| **LOANS AND ALLOWANCE FOR CREDIT LOSSES (As Restated) (Retail Installment Contracts and Auto Loans) (Details) - USD ($) $ in Thousands**                                                                                                                                                                                                                                                                                                                                                                    | Sep. 30, 2015 | Dec. 31, 2014 |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |               |          |   |
| Total loans held for investment                                                                                                                                                                                                                                                                                                                                                                                                                                                                             | [1],[2]       | $ 78,583,198  | $ 75,995,467 |
| RICs - Purchased | Consumer | Consumer loans not secured by real estate                                                                                                                                                                                                                                                                                                                                                                                                                                     |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |               |          |   |
| UPB                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |               | 7,577,731     | 13,366,188 |
| UPB - FVO                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |               | 195,909       | 716,923 |
| Total UPB                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |               | 7,773,640     | 14,083,111 |
| Purchase Marks                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |               | (885,117)     | (1,633,585) |
| Total loans held for investment                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |               | 6,888,523     | 12,449,526 |
| Purchase Marks, FVO                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |               | 42,300        | 130,200 |
| RICs - Originated | Consumer | Consumer loans not secured by real estate                                                                                                                                                                                                                                                                                                                                                                                                                                    |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |               |          |   |
| Total UPB                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |               | 18,110,589    | 10,273,931 |
| Total loans held for investment                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |               | 17,554,637    | 9,906,562 |
| Net discount                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |               | (555,952)     | (367,369) |
| Auto loan | Consumer | Consumer loans not secured by real estate                                                                                                                                                                                                                                                                                                                                                                                                                                            |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |               |          |   |
| Total loans held for investment                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |               | 19,306        | 28,941 |
| Total RICs originated post-change in control | Consumer | Consumer loans not secured by real estate                                                                                                                                                                                                                                                                                                                                                                                                         |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |               |          |   |
| Total loans held for investment                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |               | 17,573,943    | 9,935,503 |
| Retail installment contracts and auto loans | Consumer | Consumer loans not secured by real estate                                                                                                                                                                                                                                                                                                                                                                                                          |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |               |          |   |
| Total loans held for investment                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |               | $ 24,462,466  | $ 22,385,029 |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| [1]Loans held for investment includes $374.2 million and $845.9 million of loans recorded at fair value at September 30, 2015 and December 31, 2014, respectively.[2]The Company has interests in certain securitization trusts ("Trusts") that are considered variable interest entities ("VIEs") for accounting purposes. The Company consolidates VIEs where it is deemed the primary beneficiary. See Note 7 to these Condensed Consolidated Financial Statements for additional information. |

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