Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance as of January 1	$ 18.7	$ 18.4	$ 18.3
Additions for current year and prior year	0.6	0.3	0.1
Balance as of December 31	$ 19.3	$ 18.7	$ 18.4