Basis of Presentation and Description of Business - Use of Proceeds from IPO (Details) - USD ($) $ in Millions				1 Months Ended	3 Months Ended	12 Months Ended
	Jul. 06, 2020	Feb. 08, 2019	Aug. 08, 2018	Feb. 07, 2019	Jun. 30, 2020	Dec. 31, 2021	Dec. 31, 2020		Dec. 31, 2019	[1]	Dec. 31, 2018	[1]	Dec. 20, 2021
Class of Stock [Line Items]
Gross proceeds	$ 2,381.0			$ 0.0		$ 0.0	$ 0.0	[1]			$ 3,176.8
Underwriter fees	89.1
IPO related expenses	42.8	$ 21.6	$ 21.6
Redemption of Series A Preferred Stock	1,067.9			0.0		0.0	1,067.9	[1]	$ 0.0
Make-whole payment on redemption of Series A Preferred Stock	205.2
Partial redemption of Notes and accrued interest				$ 0.0		0.0	$ 0.0	[1]	$ 625.1
Cash to balance sheet	331.7
10.250% Senior Unsecured Notes Due 2027
Class of Stock [Line Items]
Partial redemption of Notes and accrued interest	312.0
Payments for debt early redemption premiums reclassified to financing cash flows	30.8
10.250% Senior Unsecured Notes Due 2027 | Unsecured Debt
Class of Stock [Line Items]
Payments for debt early redemption premiums reclassified to financing cash flows					$ 30.8	29.5
Interest rate on debt instrument (as a percent)		10.25%					10.25%						10.25%
6.875% Senior Secured Notes Due 2026
Class of Stock [Line Items]
Partial redemption of Notes and accrued interest	282.2
Payments for debt early redemption premiums reclassified to financing cash flows	19.3
6.875% Senior Secured Notes Due 2026 | Unsecured Debt
Class of Stock [Line Items]
Interest rate on debt instrument (as a percent)		6.875%
6.875% Senior Secured Notes Due 2026 | Secured Debt
Class of Stock [Line Items]
Payments for debt early redemption premiums reclassified to financing cash flows						$ 19.3
Interest rate on debt instrument (as a percent)		6.875%				6.875%	6.875%						6.875%
Star Parent, L.P. | Affiliated Entity
Class of Stock [Line Items]
IPO related expenses	30.0
THL Managers | Affiliated Entity
Class of Stock [Line Items]
IPO related expenses	2.5
Bilcar | Board of Directors Chairman
Class of Stock [Line Items]
IPO related expenses	2.5
CC Star Holdings, LP | Director
Class of Stock [Line Items]
IPO related expenses	$ 2.5

[1] See Note 1 Basis of Presentation and Description of Business for further detail regarding the elimination of the International lag reporting