Loans Receivable (Schedule Of Consumer Loans Performance) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Jun. 30, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Dec. 31, 2010
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 2,047,481	$ 1,977,794	$ 1,752,891	$ 1,674,431	$ 1,582,905	$ 1,344,881
Allowance for credit losses	(170,763)	(161,905)	(154,318)	(149,028)	(144,819)	(126,868)
Loans receivable, net	1,876,718		1,598,573
Loan Pool Performance Meets Or Exceeds Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	768,590		704,428
Allowance for credit losses	0		0
Loans receivable, net	768,590		704,428
Loan Pool Performance Less Than Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	1,278,892		1,048,463
Allowance for credit losses	(170,763)		(154,318)
Loans receivable, net	1,108,129		894,145
Dealer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	1,807,701	1,736,578	1,506,539	1,426,866	1,331,973	1,082,039
Allowance for credit losses	(161,284)	(152,031)	(141,712)	(136,157)	(131,728)	(113,227)
Loans receivable, net	1,646,417		1,364,827
Dealer Loans [Member] | Loan Pool Performance Meets Or Exceeds Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	572,223		511,926
Allowance for credit losses	0		0
Loans receivable, net	572,223		511,926
Dealer Loans [Member] | Loan Pool Performance Less Than Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	1,235,479		994,613
Allowance for credit losses	(161,284)		(141,712)
Loans receivable, net	1,074,195		852,901
Purchased Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	239,780	241,216	246,352	247,565	250,932	262,842
Allowance for credit losses	(9,479)	(9,874)	(12,606)	(12,871)	(13,091)	(13,641)
Loans receivable, net	230,301		233,746
Purchased Loans [Member] | Loan Pool Performance Meets Or Exceeds Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	196,367		192,502
Allowance for credit losses	0		0
Loans receivable, net	196,367		192,502
Purchased Loans [Member] | Loan Pool Performance Less Than Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	43,413		53,850
Allowance for credit losses	(9,479)		(12,606)
Loans receivable, net	$ 33,934		$ 41,244