| **LEASED VEHICLES, NET** | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|--------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
||
| **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 Chrysler Capital consumer vehicle lease applications. SC provides servicing on all leases originated under this agreement.Leased vehicles, net consisted of the following as of March 31, 2016 and December 31, 2015:  March 31, 2016 December 31, 2015  (in thousands)Leased vehicles $12,284,996 $11,332,226Origination fees and other costs 30,127 29,798Manufacturer subvention payments, net of accretion (1,153,958) (1,061,501)Leased vehicles, gross 11,161,165 10,300,523Less: accumulated depreciation (2,180,635) (1,911,693)Leased vehicles, net $8,980,530 $8,388,830During the first quarter of 2016, the Company did not execute any bulk sales of leases originated under the Chrysler Capital program ("Chrysler Capital"), the trade name used in providing services under the Chrysler Agreement. During the first quarter of 2015, the Company executed a bulk sale of leases originated under the Chrysler Capital program with depreciated net capitalized costs of $561.3 million and a net book value of $488.9 million 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 gain 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 March 31, 2016 (in thousands):    Remainder of 2016 $1,192,9762017 1,138,5412018 444,7672019 24,1732020 50Total $2,800,507Lease income and expense for the three-month period endedMarch 31, 2016 were $434.7 million and $293.8 million, respectively, compared to $312.3 million and $235.9 million, respectively, for the three-month period endedMarch 31, 2015. |

| X                                                                                                                                                                                        |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - References
No definition available.
+ Details**Name:**us-gaap_LeasesAbstract**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6453916&loc=d3e41457-112716Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6453916&loc=d3e41460-112716Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6452767&loc=d3e37051-112695Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=51678428&loc=d3e61901-109447Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6452767&loc=d3e37045-112695
+ Details**Name:**us-gaap_OperatingLeasesOfLessorDisclosureTextBlock**Namespace Prefix:**us-gaap_**Data Type:**nonnum:textBlockItemType**Balance Type:**na**Period Type:**duration |