| **Loans and Allowance for Credit Losses - Recorded Investment and Unpaid Principal Balance for Impaired Loans with Associated Allowance (Detail) - USD ($) $ in Thousands** | 3 Months Ended | 6 Months Ended |          |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|----------|
||
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | $ 29,239       |           | $ 29,239 |   | $ 54,167 |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 37,765         |           | 37,765   |   | 63,660 |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 29,690         | $ 30,369       | 30,233   | $ 31,102 |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 138            | 201            | 262      | 300 |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 6,453          |           | 6,453    |   | 1,013 |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 7,263          |           | 7,263    |   | 1,060 |
| Related allowance                                                                                                                                                           | 360            |           | 360      |   | 395 |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 6,510          | 23,120         | 7,024    | 21,543 |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              | 19             | 0        | 36 |   |
| Recorded investment                                                                                                                                                         | 35,692         |           | 35,692   |   | 55,180 |
| Unpaid principal balance                                                                                                                                                    | 45,028         |           | 45,028   |   | 64,720 |
| Impaired Financing Receivable, Average Recorded Investment                                                                                                                  | 36,200         | 53,489         | 37,257   | 52,645 |   |
| Impaired Financing Receivable, Interest Income, Cash Basis Method                                                                                                           | 138            | 220            | 262      | 336 |   |
| Commercial, financial, agricultural and other [Member]                                                                                                                      |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 3,653          |           | 3,653    |   | 3,720 |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 10,002         |           | 10,002   |   | 10,303 |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 3,822          | 5,591          | 3,883    | 3,966 |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 27             | 31             | 50       | 43 |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 0              |           | 0        |   | 327 |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 0              |           | 0        |   | 349 |
| Related allowance                                                                                                                                                           | 0              |           | 0        |   | 307 |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 0              | 8,791          | 0        | 6,813 |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              | 19             | 0        | 36 |   |
| Construction                                                                                                                                                                |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 0              |           | 0        |   | 45 |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 0              |           | 0        |   | 53 |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 0              |           | 0        |   | 0 |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 0              |           | 0        |   | 0 |
| Related allowance                                                                                                                                                           | 0              |           | 0        |   | 0 |
| Residential real estate [Member]                                                                                                                                            |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 8,638          |           | 8,638    |   | 9,365 |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 10,527         |           | 10,527   |   | 11,294 |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 8,769          | 10,560         | 8,985    | 10,726 |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 57             | 159            | 141      | 221 |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 0              |           | 0        |   | 0 |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 0              |           | 0        |   | 0 |
| Related allowance                                                                                                                                                           | 0              |           | 0        |   | 0 |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 0              | 0              | 0        | 0 |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              | 0              | 0        | 0 |   |
| Commercial Real Estate [Member]                                                                                                                                             |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 16,510         |           | 16,510   |   | 40,591 |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 16,752         |           | 16,752   |   | 41,525 |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 16,676         | 13,689         | 16,933   | 15,879 |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 49             | 7              | 63       | 30 |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 6,453          |           | 6,453    |   | 686 |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 7,263          |           | 7,263    |   | 711 |
| Related allowance                                                                                                                                                           | 360            |           | 360      |   | 88 |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 6,510          | 14,329         | 7,024    | 14,730 |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              | 0              | 0        | 0 |   |
| Loans to individuals [Member]                                                                                                                                               |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 438            |           | 438      |   | 446 |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 484            |           | 484      |   | 485 |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 423            | 475            | 432      | 477 |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 5              | 4              | 8        | 6 |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 0              |           | 0        |   | 0 |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 0              |           | 0        |   | 0 |
| Related allowance                                                                                                                                                           | 0              |           | 0        |   | 0 |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 0              | 0              | 0        | 0 |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              | 0              | 0        | 0 |   |
| Real estate construction [Member]                                                                                                                                           |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 0              | 54             | 0        | 54 |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 0              | 0              | 0        | 0 |   |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 0              | 0              | 0        | 0 |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              | 0              | 0        | 0 |   |
| Time and Demand Loans | Commercial, financial, agricultural and other [Member]                                                                                              |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 3,653          |           | 3,653    |   | 3,720 |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 10,002         |           | 10,002   |   | 10,303 |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 3,822          | 5,591          | 3,883    | 3,966 |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 27             | 31             | 50       | 43 |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 0              |           | 0        |   | 327 |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 0              |           | 0        |   | 349 |
| Related allowance                                                                                                                                                           | 0              |           | 0        |   | 307 |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 0              | 8,791          | 0        | 6,813 |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              | 19             | 0        | 36 |   |
| Senior Lien | Residential real estate [Member]                                                                                                                              |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 4,859          |           | 4,859    |   | 5,200 |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 5,950          |           | 5,950    |   | 6,337 |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 4,963          | 5,661          | 5,080    | 5,822 |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 43             | 132            | 105      | 176 |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 0              |           | 0        |   | 0 |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 0              |           | 0        |   | 0 |
| Related allowance                                                                                                                                                           | 0              |           | 0        |   | 0 |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 0              | 0              | 0        | 0 |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              | 0              | 0        | 0 |   |
| Junior Lien | Residential real estate [Member]                                                                                                                              |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 3,779          |           | 3,779    |   | 4,165 |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 4,577          |           | 4,577    |   | 4,957 |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 3,806          | 4,899          | 3,905    | 4,904 |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 14             | 27             | 36       | 45 |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 0              |           | 0        |   | 0 |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 0              |           | 0        |   | 0 |
| Related allowance                                                                                                                                                           | 0              |           | 0        |   | 0 |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 0              | 0              | 0        | 0 |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              | 0              | 0        | 0 |   |
| Multifamily | Commercial Real Estate [Member]                                                                                                                               |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 0              |           | 0        |   | 14,677 |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 0              |           | 0        |   | 14,677 |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 273            | 0              | 344      | 0 |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 0              | 0              | 0        | 0 |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 0              |           | 0        |   | 421 |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 0              |           | 0        |   | 446 |
| Related allowance                                                                                                                                                           | 0              |           | 0        |   | 88 |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 0              | 450            | 0        | 457 |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              | 0              | 0        | 0 |   |
| Nonowner Occupied Commercial Real Estate | Commercial Real Estate [Member]                                                                                                  |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 14,913         |           | 14,913   |   | 24,581 |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 14,939         |           | 14,939   |   | 25,310 |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 14,796         | 11,227         | 14,986   | 13,079 |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 42             | 2              | 52       | 10 |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 6,453          |           | 6,453    |   | 0 |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 7,263          |           | 7,263    |   | 0 |
| Related allowance                                                                                                                                                           | 360            |           | 360      |   | 0 |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 6,510          | 13,614         | 7,024    | 14,096 |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              | 0              | 0        | 0 |   |
| Owner Occupied Commercial Real Estate | Commercial Real Estate [Member]                                                                                                     |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 1,597          |           | 1,597    |   | 1,333 |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 1,813          |           | 1,813    |   | 1,538 |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 1,607          | 2,462          | 1,603    | 2,800 |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 7              | 5              | 11       | 20 |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 0              |           | 0        |   | 265 |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 0              |           | 0        |   | 265 |
| Related allowance                                                                                                                                                           | 0              |           | 0        |   | 0 |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 0              | 265            | 0        | 177 |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              | 0              | 0        | 0 |   |
| Automobiles | Loans to individuals [Member]                                                                                                                                 |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 364            |           | 364      |   | 388 |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 405            |           | 405      |   | 422 |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 365            | 415            | 361      | 426 |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 5              | 4              | 8        | 6 |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 0              |           | 0        |   | 0 |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 0              |           | 0        |   | 0 |
| Related allowance                                                                                                                                                           | 0              |           | 0        |   | 0 |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 0              | 0              | 0        | 0 |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              | 0              | 0        | 0 |   |
| Other Consumer Loans | Loans to individuals [Member]                                                                                                                        |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 74             |           | 74       |   | 58 |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 79             |           | 79       |   | 63 |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 58             | 60             | 71       | 51 |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 0              | 0              | 0        | 0 |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 0              |           | 0        |   | 0 |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 0              |           | 0        |   | 0 |
| Related allowance                                                                                                                                                           | 0              |           | 0        |   | $ 0 |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 0              | 0              | 0        | 0 |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              | $ 0            | 0        | $ 0 |   |
| Construction Residential | Construction                                                                                                                                     |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 0              |           | 0        |   |   |
| Related allowance                                                                                                                                                           | 0              |           | 0        |   |   |
| Construction Residential | Real estate construction [Member]                                                                                                                |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              |           | 0        |   |   |
| Construction Other | Construction                                                                                                                                           |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 0              |           | 0        |   |   |
| Related allowance                                                                                                                                                           | 0              |           | 0        |   |   |
| Construction Other | Real estate construction [Member]                                                                                                                      |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              |           | 0        |   |   |
| Time and Demand Loans Other | Commercial, financial, agricultural and other [Member]                                                                                        |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 0              |           | 0        |   |   |
| Related allowance                                                                                                                                                           | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | 0              |           | 0        |   |   |
| Equipment Finance | Commercial, financial, agricultural and other [Member]                                                                                                  |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                                             |           |           |     |   |   |
| Impaired Financing Receivable, with No Related Allowance, Recorded Investment                                                                                               | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance                                                                                          | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment                                                                                       | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method                                                                                | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with Related Allowance, Recorded Investment                                                                                                  | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance                                                                                             | 0              |           | 0        |   |   |
| Related allowance                                                                                                                                                           | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with Related Allowance, Average Recorded Investment                                                                                          | 0              |           | 0        |   |   |
| Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method                                                                                   | $ 0            |           | $ 0      |   |   |

| X                                                                                                                                                                                                                                                                                                                                                                                                                            |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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.
+ Details**Name:**us-gaap_FinancingReceivableImpairedLineItems**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.
+ References
Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(1) -URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524
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