Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Net income (loss)	$ (2,942)	$ (1,129)	$ 1,657
Other comprehensive income (loss), net of income taxes:
Defined benefit and other postretirement plans adjustments	(24)	(11)	131
Other	24	3	(17)
Other comprehensive income (loss), net of income taxes	0	(8)	114
Comprehensive income (loss)	(2,942)	(1,137)	1,771
Comprehensive income attributable to noncontrolling interest	(3)	(2)	(1)
Comprehensive income (loss) attributable to company shareholders	$ (2,945)	$ (1,139)	$ 1,770