Intangible Assets - Reconciliation of Goodwill by Business Segment (Detail) $ in Millions	9 Months Ended
Jun. 30, 2018 USD ($)
Goodwill [Roll Forward]
Goodwill as of September 30, 2017	$ 7,563
Acquisitions	15,139
Divestitures	(55)
Reallocation of goodwill for change in segment and reporting unit composition	0
Purchase accounting adjustments	878
Currency translation	(20)
Goodwill as of June 30, 2018	23,505
Medical
Goodwill [Roll Forward]
Goodwill as of September 30, 2017	6,802
Acquisitions	4,389
Divestitures	0
Reallocation of goodwill for change in segment and reporting unit composition	(877)
Purchase accounting adjustments	216
Currency translation	(19)
Goodwill as of June 30, 2018	10,511
Life Sciences
Goodwill [Roll Forward]
Goodwill as of September 30, 2017	761
Acquisitions	76
Divestitures	0
Reallocation of goodwill for change in segment and reporting unit composition	0
Purchase accounting adjustments	0
Currency translation	(1)
Goodwill as of June 30, 2018	836
Interventional
Goodwill [Roll Forward]
Goodwill as of September 30, 2017	0
Acquisitions	10,674
Divestitures	(55)
Reallocation of goodwill for change in segment and reporting unit composition	877
Purchase accounting adjustments	661
Currency translation	0
Goodwill as of June 30, 2018	$ 12,157

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 transfers into (out 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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