| **FAIR VALUE (As Restated) (Fair Value Measurements, Recurring) (Details) - USD ($) $ in Thousands**                                                    | Jun. 30, 2015 | Dec. 31, 2014 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | $ 19,324,217  | $ 15,908,078  |
| Trading securities                                                                                                                                      | 0             | 833,936       |
| Retail installment contracts held for investment                                                                                                        | 494,700       | 845,900       |
| Mortgage servicing rights                                                                                                                               | 157,147       | 145,047       |
| Derivative assets at fair value                                                                                                                         | 391,300       | 366,061       |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 402,517       | 402,775       |
| US Treasury securities [Member]                                                                                                                         |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 2,601,882     | 1,695,767     |
| Corporate debt [Member]                                                                                                                                 |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 1,663,006     | 2,182,401     |
| Asset-backed securities [Member]                                                                                                                        |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 2,313,647     | 2,720,403     |
| Equity securities [Member]                                                                                                                              |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 10,411        | 10,343        |
| State and municipal securities [Member]                                                                                                                 |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 955,723       | 1,823,462     |
| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]                                                                                 |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 10,411        | 10,343        |
| Trading securities                                                                                                                                      |          | 0             |
| Loans held-for-sale                                                                                                                                     | 0             | 0             |
| Mortgage servicing rights                                                                                                                               | 0             | 0             |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Significant Other Observable Inputs (Level 2) [Member]                                                                                                  |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 17,774,323    | 14,630,092    |
| Trading securities                                                                                                                                      |          | 833,936       |
| Loans held-for-sale                                                                                                                                     | 1,948,742     | 260,251       |
| Mortgage servicing rights                                                                                                                               | 0             | 0             |
| Derivative assets at fair value                                                                                                                         | 405,047       | 384,100       |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 407,869       | 374,636       |
| Significant Unobservable Inputs (Level 3) [Member]                                                                                                      |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 1,539,483     | 1,267,643     |
| Trading securities                                                                                                                                      |          | 0             |
| Loans held-for-sale                                                                                                                                     | 0             | 0             |
| Mortgage servicing rights                                                                                                                               | 157,147       | 145,047       |
| Derivative assets at fair value                                                                                                                         | 1,903         | 3,070         |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 59,495        | 49,248        |
| Recurring [Member]                                                                                                                                      |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 19,324,217    | 15,908,078    |
| Trading securities                                                                                                                                      |          | 833,936       |
| Retail installment contracts held for investment                                                                                                        | 494,651       | 845,911       |
| Loans held-for-sale                                                                                                                                     | 364,910       | 213,666       |
| Mortgage servicing rights                                                                                                                               | 157,147       | 145,047       |
| Total financial assets                                                                                                                                  | 20,747,875    | 18,333,808    |
| **Financial liabilities:**                                                                                                                              |          |          |
| Total financial liabilities                                                                                                                             | 467,364       | 423,884       |
| Recurring [Member] | Mortgage banking interest rate lock commitments [Member]                                                                           |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 1,885         | 3,063         |
| Recurring [Member] | Mortgage banking forward sell commitments [Member]                                                                                 |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 6,511         |          |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             |          | 2,424         |
| Recurring [Member] | Customer related [Member]                                                                                                          |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 328,560       | 289,240       |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 291,244       | 252,955       |
| Recurring [Member] | Total return swap [Member]                                                                                                         |          |          |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 282           | 2,018         |
| Recurring [Member] | Foreign exchange [Member]                                                                                                          |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 25,974        | 20,033        |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 25,195        | 17,390        |
| Recurring [Member] | Mortgage servicing [Member]                                                                                                        |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 577           | 7,432         |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 11,028        | 7,448         |
| Recurring [Member] | Interest rate swap agreements [Member]                                                                                             |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 796           | 535           |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 10,118        | 12,743        |
| Recurring [Member] | Interest rate cap agreements [Member]                                                                                              |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 29,423        | 49,762        |
| Recurring [Member] | Option for interest rate cap [Member]                                                                                              |          |          |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 29,446        | 49,806        |
| Recurring [Member] | Total return settlement [Member]                                                                                                   |          |          |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 59,065        | 48,893        |
| Recurring [Member] | Other [Member]                                                                                                                     |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 7,902         | 6,543         |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 10,372        | 7,896         |
| Recurring [Member] | Fair value [Member]                                                                                                                |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 3,998         | 2,943         |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 2,702         | 1,759         |
| Recurring [Member] | Cash flow [Member]                                                                                                                 |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 1,324         | 7,619         |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 27,912        | 20,552        |
| Recurring [Member] | US Treasury securities [Member]                                                                                                    |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 2,601,882     | 1,695,767     |
| Recurring [Member] | Corporate debt [Member]                                                                                                            |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 1,663,006     | 2,182,401     |
| Recurring [Member] | Asset-backed securities [Member]                                                                                                   |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 2,313,647     | 2,720,403     |
| Recurring [Member] | Equity securities [Member]                                                                                                         |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 10,411        | 10,343        |
| Recurring [Member] | State and municipal securities [Member]                                                                                            |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 955,723       | 1,823,462     |
| Recurring [Member] | Mortgage backed securities [Member]                                                                                                |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 11,779,548    | 7,475,702     |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]                                                            |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 10,411        | 10,343        |
| Trading securities                                                                                                                                      |          | 0             |
| Retail installment contracts held for investment                                                                                                        | 0             | 0             |
| Loans held-for-sale                                                                                                                                     | 0             | 0             |
| Mortgage servicing rights                                                                                                                               | 0             | 0             |
| Total financial assets                                                                                                                                  | 10,411        | 10,343        |
| **Financial liabilities:**                                                                                                                              |          |          |
| Total financial liabilities                                                                                                                             | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Mortgage banking interest rate lock commitments [Member] |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Mortgage banking forward sell commitments [Member]       |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             |          |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             |          | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Customer related [Member]                                |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Total return swap [Member]                               |          |          |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Foreign exchange [Member]                                |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Mortgage servicing [Member]                              |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Interest rate swap agreements [Member]                   |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Interest rate cap agreements [Member]                    |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Option for interest rate cap [Member]                    |          |          |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Total return settlement [Member]                         |          |          |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Other [Member]                                           |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fair value [Member]                                      |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Cash flow [Member]                                       |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | US Treasury securities [Member]                          |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Corporate debt [Member]                                  |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Asset-backed securities [Member]                         |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Equity securities [Member]                               |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 10,411        | 10,343        |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | State and municipal securities [Member]                  |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 0             | 0             |
| Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Mortgage backed securities [Member]                      |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 0             | 0             |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]                                                                             |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 17,774,323    | 14,630,092    |
| Trading securities                                                                                                                                      |          | 833,936       |
| Retail installment contracts held for investment                                                                                                        | 0             | 0             |
| Loans held-for-sale                                                                                                                                     | 364,910       | 213,666       |
| Mortgage servicing rights                                                                                                                               | 0             | 0             |
| Total financial assets                                                                                                                                  | 18,544,280    | 16,061,794    |
| **Financial liabilities:**                                                                                                                              |          |          |
| Total financial liabilities                                                                                                                             | 407,869       | 374,636       |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Mortgage banking interest rate lock commitments [Member]                  |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Mortgage banking forward sell commitments [Member]                        |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 6,511         |          |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             |          | 2,424         |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Customer related [Member]                                                 |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 328,560       | 289,240       |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 291,244       | 252,955       |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Total return swap [Member]                                                |          |          |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 1,736         |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Foreign exchange [Member]                                                 |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 25,974        | 20,033        |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 25,195        | 17,390        |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Mortgage servicing [Member]                                               |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 577           | 7,432         |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 11,028        | 7,448         |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Interest rate swap agreements [Member]                                    |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 796           | 535           |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 10,118        | 12,743        |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Interest rate cap agreements [Member]                                     |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 29,423        | 49,762        |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Option for interest rate cap [Member]                                     |          |          |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 29,446        | 49,806        |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Total return settlement [Member]                                          |          |          |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Other [Member]                                                            |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 7,884         | 6,536         |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 10,224        | 7,823         |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Fair value [Member]                                                       |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 3,998         | 2,943         |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 2,702         | 1,759         |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Cash flow [Member]                                                        |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 1,324         | 7,619         |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 27,912        | 20,552        |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | US Treasury securities [Member]                                           |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 2,601,882     | 1,695,767     |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Corporate debt [Member]                                                   |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 1,663,006     | 2,182,401     |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Asset-backed securities [Member]                                          |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 774,164       | 1,452,760     |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Equity securities [Member]                                                |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 0             | 0             |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | State and municipal securities [Member]                                   |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 955,723       | 1,823,462     |
| Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Mortgage backed securities [Member]                                       |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 11,779,548    | 7,475,702     |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]                                                                                 |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 1,539,483     | 1,267,643     |
| Trading securities                                                                                                                                      |          | 0             |
| Retail installment contracts held for investment                                                                                                        | 494,651       | 845,911       |
| Loans held-for-sale                                                                                                                                     | 0             | 0             |
| Mortgage servicing rights                                                                                                                               | 157,147       | 145,047       |
| Total financial assets                                                                                                                                  | 2,193,184     | 2,261,671     |
| **Financial liabilities:**                                                                                                                              |          |          |
| Total financial liabilities                                                                                                                             | 59,495        | 49,248        |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Mortgage banking interest rate lock commitments [Member]                      |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 1,885         | 3,063         |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Mortgage banking forward sell commitments [Member]                            |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             |          |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             |          | 0             |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Customer related [Member]                                                     |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Total return swap [Member]                                                    |          |          |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 282           | 282           |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Foreign exchange [Member]                                                     |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Mortgage servicing [Member]                                                   |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Interest rate swap agreements [Member]                                        |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Interest rate cap agreements [Member]                                         |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Option for interest rate cap [Member]                                         |          |          |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Total return settlement [Member]                                              |          |          |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 59,065        | 48,893        |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Other [Member]                                                                |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 18            | 7             |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 148           | 73            |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair value [Member]                                                           |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Cash flow [Member]                                                            |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Derivative assets at fair value                                                                                                                         | 0             | 0             |
| **Financial liabilities:**                                                                                                                              |          |          |
| Derivatives                                                                                                                                             | 0             | 0             |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | US Treasury securities [Member]                                               |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 0             | 0             |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Corporate debt [Member]                                                       |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 0             | 0             |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Asset-backed securities [Member]                                              |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 1,539,483     | 1,267,643     |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Equity securities [Member]                                                    |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 0             | 0             |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | State and municipal securities [Member]                                       |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | 0             | 0             |
| Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Mortgage backed securities [Member]                                           |          |          |
| **Financial assets:**                                                                                                                                   |          |          |
| Available-for-sale investment securities                                                                                                                | $ 0           | $ 0           |

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| - Definition
Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.
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| - Definition
Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.
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| - Definition
Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.
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| - Definition
Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.
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| - Definition
Fair value of financial and nonfinancial obligations.
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| - Definition
Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.
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| - Definition
Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.
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| - Definition
Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.
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| - Definition
Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.
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