Acquisitions - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Business Acquisition [Line Items]
Net increase in goodwill	$ 22
Goodwill	14,897	$ 14,890
Teneobio
Business Acquisition [Line Items]
Net increase in goodwill	22
Cash paid	993
Maximum additional consideration due contingent on certain milestones	1,600
Contingent consideration obligation for acquisition	299
Deferred tax liability	244
Goodwill	273
Teneobio \| R & D Technology rights
Business Acquisition [Line Items]
Value of intangible assets acquired	$ 115
Weighted average period of amortization	10 years
Teneobio \| Licensing rights
Business Acquisition [Line Items]
Value of intangible assets acquired	$ 41
Teneobio \| In-process Research and Development
Business Acquisition [Line Items]
Acquired in-process research and development	991
Teneobio \| In-process Research and Development \| AMG 340
Business Acquisition [Line Items]
Acquired in-process research and development	$ 784

Business Combination, Fair Value of Contingent Consideration Arrangements, Addition from Acquisitions

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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Amount of deferred tax liability attributable to taxable temporary differences assumed at the acquisition date.

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Amount of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit, acquired at the acquisition date.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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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 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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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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