Retirement Benefits

9 Months Ended

Sep. 30, 2020

Retirement Benefits [Abstract]

Retirement Benefits

Retirement Benefits

The following table presents the components of retirement benefits expense (income): 

	Pension Benefits				Postretirement Medical and Life Insurance Benefits
	Three months ended September 30,
	2020		2019		2020		2019
	(In millions)
Interest cost on benefit obligation	$	10.7	$	13.2	$	0.2	$	0.3
Expected return on assets	(15.2)		(16.2)		—		—
Amortization of prior service costs (credits)	—		—		—		(0.1)
Amortization of net losses (gains)	14.3		10.2		(0.9)		(0.9)
Retirement benefits expense (income)	$	9.8	$	7.2	$	(0.7)	$	(0.7)

	Pension Benefits				Postretirement Medical and Life Insurance Benefits
	Nine months ended September 30,
	2020		2019		2020		2019
	(In millions)
Interest cost on benefit obligation	$	31.9	$	39.5	$	0.6	$	0.9
Expected return on assets	(45.4)		(48.6)		—		—
Amortization of prior service costs (credits)	0.1		0.1		—		(0.2)
Amortization of net losses (gains)	43.0		30.6		(2.8)		(2.8)
Retirement benefits expense (income)	$	29.6	$	21.6	$	(2.2)	$	(2.1)