CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 96	$ 171	$ (30)
Defined benefit pension/other postretirement plans:
Pension/other postretirement liability adjustment, net	2	(20)	5
Amortization of net actuarial loss	0	1	0
Other comprehensive income (loss), net of tax	2	(19)	5
Comprehensive income (loss)	$ 98	$ 152	$ (25)