Retirement Plans (Tables)

3 Months Ended

Mar. 31, 2023

Retirement Benefits [Abstract]

Net period benefit cost for the pension and postretirement plans

The components of net periodic pension cost and net periodic benefit cost for the RAP and Postretirement Plan for the three months ended March 31, 2023 and 2022 were as follows:

	Three Months Ended Mar 31,
($ in thousands)	2023		2022
RAP
Service cost	$	796	$	923
Interest cost	2,686		1,772
Expected return on plan assets	(8,202)		(6,736)
Amortization of prior service cost	(63)		(63)
Amortization of actuarial loss	37		74
Total net periodic pension cost	$	(4,746)	$	(4,029)
Postretirement Plan
Interest cost	$	20	$	13
Amortization of prior service cost	(19)		(19)
Amortization of actuarial loss (gain)	(7)		—
Total net periodic benefit cost	$	(7)	$	(6)