Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Statement of Comprehensive Income [Abstract]
Net income	$ 764.9	$ 761.4	$ 235.0
Other comprehensive income (loss), net of income tax:
Foreign currency translation adjustments	(43.0)	24.6	(85.6)
Unrealized holding gains (losses) on financial investments	5.0	(2.8)	(0.8)
Post-retirement benefit obligations	0.3	(0.2)	(0.2)
Realized gains on available-for-sale financial investments	(1.3)	0.0	0.0
Comprehensive income	725.9	783.0	148.4
Comprehensive income allocated to participating securities	(3.9)	(3.9)	(0.9)
Comprehensive income allocated to common stockholders, net of income tax	$ 722.0	$ 779.1	$ 147.5