Reportable Segments - Financial Information (Details) $ in Thousands	3 Months Ended
Dec. 29, 2019 USD ($) segment	Dec. 30, 2018 USD ($)	Sep. 29, 2019 USD ($)
Financial information regarding reportable segments
Number of reportable segments \| segment	2
Revenue	$ 797,623	$ 717,431
Income from operations	63,302	55,711
Total Assets	2,352,553		$ 2,147,408
Operating segment \| GSG
Financial information regarding reportable segments
Revenue	457,404	411,971
Income from operations	42,048	37,413
Total Assets	588,062		587,040
Operating segment \| CIG
Financial information regarding reportable segments
Revenue	351,164	317,793
Income from operations	31,632	27,099
Total Assets	414,926		450,276
Operating segment \| RCM
Financial information regarding reportable segments
Revenue	145	1,453
Income from operations	1	4
Total Assets	14,358		15,608
Elimination of inter-segment revenue
Financial information regarding reportable segments
Revenue	(11,090)	(13,786)
Corporate
Financial information regarding reportable segments
Income from operations	(10,379)	$ (8,805)
Total Assets	$ 1,335,207		$ 1,094,484

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.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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