Pension And Other Postretirement Benefit Plans (Tables)

6 Months Ended

Sep. 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 September 30,				Three Months Ended September 30,
(in thousands of dollars)	2020		2019		2020		2019
Service cost	$	1,547	$	1,477	$	49	$	53
Interest cost	2,459		2,710		286		331
Expected return on plan assets	(3,679)		(4,190)		(24)		(29)
Net amortization and deferral	1,120		698		(142)		(153)
Net periodic benefit cost	$	1,447	$	695	$	169	$	202

	Pension Benefits				Other Postretirement Benefits
	Six Months Ended September 30,				Six Months Ended September 30,
(in thousands of dollars)	2020		2019		2020		2019
Service cost	$	3,088	$	3,066	$	97	$	106
Interest cost	4,913		5,447		573		664
Expected return on plan assets	(7,356)		(8,406)		(48)		(56)
Net amortization and deferral	2,241		1,396		(285)		(305)
Net periodic benefit cost	$	2,886	$	1,503	$	337	$	409