Income Taxes - Schedule of Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	4 Months Ended	8 Months Ended	12 Months Ended
	Dec. 31, 2021	Sep. 07, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Uncertainties [Abstract]
Balance, beginning of year	$ 19.2	$ 19.2	$ 21.9	$ 22.0
Change in tax positions for the current year	0.1	0.0		0.2
Change in tax positions for the current year			(2.2)
Change in tax positions for prior years	0.0	0.0	(0.5)	(0.3)
Balance, end of year	$ 19.3	$ 19.2	$ 19.2	$ 21.9