Other income, net - Schedule of Components of Other Income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Interest income and other:
Interest and dividends			$ 7.4	$ 7.8
Securities transactions, net			0.1	0.2
Total			7.5	8.0
Currency transactions, net			(5.9)	5.0
Infrastructure reimbursement			16.8	17.5
Gain on building sale			5.8
Other, net			1.4	1.4
Total	$ 21.5	$ 31.1	25.6	$ 31.9
Proceeds from building sale			$ 6.8

Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

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