Fair Value Measurements - Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Millions	Apr. 04, 2021	Jan. 03, 2021
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Estimated Fair Value	$ 14,493	$ 14,042
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	12,671	13,985
Marketable securities	11,948	$ 11,200
Total cash, cash equivalents and current marketable securities, Carrying Amount	24,618
Total cash, cash equivalents and current marketable securities, Unrecognized Gain	1
Total cash, cash equivalents and current marketable securities, Unrecognized Loss	0
Total cash, cash equivalents and current marketable securities, Estimated Fair Value	24,619
Held-to-maturity Securities
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	10,126
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	10,126
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	8,377
Marketable securities	1,749
Held-to-maturity Securities \| Cash
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	2,247
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	2,247
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	2,247
Held-to-maturity Securities \| Non-U.S. sovereign securities(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	400
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	400
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	0
Marketable securities	400
Held-to-maturity Securities \| U.S. reverse repurchase agreements
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	1,199
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	1,199
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	1,199
Marketable securities	0
Held-to-maturity Securities \| Other reverse repurchase agreements
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	0
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	0
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	0
Held-to-maturity Securities \| Corporate debt securities(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	3,239
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	3,239
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	1,890
Marketable securities	1,349
Held-to-maturity Securities \| Money market funds
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	2,094
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	2,094
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	2,094
Held-to-maturity Securities \| Time deposits(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	947
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	947
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	947
Available-for-sale Securities
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	14,492
Available-for-sale Securities, Unrecognized Gain	1
Available-for-sale Securities, Unrecognized Loss	0
Available-for-sale Securities - Estimated Fair Value	14,493
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	4,294
Marketable securities	10,199
Available-for-sale Securities \| Non-U.S. sovereign securities(1)
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	8
Available-for-sale Securities, Unrecognized Gain	0
Available-for-sale Securities, Unrecognized Loss	0
Available-for-sale Securities - Estimated Fair Value	8
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	1
Marketable securities	7
Available-for-sale Securities \| Corporate debt securities(1)
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	256
Available-for-sale Securities, Unrecognized Gain	0
Available-for-sale Securities, Unrecognized Loss	0
Available-for-sale Securities - Estimated Fair Value	256
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	25
Marketable securities	231
Available-for-sale Securities \| U.S. Gov't securities
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	14,228
Available-for-sale Securities, Unrecognized Gain	1
Available-for-sale Securities, Unrecognized Loss	0
Available-for-sale Securities - Estimated Fair Value	14,229
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	4,268
Marketable securities	$ 9,961

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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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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