Background and Basis of Presentation - Additional Information (Detail) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017 USD ($) Country shares	Sep. 30, 2016 shares	Sep. 30, 2017 USD ($) Segment Country shares	Sep. 30, 2016 shares
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Number of reportable segments \| Segment			2
Number of countries in which entity operates \| Country	100		100
Anti-dilutive shares excluded from calculation of earning per share under compensation plan \| shares	4,141,427	472,433	4,349,803	1,176,950
Uncommitted accounts receivable	$ 67		$ 67
Accounts receivable outstanding	$ 56		$ 56

Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(5))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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The number of countries in which the entity operates as of balance sheet date.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The face amount of accounts receivable that will be sold to other entities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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