Intangible Assets - Reconciliation of Goodwill by Business Segment (Detail) $ in Millions	9 Months Ended
Jun. 30, 2019 USD ($)
Goodwill [Roll Forward]
Goodwill as of September 30, 2018	$ 23,600
Divestiture-related adjustments	3
Purchase accounting adjustments	(90)
Currency translation	(14)
Goodwill as of June 30, 2019	23,498
Medical
Goodwill [Roll Forward]
Goodwill as of September 30, 2018	10,054
Divestiture-related adjustments	0
Purchase accounting adjustments	(15)
Currency translation	(12)
Goodwill as of June 30, 2019	10,027
Life Sciences
Goodwill [Roll Forward]
Goodwill as of September 30, 2018	775
Divestiture-related adjustments	3
Purchase accounting adjustments	0
Currency translation	(3)
Goodwill as of June 30, 2019	775
Interventional
Goodwill [Roll Forward]
Goodwill as of September 30, 2018	12,771
Divestiture-related adjustments	0
Purchase accounting adjustments	(75)
Currency translation	0
Goodwill as of June 30, 2019	$ 12,696

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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