Retirement Plans (Tables)

9 Months Ended

Sep. 30, 2023

Retirement Benefits, Description [Abstract]

Schedule of Components of Net Periodic Benefit Cost

The components of net periodic benefit cost for the three and nine months ended September 30 were as follows:

COMPONENTS OF NET PERIODIC BENEFIT COST
	Three months ended September 30,				Nine months ended September 30,
(Dollars in millions)	2023		2022		2023		2022
Components of net periodic benefit cost
Interest cost	$	10	$	5	$	26	$	15
Expected return on plan assets	(9)		(6)		(25)		(18)
Amortization of unrecognized:
Actuarial (gain) loss	3		4		9		8
Net periodic benefit cost	$	4	$	3	$	10	$	5