Retirement benefits (Tables)

9 Months Ended

Sep. 30, 2024

Retirement Benefits [Abstract]

Schedule of Net Benefit Costs

The components of net periodic pension cost (credit) for our pension plans were as follows:

	U.S. Plans			Non-U.S. Plans		Total
(In millions)	2024		2023	2024	2023	2024	2023
Three months ended September 30,
Service cost	$	—	—	2.1	1.9	2.1	1.9
Interest cost on projected benefit obligation	7.7		8.1	4.4	4.6	12.1	12.7
Return on assets – expected	(11.6)		(11.8)	(2.9)	(2.8)	(14.5)	(14.6)
Amortization of losses	1.2		0.3	0.6	0.5	1.8	0.8
Amortization of prior service credit	—		—	0.1	0.1	0.1	0.1
Settlement loss	—		—	0.6	0.1	0.6	0.1
Net periodic pension cost (credit)	$	(2.7)	(3.4)	4.9	4.4	2.2	1.0
Nine months ended September 30,
Service cost	$	—	—	6.5	5.6	6.5	5.6
Interest cost on projected benefit obligation	23.1		24.3	13.3	13.5	36.4	37.8
Return on assets – expected	(34.8)		(35.4)	(8.6)	(8.3)	(43.4)	(43.7)
Amortization of losses	3.9		1.2	1.9	1.3	5.8	2.5
Amortization of prior service cost	—		—	0.1	0.1	0.1	0.1
Settlement loss	—		—	0.9	0.4	0.9	0.4
Net periodic pension cost (credit)	$	(7.8)	(9.9)	14.1	12.6	6.3	2.7

Schedule of Costs of Retirement Plans

The components of net periodic postretirement cost (credit) related to retirement benefits other than pensions were as follows:

	UMWA Plans			Black Lung and Other Plans		Total
(In millions)	2024		2023	2024	2023	2024	2023
Three months ended September 30,
Interest cost on accumulated postretirement benefit obligations	$	2.2	2.7	1.1	1.4	3.3	4.1
Return on assets – expected	(2.6)		(2.6)	—	—	(2.6)	(2.6)
Amortization of losses	0.1		1.1	1.2	1.3	1.3	2.4
Amortization of prior service cost (credit)	(2.4)		(2.7)	(0.1)	(0.1)	(2.5)	(2.8)
Net periodic postretirement cost (credit)	$	(2.7)	(1.5)	2.2	2.6	(0.5)	1.1
Nine months ended September 30,
Service cost	$	—	—	0.1	0.2	0.1	0.2
Interest cost on accumulated postretirement benefit obligations	7.4		8.4	3.5	4.0	10.9	12.4
Return on assets – expected	(7.7)		(7.8)	—	—	(7.7)	(7.8)
Amortization of losses	1.5		4.0	3.3	3.6	4.8	7.6
Amortization of prior service cost (credit)	(6.8)		(8.2)	—	(0.1)	(6.8)	(8.3)
Net periodic postretirement cost (credit)	$	(5.6)	(3.6)	6.9	7.7	1.3	4.1