Consolidated Statements Of Comprehensive Loss - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Consolidated Statements Of Comprehensive Loss [Abstract]
Net loss	$ (662)	$ (27)	$ (737)	$ (213)
Pension settlement costs, net of tax	11		36
Other comprehensive income, net of tax	(14)	5	22	11
Net current-period other comprehensive income	(3)	5	58	11
Comprehensive loss	$ (665)	$ (22)	$ (679)	$ (202)

Net Current Period Other Comprehensive Income Excluding Pension Settlement (Net of Tax

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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.

+ References

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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, of increase (decrease) to other comprehensive income from settlement and curtailment gain (loss) of defined benefit plan.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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