Components of Net Periodic Benefit Cost

3 Months Ended

Mar. 31, 2019

Components of net periodic benefit cost [Abstract]

Components of Net Periodic Benefit Cost

Components of Net Periodic Benefit Cost

	Pension Benefits
	Three months ended March 31,
	2019			2018
Service cost	$	1.1		$	1.1
Interest cost	3.3			3.1
Expected return on plan assets	(4.9		)	(5.3		)
Amortization of prior service costs	0.0			0.0
Amortization of net loss	1.1			1.5
Net periodic benefit cost	$	0.6		$	0.4

	Other Postretirement Benefits ("OPEB")
	Three months ended March 31,
	2019			2018
Service cost	$	0.0		$	0.1
Interest cost	1.0			1.1
Amortization of prior service cost	(1.3		)	(1.8		)
Amortization of net loss	0.8			1.1
Net periodic benefit cost	$	0.5		$	0.5