Consolidated Statements Of Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenues [Abstract]
Finance Charges Revenue	$ 1,755.4	$ 1,686.3	$ 1,742.6
Premiums earned	79.6	62.7	60.3
Other Income	66.9	83.4	53.1
Total revenue	1,901.9	1,832.4	1,856.0
Costs and expenses [Abstract]
Salaries and wages	280.2	262.0	218.1
General and administrative	87.2	88.7	100.3
Sales and marketing	91.7	75.6	65.3
Operating Expenses	459.1	426.3	383.7
Provision for credit losses	736.2	481.4	8.4
Interest	266.5	166.6	164.2
Provision for claims	70.7	46.4	38.8
Loss on extinguishment of debt	1.8	0.0	0.0
Total costs and expenses	1,534.3	1,120.7	595.1
Income before provision for income taxes	367.6	711.7	1,260.9
Provision for income taxes	81.5	175.9	302.6
Net income	$ 286.1	$ 535.8	$ 958.3
Net income per share [Abstract]
Basic	$ 22.09	$ 39.50	$ 59.57
Diluted	$ 21.99	$ 39.32	$ 59.52
Weighted average Shares Outstanding [Abstract]
Basic	12,953,424	13,563,885	16,085,823
Diluted	13,010,735	13,625,081	16,100,552