| **FAIR VALUE (As Restated) (Fair Value Measurements, Non-recurring) (Details) - USD ($) $ in Thousands**                                      | 3 Months Ended | 6 Months Ended |           |
|-----------------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|-----------|
||
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                                              |           |           |      |   |   |
| Impaired loans held for investment                                                                                                            | $ 494,700      |           | $ 494,700 |   | $ 845,900 |
| Total carrying value of the loans                                                                                                             | 4,095,981      |           | 4,095,981 |   | 2,519,217 |
| Nonrecurring [Member]                                                                                                                         |           |           |      |   |   |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                                              |           |           |      |   |   |
| Foreclosed assets                                                                                                                             | 13,345         |           | 13,345    |   | 45,599 |
| Vehicle inventory                                                                                                                             | 177,459        |           | 177,459   |   | 136,136 |
| Fair value adjustment                                                                                                                         | (2,147)        | $ (9,785)      | (3,288)   | $ (10,552) |   |
| Indefinite-lived intangibles                                                                                                                  |           |           |      |   | 21,500 |
| Nonrecurring [Member] | Impaired loans held for investment [Member]                                                                           |           |           |      |   |   |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                                              |           |           |      |   |   |
| Impaired loans held for investment                                                                                                            | 94,821         |           | 94,821    |   | 168,917 |
| Total carrying value of the loans                                                                                                             | 54,800         |           | 54,800    |   | 100,200 |
| Nonrecurring [Member] | Impaired loans held for investment [Member] | Provision for credit losses [Member]                                    |           |           |      |   |   |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                                              |           |           |      |   |   |
| Fair value adjustment                                                                                                                         | (1,731)        | (9,656)        | (2,261)   | (10,200) |   |
| Nonrecurring [Member] | Foreclosed assets [Member] | Other administrative expense [Member]                                                    |           |           |      |   |   |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                                              |           |           |      |   |   |
| Fair value adjustment                                                                                                                         | (416)          | $ (129)        | (1,027)   | $ (352) |   |
| Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]                                               |           |           |      |   |   |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                                              |           |           |      |   |   |
| Foreclosed assets                                                                                                                             | 0              |           | 0         |   | 0 |
| Vehicle inventory                                                                                                                             | 0              |           | 0         |   | 0 |
| Indefinite-lived intangibles                                                                                                                  |           |           |      |   | 0 |
| Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Impaired loans held for investment [Member] |           |           |      |   |   |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                                              |           |           |      |   |   |
| Impaired loans held for investment                                                                                                            | 3,333          |           | 3,333     |   | 0 |
| Nonrecurring [Member] | Significant Other Observable Inputs (Level 2) [Member]                                                                |           |           |      |   |   |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                                              |           |           |      |   |   |
| Foreclosed assets                                                                                                                             | 13,345         |           | 13,345    |   | 45,599 |
| Vehicle inventory                                                                                                                             | 177,459        |           | 177,459   |   | 136,136 |
| Indefinite-lived intangibles                                                                                                                  |           |           |      |   | 0 |
| Nonrecurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Impaired loans held for investment [Member]                  |           |           |      |   |   |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                                              |           |           |      |   |   |
| Impaired loans held for investment                                                                                                            | 91,274         |           | 91,274    |   | 101,218 |
| Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member]                                                                    |           |           |      |   |   |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                                              |           |           |      |   |   |
| Foreclosed assets                                                                                                                             | 0              |           | 0         |   | 0 |
| Vehicle inventory                                                                                                                             | 0              |           | 0         |   | 0 |
| Indefinite-lived intangibles                                                                                                                  |           |           |      |   | 21,500 |
| Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Impaired loans held for investment [Member]                      |           |           |      |   |   |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                                              |           |           |      |   |   |
| Impaired loans held for investment                                                                                                            | $ 214          |           | $ 214     |   | $ 67,699 |

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Foreclosed Assets Measured at Fair Value
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| - Definition
Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Fair value portion of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19190-110258
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Glossary Loan -URI http://asc.fasb.org/extlink&oid=6517073
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