Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (317)	$ 165	$ (1,113)	$ 500
Other comprehensive income (loss), net of tax
Change in actuarial gain (loss) and other for postretirement and postemployment plans	9	38	(33)	25
Change in derivative hedges unrecognized gain (loss)	11	0	(15)	0
Foreign currency translation adjustment related to sale of U.K. business	0	23	0	23
Other	0	1	0	1
Other comprehensive income (loss)	20	62	(48)	49
Comprehensive income (loss)	$ (297)	$ 227	$ (1,161)	$ 549

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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.

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