Revenues - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018	Dec. 31, 2018
Capitalized Contract Cost [Line Items]
Increase driven by payments received or due in advance of satisfying performance obligations	$ 432		$ 432		$ 382
Revenue recognized that was included in contract liability	41	$ 32	168	$ 152
Prepaid expenses and other current assets
Capitalized Contract Cost [Line Items]
Contract assets recorded in prepaids and other current assets	$ 9		$ 9		$ 5

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No definition available.

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130531-203044

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130531-203044

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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