Pension And Other Postretirement Benefit Plans (Tables)

3 Months Ended

Jun. 30, 2022

Retirement Benefits [Abstract]

Components of Company's Net Periodic Benefit Cost

The components of the Company’s net periodic benefit cost were as follows:

	Pension Benefits				Other Postretirement Benefits
	Three Months Ended June 30,				Three Months Ended June 30,
(in thousands of dollars)	2022		2021		2022		2021
Service cost	$	1,545	$	1,650	$	32	$	47
Interest cost	2,335		2,259		241		239
Expected return on plan assets	(3,324)		(3,385)		(19)		(22)
Net amortization and deferral	1,001		976		(172)		(115)
Net periodic benefit cost	$	1,557	$	1,500	$	82	$	149