| **NON-INTEREST INCOME AND OTHER EXPENSES (Disaggregation by Revenue Source) (Details) - USD ($) $ in Thousands** | 3 Months Ended | 9 Months Ended |
|------------------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Disaggregation of Revenue [Line Items]**                                                                       |           |           |   |   |
| Lease income                                                                                                     | $ 742,946      | $ 735,783      | $ 2,269,613 | $ 2,116,503 |
| Miscellaneous income/(loss)                                                                                      | 177,362        | 11,636         | (92,511) | (26,620) |
| Net gain/(loss) on sale of investment securities                                                                 | (148)          | 2,267          | 31,646 | 2,646 |
| Total out-of-scope of revenue from contracts with customers                                                      | 985,020        | 809,118        | 2,386,996 | 2,293,501 |
| Non-interest income                                                                                              | 1,174,854      | 1,001,132      | 2,988,331 | 2,859,564 |
| Total in-scope of revenue from contracts with customers                                                          |           |           |   |   |
| **Disaggregation of Revenue [Line Items]**                                                                       |           |           |   |   |
| In-scope of revenue from contracts with customers                                                                | 189,834        | 192,014        | 601,335 | 566,063 |
| Depository services                                                                                              |           |           |   |   |
| **Disaggregation of Revenue [Line Items]**                                                                       |           |           |   |   |
| In-scope of revenue from contracts with customers                                                                | 45,674         | 63,016         | 144,703 | 179,298 |
| Commission and trailer fees                                                                                      |           |           |   |   |
| **Disaggregation of Revenue [Line Items]**                                                                       |           |           |   |   |
| In-scope of revenue from contracts with customers                                                                | 47,466         | 39,971         | 144,730 | 119,607 |
| Interchange income, net                                                                                          |           |           |   |   |
| **Disaggregation of Revenue [Line Items]**                                                                       |           |           |   |   |
| In-scope of revenue from contracts with customers                                                                | 15,648         | 16,891         | 47,567 | 49,854 |
| Underwriting service fees                                                                                        |           |           |   |   |
| **Disaggregation of Revenue [Line Items]**                                                                       |           |           |   |   |
| In-scope of revenue from contracts with customers                                                                | 35,186         | 27,043         | 110,593 | 77,835 |
| Asset and wealth management fees                                                                                 |           |           |   |   |
| **Disaggregation of Revenue [Line Items]**                                                                       |           |           |   |   |
| In-scope of revenue from contracts with customers                                                                | 32,283         | 35,169         | 101,574 | 109,166 |
| Other revenue from contracts with customers                                                                      |           |           |   |   |
| **Disaggregation of Revenue [Line Items]**                                                                       |           |           |   |   |
| In-scope of revenue from contracts with customers                                                                | 13,577         | 9,924          | 52,168 | 30,303 |
| Consumer and commercial fees                                                                                     |           |           |   |   |
| **Disaggregation of Revenue [Line Items]**                                                                       |           |           |   |   |
| Out-of-scope of revenue from contracts with customers                                                            | $ 64,860       | $ 59,432       | $ 178,248 | $ 200,972 |

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Miscellaneous Income (Loss)
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Amount of realized gain (loss) on investment in debt and equity securities.
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Amount of lease income from operating, direct financing, and sales-type leases. Includes, but is not limited to, variable lease payments, interest income, profit (loss) recognized at commencement, and lease payments paid and payable to lessor.
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The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.
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Amount of revenue earned, classified as other, excluding interest income.
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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.
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