Retirement Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2023

Retirement Benefits [Abstract]

Summary of Net Periodic Benefit Cost

The following tables summarize the components of net periodic benefit cost (income):

	Three months ended June 30,
	2023						2022
(In thousands)	Pension		SERP		OPEB		Pension		SERP		OPEB
Service cost	$	—	$	—	$	7	$	—	$	—	$	9
Interest cost	2,211		47		263		1,380		17		213
Expected return on plan assets	(2,699)		—		—		(3,668)		—		—
Amortization of actuarial loss (gain)	1,216		2		(677)		423		6		(19)
Net periodic benefit cost (income)	$	728	$	49	$	(407)	$	(1,865)	$	23	$	203

	Six months ended June 30,
	2023						2022
(In thousands)	Pension		SERP		OPEB		Pension		SERP		OPEB
Service cost	$	—	$	—	$	14	$	—	$	—	$	15
Interest cost	4,422		114		643		2,757		32		357
Expected return on plan assets	(5,398)		—		—		(7,337)		—		—
Amortization of actuarial loss (gain)	2,432		3		(1,352)		845		13		(37)
Net periodic benefit cost (income)	$	1,456	$	117	$	(695)	$	(3,735)	$	45	$	335