Fair Value Measurements - Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Millions	Jun. 28, 2020	Dec. 29, 2019
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Estimated Fair Value	$ 10,047	$ 4,368
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	11,174	17,305
Marketable securities	7,961	$ 1,982
Total cash, cash equivalents and current marketable securities, Carrying Amount	19,134
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	19,135
Held-to-maturity Securities
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	9,088
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	9,088
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	7,680
Marketable securities	1,408
Held-to-maturity Securities \| Cash
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	2,215
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	2,215
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	2,215
Held-to-maturity Securities \| Non-U.S. sovereign securities(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	655
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	655
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	225
Marketable securities	430
Held-to-maturity Securities \| U.S. reverse repurchase agreements
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	2,372
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	2,372
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	2,372
Marketable securities	0
Held-to-maturity Securities \| Other reverse repurchase agreements
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	460
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	460
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	460
Held-to-maturity Securities \| Corporate debt securities(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	1,279
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	1,279
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	301
Marketable securities	978
Held-to-maturity Securities \| Money market funds
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	1,528
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	1,528
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	1,528
Held-to-maturity Securities \| Time deposits(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	579
Held-to-maturity Securities, Unrecognized Gain	0
Held-to-maturity Securities, Unrecognized Loss	0
Held-to-maturity Securities - Estimated Fair Value	579
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	579
Available-for-sale Securities
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	10,046
Available-for-sale Securities, Unrecognized Gain	1
Available-for-sale Securities, Unrecognized Loss	0
Available-for-sale Securities - Estimated Fair Value	10,047
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	3,494
Marketable securities	6,553
Available-for-sale Securities \| Corporate debt securities(1)
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	255
Available-for-sale Securities, Unrecognized Gain	1
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	14
Marketable securities	242
Available-for-sale Securities \| US Treasury and Government [Member]
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	9,786
Available-for-sale Securities, Unrecognized Gain	0
Available-for-sale Securities, Unrecognized Loss	0
Available-for-sale Securities - Estimated Fair Value	9,786
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	3,480
Marketable securities	$ 6,306

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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