Pension and Other Post-Retirement Benefits - Pension and Post-Retirement Plans (Details) - Pension Benefits - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Components of net periodic pension expense (credit):
Interest cost	$ 1	$ 1	$ 2	$ 2
Expected return on plan assets	(4)	(4)	(8)	(8)
Amortization of net actuarial loss	1	2	1	4
Net periodic (credit) expense	$ (2)	$ (1)	$ (5)	$ (2)