Basis and Summary of Significant Accounting Policies - Credit Quality Indicators (Details) |
Mar. 31, 2017 |
Dec. 31, 2016 |
|---|---|---|
| FICO Score, 600 or Less | ||
| Financing Receivable, Recorded Investment [Line Items] | ||
| Loans Receivable (net of allowances and unamortized fees of $14,646 in 2017 and $13,830 in 2016) | 1.80% | 1.80% |
| FICO Score, Between 600 and 700 | ||
| Financing Receivable, Recorded Investment [Line Items] | ||
| Loans Receivable (net of allowances and unamortized fees of $14,646 in 2017 and $13,830 in 2016) | 77.40% | 78.10% |
| FICO Score, 700 or Greater | ||
| Financing Receivable, Recorded Investment [Line Items] | ||
| Loans Receivable (net of allowances and unamortized fees of $14,646 in 2017 and $13,830 in 2016) | 20.80% | 20.10% |