| **VARIABLE INTEREST ENTITIES AND EQUITY METHOD INVESTMENTS (As Restated) (Tables)** | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
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| **Variable Interest Entity and Securitizations [Abstract]**                         |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| Schedule of Variable Interest Entities                                              | The assets of consolidated VIEs that are included in the Company's Condensed Consolidated Financial Statements, presented based upon the legal transfer of the underlying assets in order to reflect legal ownership, that can be used only to settle obligations of the consolidated VIE and the liabilities of these entities for which creditors (or beneficial interest holders) do not have recourse to our general credit were as follows:  December 31, 2015 December 31, 2014  (in thousands)     Assets    Restricted cash $1,842,877 $1,626,257RICs, net(1) 23,494,541 20,557,168Leased vehicles, net 6,497,310 4,848,593Various other assets 630,017 555,108   Total Assets 32,464,745 27,587,126Liabilities   Notes payable 30,628,837 27,892,669Various other liabilities 85,844 55,795   Total Liabilities $30,714,681 $27,948,464(1) Includes $1.5 billion and $18.7 million of RICs held for sale at December 31, 2015 and December 31, 2014, respectively.                                                                                                                                                                                                                                                                                                         |
| Summary of Cash Flows Received                                                      | Below is a summary of the cash flows received from the Trusts for the period indicated:       Year Ended December 31, 2015 Period from January 28, 2014 to December 31, 2014      (in thousands)Receivables securitized $18,516,641 $12,509,094     Net proceeds from new securitizations (1) 15,232,692 10,452,530Cash received for servicing fees (2) 700,156 585,117Cash received upon release from reserved and restricted cash accounts (2) — —Net distributions from Trusts (2) 1,960,418 1,717,839Total cash received from securitization trusts $17,893,266 $12,755,486(1)  Includes additional advances on existing securitizations.(2) These amounts are not reflected in the accompanying consolidated statements of cash flows because the cash flows are between the VIEs and other entities included in the consolidationA summary of the cash flows received from the off-balance Trusts for the periods indicated is as follows: Year Ended December 31, Period from January 28, 2014 to December 31,  2015 2014 (in thousands)Receivables securitized$1,557,099 $1,802,461    Net proceeds from new securitizations1,578,320 1,894,052Cash received for servicing fees23,848 17,000Total cash received from securitization trusts$1,602,168 $1,911,052 |
| Schedule of Equity Method Investments                                               | Investments in unconsolidated entities as of December 31, 2015 and 2014 include the following: OwnershipInterest December 31, 2015 December 31, 2014   (in thousands)Community reinvestment projects2.0 - 99.9% $33,103 $55,313Tax credit investmentsvarious 197,113 113,462Othervarious 36,353 59,216         Total  $266,569 $227,991                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |

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Schedule of Cash Flows Between Transferor and Transferee [Table Text Block]
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Tabular disclosure of equity method investments including, but not limited to, name of each investee or group of investments, percentage ownership, difference between recorded amount of an investment and the value of the underlying equity in the net assets, and summarized financial information.
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Tabular disclosure of the significant judgments and assumptions made in determining whether a variable interest (as defined) held by the entity requires the variable interest entity (VIE) (as defined) to be consolidated and (or) disclose information about its involvement with the VIE, individually or in aggregate (as applicable); the nature of restrictions, if any, on the consolidated VIE's assets and on the settlement of its liabilities reported by an entity in its statement of financial position, including the carrying amounts of such assets and liabilities; the nature of, and changes in, the risks associated with involvement in the VIE; how involvement with the VIE affects the entity's financial position, financial performance, and cash flows; the lack of recourse if creditors (or beneficial interest holders) of the consolidated VIE have no recourse to the general credit of the primary beneficiary (if applicable); the terms of arrangements, giving consideration to both explicit arrangements and implicit variable interests, if any, that could require the entity to provide financial support to the VIE, including events or circumstances that could expose the entity to a loss; the methodology used by the entity for determining whether or not it is the primary beneficiary of the variable interest entity; the significant factors considered and judgments made in determining that the power to direct the activities of a VIE that most significantly impact the VIE's economic performance are shared (as defined); the carrying amounts and classification of assets and liabilities of the VIE included in the statement of financial position; the entity's maximum exposure to loss, if any, as a result of its involvement with the VIE, including how the maximum exposure is determined and significant sources of the entity's exposure to the VIE; a comparison of the carrying amounts of the assets and liabilities and the entity's maximum exposure to loss; information about any liquidity arrangements, guarantees, and (or) other commitments by third parties that may affect the fair value or risk of the entity's variable interest in the VIE; whether or not the entity has provided financial support or other support (explicitly or implicitly) to the VIE that it was not previously contractually required to provide or whether the entity intends to provide that support, including the type and amount of the support and the primary reasons for providing the support; and supplemental information the entity determines necessary to provide.
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