| **LEASED VEHICLES, NET** | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
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| **Leases [Abstract]**    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| LEASED VEHICLES, NET     | LEASED VEHICLES, NETThe Company has operating leases which are included in the Company's Condensed Consolidated Balance Sheets as Leased vehicles, net. The leased vehicle portfolio consists primarily of leases originated under a ten-year private label financing agreement signed by the Company with Fiat Chrysler Automobiles US LLC ("FCA"), formerly Chrysler Group LLC, to be a preferred lender (the "Chrysler Agreement"). Under the Chrysler Agreement, the Company had the first right to review and approve all prime consumer vehicle lease applications originated under the Chrysler Capital program (“Chrysler Capital”), the trade name used in providing services under the Chrysler Capital Agreement. SC provides servicing on all leases originated under this agreement.Leased vehicles, net consisted of the following as of June 30, 2016 and December 31, 2015:  June 30, 2016 December 31, 2015  (in thousands)Leased vehicles $13,114,696 $11,297,752Origination fees and other costs 30,717 29,800Manufacturer subvention payments, net of accretion (1,209,870) (1,048,713)Leased vehicles, gross 11,935,543 10,278,839Less: accumulated depreciation (2,406,801) (1,901,004)Leased vehicles, net $9,528,742 $8,377,835NOTE 5. LEASED VEHICLES, NET (continued)For the three-month and six-month periods endedJune 30, 2016, the Company did not execute any bulk sales of leases originated under the Chrysler Capital. During the three-month and six-month periods endedJune 30, 2015, the Company executed a bulk sale of leases originated under the Chrysler Capital program with depreciated net capitalized costs of $755.6 million and $1.3 billion, respectively, and a net book value of $666.3 million and $1.2 billion, respectively, to a third party. The bulk sales agreement included certain provisions under which SC agreed to share in residual losses for lease terminations with losses over a specific percentage threshold. SC retained servicing on the leases sold. Due to the accelerated depreciation permitted for tax purposes, this sale generated large taxable gains that SC deferred through a qualified like-kind exchange program. An immaterial amount of taxable gain that did not qualify for deferral was recognized upon expiration of the reinvestment period.The following summarizes the future minimum rental payments due to the Company as lessor under operating leases as of June 30, 2016 (in thousands):   Remainder of 2016 $872,7262017 1,351,0702018 633,3422019 79,3552020 1,000Total $2,937,493Lease income for the three-month and six-month periods endedJune 30, 2016 were $460.1 million and $881.6 million, respectively, compared to $339.7 million and $653.1 million, respectively, for the three-month and six-month periods endedJune 30, 2015.Lease expense for three-month and six-month periods endedJune 30, 2016 were $322.2 million and $615.1 million, respectively, compared to $253.3 million and $494.3 million, respectively, for the three-month and six-month periods endedJune 30, 2015. |

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No definition available.
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| - Definition
The entire disclosure for operating leases of a lessor. This may include a general description of lessor's leasing arrangements for operating leases, including the basis on which contingent rental payments are determined, the existence and terms of renewal or purchase options and escalation clauses, restrictions imposed by lease arrangements, such as those concerning dividends, additional debt, and further leasing, rent holidays, rent concessions, or leasehold improvement incentives and unusual provisions or conditions.
+ References
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