Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Consolidated Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 387	$ (603)	$ 197
Other comprehensive (loss) income:
Foreign currency translation adjustments, net of tax	(62)	265	(107)
Other comprehensive (loss) income	(62)	265	(107)
Comprehensive income (loss)	$ 325	$ (338)	$ 90

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

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