| **DERIVATIVES (Income Statement Effect) (Details) - USD ($) $ in Thousands** | 12 Months Ended |
|------------------------------------------------------------------------------|-----------------|
||
| Cross-currency swaps | Miscellaneous income | Fair value hedges              |            |   |   |
| **Derivative Instruments, Gain (Loss) [Line Items]**                         |            |   |   |
| Gain (loss) recognized on all derivatives                                    | $ 62            | $ 777 | $ 1,700 |
| Interest rate swaps | Miscellaneous income | Fair value hedges               |            |   |   |
| **Derivative Instruments, Gain (Loss) [Line Items]**                         |            |   |   |
| Gain (loss) recognized on all derivatives                                    | (1,412)         | (547) | 0 |
| Interest rate swaps | Net interest income | Cash flow hedges                 |            |   |   |
| **Derivative Instruments, Gain (Loss) [Line Items]**                         |            |   |   |
| Gain (loss) recognized on all derivatives                                    | (11,595)        | (53,112) | (65,900) |
| Forward commitments to sell loans | Mortgage banking income                  |            |   |   |
| **Derivative Instruments, Gain (Loss) [Line Items]**                         |            |   |   |
| Gain (loss) recognized on all derivatives                                    | 2,965           | (4,525) | 5,500 |
| Interest rate lock commitments | Mortgage banking income                     |            |   |   |
| **Derivative Instruments, Gain (Loss) [Line Items]**                         |            |   |   |
| Gain (loss) recognized on all derivatives                                    | (522)           | 2,516 | (14,900) |
| Mortgage servicing | Mortgage banking income                                 |            |   |   |
| **Derivative Instruments, Gain (Loss) [Line Items]**                         |            |   |   |
| Gain (loss) recognized on all derivatives                                    | (2,806)         | (5,683) | 6,500 |
| Customer related derivatives | Miscellaneous income                          |            |   |   |
| **Derivative Instruments, Gain (Loss) [Line Items]**                         |            |   |   |
| Gain (loss) recognized on all derivatives                                    | 3,191           | 9,605 | 17,200 |
| Foreign exchange | Miscellaneous income                                      |            |   |   |
| **Derivative Instruments, Gain (Loss) [Line Items]**                         |            |   |   |
| Gain (loss) recognized on all derivatives                                    | (2,525)         | 805 | (1,000) |
| SC Derivatives [Member] | Miscellaneous income                               |            |   |   |
| **Derivative Instruments, Gain (Loss) [Line Items]**                         |            |   |   |
| Gain (loss) recognized on all derivatives                                    | 11,913          | 30,330 | 0 |
| SC Derivatives [Member] | Net interest income                                |            |   |   |
| **Derivative Instruments, Gain (Loss) [Line Items]**                         |            |   |   |
| Gain (loss) recognized on all derivatives                                    | 78,640          | (5,226) | 0 |
| Other | Miscellaneous income                                                 |            |   |   |
| **Derivative Instruments, Gain (Loss) [Line Items]**                         |            |   |   |
| Gain (loss) recognized on all derivatives                                    | (1,129)         | (906) | 700 |
| Other | Net interest income                                                  |            |   |   |
| **Derivative Instruments, Gain (Loss) [Line Items]**                         |            |   |   |
| Gain (loss) recognized on all derivatives                                    | $ 0             | $ 0 | $ 3,100 |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5618551-113959Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a),(c),(d),(e) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959
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| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
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