Goodwill and Acquired Intangible Assets - Goodwill by Operating Segment (Detail) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 395
Reassignment of Goodwill	0
Currency translation adjustments	1
Ending balance	396
Americas
Goodwill [Roll Forward]
Beginning balance	253
Reassignment of Goodwill	0
Currency translation adjustments	0
Ending balance	253
International
Goodwill [Roll Forward]
Beginning balance	142
Reassignment of Goodwill	(142)
Currency translation adjustments	0
Ending balance	0
EMEA
Goodwill [Roll Forward]
Beginning balance	0
Reassignment of Goodwill	88
Currency translation adjustments	0
Ending balance	88
APAC
Goodwill [Roll Forward]
Beginning balance	0
Reassignment of Goodwill	54
Currency translation adjustments	1
Ending balance	$ 55

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits 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 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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- Definition

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
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e961-128460

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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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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