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=77989000&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.

+ References

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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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Amount of loss from the write-down 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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

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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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Summary of Significant Accounting Policies - Rollforward of Goodwill Activity by Reportable Segments (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Sep. 29, 2018	Sep. 30, 2017	Sep. 24, 2016
Goodwill [Roll Forward]
Balance at September 30, 2017		$ 3,171,200,000
Goodwill, Impairment Loss	$ (685,700,000)	(685,700,000)	$ 0	$ 0
Foreign currency and other adjustments		400,000
Balance at September 29, 2018		2,533,200,000	3,171,200,000
Diagnostics
Goodwill [Roll Forward]
Balance at September 30, 2017		823,000,000
Goodwill, Impairment Loss		0
Foreign currency and other adjustments		(1,800,000)
Balance at September 29, 2018		821,200,000	823,000,000
Breast Health
Goodwill [Roll Forward]
Balance at September 30, 2017		641,500,000
Goodwill, Impairment Loss		0
Foreign currency and other adjustments		700,000
Balance at September 29, 2018		689,500,000	641,500,000
Medical Aesthetics
Goodwill [Roll Forward]
Balance at September 30, 2017		683,500,000
Goodwill, Impairment Loss		(685,700,000)
Foreign currency and other adjustments		2,200,000
Balance at September 29, 2018		0	683,500,000
GYN Surgical
Goodwill [Roll Forward]
Balance at September 30, 2017		1,015,100,000
Goodwill, Impairment Loss		0
Foreign currency and other adjustments		(700,000)
Balance at September 29, 2018		1,014,400,000	1,015,100,000
Skeletal Health
Goodwill [Roll Forward]
Balance at September 30, 2017		8,100,000
Goodwill, Impairment Loss		0
Foreign currency and other adjustments		0
Balance at September 29, 2018		8,100,000	$ 8,100,000
Faxitron
Goodwill [Roll Forward]
Faxitron acquisition		41,600,000
Faxitron \| Diagnostics
Goodwill [Roll Forward]
Faxitron acquisition		0
Faxitron \| Breast Health
Goodwill [Roll Forward]
Faxitron acquisition		41,600,000
Faxitron \| Medical Aesthetics
Goodwill [Roll Forward]
Faxitron acquisition		0
Faxitron \| GYN Surgical
Goodwill [Roll Forward]
Faxitron acquisition		0
Faxitron \| Skeletal Health
Goodwill [Roll Forward]
Faxitron acquisition		0
Emsor
Goodwill [Roll Forward]
Faxitron acquisition		5,700,000
Emsor \| Diagnostics
Goodwill [Roll Forward]
Faxitron acquisition		0
Emsor \| Breast Health
Goodwill [Roll Forward]
Faxitron acquisition		5,700,000
Emsor \| Medical Aesthetics
Goodwill [Roll Forward]
Faxitron acquisition		0
Emsor \| GYN Surgical
Goodwill [Roll Forward]
Faxitron acquisition		0
Emsor \| Skeletal Health
Goodwill [Roll Forward]
Faxitron acquisition		$ 0