| **OTHER ASSETS (As Restated)**                                                   | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
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| **Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| OTHER ASSETS (As Restated)                                                       | NOTE 9. OTHER ASSETS (As Restated)The following is a detail of items that comprise other assets at September 30, 2015 and December 31, 2014:  September 30, 2015 December 31, 2014  (in thousands)Income tax receivables $604,929 $938,222Derivative assets at fair value 415,409 366,061Other repossessed assets 154,434 136,305MSRs, at fair value 143,535 145,047Prepaid expenses 151,017 159,198OREO 40,692 65,051Miscellaneous assets and receivables 434,772 1,059,696Total other assets $1,944,788 $2,869,580Refer to Note 11 to the Condensed Consolidated Financial Statements for further details about derivative assets. Other repossessed assets primarily consist of SCUSA's vehicle inventory, which is obtained through repossession. OREO consists primarily of the Bank's foreclosed properties. Miscellaneous assets and receivables includes, but is not limited to, subvention receivables in connection with the Chrysler Agreement, investment and capital market receivables, and unapplied payments. Mortgage Servicing RightsThe Company maintains an MSR asset for sold residential real estate loans serviced for others. At both September 30, 2015 and December 31, 2014, the balance of these loans serviced for others was $15.9 billion. The Company accounts for residential MSRs using the FVO. Changes in fair value are recorded through the Condensed Consolidated Statements of Operations. The fair value of the MSRs at September 30, 2015 and December 31, 2014 was $143.5 million and $145.0 million, respectively. See further discussion on the valuation of the MSRs in Note 16. As deemed appropriate, the Company economically hedges MSRs using interest rate swaps and forward contracts to purchase mortgage-backed securities ("MBS"). See further discussion on these derivative activities in Note 11 to these Condensed Consolidated Financial Statements. For the three-month and nine-month periods endedSeptember 30, 2015, the Company recorded net changes in the fair value of MSRs totaling $(13.5) million and 0.7 million, respectively, compared to $(2.7) million and $(14.1) million for the corresponding periods of 2014. The MSR asset fair value decrease during the third quarter of 2015 was primarily the result of decreased interest rates.The following table presents a summary of year to date activity for the Company's residential MSRs that are included in the Condensed Consolidated Balance Sheet. Nine-Month Period Ended September 30, 2015 September 30, 2014 (in thousands)Fair value at beginning of period$145,047 $141,787Mortgage servicing assets recognized17,124 20,081Principal reductions(19,385) (15,999)Change in fair value due to valuation assumptions749 (14,078)Fair value at end of period$143,535 $131,791Multi-family Historically, the Company originated and sold multi-family loans in the secondary market to FNMA while retaining servicing. The Company has not sold multi-family loans to FNMA since 2009. At September 30, 2015 and December 31, 2014, the Company serviced $589.7 million and $2.6 billion, respectively, of loans for FNMA. NOTE 9. OTHER ASSETS (As Restated) (continued)Fee income and gain/loss on sale of mortgage loansIncluded in Mortgage banking income, net on the Condensed Consolidated Statement of Operations was mortgage servicing fee income of $11.1 million and $33.6 million for the three-month and nine-month periods endedSeptember 30, 2015, respectively, compared to $10.5 million and $31.7 million for the corresponding periods ended September 30, 2014. The Company had gains on sales of mortgage loans of $5.2 million and $28.7 million for the three-month and nine-month periods endedSeptember 30, 2015, respectively, compared to gains of $90.9 million and $104.7 million for the corresponding periods ended September 30, 2014. |

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| - Definition
The entire disclosure for other assets. This disclosure includes other current assets and other noncurrent assets.
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