Fair Value Measurements - Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Millions	Sep. 27, 2020	Dec. 29, 2019
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Estimated Fair Value	$ 13,391	$ 4,368
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	18,965	17,305
Marketable securities	11,816	$ 1,982
Total cash, cash equivalents and current marketable securities, Carrying Amount	30,780
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	30,781
Held-to-maturity Securities
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	17,390
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	17,390
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	15,471
Marketable securities	1,919
Held-to-maturity Securities \| Cash
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	2,231
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	2,231
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	2,231
Held-to-maturity Securities \| Non-U.S. sovereign securities(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	647
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	647
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	0
Marketable securities	647
Held-to-maturity Securities \| U.S. reverse repurchase agreements
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	3,094
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	3,094
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	3,094
Marketable securities	0
Held-to-maturity Securities \| Other reverse repurchase agreements
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	430
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	430
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	430
Held-to-maturity Securities \| Corporate debt securities(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	1,843
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	1,843
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	571
Marketable securities	1,272
Held-to-maturity Securities \| Money market funds
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	8,485
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	8,485
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	8,485
Held-to-maturity Securities \| Time deposits(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	660
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	660
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	660
Available-for-sale Securities
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	13,390
Available-for-sale Securities, Unrecognized Gain	1
Available-for-sale Securities, Unrecognized Loss	0
Available-for-sale Securities - Estimated Fair Value	13,391
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	3,494
Marketable securities	9,897
Available-for-sale Securities \| Non-U.S. sovereign securities(1)
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	10
Available-for-sale Securities, Unrecognized Gain	0
Available-for-sale Securities, Unrecognized Loss	0
Available-for-sale Securities - Estimated Fair Value	10
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	0
Marketable securities	10
Available-for-sale Securities \| Corporate debt securities(1)
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	247
Available-for-sale Securities, Unrecognized Gain	0
Available-for-sale Securities, Unrecognized Loss	0
Available-for-sale Securities - Estimated Fair Value	247
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	11
Marketable securities	236
Available-for-sale Securities \| US Treasury and Government [Member]
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	13,133
Available-for-sale Securities, Unrecognized Gain	1
Available-for-sale Securities, Unrecognized Loss	0
Available-for-sale Securities - Estimated Fair Value	13,134
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	3,483
Marketable securities	$ 9,651

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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