Intangible Assets and Goodwill - Carrying Amount of Goodwill (Details) $ in Millions	6 Months Ended
Jun. 29, 2019 USD ($)
Goodwill Activity
Balance as of January 1, 2019	$ 1,514
Goodwill acquired	329
Purchase accounting adjustments	9
Balance as of June 29, 2019	1,852
Products and Systems Integration
Goodwill Activity
Balance as of January 1, 2019	722
Goodwill acquired	146
Purchase accounting adjustments	0
Balance as of June 29, 2019	868
Services and Software
Goodwill Activity
Balance as of January 1, 2019	792
Goodwill acquired	183
Purchase accounting adjustments	9
Balance as of June 29, 2019	$ 984

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 45
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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-Paragraph 16
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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