Consolidated Statements Of Comprehensive Loss - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Consolidated Statements Of Comprehensive Loss [Abstract]
Net loss	$ (402)	$ (5,911)	$ (643)
Other comprehensive loss, net of tax	(105)	(108)	(97)
Comprehensive loss	$ (507)	$ (6,019)	$ (740)

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

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