| **GOODWILL AND OTHER INTANGIBLES (As Restated)**         | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
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| **Goodwill and Intangible Assets Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| GOODWILL AND OTHER INTANGIBLES (As Restated)             | NOTE 8. GOODWILL AND OTHER INTANGIBLES (As Restated)GoodwillThe following table presents activity in the Company's goodwill by its reportable segments for the nine-month period endedSeptember 30, 2015:  Retail Banking Auto Finance & Business Banking(2) Real Estate and Commercial Banking Global Corporate Banking(1) SCUSA Total  (in thousands)Goodwill at December 31, 2014 $1,815,729 $71,522 $1,406,048 $131,130 $5,527,055 $8,951,484Disposals during the period — — — —  —Additions during the period — — — — — —Re-allocations during the period (265,553) 374,546 (108,993) — — —Goodwill at September 30, 2015 $1,550,176 $446,068 $1,297,055 $131,130 $5,527,055 $8,951,484(1) The Global Corporate Banking ("GCB") was formerly designated as the Global Corporate Banking & Market & Large Corporate Banking segment and was renamed during the third quarter of 2015.(2) The Auto Finance & Business Banking was formerly designated as the Auto Finance and Alliances segment and was renamed during the third quarter of 2015.The Company evaluates goodwill for impairment at least annually, or more frequently as required by events and circumstances. For the purposes of testing goodwill for impairment, goodwill is assigned to reporting units, which are operating segments or one level below an operating segment, as of the acquisition date. The fair value of the Company's reporting unit is determined by using discounted cash flow ("DCF") and market comparability methodologies.The goodwill for the SCUSA reporting unit, as restated at December 31, 2014, reflects an increase of $59.5 million from the restatement as a result of the increased value of the SCUSA business at acquisition. In connection with these and other organizational changes discussed in Note 17, the Company engaged a valuation consultant to assist with the re-allocation of goodwill across its reporting units based on the fair value of the lines of business affected by the re-organization. The Company’s accounting policy provides that changes in segment reporting are point in time reporting events, which would only require (where practicable) a retrospective change in the segments’ financial information. Accordingly, this change does not impact the disclosure of the Company's goodwill by reportable segment within its consolidated financial statements for periods prior to the segment changes.NOTE 8. GOODWILL AND OTHER INTANGIBLES (As Restated) (continued)Other Intangible AssetsThe following table details amounts related to the Company's finite-lived and indefinite-lived intangible assets for the dates indicated.  September 30, 2015 December 31, 2014 NetCarryingAmount AccumulatedAmortization NetCarryingAmount AccumulatedAmortization     (in thousands)Intangibles subject to amortization:       Dealer networks$514,643 $(65,357) $544,054 $(35,946)Chrysler relationship113,750 (25,000) 125,000 (13,750)Core deposit intangibles1,830 (294,012) 7,779 (288,063)Other intangibles6,234 (23,675) 8,655 (21,253)Total intangibles subject to amortization636,457 (408,044) 685,488 (359,012)Intangibles not subject to amortization:       Trade name21,500 — 21,500 —Total Intangibles$657,957 $(408,044) $706,988 $(359,012)Amortization expense on intangible assets for the three-month and nine-month periods endedSeptember 30, 2015 was $15.9 million and $49.0 million, respectively, compared to $17.7 million and $50.7 million for the corresponding periods in 2014.During the fourth quarter of 2014, the Company's intangible impairment analysis concluded that the estimated fair value of the indefinite-lived trade name was lower than its carrying value. As a result, the Company recorded an impairment charge of $28.5 million. The estimated aggregate amortization expense related to intangibles for each of the five succeeding calendar years ending December 31 is:Year Calendar Year Amount Recorded To Date Remaining Amount To Record  (in thousands)2015 $64,432 $49,031 $15,4012016 57,162 — 57,1622017 55,055 — 55,0552018 54,702 — 54,7022019 54,501 — 54,501Thereafter 399,636 — 399,636 |

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| - Definition
The entire disclosure for the aggregate amount of goodwill and a description of intangible assets, which may include (a) for amortizable intangible assets (also referred to as finite-lived intangible assets), the carrying amount, the amount of any significant residual value, and the weighted-average amortization period, (b) for intangible assets not subject to amortization (also referred to as indefinite-lived intangible assets), the carrying amount, and (c) the amount of research and development assets acquired and written off in the period, including the line item in the income statement in which the amounts written off are aggregated, if not readily apparent from the income statement. Also discloses (a) for amortizable intangibles assets in total and by major class, the gross carrying amount and accumulated amortization, the total amortization expense for the period, and the estimated aggregate amortization expense for each of the five succeeding fiscal years, (b) for intangible assets not subject to amortization the carrying amount in total and by major class, and (c) for goodwill, in total and for each reportable segment, the changes in the carrying amount of goodwill during the period (including the aggregate amount of goodwill acquired, the aggregate amount of impairment losses recognized, and the amount of goodwill included in the gain (loss) on disposal of a reporting unit). If any part of goodwill has not been allocated to a reportable segment, discloses the unallocated amount and the reasons for not allocating. For each impairment loss recognized related to an intangible asset (excluding goodwill), discloses: (a) a description of the impaired intangible asset and the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method for determining fair value, (c) the caption in the income statement or the statement of activities in which the impairment loss is aggregated, and (d) the segment in which the impaired intangible asset is reported. For each goodwill impairment loss recognized, discloses: (a) a description of the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method of determining the fair value of the associated reporting unit, and (c) if a recognized impairment loss is an estimate not finalized and the reasons why the estimate is not final.  May also disclose the nature and amount of any significant adjustments made to a previous estimate of an impairment loss.
+ References
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