Finance Receivables Finance Receivables, net (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Dec. 31, 2010	Sep. 30, 2010	Dec. 31, 2012	Dec. 31, 2011	Jun. 30, 2010	Jun. 30, 2009
Finance Receivables, net [Line Items]
Financing Receivable, Net			$ 10,998,274	$ 9,162,492
Commercial Loan [Member]
Finance Receivables, net [Line Items]
Financing Receivable, Gross			559,999
Allowance for Notes, Loans and Financing Receivable			(6,103)
Financing Receivable, Net			553,896
Finance Receivables Purchased			1,227,287
Principal Collection and Recoveries on Receivables			(667,288)
Consumer Loans Auto Financing Receivable [Member]
Finance Receivables, net [Line Items]
Pre-Acquisition Finance Receivables Outstanding Balance			2,161,863	4,366,075
Pre-Acquisition Finance Receivables, Carrying Value	7,299,963	8,230,743	1,958,204	4,027,361	8,733,518	10,927,969
Post-Acquisition Finance Receivables, Carrying Value	923,713		8,830,914	5,313,899
Financing Receivable, Gross	8,223,676	8,675,575	10,789,118	9,341,260	8,733,518
Allowance for Notes, Loans and Financing Receivable			(344,740)	(178,768)
Financing Receivable, Net			10,444,378	9,162,492
Finance Receivables Purchased	934,812	959,004	5,578,839	5,084,800	2,137,620
Principal Collection and Recoveries on Receivables	$ (763,883)	$ (799,427)	$ (3,657,008)	$ (3,418,088)	$ (3,082,773)