Changes in Accumulated Other Comprehensive Income (Details) - Summary of Changes in Accumulated Other Comprehensive Income - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance	$ 6	$ (33)	$ (8)	$ (39)
Beginning Balance Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, After Tax	1	3	1	3
Beginning Balance Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	5	(36)	(9)	(42)
Other comprehensive income before reclassifications, net of tax	(16)	9	(2)	15
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	0	0	0	0
Foreign currency translation adjustments	(16)	9	(2)	15
Ending Balance Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, After Tax	1	3	1	3
Ending Balance Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	(11)	(27)	(11)	(27)
Ending Balance	$ (10)	$ (24)	$ (10)	$ (24)

Changes in Accumulated Other Comprehensive Income [Roll Forward]

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- Definition

Other comprehensive income before reclassifications, net of tax

+ References

No definition available.

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- Definition

Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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- Definition

Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

+ References

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- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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- Definition

Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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- Definition

Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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