EMPLOYEE BENEFITS

6 Months Ended

Jun. 30, 2021

Retirement Benefits [Abstract]

EMPLOYEE BENEFITS

EMPLOYEE BENEFITS

The following tables show the components of net periodic benefit cost (credit) for our benefit plans.

	Pension Benefits
	Three Months Ended June 30				Six Months Ended June 30
(in millions)	2021		2020		2021		2020
Service cost	$	3.9	$	2.9	$	7.2	$	6.2
Interest cost	7.7		9.4		15.5		18.9
Expected return on plan assets	(17.4)		(17.3)		(35.1)		(34.7)
Amortization of prior service credit	(0.1)		—		(0.1)		—
Amortization of net actuarial loss	11.0		9.8		21.0		18.9
Net periodic benefit cost	$	5.1	$	4.8	$	8.5	$	9.3

	OPEB Benefits
	Three Months Ended June 30				Six Months Ended June 30
(in millions)	2021		2020		2021		2020
Service cost	$	0.9	$	1.0	$	2.1	$	2.1
Interest cost	1.4		1.7		2.7		3.4
Expected return on plan assets	(4.2)		(3.9)		(8.4)		(7.8)
Amortization of prior service credit	(0.3)		(0.2)		(0.6)		(0.3)
Amortization of net actuarial gain	(2.8)		(2.9)		(5.5)		(5.3)
Net periodic benefit credit	$	(5.0)	$	(4.3)	$	(9.7)	$	(7.9)

During the six months ended June 30, 2021, we made contributions and payments of $2.6 million related to our pension plans and an insignificant amount related to our OPEB plans. We expect to make contributions and payments of $1.0 million related to our pension plans and $0.1 million related to our OPEB plans during the remainder of 2021, dependent upon various factors affecting us, including our liquidity position and possible tax law changes.