Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net income	$ 90	$ 410	$ 179
Other comprehensive income (loss):
Adjustment to pension liability	16	(10)	(7)
Income tax expense (benefit)	4	(2)	(2)
Adoption of ASU 2018-02			0
Other comprehensive income (loss)	12	(8)	(10)
Comprehensive income	102	402	169
AOCI Attributable to Parent [Member]
Net income	0	0	0
Other comprehensive income (loss):
Adoption of ASU 2018-02	$ 0	$ 0	$ (5)