Segment Data - Schedule of Adjusted EBITDA (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting [Abstract]
Net income (loss)	$ 131.3	$ (35.4)	$ 196.4
Depreciation and amortization	122.2	145.6	146.9
Interest expense, net of interest income	229.9	281.1	193.1
Provision for income taxes	44.5	5.4	141.6
Unrealized loss on investments, net	0.8	27.8	84.2
Loss on dispositions	18.4	1.8	0.0
Integration and other costs related to merger	4.9	11.2	14.0
Pre-IPO stock-based compensation	0.0	0.0	3.1
Acquisition related costs and efficiency initiatives	0.0	14.2	93.8
Cost savings initiatives	28.9	55.6	0.0
CEO transition costs	1.9	8.3	0.0
Servicing liability fees and amortization	(1.7)	11.7	7.9
Legal and compliance matters	0.0	23.0	0.0
Gain from insurance proceeds, net of legal fees	(16.5)	1.1	0.0
Other	17.3	18.7	17.8
Adjusted EBITDA	$ 581.9	$ 570.1	$ 898.8
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal, Statement of Income or Comprehensive Income [Extensible Enumeration]	Restructuring, impairment and related charges	Restructuring, impairment and related charges	Restructuring, impairment and related charges