| **BUSINESS COMBINATIONS**            | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  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| **Business Combinations [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          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| BUSINESS COMBINATIONS                | NOTE 3. BUSINESS COMBINATIONSGeneralOn January 28, 2014, the Company obtained a controlling financial interest in SCUSA in connection with the Change in Control. The financial information set forth in these Condensed Consolidated Financial Statements gives effect to the Company’s consolidation of SCUSA as a result of the Change in Control. Consolidated Assets acquired and Liabilities assumedThe Company did not incur any material transaction-related expenses in connection with the Change in Control, and no cash, equity interests, or other forms of consideration were transferred from the Company in connection with the Change in Control. As a result, the Company measured goodwill by reference to the fair value of SCUSA's equity as implied by the IPO price. The following table summarizes these equity related interests in SCUSA which constitute the purchase price and the identified assets acquired and liabilities assumed:  January 28, 2014  (in thousands)Fair value of noncontrolling interest in SCUSA $3,273,265Fair value of SCUSA employee vested stock options  210,181Fair value of SHUSA remaining ownership interest in SCUSA 5,063,881Fair value of equity-related interests in SCUSA $8,547,327   Recognized amounts of identifiable assets acquired and liabilities assumed:    Cash and cash equivalents $11,075Restricted cash 1,704,906Loan receivables - held for sale 990,137Loan receivables - retail installment contracts 19,870,790Loan receivables from dealers 102,689Loan receivables - unsecured 1,009,896Premises and equipment 74,998Leased vehicles, net 2,486,929Intangibles 768,750Miscellaneous receivables and other assets 1,061,351Deferred tax asset 16,399Borrowings and other debt obligations (24,497,607)Accounts payable and accrued liabilities (520,568)Total identifiable net assets 3,079,745   Goodwill $5,467,582NOTE 3. BUSINESS COMBINATIONS (continued)The fair value of the non-controlling interest ("NCI") of $3.3 billion and the fair value of the Company's remaining ownership interest in SCUSA of $5.1 billion were determined on the basis of the market price of SCUSA Common Stock on the Change in Control date.The Company recognized SCUSA’s stock option awards that were outstanding as of the IPO date at fair value, which in aggregate amounted to 369.3 million. The portion of the total fair value of the stock option awards that is attributable to pre-business combination service amounting to $210.2 million represented an NCI in SCUSA as of the IPO date, while 159.1 million of the total amount pertains to the post-business combination portion, which will be recognized as stock compensation expense over the remaining vesting period of the awards in the Company’s post-business combination consolidated financial statements. Of the total 159.1 million, 82.6 million was immediately recognized as stock compensation expense as a result of the acceleration of the vesting of certain of the stock option awards upon the closing of the IPO. The fair value of stock option awards was estimated using the Black-Scholes option valuation model. The Company also recognized SCUSA's restricted stock awards that were outstanding as of the IPO date at fair value. These shares of restricted stock were granted to certain SCUSA executives on December 28, 2013 and had an aggregate fair value of approximately 12.0 million as of the IPO date. The grant date fair value was determined based on SCUSA's per share prices as of the IPO closing date. The fair value of the assets acquired includes finance receivables. SHUSA estimated the fair value of loans acquired from SCUSA by utilizing a methodology in which similar loans were aggregated into pools. Cash flows for each pool were determined by estimating future credit losses and the rate of prepayments. Projected monthly cash flows were then discounted to present value based on a market rate for similar loans. There was no carryover of SCUSA's allowance for loan losses associated with the loans SHUSA acquired as the loans were initially recorded at fair value.   January 28, 2014  (in thousands)Fair value of loan receivables (1) $19,870,790Gross contractual amount of loan receivables (1) 31,410,699Estimate of contractual cash flows not expected to be collected at acquisition (1) 4,301,586   (1) Fair value of receivables does not include amounts related to the loan receivables - unsecured and loan receivables from dealers due to the short-term and revolving nature of the receivables.Goodwill recognized in connection with the Change in Control is attributable to SCUSA's workforce as well as the experience, proven track record, and strong capabilities of its senior management team. The goodwill associated with the Change in Control was allocated to the SCUSA segment and is not deductible for tax purposes.  January 28, 2014  Fair ValueWeighted Average Amortization Period  (dollars in thousands)Intangibles subject to amortization:   Dealer networks $580,00017.5 years (a)Chrysler relationship 138,7509.2 years    Intangibles not subject to amortization: Trade name 50,000indefinite livedTotal Intangibles $768,750    (a) The amortization periods of the dealer network range between 7 and 20 years.NOTE 3. BUSINESS COMBINATIONS (continued)Gain on Change in ControlThe Company recognized a pre-tax gain of $2.4 billion in connection with the Change in Control in Non-interest income in the Condensed Consolidated Statement of Operations.  January 28, 2014  (in thousands)   Gain attributable to SCUSA shares sold $137,536Gain attributable to the remaining equity interest 2,291,003Total pre-tax gain $2,428,539   In connection with the closing of the IPO on January 28, 2014, the Company sold 13,895,243 shares of SCUSA Common Stock, which generated proceeds of $320.1 million and a realized gain on sale of $137.5 million.Proforma Financial InformationThe results of SCUSA are included in the Company's results beginning January 28, 2014. The following table summarizes the actual unaudited amounts of Total revenue, net of Total interest expense and Net income including Noncontrolling Interest of SCUSA included in the Condensed Consolidated Financial Statements for the three-month and nine-month periods endedSeptember 30, 2014 and the supplemental pro forma consolidated Total revenue, net of total interest expense and Net income including noncontrolling interest of SHUSA entity for the three-month and nine-month periods endedSeptember 30, 2014 as if the Change in Control had occurred on January 1, 2013. These results include the impact of amortizing certain purchase accounting adjustments such as intangible assets as well as fair value adjustments to loans and issued debt. These pro forma results are presented for illustrative purposes and are not intended to represent or be indicative of the actual consolidated results of operations of SHUSA that would have been achieved had the Change in Control occurred at January 1, 2013, nor are they intended to represent or be indicative of future results of operations.   SCUSA Amounts Included in Results for the Supplemental Pro Forma Combined (b)  Three-Month Period Ended September 30, 2014 Nine-Month Period Ended September 30, 2014 Three-Month Period Ended September 30, 2014 Nine-Month Period Ended September 30, 2014  (in thousands)         Total Revenue, Net of Total Interest Expense (a) $1,585,281 $4,281,311 $2,232,312 $6,239,871Net Income including Noncontrolling Interest 136,237 710,984 289,417 655,055         (a) Total Revenue, Net of Total Interest Expense is calculated as the sum of Total Interest Income and Total Non-Interest Income, less Total Interest Expense.(b) Includes the impact of recording provision for loan losses necessary to bring the retail installment contracts and personal unsecured loans to their expected carrying values considering the required allowance for loan losses on their recorded investment amounts. These amounts have been calculated after applying SHUSA's accounting policies and adjusting the results of SCUSA to reflect additional depreciation and amortization that would have been charged assuming the fair value adjustments to loans, debt, premises and equipment had been applied from January 1, 2013 with the consequential tax effects. |

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| - Definition
The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).
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