Tax - Tax Paid - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current tax expense (income) and adjustments for current tax of prior periods [abstract]
Net tax paid	$ 68	$ 172	$ 130
Net tax paid in operating activities	66	147	130
Net tax paid in investing activities	$ 2	$ 25	$ 0

No definition available.

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- Definition

The cash flows from income taxes paid or refunded.

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- Definition

The cash flows from income taxes paid or refunded, classified as investing activities. [Refer: Income taxes paid (refund)]

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- Definition

The cash flows from income taxes paid or refunded, classified as operating activities. [Refer: Income taxes paid (refund)]

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