Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ (750)	$ 161	$ (796)	$ 335
Other comprehensive income (loss), net of tax
Change in actuarial loss and other for postretirement and postemployment plans	(42)	(9)	(42)	(13)
Change in derivative hedges unrecognized loss	(4)	0	(26)	0
Other comprehensive loss	(46)	(9)	(68)	(13)
Comprehensive income (loss)	$ (796)	$ 152	$ (864)	$ 322

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

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