Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Cash Flows From Operating Activities:
Net income	$ 50,338	$ 43,191
Adjustments to reconcile cash provided by operating activities:
Provision for credit losses	5,247	8,916
Depreciation	1,237	1,025
Amortization	1,605	1,463
Loss on retirement of property and equipment	0	4
Provision for deferred income taxes	5,934	(5,377)
Stock-based compensation	822	591
Change in operating assets and liabilities:
Increase in accounts payable and accrued liabilities	11,467	21,959
Decrease in income taxes receivable	100	11,294
Increase in income taxes payable	11,530	10,542
Decrease (increase) in other assets	990	(7,537)
Net cash provided by operating activities	89,270	86,071
Cash Flows From Investing Activities:
Increase in restricted cash and cash equivalents	(55,390)	(14,834)
Purchases of restricted securities available for sale	0	(303)
Maturities of restricted securities available for sale	0	305
Principal collected on Loans receivable	310,795	253,592
Advances to Dealer-Partners	(374,392)	(336,408)
Purchases of Consumer Loans	(34,789)	(32,726)
Accelerated payments of Dealer Holdback	(12,914)	(12,045)
Payments of Dealer Holdback	(33,205)	(15,574)
Net decrease (increase) in other loans	35	(230)
Purchases of property and equipment	(3,933)	(1,582)
Net cash used in investing activities	(203,793)	(159,805)
Cash Flows From Financing Activities:
Borrowings under revolving secured line of credit	607,500	489,000
Repayments under revolving secured line of credit	(477,800)	(492,900)
Proceeds from secured financing	492,350	150,000
Repayments of secured financing	(487,081)	(51,500)
Principal payments under mortgage note and capital lease obligations	(61)	(58)
Proceeds from sale of senior notes	0	106,000
Payments of debt issuance costs	(1,802)	(3,028)
Repurchase of common stock	(19,999)	(126,675)
Proceeds from stock options exercised	172	1,915
Tax benefits from stock-based compensation plans	1,278	1,773
Net cash provided by financing activities	114,557	74,527
Net increase in cash and cash equivalents	34	793
Cash and cash equivalents, beginning of period	4,657	3,792
Cash and cash equivalents, end of period	4,691	4,585
Supplemental Disclosure of Cash Flow Information:
Cash paid during the period for interest	13,413	10,867
Cash paid during the period for income taxes	$ 9,665	$ 6,306