| **BORROWINGS (SCUSA) (Details) - USD ($) $ in Thousands**                                                                  | 3 Months Ended | 12 Months Ended |
|----------------------------------------------------------------------------------------------------------------------------|----------------|-----------------|
||
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | $ 80,300       | $ 58,800        |
| SCUSA [Member]                                                                                                             |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | 36,005,751     | 35,182,041      |
| Restricted Cash Pledged                                                                                                    | $ 1,624,242    | $ 1,465,085     |
| SCUSA [Member] | Minimum [Member]                                                                                          |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Effective Rate                                                                                                             | 0.89%          | 0.89%           |
| SCUSA [Member] | Maximum [Member]                                                                                          |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Effective Rate                                                                                                             | 2.02%          | 2.80%           |
| SCUSA [Member] | Revolving Credit Facility [Member]                                                                        |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | $ 11,413,550   | $ 9,792,327     |
| Effective Rate                                                                                                             | 1.68%          | 1.68%           |
| Assets Pledged                                                                                                             | $ 8,474,687    | $ 6,968,449     |
| Restricted Cash Pledged                                                                                                    | 235,018        | 197,854         |
| SCUSA [Member] | Revolving Credit Facility [Member] | Warehouse Line due on Various Dates [Member]                         |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | $ 890,965      | $ 397,452       |
| Effective Rate                                                                                                             | 1.00%          | 1.26%           |
| Assets Pledged                                                                                                             | $ 1,305,875    | $ 589,529       |
| Restricted Cash Pledged                                                                                                    | 32,484         | 20,661          |
| SCUSA [Member] | Revolving Credit Facility [Member] | Warehouse Line due May 2015 [Member]                                 |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | $ 250,594      |            |
| Effective Rate                                                                                                             | 1.02%          |            |
| Assets Pledged                                                                                                             | $ 0            |            |
| Restricted Cash Pledged                                                                                                    | 0              |            |
| SCUSA [Member] | Revolving Credit Facility [Member] | Warehouse Line due June 2015 [Member]                                |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | $ 388,435      | $ 243,736       |
| Effective Rate                                                                                                             | 0.98%          | 1.17%           |
| Assets Pledged                                                                                                             | $ 558,135      | $ 344,822       |
| Restricted Cash Pledged                                                                                                    | 0              | 0               |
| SCUSA [Member] | Revolving Credit Facility [Member] | Warehouse Line due September 2015 [Member]                           |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | $ 199,980      | $ 199,980       |
| Effective Rate                                                                                                             | 2.00%          | 1.96%           |
| Assets Pledged                                                                                                             | $ 351,512      | $ 351,755       |
| Restricted Cash Pledged                                                                                                    | 15,926         | 13,169          |
| SCUSA [Member] | Revolving Credit Facility [Member] | Warehouse Line due June 2016 with Chrysler Capital [Member]          |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | $ 2,465,041    | $ 2,201,511     |
| Effective Rate                                                                                                             | 0.93%          | 0.98%           |
| Assets Pledged                                                                                                             | $ 3,719,820    | $ 3,249,263     |
| Restricted Cash Pledged                                                                                                    | 85,180         | 65,414          |
| SCUSA [Member] | Revolving Credit Facility [Member] | Warehouse Line due October 2016 [Member]                             |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | $ 249,987      | $ 240,487       |
| Effective Rate                                                                                                             | 2.05%          | 2.02%           |
| Assets Pledged                                                                                                             | $ 308,279      | $ 299,195       |
| Restricted Cash Pledged                                                                                                    | 19,139         | 17,143          |
| SCUSA [Member] | Revolving Credit Facility [Member] | Warehouse Line due November 2016 [Member]                            |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | $ 175,000      | $ 175,000       |
| Effective Rate                                                                                                             | 1.73%          | 1.71%           |
| Assets Pledged                                                                                                             | $ 0            | $ 0             |
| Restricted Cash Pledged                                                                                                    | 0              | 0               |
| SCUSA [Member] | Revolving Credit Facility [Member] | Warehouse Line due November 2016 [Member]                            |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | $ 250,000      | $ 250,000       |
| Effective Rate                                                                                                             | 1.73%          | 1.71%           |
| Assets Pledged                                                                                                             | $ 0            | $ 0             |
| Restricted Cash Pledged                                                                                                    | 2,500          | 2,500           |
| SCUSA [Member] | Revolving Credit Facility [Member] | Warehouse Line due December 2016 [Member]                            |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | $ 1,575,977    |            |
| Effective Rate                                                                                                             | 1.05%          |            |
| Assets Pledged                                                                                                             | $ 2,222,916    |            |
| Restricted Cash Pledged                                                                                                    | 46,853         |            |
| SCUSA [Member] | Revolving Credit Facility [Member] | Warehouse Line due March 2015 [Member]                               |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    |           | $ 250,594       |
| Effective Rate                                                                                                             |           | 0.98%           |
| Assets Pledged                                                                                                             |           | $ 0             |
| Restricted Cash Pledged                                                                                                    |           | 0               |
| SCUSA [Member] | Revolving Credit Facility [Member] | Warehouse Line due December 2015 [Member]                            |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    |           | $ 468,565       |
| Effective Rate                                                                                                             |           | 0.93%           |
| Assets Pledged                                                                                                             |           | $ 641,709       |
| Restricted Cash Pledged                                                                                                    |           | 16,467          |
| SCUSA [Member] | Revolving Credit Facility [Member] | Warehouse Line due June 2016 [Member]                                |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    |           | $ 1,051,777     |
| Effective Rate                                                                                                             |           | 1.06%           |
| Assets Pledged                                                                                                             |           | $ 1,481,135     |
| Restricted Cash Pledged                                                                                                    |           | 28,316          |
| SCUSA [Member] | Revolving Credit Facility [Member] | Repurchase Facility due on Various Dates [Member]                    |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | $ 892,571      | $ 923,225       |
| Effective Rate                                                                                                             | 1.64%          | 1.63%           |
| Assets Pledged                                                                                                             | $ 0            | $ 0             |
| Restricted Cash Pledged                                                                                                    | $ 32,936       | $ 34,184        |
| SCUSA [Member] | Revolving Credit Facility [Member] | Repurchase Facility due on Various Dates [Member] | Minimum [Member] |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Facility rolling maturity period                                                                                           | 30 days        | 30 days         |
| SCUSA [Member] | Revolving Credit Facility [Member] | Repurchase Facility due on Various Dates [Member] | Maximum [Member] |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Facility rolling maturity period                                                                                           | 90 days        | 90 days         |
| SCUSA [Member] | Revolving Credit Facility [Member] | Line of Credit with Related Party due December 2016 [Member]         |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | $ 500,000      | $ 500,000       |
| Effective Rate                                                                                                             | 2.47%          | 2.46%           |
| Assets Pledged                                                                                                             | $ 1,074        | $ 1,340         |
| Restricted Cash Pledged                                                                                                    | 0              | 0               |
| SCUSA [Member] | Revolving Credit Facility [Member] | Line of Credit with Related Party due December 2016 [Member]         |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | $ 1,750,000    | $ 1,750,000     |
| Effective Rate                                                                                                             | 2.36%          | 2.33%           |
| Assets Pledged                                                                                                             | $ 0            | $ 0             |
| Restricted Cash Pledged                                                                                                    | 0              | 0               |
| SCUSA [Member] | Revolving Credit Facility [Member] | Line of Credit with Related Party due December 2018 [Member]         |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | $ 250,000      |            |
| Effective Rate                                                                                                             | 3.23%          |            |
| Assets Pledged                                                                                                             | $ 0            |            |
| Restricted Cash Pledged                                                                                                    | 0              |            |
| SCUSA [Member] | Revolving Credit Facility [Member] | Line of Credit with Related Party due December 2018 [Member]         |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Balance                                                                                                                    | $ 1,575,000    | $ 1,140,000     |
| Effective Rate                                                                                                             | 2.82%          | 2.85%           |
| Assets Pledged                                                                                                             | $ 7,076        | $ 9,701         |
| Restricted Cash Pledged                                                                                                    | 0              | 0               |
| SCUSA [Member] | Revolving Credit Facility [Member] | Line of Credit with Related Party [Member]                           |           |            |
| **Debt Instrument [Line Items]**                                                                                           |           |            |
| Unsecured debt                                                                                                             | $ 2,700,000    | $ 2,200,000     |

| X                                                                                                                                                                                                                                                                                                                                                                                                  |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Pledged Restricted Cash Separately Reported Securities Pledged Under Letter Of Credit Facilities At Fair Value
+ References
No definition available.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399
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| X                                                                                                                                                                                                                                                                                                                                                                                                               |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 20, 22 -Article 5
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| X                                                                                                                                                                                                                                                                                                                                                                                                                             |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The fair value, as of the date of each statement of financial position presented, of securities that are restricted as collateral under letter of credit agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Article 5 -Subsection 19, 20, 22
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| X                                                                                                                           |
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