Fair Value Measurements - Summary of Activity Related to Equity Investments (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Dec. 30, 2018
Equity Investment [Roll Forward]
Non Current Other Assets	$ 5,159	$ 4,182
Equity Securities \| Equity Investments with readily determinable value
Equity Investment [Roll Forward]
Carrying value, beginning of period	511
Changes in Fair Value Reflected in Net Income	143
Sales/ Purchases/Other	176
Carrying value, end of period	830
Non Current Other Assets	830
Equity Securities \| Equity Investments without readily determinable value
Equity Investment [Roll Forward]
Carrying value, beginning of period	681
Changes in Fair Value Reflected in Net Income	4
Sales/ Purchases/Other	13
Carrying value, end of period	698
Non Current Other Assets	$ 698

Equity Investment [Roll Forward]

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Equity Investments, Increase (Decrease) from Acquisition (Sale) During Period

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Amount of addition (reduction) to the amount at which an instrument classified in shareholders' equity could be incurred (settled) in a current transaction between willing parties.

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Amount of investment in equity security without readily determinable fair value.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
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-Section 50
-Paragraph 3
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Amount of investment in marketable security, classified as noncurrent.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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