Fair Value Measurements - Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Millions	Sep. 29, 2019	Dec. 30, 2018
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Estimated Fair Value	$ 4,327	$ 9,734
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	16,249	18,107
Marketable securities	1,696	$ 1,580
Cash, Cash Equivalents, and Short-term Investments	17,944
Cash, Cash Equivalents, and Short-term Investments, Accumulated Gross Unrealized Gain	1
Cash, Cash Equivalents, And Short-Term Investments, Estimated Fair Value	17,945
Held-to-maturity Securities
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	13,618
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Held-to-maturity Securities - Estimated Fair Value	13,618
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	13,040
Marketable securities	578
Held-to-maturity Securities \| Cash
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	2,667
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Held-to-maturity Securities - Estimated Fair Value	2,667
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	2,667
Held-to-maturity Securities \| Other sovereign securities(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	709
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Held-to-maturity Securities - Estimated Fair Value	709
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	619
Marketable securities	90
Held-to-maturity Securities \| U.S. reverse repurchase agreements
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	6,182
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Held-to-maturity Securities - Estimated Fair Value	6,182
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	6,182
Marketable securities
Held-to-maturity Securities \| Other reverse repurchase agreements
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	241
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Held-to-maturity Securities - Estimated Fair Value	241
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	241
Held-to-maturity Securities \| Corporate debt securities(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	1,647
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Held-to-maturity Securities - Estimated Fair Value	1,647
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	1,159
Marketable securities	488
Held-to-maturity Securities \| Money market funds
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	1,481
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Held-to-maturity Securities - Estimated Fair Value	1,481
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	1,481
Held-to-maturity Securities \| Time deposits(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	691
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Held-to-maturity Securities - Estimated Fair Value	691
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	691
Available-for-sale Securities
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	4,326
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1
Available-for-sale Securities - Estimated Fair Value	4,327
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	3,209
Marketable securities	1,118
Available-for-sale Securities \| Other sovereign securities(1)
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	4
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0
Available-for-sale Securities - Estimated Fair Value	4
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	0
Marketable securities	4
Available-for-sale Securities \| Corporate debt securities(1)
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	272
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0
Available-for-sale Securities - Estimated Fair Value	272
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	14
Marketable securities	258
Available-for-sale Securities \| US Treasury and Government [Member]
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	4,050
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1
Available-for-sale Securities - Estimated Fair Value	4,051
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	3,195
Marketable securities	$ 856

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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