Pension and Postretirement Benefit Plans

9 Months Ended

Sep. 30, 2020

Retirement Benefits [Abstract]

Pension and Postretirement Benefit Plans

Pension and Postretirement Benefit Plans

The following table sets forth information regarding the Company’s share of pension and postretirement benefit plans’

components of net periodic cost for the three and nine months ended September 30, 2020 and 2019:

($ millions)	Pension				Postretirement				Pension				Postretirement
	Three months ended September 30								Nine months ended September 30
	2020		2019		2020		2019		2020		2019		2020		2019
Service cost	$	1.2	$	0.8	$	—	$	—	$	3.6	$	2.8	$	—	$	—
Interest cost	2.4		2.9		0.2		0.2		7.2		8.6		0.4		0.5
Expected return on plan assets	(4.4)		(4.2)		—		—		(13.1)		(12.5)		—		—
Amortization of:
Negative prior service cost	—		—		(1.4)		(1.4)		—		—		(4.1)		(4.1)
Net actuarial loss	2.3		1.5		0.1		0.1		6.9		4.5		0.2		0.2
Net periodic cost (benefit)	$	1.5	$	1.0	$	(1.1)	$	(1.1)	$	4.6	$	3.4	$	(3.5)	$	(3.4)

The Company contributed $15.0 million to its pension plan for the nine months ended September 30, 2020.