Carrying Amounts and Classification of Assets and Liabilities Included in Consolidated Balance Sheet Related to Consolidated VIE (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Current assets	$ 207	$ 270
Non-current assets	118	134
Total assets	325	404
Current liabilities	218	263
Non-current liabilities	6	4
Total liabilities	$ 224	$ 267

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Amount of consolidated variable interest entity's (VIE) assets, classified as current.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
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-URI http://asc.fasb.org/extlink&oid=108788376&loc=d3e5710-111685

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Amount of consolidated variable interest entity's (VIE) assets classified as noncurrent.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
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The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

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The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

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Amount of consolidated variable interest entity's (VIE) liabilities classified as current.

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Amount of consolidated variable interest entity's (VIE) liabilities, classified as noncurrent.

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