Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Net income	$ 179	$ 211	$ 262
Other comprehensive (loss) income :
Adjustment to pension liability	(7)	1	(7)
Income tax (benefit) expense	(2)	0	(3)
Adoption of ASU 2018-02	0
Other comprehensive (loss) income	(10)	1	(4)
Comprehensive income	169	212	258
AOCI Attributable to Parent [Member]
Net income	0	0	0
Other comprehensive (loss) income :
Adoption of ASU 2018-02	$ (5)	$ 0	$ 0

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