Loan Loss Allowance and Credit Quality - Summary of Credit Risk Profile (Details)	Jun. 30, 2014	Dec. 31, 2013
FICO Band 540
Financing Receivable Recorded Investment [Line Items]
Retail Installment Contracts Held for Investment	26.70%	26.80%
Unsecured Consumer Loans	10.00%	6.30%
FICO Band 540-599
Financing Receivable Recorded Investment [Line Items]
Retail Installment Contracts Held for Investment	32.30%	31.80%
Unsecured Consumer Loans	21.30%	24.20%
FICO Band 600-659
Financing Receivable Recorded Investment [Line Items]
Retail Installment Contracts Held for Investment	26.50%	26.30%
Unsecured Consumer Loans	40.90%	39.40%
FICO Band 660
Financing Receivable Recorded Investment [Line Items]
Retail Installment Contracts Held for Investment	14.50%	15.10%
Unsecured Consumer Loans	27.80%	30.10%