| **OTHER ASSETS**                                                                 | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
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| **Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| OTHER ASSETS                                                                     | OTHER ASSETSThe following is a detail of items that comprise other assets at June 30, 2016 and December 31, 2015:  June 30, 2016 December 31, 2015  (in thousands)Income tax receivables $419,396 $613,339Derivative assets at fair value 555,127 355,169Other repossessed assets 186,202 172,749MSRs, at fair value 117,792 147,233Prepaid expenses 171,928 162,879OREO 37,432 38,959Miscellaneous assets and receivables 482,447 403,487Total other assets $1,970,324 $1,893,815Derivative assets at fair value represent the net amount of derivatives presented in the Condensed Consolidated Financial Statements, including the impact of amounts offsetting recognized assets. Refer to the offsetting of financial assets table in Note 11 to these Condensed Consolidated Financial Statements for the detail of these amounts.The change in income tax receivable is related to the receipt of an IRS refund in the second quarter of 2016.MSRsResidential real estateThe Company maintains an MSR asset for sold residential real estate loans serviced for others. At June 30, 2016 and December 31, 2015, the balance of these loans serviced for others was $15.6 billion, and $15.9 billion, respectively. The Company accounts for residential MSRs using the FVO. Changes in fair value are recorded through the Mortgage banking income, net line of the Condensed Consolidated Statements of Operations. The fair value of the MSRs at June 30, 2016 and December 31, 2015 were $117.8 million and $147.2 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 MBS. See further discussion on these derivative activities in Note 11 to these Condensed Consolidated Financial Statements. For the three-month and six-month periods endedJune 30, 2016, the Company recorded net changes in the fair value of MSRs due to valuation totaling $(11.5) million and $(25.8) million, respectively, compared to $21.2 million and $14.2 million for the corresponding periods in 2015.The following table presents a summary of activity for the Company's residential MSRs that are included in the Condensed Consolidated Balance Sheets. Three-Month Period Ended Six-Month Period Ended June 30, 2016 June 30, 2015 June 30, 2016 June 30, 2015 (in thousands)Fair value at beginning of period$130,742 $135,452 $147,233 $145,047Mortgage servicing assets recognized4,801 7,803 8,392 11,329Principal reductions(6,283) (7,319) (12,009) (13,450)Change in fair value due to valuation assumptions(11,468) 21,211 (25,824) 14,221Fair value at end of period$117,792 $157,147 $117,792 $157,147NOTE 8. OTHER ASSETS (continued)Fee income and gain/loss on sale of mortgage loansIncluded in Mortgage banking income, net on the Condensed Consolidated Statements of Operations was mortgage servicing fee income of $10.8 million and $21.6 million for the three-month and six-month periods endedJune 30, 2016, respectively, compared to $11.3 million and $22.5 million for the corresponding periods in 2015. The Company had gains on sales of mortgage loans included in Mortgage banking income, net on the Condensed Consolidated Statements of Operations of $6.6 million and $9.7 million for the three-month and six-month periods endedJune 30, 2016, respectively, compared to gains of $17.4 million and $23.6 million for the corresponding periods ended June 30, 2015.Other repossessed assets and Other Real Estate Owned (“OREO")Other repossessed assets primarily consist of SC's vehicle inventory, which is obtained through repossession. Other real estate owned ("OREO") consists primarily of the Bank's foreclosed properties. Miscellaneous assets and receivablesMiscellaneous 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. This increased due to an increase in capitalized lease equipment. |

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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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