| **COMMITMENTS, CONTINGENCIES, AND GUARANTEES (Tables)**  | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
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| **Commitments [Line Items]**                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Schedule of Commitments Amount                           | The following table details the amount of commitments at the dates indicated: Other Commitments March 31, 2015 December 31, 2014   (in thousands) Commitments to extend credit $28,676,743 $28,792,062 Unsecured revolving lines of credit — 5 Letters of credit 1,800,952 1,789,666 Recourse and credit enhancement exposure on sold loans 189,902 174,902 Commitments to sell loans 96,736 82,791 Total commitments $30,764,333 $30,839,426  |
| Schedule of Representation and Warranty Reserve Activity | The table below represents the activity in the representation and warranty reserve for the dates indicated.   Three-Month PeriodEnded March 31,   2015 2014  (in thousands)Beginning Balance $24,266 $54,836Changes in Estimate (569) 193Claims (646) (4,514)Ending Balance $23,051 $50,515                                                                                                                                                                                                            |
| Commitments to extend credit [Member]                    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| **Commitments [Line Items]**                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Schedule of Commitments, by Maturities                   | The following table details the amount of commitments to extend credit expiring per period as of the dates indicated:  March 31, 2015 December 31, 2014  (in thousands)One year or less $5,555,799 $5,968,468Over 1 year to 3 years 4,926,667 5,322,291Over 3 years to 5 years 11,473,813 10,810,213Over 5 years 6,720,464 6,691,090Total $28,676,743 $28,792,062                                                                                                                            |
| Letters of credit [Member]                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| **Commitments [Line Items]**                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Schedule of Commitments, by Maturities                   | The following table details the amount of letters of credit expiring per period as of the dates indicated:   March 31, 2015 December 31, 2014  (in thousands)One year or less $1,187,806 $1,250,124Over 1 year to 3 years 322,543 285,108Over 3 years to 5 years 261,579 248,209Over 5 years 29,024 6,225Total $1,800,952 $1,789,666                                                                                                                                                         |

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