Other (expense), net (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Intercompany Foreign Currency Balance [Line Items]
Postretirement expense	$ (12.1)	$ (10.2)	$ (158.3)	$ (203.1)
Foreign exchange (losses) gains	2.3	(3.2)	(12.6)	0.5
Other, net	0.4	(3.3)	19.4	(11.0)
Total other (expense), net	(9.4)	(16.7)	(151.5)	(213.6)
Foreign exchange gains (losses)	2.3	(3.2)	(12.6)	0.5
Net gain related to favorable judgement			14.9
Liquidation of Foreign Subsidiaries
Intercompany Foreign Currency Balance [Line Items]
Foreign exchange (losses) gains	(1.2)	(0.1)	(1.7)	3.4
Foreign exchange gains (losses)	$ (1.2)	$ (0.1)	(1.7)	3.4
Pension Plans
Intercompany Foreign Currency Balance [Line Items]
Settlement losses to defined benefit pension plans			$ 132.3	$ 183.2

Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

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