Retirement benefits (Tables)

9 Months Ended

Sep. 30, 2023

Retirement Benefits [Abstract]

Schedule of Net Benefit Costs

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

	U.S. Plans			Non-U.S. Plans		Total
(In millions)	2023		2022	2023	2022	2023	2022
Three months ended September 30,
Service cost	$	—	—	1.9	2.0	1.9	2.0
Interest cost on projected benefit obligation	8.1		5.8	4.6	3.2	12.7	9.0
Return on assets – expected	(11.8)		(12.1)	(2.8)	(3.2)	(14.6)	(15.3)
Amortization of losses	0.3		5.9	0.5	0.5	0.8	6.4
Amortization of prior service credit	—		—	0.1	(0.1)	0.1	(0.1)
Settlement loss	—		—	0.1	0.1	0.1	0.1
Net periodic pension cost	$	(3.4)	(0.4)	4.4	2.5	1.0	2.1
Nine months ended September 30,
Service cost	$	—	—	5.6	6.1	5.6	6.1
Interest cost on projected benefit obligation	24.3		17.2	13.5	9.8	37.8	27.0
Return on assets – expected	(35.4)		(36.5)	(8.3)	(9.5)	(43.7)	(46.0)
Amortization of losses	1.2		18.0	1.3	1.5	2.5	19.5
Amortization of prior service cost	—		—	0.1	(0.1)	0.1	(0.1)
Settlement loss	—		—	0.4	0.6	0.4	0.6
Net periodic pension cost	$	(9.9)	(1.3)	12.6	8.4	2.7	7.1

Schedule of Costs of Retirement Plans

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

	UMWA Plans			Black Lung and Other Plans		Total
(In millions)	2023		2022	2023	2022	2023	2022
Three months ended September 30,
Interest cost on accumulated postretirement benefit obligations	$	2.7	2.5	1.4	0.9	4.1	3.4
Return on assets – expected	(2.6)		(3.3)	—	—	(2.6)	(3.3)
Amortization of losses	1.1		2.4	1.3	1.8	2.4	4.2
Amortization of prior service cost	(2.7)		(1.2)	(0.1)	(0.1)	(2.8)	(1.3)
Net periodic postretirement cost	$	(1.5)	0.4	2.6	2.6	1.1	3.0
Nine months ended September 30,
Service cost	$	—	—	0.2	0.1	0.2	0.1
Interest cost on accumulated postretirement benefit obligations	8.4		7.8	4.0	2.7	12.4	10.5
Return on assets – expected	(7.8)		(9.9)	—	—	(7.8)	(9.9)
Amortization of losses	4.0		7.7	3.6	5.5	7.6	13.2
Amortization of prior service cost	(8.2)		(3.5)	(0.1)	(0.2)	(8.3)	(3.7)
Net periodic postretirement cost	$	(3.6)	2.1	7.7	8.1	4.1	10.2