Fair Value Measurements - Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Millions	Jul. 04, 2021	Jan. 03, 2021
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Estimated Fair Value	$ 13,056	$ 14,042
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	14,332	13,985
Marketable securities	10,974	$ 11,200
Total cash, cash equivalents and current marketable securities, Carrying Amount	25,306
Total cash, cash equivalents and current marketable securities, Unrecognized Gain	0
Total cash, cash equivalents and current marketable securities, Unrecognized Loss	0
Total cash, cash equivalents and current marketable securities, Estimated Fair Value	25,306
Held-to-maturity Securities
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	12,250
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	12,250
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	10,417
Marketable securities	1,833
Held-to-maturity Securities \| Cash
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	2,313
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	2,313
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	2,313
Marketable securities	0
Held-to-maturity Securities \| Non-U.S. sovereign securities(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	869
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	869
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	75
Marketable securities	794
Held-to-maturity Securities \| U.S. reverse repurchase agreements
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	2,091
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	2,091
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	2,091
Marketable securities	0
Held-to-maturity Securities \| Corporate debt securities(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	3,230
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	3,230
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	2,191
Marketable securities	1,039
Held-to-maturity Securities \| Money market funds
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	2,618
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	2,618
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	2,618
Marketable securities	0
Held-to-maturity Securities \| Time deposits(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	1,129
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	1,129
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	1,129
Marketable securities	0
Available-for-sale Securities
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	13,056
Available-for-sale Securities, Unrecognized Gain	0
Available-for-sale Securities, Unrecognized Loss	0
Available-for-sale Securities - Estimated Fair Value	13,056
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	3,915
Marketable securities	9,141
Available-for-sale Securities \| Non-U.S. sovereign securities(1)
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	1
Available-for-sale Securities, Unrecognized Gain	0
Available-for-sale Securities, Unrecognized Loss	0
Available-for-sale Securities - Estimated Fair Value	1
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	0
Marketable securities	1
Available-for-sale Securities \| Corporate debt securities(1)
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	257
Available-for-sale Securities, Unrecognized Gain	0
Available-for-sale Securities, Unrecognized Loss	0
Available-for-sale Securities - Estimated Fair Value	257
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	25
Marketable securities	232
Available-for-sale Securities \| U.S. Gov't securities
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	12,798
Available-for-sale Securities, Unrecognized Gain	0
Available-for-sale Securities, Unrecognized Loss	0
Available-for-sale Securities - Estimated Fair Value	12,798
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	3,890
Marketable securities	$ 8,908

Cash, Cash Equivalents, And Short-Term Investments, Accumulated Gross Unrealized Loss

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Cash, Cash Equivalents, and Short-term Investments, Estimated Fair Value

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Cash, Cash Equivalents, and Short-term Investments, Accumulated Gross Unrealized Gain

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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Amortized cost 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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Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

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