| **LOANS AND ALLOWANCE FOR CREDIT LOSSES (Troubled Debt Restructuring Activity) (Details) $ in Thousands** | 3 Months Ended | 9 Months Ended |             |
|-----------------------------------------------------------------------------------------------------------|----------------|----------------|-------------|
||
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Troubled debt restructurings                                                                              | $ 6,901,473    |           | $ 6,901,473 |   | $ 6,106,915 |
| Number of Contracts | contract                                                                            | 70,524         | 55,248         | 175,935     | 164,797 |   |
| Pre-TDR Recorded Investment                                                                               | $ 1,189,858    | $ 989,593      | $ 3,112,910 | $ 2,771,966 |   |
| Post-TDR Recorded Investment                                                                              | $ 1,187,993    | $ 998,364      | $ 3,081,568 | $ 2,782,584 |   |
| **TDRs which Subsequently Defaulted**                                                                     |           |           |        |   |   |
| Number of Contracts | contract                                                                            | 12,136         | 13,194         | 37,546      | 39,426 |   |
| Recorded Investment                                                                                       | $ 218,369      | $ 217,612      | $ 650,013   | $ 619,792 |   |
| Term Extension                                                                                            |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 1,227          | 903            | 17,226      | 2,193 |   |
| Capitalized                                                                                               |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | (358)          |           | (699)       |   |   |
| Rate Reduction                                                                                            |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | (260)       |   |   |
| Principal Forbearance                                                                                     |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 2              | 1,342          | 13,483      | 27,198 |   |
| Fee Waiver                                                                                                |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 38          |   |   |
| Other                                                                                                     |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | $ 994          | $ (11,016)     | $ 1,554     | $ (40,009) |   |
| Commercial | Corporate banking                                                                            |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Number of Contracts | contract                                                                            | 18             | 21             | 72          | 81 |   |
| Pre-TDR Recorded Investment                                                                               | $ 4,632        | $ 53,849       | $ 143,976   | $ 213,688 |   |
| Post-TDR Recorded Investment                                                                              | 4,505          | 49,590         | 116,490     | 183,030 |   |
| Commercial | Corporate banking | Term Extension                                                           |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              | (10)           | 13,676      | 22 |   |
| Commercial | Corporate banking | Capitalized                                                              |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 0           |   |   |
| Commercial | Corporate banking | Rate Reduction                                                           |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | (127)       |   |   |
| Commercial | Corporate banking | Principal Forbearance                                                    |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 2              | 1,342          | 13,483      | 27,198 |   |
| Commercial | Corporate banking | Fee Waiver                                                               |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 38          |   |   |
| Commercial | Corporate banking | Other                                                                    |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | $ 125          | $ 2,927        | $ 416       | $ 3,438 |   |
| Commercial | Middle market commercial real estate                                                         |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Number of Contracts | contract                                                                            |           | 1              | 1           | 5 |   |
| Pre-TDR Recorded Investment                                                                               |           | $ 500          | $ 19,979    | $ 11,326 |   |
| Post-TDR Recorded Investment                                                                              |           | $ 15,107       | $ 19,384    | $ 55,809 |   |
| **TDRs which Subsequently Defaulted**                                                                     |           |           |        |   |   |
| Number of Contracts | contract                                                                            | 5              | 0              | 10          | 0 |   |
| Recorded Investment                                                                                       | $ 6,386        | $ 0            | $ 6,825     | $ 0 |   |
| Commercial | Middle market commercial real estate | Term Extension                                        |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              |           | 0              | 595         | 0 |   |
| Commercial | Middle market commercial real estate | Capitalized                                           |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              |           |           | 0           |   |   |
| Commercial | Middle market commercial real estate | Rate Reduction                                        |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              |           |           | 0           |   |   |
| Commercial | Middle market commercial real estate | Principal Forbearance                                 |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              |           | 0              | 0           | 0 |   |
| Commercial | Middle market commercial real estate | Fee Waiver                                            |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              |           |           | 0           |   |   |
| Commercial | Middle market commercial real estate | Other                                                 |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              |           | $ (14,607)     | $ 0         | $ (44,483) |   |
| Commercial | Santander real estate capital                                                                |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Number of Contracts | contract                                                                            |           | 0              |        | 1 |   |
| Pre-TDR Recorded Investment                                                                               |           | $ 0            |        | $ 8,729 |   |
| Post-TDR Recorded Investment                                                                              |           | 0              |        | 8,711 |   |
| Commercial | Santander real estate capital | Term Extension                                               |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              |           | 0              |        | 0 |   |
| Commercial | Santander real estate capital | Principal Forbearance                                        |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              |           | 0              |        | 0 |   |
| Commercial | Santander real estate capital | Other                                                        |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              |           | $ 0            |        | $ 18 |   |
| Commercial | Commercial and industrial                                                                    |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Number of Contracts | contract                                                                            | 252            | 249            | 639         | 815 |   |
| Pre-TDR Recorded Investment                                                                               | $ 3,079        | $ 6,475        | $ 15,486    | $ 26,601 |   |
| Post-TDR Recorded Investment                                                                              | $ 3,045        | $ 6,362        | $ 15,441    | $ 26,522 |   |
| **TDRs which Subsequently Defaulted**                                                                     |           |           |        |   |   |
| Number of Contracts | contract                                                                            | 61             | 76             | 163         | 194 |   |
| Recorded Investment                                                                                       | $ 2,210        | $ 2,838        | $ 5,842     | $ 14,223 |   |
| Commercial | Commercial and industrial | Term Extension                                                   |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 3              | 0              | 10          | 0 |   |
| Commercial | Commercial and industrial | Capitalized                                                      |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 0           |   |   |
| Commercial | Commercial and industrial | Rate Reduction                                                   |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 0           |   |   |
| Commercial | Commercial and industrial | Principal Forbearance                                            |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              | 0              | 0           | 0 |   |
| Commercial | Commercial and industrial | Fee Waiver                                                       |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 0           |   |   |
| Commercial | Commercial and industrial | Other                                                            |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | $ 31           | $ 113          | $ 35        | $ 79 |   |
| Consumer | Residential mortgages                                                                          |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Number of Contracts | contract                                                                            | 38             | 68             | 187         | 237 |   |
| Pre-TDR Recorded Investment                                                                               | $ 7,750        | $ 10,917       | $ 36,724    | $ 36,354 |   |
| Post-TDR Recorded Investment                                                                              | $ 7,338        | $ 10,509       | $ 36,251    | $ 36,350 |   |
| **TDRs which Subsequently Defaulted**                                                                     |           |           |        |   |   |
| Number of Contracts | contract                                                                            | 55             | 5              | 175         | 22 |   |
| Recorded Investment                                                                                       | $ 8,594        | $ 579          | $ 23,659    | $ 3,171 |   |
| Consumer | Residential mortgages | Term Extension                                                         |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              | 0              | (6)         | 1 |   |
| Consumer | Residential mortgages | Capitalized                                                            |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | (357)          |           | (698)       |   |   |
| Consumer | Residential mortgages | Rate Reduction                                                         |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | (133)       |   |   |
| Consumer | Residential mortgages | Principal Forbearance                                                  |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              | 0              | 0           | 0 |   |
| Consumer | Residential mortgages | Fee Waiver                                                             |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 0           |   |   |
| Consumer | Residential mortgages | Other                                                                  |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | $ 769          | $ 408          | $ 1,310     | $ 3 |   |
| Consumer | Home equity loans and lines of credit                                                          |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Number of Contracts | contract                                                                            | 9              | 39             | 45          | 141 |   |
| Pre-TDR Recorded Investment                                                                               | $ 995          | $ 2,637        | $ 3,838     | $ 9,680 |   |
| Post-TDR Recorded Investment                                                                              | $ 966          | $ 2,564        | $ 4,347     | $ 9,454 |   |
| **TDRs which Subsequently Defaulted**                                                                     |           |           |        |   |   |
| Number of Contracts | contract                                                                            | 2              | 19             | 6           | 54 |   |
| Recorded Investment                                                                                       | $ 47           | $ 2,991        | $ 257       | $ 8,457 |   |
| Consumer | Home equity loans and lines of credit | Term Extension                                         |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              | 132            | 0           | 0 |   |
| Consumer | Home equity loans and lines of credit | Capitalized                                            |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 0           |   |   |
| Consumer | Home equity loans and lines of credit | Rate Reduction                                         |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 0           |   |   |
| Consumer | Home equity loans and lines of credit | Principal Forbearance                                  |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              | 0              | 0           | 0 |   |
| Consumer | Home equity loans and lines of credit | Fee Waiver                                             |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 0           |   |   |
| Consumer | Home equity loans and lines of credit | Other                                                  |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | $ 29           | $ (59)         | $ (509)     | $ 226 |   |
| Consumer | Retail installment contracts and auto loans                                                    |           |           |        |   |   |
| **TDRs which Subsequently Defaulted**                                                                     |           |           |        |   |   |
| Number of Contracts | contract                                                                            | 11,275         | 12,112         | 34,496      | 35,299 |   |
| Recorded Investment                                                                                       | $ 199,045      | $ 208,762      | $ 606,327   | $ 588,127 |   |
| Consumer | Retail installment contracts and auto loans, originated                                        |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Number of Contracts | contract                                                                            | 67,044         | 43,632         | 163,797     | 109,896 |   |
| Pre-TDR Recorded Investment                                                                               | $ 1,166,434    | $ 798,710      | $ 2,870,605 | $ 2,023,661 |   |
| Post-TDR Recorded Investment                                                                              | 1,165,271      | 798,469        | 2,867,574   | 2,023,065 |   |
| Consumer | Retail installment contracts and auto loans, originated | Term Extension                       |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 1,228          | 122            | 2,949       | 369 |   |
| Consumer | Retail installment contracts and auto loans, originated | Capitalized                          |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 0           |   |   |
| Consumer | Retail installment contracts and auto loans, originated | Rate Reduction                       |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 0           |   |   |
| Consumer | Retail installment contracts and auto loans, originated | Principal Forbearance                |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              | 0              | 0           | 0 |   |
| Consumer | Retail installment contracts and auto loans, originated | Fee Waiver                           |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 0           |   |   |
| Consumer | Retail installment contracts and auto loans, originated | Other                                |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | $ (65)         | $ 119          | $ 82        | $ 227 |   |
| Consumer | Retail installment contracts and auto loans, purchased                                         |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Number of Contracts | contract                                                                            | 19             | 10,227         | 98          | 35,072 |   |
| Pre-TDR Recorded Investment                                                                               | $ 1,057        | $ 108,855      | $ 1,447     | $ 407,562 |   |
| Post-TDR Recorded Investment                                                                              | 1,063          | 108,176        | 1,445       | 405,700 |   |
| Consumer | Retail installment contracts and auto loans, purchased | Term Extension                        |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | (4)            | 657            | 2           | 1,799 |   |
| Consumer | Retail installment contracts and auto loans, purchased | Capitalized                           |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           |             |   |   |
| Consumer | Retail installment contracts and auto loans, purchased | Rate Reduction                        |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           |             |   |   |
| Consumer | Retail installment contracts and auto loans, purchased | Principal Forbearance                 |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              | 0              | 0           | 0 |   |
| Consumer | Retail installment contracts and auto loans, purchased | Fee Waiver                            |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           |             |   |   |
| Consumer | Retail installment contracts and auto loans, purchased | Other                                 |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | $ (2)          | $ 22           | $ 0         | $ 63 |   |
| Consumer | Personal unsecured loans                                                                       |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Number of Contracts | contract                                                                            | 3,109          | 756            | 10,999      | 18,264 |   |
| Pre-TDR Recorded Investment                                                                               | $ 5,330        | $ 2,014        | $ 18,470    | $ 27,639 |   |
| Post-TDR Recorded Investment                                                                              | $ 5,224        | $ 1,924        | $ 18,251    | $ 27,369 |   |
| **TDRs which Subsequently Defaulted**                                                                     |           |           |        |   |   |
| Number of Contracts | contract                                                                            | 731            | 719            | 2,667       | 3,594 |   |
| Recorded Investment                                                                                       | $ 2,029        | $ 1,676        | $ 6,769     | $ 5,048 |   |
| Consumer | Personal unsecured loans | Term Extension                                                      |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              | 0              | 0           | 0 |   |
| Consumer | Personal unsecured loans | Capitalized                                                         |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 0           |   |   |
| Consumer | Personal unsecured loans | Rate Reduction                                                      |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 0           |   |   |
| Consumer | Personal unsecured loans | Principal Forbearance                                               |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              | 0              | 0           | 0 |   |
| Consumer | Personal unsecured loans | Fee Waiver                                                          |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 0           |   |   |
| Consumer | Personal unsecured loans | Other                                                               |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | $ 106          | $ 90           | $ 219       | $ 270 |   |
| Consumer | Other consumer                                                                                 |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Number of Contracts | contract                                                                            | 35             | 255            | 97          | 285 |   |
| Pre-TDR Recorded Investment                                                                               | $ 581          | $ 5,636        | $ 2,385     | $ 6,726 |   |
| Post-TDR Recorded Investment                                                                              | $ 581          | $ 5,663        | $ 2,385     | $ 6,574 |   |
| **TDRs which Subsequently Defaulted**                                                                     |           |           |        |   |   |
| Number of Contracts | contract                                                                            | 7              | 263            | 29          | 263 |   |
| Recorded Investment                                                                                       | $ 58           | $ 766          | $ 334       | $ 766 |   |
| Consumer | Other consumer | Term Extension                                                                |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              | 2              | 0           | 2 |   |
| Consumer | Other consumer | Capitalized                                                                   |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 1              |           | (1)         |   |   |
| Consumer | Other consumer | Rate Reduction                                                                |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 0           |   |   |
| Consumer | Other consumer | Principal Forbearance                                                         |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              | 0              | 0           | 0 |   |
| Consumer | Other consumer | Fee Waiver                                                                    |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 0              |           | 0           |   |   |
| Consumer | Other consumer | Other                                                                         |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Post-TDR Recorded Investment                                                                              | 1              | $ (29)         | 1           | $ 150 |   |
| Performing                                                                                                |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Troubled debt restructurings                                                                              | 5,959,537      |           | 5,959,537   |   | 5,169,788 |
| Non-performing                                                                                            |           |           |        |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                      |           |           |        |   |   |
| Troubled debt restructurings                                                                              | $ 941,936      |           | $ 941,936   |   | $ 937,127 |

| X                                                                                                                                                                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Financing Receivable, Modifications, Subsequent Default [Abstract]
+ References
No definition available.
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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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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of financing receivables that have been modified by troubled debt restructurings.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Post-modification amount of investment in financing receivables modified by troubled debt restructurings.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524
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