Debt - Schedule of Debt (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Debt	$ 2,525.2	$ 2,537.5
Senior bank debt
Debt Instrument [Line Items]
Debt	299.9	349.9
Senior notes
Debt Instrument [Line Items]
Debt	697.4	1,096.9
Junior subordinated notes
Debt Instrument [Line Items]
Debt	1,188.9	751.8
Junior convertible securities
Debt Instrument [Line Items]
Debt	$ 339.0	$ 338.9