Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash Flows From Operating Activities:
Net income	$ 159.3	$ 145.7
Adjustments to reconcile cash provided by operating activities:
Provision for credit losses	40.0	14.6
Depreciation	3.2	2.9
Amortization	4.4	4.1
Loss on retirement of property and equipment	0.0	0.2
Provision for deferred income taxes	16.5	15.2
Stock-based compensation	3.8	6.7
Change in operating assets and liabilities:
Increase in accounts payable and accrued liabilities	2.6	11.2
Increase in income taxes receivable	0.0	(9.3)
Decrease in income taxes payable	0.0	(2.9)
Decrease (increase) in other assets	(1.3)	1.1
Net cash provided by operating activities	228.5	189.5
Cash Flows From Investing Activities:
Increase in restricted cash and cash equivalents	(66.3)	(19.9)
Purchases of restricted securities available for sale	(18.7)	(20.1)
Proceeds from sale of restricted securities available for sale	19.0	18.6
Maturities of restricted securities available for sale	2.1	2.4
Principal collected on Loans receivable	1,003.4	886.6
Advances to Dealers	(1,000.7)	(943.6)
Purchases of Consumer Loans	(370.8)	(174.2)
Accelerated payments of Dealer Holdback	29.7	26.6
Payments of Dealer Holdback	(75.8)	(78.6)
Purchases of property and equipment	(2.9)	(2.2)
Net cash used in investing activities	(540.4)	(357.6)
Cash Flows From Financing Activities:
Borrowings under revolving secured line of credit	1,036.1	1,123.1
Repayments under revolving secured line of credit	(1,093.8)	(1,217.8)
Proceeds from secured financing	1,397.3	571.4
Repayments of secured financing	(868.5)	(559.4)
Proceeds from issuance of senior notes	0.0	248.2
Payments of debt issuance costs	(5.5)	(8.1)
Repurchase of common stock	(40.8)	(1.1)
Tax benefits from stock-based compensation plans	27.2	0.3
Proceeds from (Payments for) Other Financing Activities	11.9	6.4
Net cash provided by financing activities	463.9	163.0
Net increase (decrease) in cash and cash equivalents	152.0	(5.1)
Cash and cash equivalents, beginning of period	6.3	6.4
Cash and cash equivalents, end of period	158.3	1.3
Supplemental Disclosure of Cash Flow Information:
Cash paid during the period for interest	41.6	25.7
Cash paid during the period for income taxes	$ 47.8	$ 79.9