Goodwill and Intangible Assets (Changes to Intangible Assets) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Finite-Lived and Indefinite-Lived Intangible Assets [Roll Forward]
Balance at beginning of period, net of accumulated amortization	$ 308.9	$ 344.9
Amortization expense	(8.9)	(35.9)
Currency translation and other	(3.0)	(0.1)
Balance at end of period, net of accumulated amortization	$ 297.0	$ 308.9