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Fair Value Measurements - Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 30, 2018	Jul. 01, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Estimated Fair Value	$ 2,767	$ 9,734
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	14,376	18,107	$ 17,569	$ 17,824
Marketable securities	902	$ 1,580
Held-to-maturity Securities
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	12,511
Held-to-maturity Securities - Estimated Fair Value	12,511
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	12,511
Marketable securities	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Held-to-maturity Securities \| Cash
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	2,615
Held-to-maturity Securities - Estimated Fair Value	2,615
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	2,615
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Held-to-maturity Securities \| Other sovereign securities(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	380
Held-to-maturity Securities - Estimated Fair Value	380
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	380
Marketable securities
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Held-to-maturity Securities \| U.S. reverse repurchase agreements
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	7,014
Held-to-maturity Securities - Estimated Fair Value	7,014
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	7,014
Marketable securities
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Held-to-maturity Securities \| Other reverse repurchase agreements
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	219
Held-to-maturity Securities - Estimated Fair Value	219
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	219
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Held-to-maturity Securities \| Corporate debt securities(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	264
Held-to-maturity Securities - Estimated Fair Value	264
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	264
Marketable securities
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Held-to-maturity Securities \| Money market funds
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	1,368
Held-to-maturity Securities - Estimated Fair Value	1,368
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	1,368
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Held-to-maturity Securities \| Time deposits(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	651
Held-to-maturity Securities - Estimated Fair Value	651
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	651
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Available-for-sale Securities
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	2,766
Available-for-sale Securities - Estimated Fair Value	2,767
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	1,865
Marketable securities	902
Available-for-sale Securities \| Other sovereign securities(1)
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	0
Available-for-sale Securities - Estimated Fair Value	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	0
Marketable securities	0
Available-for-sale Securities \| Corporate debt securities(1)
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	265
Available-for-sale Securities - Estimated Fair Value	265
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	20
Marketable securities	245
Available-for-sale Securities \| US Treasury and Government [Member]
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	2,501
Available-for-sale Securities - Estimated Fair Value	2,502
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	1,845
Marketable securities	$ 657