GOODWILL AND INTANGIBLE ASSETS - Activity of Goodwill by Reportable Operating Segment (Detail) $ in Millions	6 Months Ended
Mar. 29, 2019 USD ($)
Goodwill [Roll Forward]
Balance, beginning	$ 293.6
Business combination	22.0
Measurement period adjustment to a business combination in prior year	(4.7)
Foreign currency translation adjustments	(1.6)
Balance, ending	309.3
Oncology Systems
Goodwill [Roll Forward]
Balance, beginning	242.1
Business combination	22.0
Measurement period adjustment to a business combination in prior year	(4.7)
Foreign currency translation adjustments	0.0
Balance, ending	259.4
Proton Solutions
Goodwill [Roll Forward]
Balance, beginning	51.5
Business combination	0.0
Foreign currency translation adjustments	(1.6)
Balance, ending	$ 49.9

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.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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- Definition

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.

+ References

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-Publisher FASB
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-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
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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.

+ References

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-Section 50
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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 25
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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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