Income Taxes - Summary of Tax Provisions (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Pretax income at estimated annual effective income tax rate before discrete items	$ 67	$ 53
Interim period treatment of operational losses in foreign jurisdictions for which no tax benefit is recognized	2	1
Other discrete items	1	2
Provision for income taxes	$ 70	$ 56

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments.

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