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Investments and Fair Value Measurements - Narrative (Details) |  |  |  |  | 3 Months Ended | 12 Months Ended |  |
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Aug. 18, 2021 USD ($) | Jan. 02, 2020 USD ($) | Apr. 25, 2019 USD ($) | Nov. 01, 2018 USD ($) $ / shares | Jan. 02, 2022 USD ($) | Jul. 04, 2021 USD ($) | Mar. 29, 2020 USD ($) | Dec. 29, 2019 USD ($) | Jan. 02, 2022 USD ($) venture | Jan. 03, 2021 USD ($) | Dec. 29, 2019 USD ($) | Feb. 28, 2021 USD ($) | Jul. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Marketable equity securities |  |  |  |  | $ 107,000,000 |  |  |  | $ 107,000,000 | $ 376,000,000 |  |  |
Strategic equity investments, without readily determinable fair values |  |  |  |  | 40,000,000 |  |  |  | 40,000,000 | 314,000,000 |  |  |
Gains on deconsolidation |  |  |  |  |  |  |  |  | 0 | 0 | $ 54,000,000 |  |
Gain (loss) on Helix contingent value right |  |  |  |  |  |  |  |  | 30,000,000 | 7,000,000 | (1,000,000) |  |
(Gain) loss on derivative assets related to terminated acquisition |  |  |  |  |  |  |  |  | (26,000,000) | 25,000,000 | 0 |  |
Measurement period adjustment |  |  |  |  |  |  |  |  | (5,000,000) |  |  |  |
Change in fair value of contingent consideration liabilities |  |  |  |  |  |  |  |  | 4,000,000 | 0 | 0 |  |
Business Combination, Contingent Consideration, Liability |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Change in estimated fair value |  |  |  |  |  |  |  |  | 4,000,000 |  |  |  |
Cash payments |  |  |  |  | (15,000,000) |  |  |  | 15,000,000 |  |  |  |
PacBio |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Cash |  |  |  | $ 1,200,000,000 |  |  |  |  |  |  |  |  |
Share price (in dollars per share) | $ / shares |  |  |  | $ 8.00 |  |  |  |  |  |  |  |  |
Payment of contingent consideration |  |  |  |  |  |  | $ 132,000,000 |  |  |  |  |  |
Equity or debt financing to be raised |  | $ 100,000,000 |  |  |  |  |  |  |  |  |  |  |
Derivative assets related to terminated acquisition |  |  |  |  |  |  |  | $ 10,000,000 |  | 40,000,000 | 10,000,000 |  |
PacBio | Reverse Termination Fee |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Payment of contingent consideration |  | $ 98,000,000 |  |  |  |  |  |  |  |  |  |  |
Period for contingent consideration to be repayable |  | 2 years |  |  |  |  |  |  |  |  |  |  |
PacBio | Continuation Advances |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Payment of contingent consideration |  |  |  |  |  |  | 34,000,000 | 18,000,000 |  |  |  |  |
Period for contingent consideration to be repayable |  | 2 years |  |  |  |  |  |  |  |  |  |  |
Maximum amount payable to PacBio |  | $ 52,000,000 |  |  |  |  |  |  |  |  |  |  |
PacBio | Selling, general and administrative |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
(Gain) loss on derivative assets related to terminated acquisition |  |  |  |  |  |  | $ 92,000,000 | $ 8,000,000 |  |  |  |  |
PacBio | Other Operating Income Expense |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Unrealized gain (loss) on derivatives |  |  |  |  |  |  |  |  |  | (25,000,000) |  |  |
GRAIL |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to acquire additional investments |  |  |  |  |  |  |  |  |  | 60,000,000 |  |  |
SB Northstar LP |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum amount payable to PacBio |  |  |  |  |  |  |  |  |  |  |  | $ 52,000,000 |
Series of Individually Immaterial Business Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value of contingent consideration |  |  |  |  |  | $ 14,000,000 |  |  |  |  |  |  |
Change in fair value of contingent consideration liabilities |  |  |  |  |  |  |  |  | (1,000,000) |  |  |  |
GRAIL Inc |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Cash | $ 2,862,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Measurement period adjustment |  |  |  |  | (5,000,000) |  |  |  |  |  |  |  |
Change in estimated fair value |  |  |  |  |  |  |  |  | 7,000,000 |  |  |  |
Fair value of contingent consideration | $ 757,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Change in fair value of contingent consideration liabilities |  |  |  |  | 5,000,000 |  |  |  | 3,000,000 |  |  |  |
Helix Holdings I, LLC |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Gains on deconsolidation |  |  | $ 39,000,000 |  |  |  |  |  |  |  |  |  |
Contingent value right |  |  | $ 30,000,000 |  |  |  |  |  |  |  |  |  |
Gain (loss) on Helix contingent value right |  |  |  |  |  |  |  |  | 30,000,000 | 7,000,000 | (1,000,000) |  |
PacBio | SB Northstar LP |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
(Gain) loss on derivative assets related to terminated acquisition |  |  |  |  |  |  |  |  | $ (26,000,000) |  |  |  |
PacBio | SB Northstar LP | Convertible Senior Notes |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of notes outstanding |  |  |  |  |  |  |  |  |  |  |  | $ 900,000,000 |
Venture Capital Investment Fund (the Fund) |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Number of venture capital investment funds | venture |  |  |  |  |  |  |  |  | 2 |  |  |  |
Equity method investments |  |  |  |  | 173,000,000 |  |  |  | $ 173,000,000 | 104,000,000 |  |  |
Unrealized gain on equity method investments |  |  |  |  |  |  |  |  | 55,000,000 | 20,000,000 | 9,000,000 |  |
Venture Capital Investment Fund (the Fund), One |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Commitment in new venture capital investment fund |  |  |  |  | 100,000,000 |  |  |  | 100,000,000 |  |  |  |
Remaining capital commitment |  |  |  |  | 20,000,000 |  |  |  | 20,000,000 |  |  |  |
Venture Capital Investment Fund (the Fund), Two |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Commitment in new venture capital investment fund |  |  |  |  | 150,000,000 |  |  |  | 150,000,000 |  |  |  |
Remaining capital commitment |  |  |  |  | $ 118,000,000 |  |  |  | 118,000,000 |  |  |  |
Investee |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue from transactions with strategic investees |  |  |  |  |  |  |  |  | $ 74,000,000 | 62,000,000 | $ 71,000,000 |  |
Variable Interest Entity, Not Primary Beneficiary | GRAIL |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Net assets |  |  |  |  |  |  |  |  |  | $ 250,000,000 |  |  |
Variable Interest Entity, Primary Beneficiary | Helix Holdings I, LLC |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Absorbed Helix's losses percentage |  |  |  |  |  |  |  |  |  |  | 50.00% |  |
Variable Interest Entity, Primary Beneficiary | Helix Holdings I, LLC |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Equity ownership interest percentage |  |  |  |  |  |  |  |  |  |  |  |  | 50.00%

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