Allowance for Finance Receivable Losses (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Changes in the allowance for finance receivable losses by finance receivable type
Balance at beginning of period	$ 180,136,000	$ 72,000,000
Provision for finance receivable losses	96,085,000	67,182,000
Charge-offs	(80,327,000)	(77,188,000)
Recoveries	13,851,000	14,449,000
Transfers to finance receivables held for sale		(1,301,000)
Amount of allowance for finance receivable losses associated with securitizations	24,900,000		14,700,000
Balance at end of period	209,745,000	75,142,000
Transfers to finance receivables held for sale which have a specific allowance		77,800,000
Net charge-offs on non-credit impaired finance receivables	34,300,000	53,800,000
Net charge-offs on credit impaired finance receivables	9,900,000	9,100,000
Consolidated VIEs
Changes in the allowance for finance receivable losses by finance receivable type
Balance at beginning of period			14,690,000
Balance at end of period	24,918,000		14,690,000
Consolidated VIEs | Out of period adjustment
Changes in the allowance for finance receivable losses by finance receivable type
Amount of allowance for finance receivable losses associated with securitizations			4,700,000
Personal Loans
Changes in the allowance for finance receivable losses by finance receivable type
Balance at beginning of period	66,580,000	39,522,000
Provision for finance receivable losses	25,021,000	21,229,000
Charge-offs	(42,769,000)	(29,916,000)
Recoveries	9,088,000	9,073,000
Transfers to finance receivables held for sale		(1,107,000)
Balance at end of period	57,920,000	38,801,000
Number of days past due before which a loan is charged off to the allowance for finance receivable losses	180 days
Minimum percentage of original loan amount to be received before charge off (as a percent)	0.05
Additional charge-offs	12,900,000
Retail Sales Finance
Changes in the allowance for finance receivable losses by finance receivable type
Balance at beginning of period	2,260,000	1,007,000
Provision for finance receivable losses	390,000	3,778,000
Charge-offs	(3,327,000)	(6,508,000)
Recoveries	2,327,000	3,030,000
Transfers to finance receivables held for sale		(194,000)
Balance at end of period	1,650,000	1,113,000
Real Estate Loans
Changes in the allowance for finance receivable losses by finance receivable type
Balance at beginning of period	111,296,000	31,471,000
Provision for finance receivable losses	70,674,000	42,175,000
Charge-offs	(34,231,000)	(40,764,000)
Recoveries	2,436,000	2,346,000
Balance at end of period	$ 150,175,000	$ 35,228,000