|**COMMITMENTS, CONTINGENCIES, AND GUARANTEES (Tables)**                                                                                                 | 9 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 CommitmentsSeptember 30, 2014December 31, 2013(in thousands)Commitments to extend credit$27,557,412$23,651,791Unsecured revolving lines of credit2,298,694815,573Letters of credit2,010,0162,116,227Recourse and credit enhancement exposure on sold loans176,247184,584Commitments to sell loans95,9433,810Total commitments$32,138,312$26,771,985                                                                                                 
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|Other Commitments                                                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
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|Commitments to extend credit                                                                                                                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Unsecured revolving lines of credit                                                                                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Letters of credit                                                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Recourse and credit enhancement exposure on sold loans                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Commitments to sell loans                                                                                                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Total commitments                                                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|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 September 30,Nine-Month PeriodEnded September 30,2014201320142013(in thousands)Beginning Balance$40,862$56,221$54,836$50,662Additions(1)10,8942,4873,31518,280Reductions(794)(2,769)(7,189)(13,003)Ending Balance$50,962$55,939$50,962$55,939(1)- The additions for the nine-month period ended September 30, 2014 includes the $8.0 million reduction in the representation and warranty liability.
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|Beginning Balance                                                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Additions(1)                                                                                                                                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Reductions                                                                                                                                              |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Ending Balance                                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|(1)- The additions for the nine-month period ended September 30, 2014 includes the $8.0 million reduction in the representation and warranty liability. |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|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:September 30, 2014December 31, 2013(in thousands)One year or less$5,289,599$5,163,591Over 1 year to 3 years5,917,7055,716,759Over 3 years to 5 years9,911,4066,457,992Over 5 years6,438,7026,313,449Total$27,557,412$23,651,791                                                                                                                                                                                   
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|One year or less                                                                                                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Over 1 year to 3 years                                                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Over 3 years to 5 years                                                                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Over 5 years                                                                                                                                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Total                                                                                                                                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|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:September 30, 2014December 31, 2013(in thousands)One year or less$1,450,905$1,680,277Over 1 year to 3 years295,290333,769Over 3 years to 5 years256,92896,558Over 5 years6,8935,623Total$2,010,016$2,116,227                                                                                                                                                                                                                 
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|One year or less                                                                                                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Over 1 year to 3 years                                                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Over 3 years to 5 years                                                                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Over 5 years                                                                                                                                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Total                                                                                                                                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        

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