Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Consolidated Statement of Comprehensive Income [Abstract]
Net income	$ 129	$ 59
Other comprehensive income:
Foreign currency translation adjustments, net of tax	10	308
Other comprehensive income	10	308
Comprehensive income	$ 139	$ 367

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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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, attributable to parent entity.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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