Employee Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2022

Retirement Benefits [Abstract]

Schedule of Changes in Benefit Obligation and Plan Assets

The following table sets forth, on an aggregated basis, changes in the benefit obligation and plan assets, the funded status and how the funded status is recognized on our consolidated balance sheets.    

Table 14.1: Changes in Benefit Obligation and Plan Assets

	Defined Pension  Benefits				Other Postretirement Benefits
(Dollars in millions)	2022		2021		2022		2021
Change in benefit obligation:
Accumulated benefit obligation as of January 1,	$	163	$	178	$	16	$	21
Service cost	1		1		0		0
Interest cost	4		4		0		0
Benefits paid	(11)		(12)		(1)		(2)
Actuarial loss (gain)	(29)		(8)		(3)		(3)
Accumulated benefit obligation as of December 31,	$	128	$	163	$	12	$	16
Change in plan assets:
Fair value of plan assets as of January 1,	$	273	$	274	$	6	$	6
Actual return on plan assets	(41)		10		(1)		1
Employer contributions	1		1		1		1
Benefits paid	(11)		(12)		(1)		(2)
Fair value of plan assets as of December 31,	$	222	$	273	$	5	$	6
Over (under) funded status as of December 31,	$	94	$	110	$	(7)	$	(10)

	Defined Pension  Benefits				Other Postretirement Benefits
(Dollars in millions)	2022		2021		2022		2021
Balance sheet presentation as of December 31,
Other assets	$	102	$	121	$	0	$	0
Other liabilities	(8)		(11)		(7)		(10)
Net amount recognized as of December 31,	$	94	$	110	$	(7)	$	(10)