Long Term Debt - Schedule of carrying values and fair values of debt instruments (Details) - USD ($) $ in Millions		Jun. 30, 2024	Dec. 31, 2023
CNK [Member]
Debt Instrument [Line Items]
Fair value	[1]	$ 2,517.4	$ 2,460.3
CUSA [Member]
Debt Instrument [Line Items]
Fair value		$ 1,788.6	$ 1,903.8

[1] The fair value of the 4.50% convertible senior notes was $728.8 and $556.5 as of June 30, 2024 and December 31, 2023, respectively.