Finance Receivables Credit Quality (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013 Rate	Dec. 31, 2012 Rate
Financing Receivable, Recorded Investment [Line Items]
Percent FICO Scores Less Than 540	28.40%	27.40%
Percent FICO Scores 540 to 599	46.10%	45.60%
Percent FICO Scores 600 to 659	21.90%	22.90%
Percent FICO Scores Greater Than 660	3.60%	4.10%
Notes, Loans and Financing Receivable, Net	$ 11,502,472	$ 10,998,274
Total Percent FICO	100.00%	100.00%
Commercial Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Gross	882,736	559,999
Notes, Loans and Financing Receivable, Net	871,867	553,896
Commercial Loan [Member] | Group 1 [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Gross	120,728	98,417
Commercial Loan [Member] | Group 2 [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Gross	447,155	278,403
Commercial Loan [Member] | Group 3 [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Gross	288,197	171,008
Commercial Loan [Member] | Group 4 [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Gross	22,480	12,171
Commercial Loan [Member] | Group 5 [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Gross	4,176
Consumer Credit Score [Member]
Financing Receivable, Recorded Investment [Line Items]
FICO Scores Less Than 540	3,177,979	3,010,927
FICO Scores 600 to 659	2,455,437	2,513,153
FICO Scores 540 to 599	5,164,094	5,013,812
Notes, Loans and Financing Receivable, Net	11,191,734	10,992,777
FICO Scores Greater Than 660	$ 394,224	$ 454,885