Retirement Plans and Other Postretirement Benefits (Tables)

9 Months Ended

Sep. 30, 2021

Retirement Benefits [Abstract]

Components of Net Periodic Benefit Cost (Income)

Information with respect to the Retirement Plans and Other Postretirement Benefits follows: 

	Three Months Ended September 30,
	2021		2020		2021		2020
(Dollars in thousands)	Retirement Plans				Other Post Retirement Benefits
Service cost	$	164	$	117	$	36	$	27
Interest cost	366		425		21		23
Expected return on plan assets	(946)		(816)		—		—
Amortization of net actuarial loss	318		300		11		7
Net periodic benefit (income) cost	$	(98)	$	26	$	68	$	57

	Nine Months Ended September 30,
	2021		2020		2021		2020
(Dollars in thousands)	Retirement Plans				Other Post Retirement Benefits
Service cost	$	425	$	350	$	107	$	82
Interest cost	1,073		1,259		64		72
Expected return on plan assets	(2,739)		(2,450)		—		—
Amortization of net actuarial loss	952		882		35		19
Net periodic benefit (income) cost	$	(289)	$	41	$	206	$	173