Investments and Fair Value Measurements - Summary of Hierarchy for Assets and Liabilities Measured at Fair Value Recurring Basis (Details) - USD ($) $ in Millions	Jan. 02, 2022	Jan. 03, 2021
Assets:
Available-for-sale securities		$ 1,286
Marketable equity securities	$ 107	376
Debt securities in government-sponsored entities
Assets:
Available-for-sale securities		10
Corporate debt securities
Assets:
Available-for-sale securities		445
U.S. Treasury securities
Assets:
Available-for-sale securities		831
Fair value, Measurements, Recurring
Assets:
Marketable equity securities	107	376
Helix contingent value right	65	35
Derivative assets related to terminated acquisition	0	26
Deferred compensation plan assets	60	55
Total assets measured at fair value	920	3,290
Liabilities:
Contingent consideration liabilities	615	0
Deferred compensation plan liability	56	51
Total liabilities measured at fair value	671	51
Fair value, Measurements, Recurring \| Money market funds (cash equivalents)
Assets:
Money market funds (cash equivalents)	688	1,512
Fair value, Measurements, Recurring \| Debt securities in government-sponsored entities
Assets:
Available-for-sale securities	0	10
Fair value, Measurements, Recurring \| Corporate debt securities
Assets:
Available-for-sale securities	0	445
Fair value, Measurements, Recurring \| U.S. Treasury securities
Assets:
Available-for-sale securities	0	831
Fair value, Measurements, Recurring \| Level 1
Assets:
Marketable equity securities	107	376
Helix contingent value right	0	0
Derivative assets related to terminated acquisition	0	0
Deferred compensation plan assets	0	0
Total assets measured at fair value	795	2,719
Liabilities:
Contingent consideration liabilities	0	0
Deferred compensation plan liability	0	0
Total liabilities measured at fair value	0	0
Fair value, Measurements, Recurring \| Level 1 \| Money market funds (cash equivalents)
Assets:
Money market funds (cash equivalents)	688	1,512
Fair value, Measurements, Recurring \| Level 1 \| Debt securities in government-sponsored entities
Assets:
Available-for-sale securities	0	0
Fair value, Measurements, Recurring \| Level 1 \| Corporate debt securities
Assets:
Available-for-sale securities	0	0
Fair value, Measurements, Recurring \| Level 1 \| U.S. Treasury securities
Assets:
Available-for-sale securities	0	831
Fair value, Measurements, Recurring \| Level 2
Assets:
Marketable equity securities	0	0
Helix contingent value right	0	0
Derivative assets related to terminated acquisition	0	0
Deferred compensation plan assets	60	55
Total assets measured at fair value	60	510
Liabilities:
Contingent consideration liabilities	0	0
Deferred compensation plan liability	56	51
Total liabilities measured at fair value	56	51
Fair value, Measurements, Recurring \| Level 2 \| Money market funds (cash equivalents)
Assets:
Money market funds (cash equivalents)	0	0
Fair value, Measurements, Recurring \| Level 2 \| Debt securities in government-sponsored entities
Assets:
Available-for-sale securities	0	10
Fair value, Measurements, Recurring \| Level 2 \| Corporate debt securities
Assets:
Available-for-sale securities	0	445
Fair value, Measurements, Recurring \| Level 2 \| U.S. Treasury securities
Assets:
Available-for-sale securities	0	0
Fair value, Measurements, Recurring \| Level 3
Assets:
Marketable equity securities	0	0
Helix contingent value right	65	35
Derivative assets related to terminated acquisition	0	26
Deferred compensation plan assets	0	0
Total assets measured at fair value	65	61
Liabilities:
Contingent consideration liabilities	615	0
Deferred compensation plan liability	0	0
Total liabilities measured at fair value	615	0
Fair value, Measurements, Recurring \| Level 3 \| Money market funds (cash equivalents)
Assets:
Money market funds (cash equivalents)	0	0
Fair value, Measurements, Recurring \| Level 3 \| Debt securities in government-sponsored entities
Assets:
Available-for-sale securities	0	0
Fair value, Measurements, Recurring \| Level 3 \| Corporate debt securities
Assets:
Available-for-sale securities	0	0
Fair value, Measurements, Recurring \| Level 3 \| U.S. Treasury securities
Assets:
Available-for-sale securities	$ 0	$ 0

Contingent Value Right, Fair Value Disclosure

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of liability recognized arising from contingent consideration in a business combination.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value of financial and nonfinancial obligations.

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