Goodwill and Intangible Assets - Activity of Goodwill by Reportable Operating Segment (Detail) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2016	Oct. 02, 2015
Goodwill [Roll Forward]
Balance, beginning	$ 283.5	$ 240.6
Business combinations	11.4	49.2
Foreign currency translation adjustments	(0.2)	(6.3)
Balance, ending	294.7	283.5
Oncology Systems
Goodwill [Roll Forward]
Balance, beginning	158.8	148.3
Business combinations	11.4	10.5
Foreign currency translation adjustments	0.0	0.0
Balance, ending	170.2	158.8
Imaging Components
Goodwill [Roll Forward]
Balance, beginning	74.7	36.0
Business combinations	0.0	38.7
Foreign currency translation adjustments	0.0	0.0
Balance, ending	74.7	74.7
Other
Goodwill [Roll Forward]
Balance, beginning	50.0	56.3
Business combinations	0.0	0.0
Foreign currency translation adjustments	(0.2)	(6.3)
Balance, ending	$ 49.8	$ 50.0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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