CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - 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 (loss)		$ (880)	$ 138	$ (2,427)	$ 732
Change in value of pension and other postretirement liabilities:
Amortization of prior service cost and net loss included in net periodic pension cost	[1]	0	4	0	4
Comprehensive income (loss)		$ (880)	$ 142	$ (2,427)	$ 736

[1] Tax benefits for the three months ended June 30, 2020 were immaterial. Net of $1 million in tax benefits for the six months ended June 30, 2020 and the three and six months ended June 30, 2019, respectively. In 2019, primarily related to settlement of pension assets.