Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash Flows From Operating Activities:
Net income	$ 214.3	$ 202.1
Adjustments to reconcile cash provided by operating activities:
Provision for credit losses	23.3	21.3
Depreciation	2.3	2.4
Amortization	4.3	4.1
Provision for deferred income taxes	11.0	12.9
Stock-based compensation	9.1	1.1
Other	0.1	(0.1)
Change in operating assets and liabilities:
Increase in accounts payable and accrued liabilities	43.1	24.0
Decrease in income taxes receivable	56.3	48.7
Decrease in other assets	12.3	8.7
Net cash provided by operating activities	376.1	325.2
Payments to Acquire Debt Securities, Available-for-sale	11.4	11.8
Cash Flows From Investing Activities:
Proceeds from sale of restricted securities available for sale	5.4	5.2
Maturities of restricted securities available for sale	3.4	3.5
Principal collected on Loans receivable	961.9	973.0
Advances to Dealers	(633.8)	(647.1)
Purchases of Consumer Loans	(289.7)	(385.2)
Accelerated payments of Dealer Holdback	(9.4)	(10.4)
Payments of Dealer Holdback	(43.2)	(39.0)
Purchases of property and equipment	(1.7)	(0.8)
Net cash used in investing activities	(18.5)	(112.6)
Cash Flows From Financing Activities:
Borrowings under revolving secured line of credit	697.8	807.6
Repayments under revolving secured line of credit	(595.7)	(903.5)
Proceeds from secured financing	211.7	728.8
Repayments of secured financing	(193.8)	(521.3)
Payments of debt issuance costs	(0.8)	(7.6)
Repurchase of common stock	(423.0)	(135.2)
Proceeds from Issuance of Common Stock	5.9	0.0
Other	4.8	6.6
Net cash used in financing activities	(293.1)	(24.6)
Net increase in cash and cash equivalents and restricted cash and cash equivalents	64.5	188.0
Cash and cash equivalents and restricted cash and cash equivalents beginning of period	434.2	396.2
Cash and cash equivalents and restricted cash and cash equivalents end of period	498.7	584.2
Supplemental Disclosure of Cash Flow Information:
Cash paid during the period for interest	33.6	41.5
Cash paid during the period for income taxes, net of refunds	$ 0.6	$ 0.0