Reportable Segments - Financial Information (Details) $ in Thousands	3 Months Ended
Dec. 31, 2017 USD ($) segment	Jan. 01, 2017 USD ($)	Oct. 01, 2017 USD ($)
Financial information regarding reportable segments
Number of renamed reportable segments \| segment	2
Revenue	$ 759,749	$ 668,851
Income (loss) from operations	48,589	39,855
Total Assets	1,970,987		$ 1,902,745
Operating segment \| GSG
Financial information regarding reportable segments
Revenue	442,772	362,859
Income (loss) from operations	39,125	30,168
Total Assets	489,893		378,839
Operating segment \| CIG
Financial information regarding reportable segments
Revenue	331,513	318,071
Income (loss) from operations	21,294	21,544
Total Assets	481,924		518,697
Operating segment \| RCM
Financial information regarding reportable segments
Revenue	6,807	8,231
Income (loss) from operations	(1,158)	(3,042)
Total Assets	33,030		33,620
Elimination of inter-segment revenue
Financial information regarding reportable segments
Revenue	(21,343)	(20,310)
Corporate
Financial information regarding reportable segments
Income (loss) from operations	(10,672)	$ (8,815)
Total Assets	$ 966,140		$ 971,589

Number Of Renamed Reportable Segments

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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+ References

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Aggregate revenue during the period from services rendered in the normal course of business, after deducting allowances and discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(d))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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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.

+ References

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