Postretirement Benefits (Tables)

3 Months Ended

Mar. 31, 2021

Retirement Benefits [Abstract]

Schedule of Cost of Pension Plans

The cost of our pension plans are as follows:

	Three months ended March 31,
(in thousands)	2021		2020
Service cost for benefits earned	$	13,260	$	10,873
Interest cost on benefits obligation	9,206		9,395
Expected return on plan assets	(12,569)		(12,353)
Prior service cost amortization	357		336
Net actuarial loss amortization	4,027		3,031
Pension plan cost (1)	$	14,281	$	11,282

(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.