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Acquisitions, Goodwill and Intangible Assets - Narrative (Details) - USD ($) $ / shares in Units, shares in Millions |  |  | 1 Months Ended | 3 Months Ended | 5 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | ---
Aug. 18, 2021 | Aug. 17, 2021 | Dec. 31, 2021 | Jan. 02, 2022 | Oct. 03, 2021 | Jul. 04, 2021 | Jan. 02, 2022 | Jan. 02, 2022 | Jan. 03, 2021 | Dec. 29, 2019
Goodwill [Line Items] |  |  |  |  |  |  |  |  |  |
Change in fair value of contingent consideration liabilities |  |  |  |  |  |  |  | $ (4,000,000) | $ 0 | $ 0
Goodwill, purchase accounting adjustments |  |  |  | $ 6,000,000 |  |  |  | 15,000,000 |  |
Gain on exchange of GRAIL contingent value rights |  |  |  |  |  |  |  | 86,000,000 | 0 | 0
Gain on previously held investment in GRAIL |  |  |  |  |  |  |  | $ 899,000,000 | 0 | 0
Share price (in dollars per share) |  |  | $ 380.44 |  |  |  |  |  |  |
Expected dividend yield |  |  |  |  |  |  |  | 0.00% |  |
Goodwill impairment |  |  |  |  |  | $ 0 |  |  |  |
Goodwill |  |  |  | 7,113,000,000 |  |  | $ 7,113,000,000 | $ 7,113,000,000 | 897,000,000 | $ 824,000,000
Developed technology |  |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |  |
Weighted-average useful lives (in years) |  |  |  |  |  |  |  | 18 years |  |
GRAIL Inc |  |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |  |
Change in fair value of contingent consideration liabilities |  |  |  | (5,000,000) |  |  |  | $ (3,000,000) |  |
Increase (decrease) in previously held investment in GRAIL |  |  |  | (1,000,000) |  |  |  |  |  |
Goodwill, purchase accounting adjustments |  |  |  |  |  |  | 15,000,000 |  |  |
Business acquisition, common stock issued (in shares) | 9.8 |  |  |  |  |  |  |  |  |
Contingent value right, terms | 12 years |  |  |  |  |  |  |  |  |
Contingent consideration liabilities |  |  | $ 145,000,000 | 615,000,000 |  |  | 615,000,000 | 615,000,000 |  |
Contingent value rights exchanged |  |  | 73.0 |  |  |  |  |  |  |
Payment for contingent consideration |  |  | $ 57,000,000 |  |  |  |  |  |  |
Number of shares issued in exchange for contingent consideration |  |  | 2.0 |  |  |  |  |  |  |
Gain on exchange of GRAIL contingent value rights |  |  | $ 86,000,000 |  |  |  |  |  |  |
Business combination, consideration transferred for contingent consideration transferred |  |  | $ 59,000,000 |  |  |  |  |  |  |
Contingent consideration, noncurrent |  |  |  | 614,000,000 |  |  | 614,000,000 | 614,000,000 |  |
Equity ownership percentage | 12.00% |  |  |  |  |  |  |  |  |
Equity investment | $ 1,100,000,000 |  |  |  |  |  |  |  |  |
Gain on previously held investment in GRAIL |  |  |  |  |  |  |  | 899,000,000 |  |
Purchase price related to fair value of equity awards attributable to pre-combination service | 69,000,000 |  |  |  |  |  |  |  |  |
Share-based payment arrangement, accelerated cost |  |  |  |  |  |  |  | 615,000,000 |  |
Fair value of replacement awards | $ 48,000,000 |  |  |  |  |  |  |  |  |
Share price (in dollars per share) | $ 510.61 |  |  |  |  |  |  |  |  |
Risk-free interest rate, minimum | 0.17% |  |  |  |  |  |  |  |  |
Risk-free interest rate, maximum | 0.28% |  |  |  |  |  |  |  |  |
Expected volatility, minimum | 40.00% |  |  |  |  |  |  |  |  |
Expected volatility, maximum | 43.00% |  |  |  |  |  |  |  |  |
Expected dividend yield | 0.00% |  |  |  |  |  |  |  |  |
Weighted average acquisition-date fair value per share (in dollars per share) | $ 424.39 |  |  |  |  |  |  |  |  |
Acquisition related costs |  |  |  |  |  |  |  | 156,000,000 |  |
Business combination, continuation payments |  | $ 35,000,000 |  |  |  |  |  |  |  |
Goodwill | $ 6,082,000,000 |  |  | $ 6,097,000,000 |  |  | $ 6,097,000,000 | 6,097,000,000 |  |
GRAIL Inc | Selling, general and administrative |  |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |  |
Business combination, continuation payments |  |  |  |  |  |  |  | 245,000,000 | 35,000,000 |
GRAIL Inc | Minimum |  |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |  |
Expected term | 1 year 7 months 6 days |  |  |  |  |  |  |  |  |
GRAIL Inc | Maximum |  |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |  |
Expected term | 2 years 2 months 12 days |  |  |  |  |  |  |  |  |
GRAIL Inc | Payment Rights Of One Billion Each Twelve Years |  |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |  |
Contingent payment rights, first percentage | 2.50% |  |  |  |  |  |  |  |  |
Business acquisition, contingent value rights, revenue threshold | $ 1,000,000,000 |  |  |  |  |  |  |  |  |
GRAIL Inc | Payment Rights Of Above One Billion Each Twelve Years |  |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |  |
Business acquisition, contingent value rights, revenue threshold | $ 1,000,000,000 |  |  |  |  |  |  |  |  |
Contingent payment rights, second percentage | 9.00% |  |  |  |  |  |  |  |  |
Series of Individually Immaterial Business Acquisitions |  |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |  |
Change in fair value of contingent consideration liabilities |  |  |  |  |  |  |  | $ 1,000,000 |  |
Series of Individually Immaterial Business Acquisitions | Developed technology |  |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |  |
Value of intangible assets acquired |  |  |  |  | $ 28,000,000 |  |  |  | $ 26,000,000 |
Weighted-average useful lives (in years) |  |  |  |  | 10 years |  |  |  | 10 years |
Series of Individually Immaterial Business Acquisitions | In-process research and development (IPR&D) |  |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |  |
Indefinite-lived intangible assets acquired |  |  |  |  |  | $ 35,000,000 |  |  |  |

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- Definition 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. + References 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 + Details
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- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=123586518&loc=d3e1043-128460 + Details
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- Definition In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g)(2) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details
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- Definition The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References No definition available. + Details
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- Definition The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References No definition available. + Details
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