Pension And Other Postretirement Benefit Plans (Tables)

3 Months Ended

Jun. 30, 2020

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)	2020			2019			2020			2019
Service cost	$	1,541		$	1,589		$	48		$	53
Interest cost	2,454			2,737			287			333
Expected return on plan assets	(3,677		)	(4,216		)	(24		)	(27		)
Net amortization and deferral	1,121			698			(143		)	(152		)
Net periodic benefit cost	$	1,439		$	808		$	168		$	207