Retirement Benefits (Tables)

3 Months Ended

Mar. 31, 2023

Retirement Benefits [Abstract]

Schedule of Components of Retirement Benefits (Income) Expense

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

	Pension Benefits				Postretirement Medical and Life Insurance Benefits
	Three months ended March 31,
	2023		2022		2023		2022
	(In millions)
Interest cost on benefit obligation	$	12.5	$	8.9	$	0.2	$	0.1
Expected return on assets	(14.4)		(15.7)		—		—
Amortization of net losses (gains)	—		7.7		(0.7)		(0.7)
Retirement benefits (income) expense	$	(1.9)	$	0.9	$	(0.5)	$	(0.6)