Employee Benefits (Tables)

9 Months Ended

Sep. 30, 2020

Retirement Benefits [Abstract]

Schedule of Net Benefit Costs

Components of net periodic benefit cost for both the Retirement Plans and PBOP for the three months ended September 30, 2020 and 2019, were as follows (in millions):

	Retirement Plans				PBOP
	For the Three Months Ended September 30,				For the Three Months Ended September 30,
	2020		2019		2020		2019
Service cost	$	0.7	$	0.7	$	—	$	—
Interest cost	0.7		0.9		0.3		0.4
Expected return on plan assets	(1.4)		(1.6)		(0.8)		(0.6)
Amortization of unrecognized net loss	0.8		0.4		—		—
Settlement charge	0.6		0.6		—		—
Net periodic benefit cost	$	1.4	$	1.0	$	(0.5)	$	(0.2)

Components of net periodic benefit cost for both the Retirement Plans and PBOP for the nine months ended September 30, 2020 and 2019, were as follows (in millions):

	Retirement Plans				PBOP
	For the Nine Months Ended September 30,				For the Nine Months Ended September 30,
	2020		2019		2020		2019
Service cost	$	2.1	$	2.3	$	—	$	—
Interest cost	2.2		3.1		0.9		1.1
Expected return on plan assets	(4.7)		(4.8)		(2.4)		(2.2)
Amortization of unrecognized net loss	1.6		1.6		—		—
Settlement charge	2.2		2.7		—		—
Net periodic benefit cost	$	3.4	$	4.9	$	(1.5)	$	(1.1)