Fair Value Measurements - Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 30, 2018	Apr. 01, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Estimated Fair Value	$ 4,673	$ 9,734
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	14,734	18,107	$ 14,639	$ 17,824
Marketable securities	602	$ 1,580
Held-to-maturity Securities
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	10,663
Held-to-maturity Securities - Estimated Fair Value	10,663
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	10,563
Marketable securities	100
Held-to-maturity Securities | Cash
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	2,778
Held-to-maturity Securities - Estimated Fair Value	2,778
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	2,778
Held-to-maturity Securities | Other sovereign securities(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	190
Held-to-maturity Securities - Estimated Fair Value	190
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	190
Marketable securities
Held-to-maturity Securities | U.S. reverse repurchase agreements
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	2,068
Held-to-maturity Securities - Estimated Fair Value	2,068
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	2,068
Marketable securities
Held-to-maturity Securities | Other reverse repurchase agreements
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	350
Held-to-maturity Securities - Estimated Fair Value	350
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	350
Held-to-maturity Securities | Corporate debt securities(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	549
Held-to-maturity Securities - Estimated Fair Value	549
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	449
Marketable securities	100
Held-to-maturity Securities | Money market funds
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	4,195
Held-to-maturity Securities - Estimated Fair Value	4,195
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	4,195
Held-to-maturity Securities | Time deposits(1)
Debt Securities, Held-to-maturity [Abstract]
Held-to-maturity Securities - Carrying Amount	533
Held-to-maturity Securities - Estimated Fair Value	533
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	533
Available-for-sale Securities
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	4,673
Available-for-sale Securities - Estimated Fair Value	4,673
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	4,171
Marketable securities	502
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 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	261
Available-for-sale Securities - Estimated Fair Value	261
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	28
Marketable securities	233
Available-for-sale Securities | US Treasury and Government [Member]
Debt Securities, Available-for-sale [Abstract]
Available-for-sale Securities - Carrying Amount	4,412
Available-for-sale Securities - Estimated Fair Value	4,412
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Cash and Cash Equivalents	4,143
Marketable securities	$ 269