Intangible Assets - Reconciliation of Goodwill by Business Segment (Detail) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2016	Sep. 30, 2015
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 7,537	$ 1,090
Acquisitions		6,716
Divestiture	(32)
Purchase accounting adjustments/currency translation	(86)	(269)
Goodwill, ending balance	7,419	7,537
Medical
Goodwill [Roll Forward]
Goodwill, beginning balance	6,807	482
Acquisitions		6,585
Divestiture	(32)
Purchase accounting adjustments/currency translation	(87)	(261)
Goodwill, ending balance	6,688	6,807
Medical \| Series of Individually Immaterial Business Acquisitions
Goodwill [Roll Forward]
Acquisitions		22
Life Sciences
Goodwill [Roll Forward]
Goodwill, beginning balance	730	608
Acquisitions		130
Divestiture	0
Purchase accounting adjustments/currency translation	1	(8)
Goodwill, ending balance	$ 731	$ 730

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 increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing 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 1
-Subparagraph (g)
-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
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-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e961-128460

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Amount of divestiture 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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