Retirement Plans (Tables)

3 Months Ended

Mar. 31, 2024

Retirement Benefits, Description [Abstract]

Schedule of Components of Net Periodic Benefit Cost

The components of net periodic benefit cost for the three months ended March 31 were as follows:

COMPONENTS OF NET PERIODIC BENEFIT COST
	Three months ended March 31,
(Dollars in millions)	2024		2023
Components of net periodic benefit cost
Interest cost	$	8	$	8
Expected return on plan assets	(8)		(8)
Amortization of unrecognized:
Actuarial (gain) loss	3		3
Net periodic benefit cost	$	3	$	3