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Summary of Significant Accounting Policies - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($) ReportingUnit	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Inventories, net	$ 602	$ 590
Net of inventory reserves	$ 28	40
Number of reporting units | ReportingUnit	5
Foreign currency transaction losses	$ 2	$ 2	$ 1
Customer Concentration Risk [Member] | Sales Revenue, Net [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of revenue	10.00%

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Summary of significant accounting policies.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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