| **BASIS OF PRESENTATION AND ACCOUNTING POLICIES (Narrative) (Details) $ / shares in Units, $ in Thousands**    | 3 Months Ended | 12 Months Ended |             |
|----------------------------------------------------------------------------------------------------------------|----------------|-----------------|-------------|
||
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Debt issuance costs resulting from adoption of ASU                                                             | $ 59,000       |            | $ 59,000    | $ 30,300 |   |   |
| FHLB Stock, par value (in usd per share) | $ / shares                                                          | $ 100          |            | $ 100       |   |   |   |
| TDR, threshold period of sustained repayment performance                                                       |           |            | 6 months    |   |   |   |
| Period of time not resulting loan identified as impaired (less than)                                           |           |            | 90 days     |   |   |   |
| Impaired financing receivable, unpaid principal balance (in excess of)                                         | $ 5,044,479    |            | $ 5,044,479 | 2,898,294 |   |   |
| Number of LTV bands | band                                                                                     |           |            | 6           |   |   |   |
| Delinquency period for operating leases (more than)                                                            |           |            | 60 days     |   |   |   |
| Impairment of goodwill                                                                                         | 4,500,000      |            | $ 4,507,095 | 0 | $ 0 |   |
| Past due period for repossession                                                                               |           |            | 60 days     |   |   |   |
| OREO and other repossessed assets                                                                              | 211,700        |            | $ 211,700   | 201,400 |   |   |
| SC                                                                                                             |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Intangibles                                                                                                    | 768,800        |            | $ 768,800   |   |   | $ 768,750 |
| Retail installment contracts                                                                                   |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Financing receivable, nonaccrual status, threshold period past due                                             |           |            | 60 days     |   |   |   |
| TDR, nonaccrual status, threshold period past due                                                              |           |            | 60 days     |   |   |   |
| Period of time not resulting loan identified as impaired (less than)                                           |           |            | 61 days     |   |   |   |
| Commercial Loans and Consumer Loans [Member]                                                                   |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Financing receivable, nonaccrual status, threshold period past due                                             |           |            | 90 days     |   |   |   |
| Consumer Loan [Member]                                                                                         |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Threshold period past due for write-off of financing receivable                                                |           |            | 180 days    |   |   |   |
| Consumer loans not secured by real estate                                                                      |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Threshold period past due for write-off of financing receivable                                                |           |            | 120 days    |   |   |   |
| Auto Loans                                                                                                     |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Threshold period past due for write-off of financing receivable                                                |           |            | 120 days    |   |   |   |
| Retail installment contracts                                                                                   |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Threshold period past due for write-off of financing receivable                                                |           |            | 120 days    |   |   |   |
| Unsecured Debt [Member]                                                                                        |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Threshold period past due for write-off of financing receivable                                                |           |            | 180 days    |   |   |   |
| Personal unsecured loans                                                                                       |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Threshold period past due for write-off of financing receivable                                                |           |            | 180 days    |   |   |   |
| Credit Card Receivable [Member]                                                                                |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Financing receivable, nonaccrual status, threshold period past due                                             |           |            | 180 days    |   |   |   |
| Financing receivable, nonaccrual status, threshold period after receipt of notification of death or bankruptcy |           |            | 60 days     |   |   |   |
| Home Equity Loan [Member]                                                                                      |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Threshold period past due for write-off of financing receivable                                                |           |            | 180 days    |   |   |   |
| Residential mortgages                                                                                          |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Threshold period past due for write-off of financing receivable                                                |           |            | 180 days    |   |   |   |
| Retail installment contracts and auto loans                                                                    |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Threshold period past due for write-off of financing receivable                                                |           |            | 120 days    |   |   |   |
| Term Loan [Member]                                                                                             |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Threshold period past due for write-off of financing receivable                                                |           |            | 120 days    |   |   |   |
| Minimum | Commercial Loan [Member]                                                                             |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Impaired financing receivable, unpaid principal balance (in excess of)                                         | 1,000          |            | $ 1,000     |   |   |   |
| Trade name                                                                                                     |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Impairment of intangible assets                                                                                | $ 3,500        |            | $ 3,500     | $ 28,500 |   |   |
| Office Building [Member] | Minimum                                                                             |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Estimated useful lives                                                                                         |           |            | 10 years    |   |   |   |
| Office Building [Member] | Maximum                                                                             |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Estimated useful lives                                                                                         |           |            | 30 years    |   |   |   |
| Software [Member] | Minimum                                                                                    |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Estimated useful lives                                                                                         |           |            | 3 years     |   |   |   |
| Software [Member] | Maximum                                                                                    |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Estimated useful lives                                                                                         |           |            | 5 years     |   |   |   |
| Leasehold Improvements [Member] | Minimum                                                                      |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Estimated useful lives                                                                                         |           |            | 10 years    |   |   |   |
| Leasehold Improvements [Member] | Maximum                                                                      |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Estimated useful lives                                                                                         |           |            | 30 years    |   |   |   |
| Furniture, Fixtures and Equipment [Member] | Minimum                                                           |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Estimated useful lives                                                                                         |           |            | 3 years     |   |   |   |
| Furniture, Fixtures and Equipment [Member] | Maximum                                                           |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Estimated useful lives                                                                                         |           |            | 10 years    |   |   |   |
| Automobiles [Member]                                                                                           |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Estimated useful lives                                                                                         |           |            | 5 years     |   |   |   |
| Scenario, Forecast                                                                                             |           |            |        |   |   |   |
| **Basis of Presentation and Accounting Policies [Line Items]**                                                 |           |            |        |   |   |   |
| Impairment of goodwill                                                                                         |           | $ 1,000,000     |        |   |   |   |
| Impairment of intangible assets                                                                                |           | $ 38,000        |        |   |   |   |

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[Line Items] for Basis of Presentation and Accounting Policies [Table]
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Federal Home Loan Bank Stock, par value
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Financing Receivable, Nonaccrual Status, Threshold Period Past Due
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Financing Receivable, Nonaccrual Status, Threshold Period after Receipt of Notification of Death or Bankruptcy
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Financing Receivable, Number of Loan to Value Bands
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Financing Receivables, Modifications, Threshold Period of Sustained Repayment Performance
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Operating Leases, Lease Revenue, Delinquency Period
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| - Definition
Other Real Estate, Foreclosed Assets, and Repossessed Assets, Past Due Period
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| - Definition
Period of Time Not Resulting Loan Identified as Impaired
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Troubled Debt Restructuring, Nonaccrual Status, Threshold Period Past Due
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| - Definition
Amount of intangible assets, excluding goodwill, acquired at the acquisition date.
+ References
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| - Definition
Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
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| - Definition
Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.
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| - Definition
Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.
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| - Definition
Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.
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| - Definition
Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.
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| - Definition
Threshold period past due for financing receivable to write off as uncollectible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
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| - Definition
The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.
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