Intangible Assets - Reconciliation of Goodwill by Business Segment (Detail) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 7,419	$ 7,537
Divestiture (A)	(25)	(32)
Goodwill, Purchase Accounting Adjustments	4	(78)
Goodwill, Foreign Currency Translation Gain (Loss)	22	(8)
Acquisitions (C)	143
Goodwill, ending balance	7,563	7,419
Medical
Goodwill [Roll Forward]
Goodwill, beginning balance	6,688	6,807
Divestiture (A)	(25)	(32)
Goodwill, Purchase Accounting Adjustments	4	(79)
Goodwill, Foreign Currency Translation Gain (Loss)	16	(8)
Acquisitions (C)	119
Goodwill, ending balance	6,802	6,688
Life Sciences
Goodwill [Roll Forward]
Goodwill, beginning balance	731	730
Divestiture (A)	0	0
Goodwill, Purchase Accounting Adjustments	0	1
Goodwill, Foreign Currency Translation Gain (Loss)	6	0
Acquisitions (C)	24
Goodwill, ending balance	$ 761	$ 731

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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- 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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- Definition

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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- Definition

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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e961-128460

Reference 2: 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

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- Definition

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

+ References

No definition available.

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- Definition

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.

+ References

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