Business Combinations - Summary of Amount Assigned to Identifiable Intangible Assets (Details) $ in Millions	Aug. 18, 2021 USD ($)
GRAIL Inc
Business Acquisition [Line Items]
Total intangible assets	$ 3,180
In-process research and development (IPR&D) \| GRAIL Inc
Business Acquisition [Line Items]
Indefinite lived intangible assets acquired	$ 670
Developed technology
Business Acquisition [Line Items]
Useful life (in years)	18 years
Developed technology \| GRAIL Inc
Business Acquisition [Line Items]
Finite-lived intangible assets acquired	$ 2,470
Trade name
Business Acquisition [Line Items]
Useful life (in years)	9 years
Trade name \| GRAIL Inc
Business Acquisition [Line Items]
Finite-lived intangible assets acquired	$ 40

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123413009&loc=d3e4845-128472

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

+ References

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=123455525&loc=d3e2207-128464

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