, 2011	Oct. 03, 2010	Jun. 27, 2010	Mar. 28, 2010	Dec. 27, 2009	Oct. 02, 2011	Oct. 03, 2010	Sep. 27, 2009
Financial information concerning reportable segments
Revenue	$ 675,662	$ 673,792	$ 612,566	$ 611,124	$ 627,382	$ 562,365	$ 469,528	$ 541,957	$ 2,573,144	$ 2,201,232	$ 2,287,484
Segment operating income	43,433	39,408	29,256	34,325	37,124	32,706	23,527	31,117	146,422	124,474	121,889
Total assets	1,593,988				1,381,689				1,593,988	1,381,689	1,097,905
Engineering and consulting services (ECS)
Financial information concerning reportable segments
Revenue									1,107,944	730,425	601,317
Segment operating income									100,790	60,810	47,095
Total assets	913,167				618,025				913,167	618,025	486,002
Technical support services (TSS)
Financial information concerning reportable segments
Revenue									568,335	527,697	522,748
Segment operating income									40,895	39,186	37,584
Total assets	338,379				281,376				338,379	281,376	223,177
Engineering and architecture services (EAS)
Financial information concerning reportable segments
Revenue									308,112	294,112	299,691
Segment operating income									22,597	12,194	13,599
Total assets	111,555				93,696				111,555	93,696	91,646
Remediation and construction management (RCM)
Financial information concerning reportable segments
Revenue									725,569	759,088	951,604
Segment operating income									18,746	33,651	38,156
Total assets	317,514				327,393				317,514	327,393	351,247
Reportable Segments
Financial information concerning reportable segments
Revenue									2,709,960	2,311,322	2,375,360
Segment operating income									183,028	145,841	136,434
Total assets	$ 1,680,615				$ 1,320,490				$ 1,680,615	$ 1,320,490	$ 1,152,072