| **LOANS AND ALLOWANCE FOR CREDIT LOSSES (As Restated) (Consumer Lending Asset Quality Indicators-Credit Score) (Details) - USD ($) $ in Thousands**                                                                                                                                                                                                                                                                                                                                                     | Mar. 31, 2015 | Dec. 31, 2014 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    | [1],[2]       | $ 78,438,960  | $ 75,995,467 |
| Retail installment contracts and auto loans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 24,341,530  | $ 22,430,453 |
| Percentage of total loans, Retail installment contracts and auto loans                                                                                                                                                                                                                                                                                                                                                                                                                                  |               | 100.00%       | 100.00% |
| Retail installment contracts and auto loans [Member] | FICO score less than 600 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 12,371,450  | $ 11,669,878 |
| Percentage of total loans, Retail installment contracts and auto loans                                                                                                                                                                                                                                                                                                                                                                                                                                  |               | 50.90%        | 52.00% |
| Retail installment contracts and auto loans [Member] | FICO score of 600 to 639 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 4,070,863   | $ 4,046,452 |
| Percentage of total loans, Retail installment contracts and auto loans                                                                                                                                                                                                                                                                                                                                                                                                                                  |               | 16.70%        | 18.00% |
| Retail installment contracts and auto loans [Member] | FICO score of 640 to 679 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 3,415,553   | $ 4,046,452 |
| Percentage of total loans, Retail installment contracts and auto loans                                                                                                                                                                                                                                                                                                                                                                                                                                  |               | 14.00%        | 18.00% |
| Retail installment contracts and auto loans [Member] | FICO score of 680 to 719 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 0           | $ 0 |
| Percentage of total loans, Retail installment contracts and auto loans                                                                                                                                                                                                                                                                                                                                                                                                                                  |               | 0.00%         | 0.00% |
| Retail installment contracts and auto loans [Member] | FICO score of 720 to 759 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 0           | $ 0 |
| Percentage of total loans, Retail installment contracts and auto loans                                                                                                                                                                                                                                                                                                                                                                                                                                  |               | 0.00%         | 0.00% |
| Retail installment contracts and auto loans [Member] | FICO score equal to or greater than 760 [Member]                                                                                                                                                                                                                                                                                                                                                                                                 |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 0           | $ 0 |
| Percentage of total loans, Retail installment contracts and auto loans                                                                                                                                                                                                                                                                                                                                                                                                                                  |               | 0.00%         | 0.00% |
| Retail installment contracts and auto loans [Member] | FICO score not refreshed [Member]                                                                                                                                                                                                                                                                                                                                                                                                                |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 4,483,664   | $ 2,667,671 |
| Percentage of total loans, Retail installment contracts and auto loans                                                                                                                                                                                                                                                                                                                                                                                                                                  |               | 18.40%        | 12.00% |
| Personal unsecured loans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 2,696,815   | $ 2,696,820 |
| Percentage of total loans, Personal unsecured loans balance                                                                                                                                                                                                                                                                                                                                                                                                                                             |               | 100.00%       | 100.00% |
| Personal unsecured loans [Member] | FICO score less than 600 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                   |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 472,501     | $ 491,984 |
| Percentage of total loans, Personal unsecured loans balance                                                                                                                                                                                                                                                                                                                                                                                                                                             |               | 17.50%        | 18.20% |
| Personal unsecured loans [Member] | FICO score of 600 to 639 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                   |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 439,314     | $ 446,995 |
| Percentage of total loans, Personal unsecured loans balance                                                                                                                                                                                                                                                                                                                                                                                                                                             |               | 16.30%        | 16.60% |
| Personal unsecured loans [Member] | FICO score of 640 to 679 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                   |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 1,189,155   | $ 1,163,203 |
| Percentage of total loans, Personal unsecured loans balance                                                                                                                                                                                                                                                                                                                                                                                                                                             |               | 44.10%        | 43.10% |
| Personal unsecured loans [Member] | FICO score of 680 to 719 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                   |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 64,417      | $ 64,610 |
| Percentage of total loans, Personal unsecured loans balance                                                                                                                                                                                                                                                                                                                                                                                                                                             |               | 2.40%         | 2.40% |
| Personal unsecured loans [Member] | FICO score of 720 to 759 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                   |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 72,614      | $ 72,235 |
| Percentage of total loans, Personal unsecured loans balance                                                                                                                                                                                                                                                                                                                                                                                                                                             |               | 2.70%         | 2.70% |
| Personal unsecured loans [Member] | FICO score equal to or greater than 760 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                    |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 76,368      | $ 78,234 |
| Percentage of total loans, Personal unsecured loans balance                                                                                                                                                                                                                                                                                                                                                                                                                                             |               | 2.80%         | 2.90% |
| Personal unsecured loans [Member] | FICO score not refreshed [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                   |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 382,446     | $ 379,559 |
| Percentage of total loans, Personal unsecured loans balance                                                                                                                                                                                                                                                                                                                                                                                                                                             |               | 14.20%        | 14.10% |
| Home equity loans and lines of credit [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                          |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 6,176,299   | $ 6,211,298 |
| Percentage of total loans, Home equity loans and lines                                                                                                                                                                                                                                                                                                                                                                                                                                                  |               | 100.00%       | 100.00% |
| Home equity loans and lines of credit [Member] | FICO score less than 600 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                      |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 304,669     | $ 286,694 |
| Percentage of total loans, Home equity loans and lines                                                                                                                                                                                                                                                                                                                                                                                                                                                  |               | 4.90%         | 4.50% |
| Home equity loans and lines of credit [Member] | FICO score of 600 to 639 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                      |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 283,304     | $ 278,594 |
| Percentage of total loans, Home equity loans and lines                                                                                                                                                                                                                                                                                                                                                                                                                                                  |               | 4.60%         | 4.50% |
| Home equity loans and lines of credit [Member] | FICO score of 640 to 679 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                      |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 509,672     | $ 514,502 |
| Percentage of total loans, Home equity loans and lines                                                                                                                                                                                                                                                                                                                                                                                                                                                  |               | 8.30%         | 8.30% |
| Home equity loans and lines of credit [Member] | FICO score of 680 to 719 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                      |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 856,525     | $ 867,323 |
| Percentage of total loans, Home equity loans and lines                                                                                                                                                                                                                                                                                                                                                                                                                                                  |               | 13.90%        | 14.00% |
| Home equity loans and lines of credit [Member] | FICO score of 720 to 759 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                      |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 1,193,212   | $ 1,181,245 |
| Percentage of total loans, Home equity loans and lines                                                                                                                                                                                                                                                                                                                                                                                                                                                  |               | 19.30%        | 19.00% |
| Home equity loans and lines of credit [Member] | FICO score equal to or greater than 760 [Member]                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 2,816,648   | $ 2,861,721 |
| Percentage of total loans, Home equity loans and lines                                                                                                                                                                                                                                                                                                                                                                                                                                                  |               | 45.60%        | 46.10% |
| Home equity loans and lines of credit [Member] | FICO score not refreshed [Member]                                                                                                                                                                                                                                                                                                                                                                                                                      |               |          |   |
| **Loans Receivable [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |               |          |   |
| Financing receivable                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |               | $ 212,269     | $ 221,219 |
| Percentage of total loans, Home equity loans and lines                                                                                                                                                                                                                                                                                                                                                                                                                                                  |               | 3.40%         | 3.60% |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| [1]Loans held for investment includes $676.1 million and $845.9 million of loans recorded at fair value at March 31, 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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| - Definition
Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.
+ References
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