Postretirement Benefits (Tables)

6 Months Ended

Jun. 30, 2021

Retirement Benefits [Abstract]

Schedule of Cost of Pension Plans

The cost of our pension plans are as follows:

	Three months ended June 30,				Six months ended June 30,
(in thousands)	2021		2020		2021		2020
Service cost for benefits earned	$	13,260	$	10,874	$	26,520	$	21,747
Interest cost on benefits obligation	9,206		9,394		18,412		18,789
Expected return on plan assets	(12,568)		(12,353)		(25,137)		(24,706)
Prior service cost amortization	357		335		714		671
Net actuarial loss amortization	4,026		3,031		8,053		6,062
Pension plan cost (1)	$	14,281	$	11,281	$	28,562	$	22,563

(1)The components of pension plan costs other than the service cost component are included in the line item "Other expense" in the Statements of Operations after reimbursements from the Exchange and its subsidiaries.