Income Taxes - Components of Income Tax Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022		Dec. 31, 2021
Income Tax Disclosure [Abstract]
Current	$ 6.5	$ (0.7)		$ 27.7
Deferred	1.8	(2.6)		12.0
Total income tax expense (benefit)	$ 8.3	$ (3.3)	[1]	$ 39.7	[1]

[1] Recast for the adoption of ASU 2018-12. See Note 1 of the Consolidated Financial Statements