| **GOODWILL AND OTHER INTANGIBLES**                       | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
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| **Goodwill and Intangible Assets Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| GOODWILL AND OTHER INTANGIBLES                           | GOODWILL AND OTHER INTANGIBLESGoodwillDuring 2014, in connection with the Change in Control, the Company recorded goodwill of approximately $5.5 billion. In addition, the Company recorded a reduction of approximately $7.1 million of goodwill in connection with certain business disposal activities in January 2014. The Company evaluates goodwill for impairment at the reporting unit level. The fair value of the Company's reporting units is determined by using discounted cash flow and market comparability methodologies. Goodwill is assigned to reporting units, which are operating segments or one level below an operating segment, as of the acquisition date. As described in Note 24 to the Consolidated Financial Statements, during the second quarter of 2014, the Company reorganized its management reporting in order to improve its structure and focus by better aligning management teams and resources with the business goals of the Company and to provide enhanced customer service to its clients. Refer to Note 24 of the Consolidated Financial Statements for further discussion of the impact of the organizational changes on segment reporting. As a result of the change in segment reporting, the Company has also re-evaluated its conclusions related to goodwill reporting units. Upon evaluation, the Company has concluded that its reporting units will change consistently with the changes to segment reporting, including the following:•The Investment Services business unit is combined into the Retail Banking business unit.•The CEVF line, formerly included in the Specialty and Government Banking business unit, has been moved into the Auto Finance and Alliances business unit. There was no material goodwill associated with this change in reporting.•The Specialty and Government Banking business unit is combined into the Real Estate and Commercial Banking business unit.As of December 31, 2014, the reporting units with assigned goodwill were Retail Banking, Auto Finance & Alliances, Real Estate & Commercial Banking, GBM and SCUSA.NOTE 9. GOODWILL AND OTHER INTANGIBLES (continued)The following table presents activity in the Company's goodwill by its reporting units for the year ended December 31, 2014:   Retail Banking Investment Services Auto Finance & Alliances Real Estate and Commercial Banking Specialty & Government Banking Global Banking & Markets and Large Corporate SCUSA Total  (in thousands)Goodwill at December 31, 2013 $1,696,086 $126,695 $71,522 $1,163,154 $242,894 $131,130 $— $3,431,481Disposals during the period (7,052) — — — — — — $(7,052)Additions during the period — — —— — — 5,467,582 $5,467,582Re-allocations during the period 126,695 (126,695) — 242,894 (242,894) — — $—Goodwill at December 31, 2014 $1,815,729 $— $71,522 $1,406,048 $— $131,130 $5,467,582 $8,892,011Other Intangible AssetsThe following table details amounts related to the Company's finite-lived and indefinite-lived intangible assets for the dates indicated.  December 31, 2014 December 31, 2013 NetCarryingAmount AccumulatedAmortization NetCarryingAmount AccumulatedAmortization (in thousands)Intangibles subject to amortization:       Dealer networks$544,054 $(35,946) $— $—Chrysler Relationship125,000 (13,750) — —Core deposit intangibles7,779 (288,063) 22,650 (273,192)Other intangibles8,655 (21,253) 11,964 (17,945)Total intangibles subject to amortization685,488 (359,012) 34,614 (291,137)Intangibles not subject to amortization:       Trade name50,000 — — —Total Intangibles$735,488 $(359,012) $34,614 $(291,137)Amortization expense on intangible assets for 2014, 2013, and 2012 was $67.9 million, $27.3 million, and $37.2 million, respectively.The estimated aggregate amortization expense related to intangibles for each of the five succeeding calendar years ending December 31 is:Year Estimated Aggregated Amortization Expense  (in thousands)2015 64,4322016 57,1632017 55,0552018 54,702Thereafter 449,663 |

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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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