Supplemental Financial Data - Narrative (Details) - USD ($) $ in Millions		1 Months Ended	12 Months Ended
	Jun. 30, 2021	Feb. 07, 2019	Dec. 31, 2021	Dec. 31, 2020		Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Capital expenditures		$ 0.2	$ 9.7	$ 7.8	[1]	$ 12.4	[1]
Depreciation		1.1	11.9	9.5		8.4
Asset impairment charges			0.2	4.4
Computer software amortization expense		$ 6.8	113.3	71.4		$ 50.6
Amortization			$ 490.7	$ 456.9
Office Building In Jacksonville, FL
Property, Plant and Equipment [Line Items]
Capital expenditures	$ 76.6
Asset acquisition, transaction cost	$ 0.1

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