Intangible Assets - Reconciliation of Goodwill by Business Segment (Detail) $ in Millions	6 Months Ended
Mar. 31, 2019 USD ($)
Goodwill [Roll Forward]
Goodwill as of September 30, 2018	$ 23,600
Divestiture-related adjustments	3
Purchase accounting adjustments	(84)
Currency translation	(5)
Goodwill as of March 31, 2019	23,513
Medical
Goodwill [Roll Forward]
Goodwill as of September 30, 2018	10,054
Divestiture-related adjustments	0
Purchase accounting adjustments	(15)
Currency translation	(3)
Goodwill as of March 31, 2019	10,036
Life Sciences
Goodwill [Roll Forward]
Goodwill as of September 30, 2018	775
Divestiture-related adjustments	3
Purchase accounting adjustments	0
Currency translation	(2)
Goodwill as of March 31, 2019	776
Interventional
Goodwill [Roll Forward]
Goodwill as of September 30, 2018	12,771
Divestiture-related adjustments	0
Purchase accounting adjustments	(70)
Currency translation	0
Goodwill as of March 31, 2019	$ 12,701

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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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 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.

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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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