| **LOANS AND ALLOWANCE - Risk Grading of Loan Portfolio by Loan Class (Details) - USD ($) $ in Thousands** | 9 Months Ended |             |
|-----------------------------------------------------------------------------------------------------------|----------------|-------------|
||
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | $ 2,212,810    | $ 3,483,295 |
| Fiscal year before current fiscal year                                                                    | 2,705,962      | 2,680,834   |
| Two years before current fiscal year                                                                      | 2,210,224      | 1,843,080   |
| Three years before current fiscal year                                                                    | 1,500,790      | 686,065     |
| Four years before current fiscal year                                                                     | 553,043        | 385,461     |
| Prior                                                                                                     | 958,254        | 828,159     |
| Revolving loans amortized cost basis                                                                      | 2,126,807      | 2,084,096   |
| Revolving loans converted to term                                                                         | 3,532          | 12,904      |
| Total                                                                                                     | 12,271,422     | 12,003,894  |
| Commercial and industrial loans                                                                           |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 918,136        | 1,094,363   |
| Current fiscal year, writeoff                                                                             | 13,901         |        |
| Fiscal year before current fiscal year                                                                    | 584,258        | 576,080     |
| Fiscal year before current fiscal year, writeoff                                                          | 508            |        |
| Two years before current fiscal year                                                                      | 319,453        | 159,416     |
| Two years before current fiscal year, writeoff                                                            | 400            |        |
| Three years before current fiscal year                                                                    | 105,004        | 131,332     |
| Three years before current fiscal year, writeoff                                                          | 5,588          |        |
| Four years before current fiscal year                                                                     | 58,313         | 48,822      |
| Four years before current fiscal year, writeoff                                                           | 76             |        |
| Prior                                                                                                     | 51,646         | 48,058      |
| Prior, writeoff                                                                                           | 239            |        |
| Revolving loans amortized cost basis                                                                      | 1,454,093      | 1,373,714   |
| Revolving loans amortized cost basis, writeoff                                                            | 0              |        |
| Revolving loans converted to term                                                                         | 50             | 5,341       |
| Revolving loans converted to term, writeoff                                                               | 0              |        |
| Total                                                                                                     | 3,490,953      | 3,437,126   |
| Total, writeoff                                                                                           | 20,712         |        |
| Commercial and industrial loans | Pass                                                                    |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 901,876        | 1,064,687   |
| Fiscal year before current fiscal year                                                                    | 548,276        | 531,504     |
| Two years before current fiscal year                                                                      | 296,471        | 141,985     |
| Three years before current fiscal year                                                                    | 95,426         | 114,999     |
| Four years before current fiscal year                                                                     | 53,498         | 43,136      |
| Prior                                                                                                     | 49,094         | 45,310      |
| Revolving loans amortized cost basis                                                                      | 1,374,146      | 1,302,562   |
| Revolving loans converted to term                                                                         | 50             | 5,048       |
| Total                                                                                                     | 3,318,837      | 3,249,231   |
| Commercial and industrial loans | Special Mention                                                         |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 9,450          | 2,164       |
| Fiscal year before current fiscal year                                                                    | 11,955         | 18,005      |
| Two years before current fiscal year                                                                      | 6,428          | 11,900      |
| Three years before current fiscal year                                                                    | 5,470          | 5,727       |
| Four years before current fiscal year                                                                     | 114            | 1,012       |
| Prior                                                                                                     | 897            | 2,181       |
| Revolving loans amortized cost basis                                                                      | 28,202         | 27,702      |
| Revolving loans converted to term                                                                         | 0              | 150         |
| Total                                                                                                     | 62,516         | 68,841      |
| Commercial and industrial loans | Substandard                                                             |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 5,902          | 27,512      |
| Fiscal year before current fiscal year                                                                    | 20,082         | 26,571      |
| Two years before current fiscal year                                                                      | 16,554         | 5,531       |
| Three years before current fiscal year                                                                    | 1,959          | 10,606      |
| Four years before current fiscal year                                                                     | 4,701          | 4,674       |
| Prior                                                                                                     | 1,655          | 567         |
| Revolving loans amortized cost basis                                                                      | 48,890         | 43,450      |
| Revolving loans converted to term                                                                         | 0              | 143         |
| Total                                                                                                     | 99,743         | 119,054     |
| Commercial and industrial loans | Doubtful                                                                |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 908            |        |
| Fiscal year before current fiscal year                                                                    | 3,945          |        |
| Two years before current fiscal year                                                                      | 0              |        |
| Three years before current fiscal year                                                                    | 2,149          |        |
| Four years before current fiscal year                                                                     | 0              |        |
| Prior                                                                                                     | 0              |        |
| Revolving loans amortized cost basis                                                                      | 2,855          |        |
| Revolving loans converted to term                                                                         | 0              |        |
| Total                                                                                                     | 9,857          |        |
| Agricultural land, production and other loans to farmers                                                  |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 22,555         | 44,910      |
| Current fiscal year, writeoff                                                                             | 0              |        |
| Fiscal year before current fiscal year                                                                    | 39,288         | 37,083      |
| Fiscal year before current fiscal year, writeoff                                                          | 0              |        |
| Two years before current fiscal year                                                                      | 33,059         | 36,281      |
| Two years before current fiscal year, writeoff                                                            | 0              |        |
| Three years before current fiscal year                                                                    | 32,692         | 15,296      |
| Three years before current fiscal year, writeoff                                                          | 0              |        |
| Four years before current fiscal year                                                                     | 13,819         | 4,127       |
| Four years before current fiscal year, writeoff                                                           | 0              |        |
| Prior                                                                                                     | 26,912         | 30,694      |
| Prior, writeoff                                                                                           | 0              |        |
| Revolving loans amortized cost basis                                                                      | 65,513         | 73,402      |
| Revolving loans amortized cost basis, writeoff                                                            | 0              |        |
| Revolving loans converted to term                                                                         | 0              | 0           |
| Revolving loans converted to term, writeoff                                                               | 0              |        |
| Total                                                                                                     | 233,838        | 241,793     |
| Total, writeoff                                                                                           | 0              |        |
| Agricultural land, production and other loans to farmers | Pass                                           |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 22,521         | 44,446      |
| Fiscal year before current fiscal year                                                                    | 38,866         | 36,299      |
| Two years before current fiscal year                                                                      | 33,059         | 35,791      |
| Three years before current fiscal year                                                                    | 32,234         | 15,296      |
| Four years before current fiscal year                                                                     | 13,819         | 3,752       |
| Prior                                                                                                     | 26,251         | 28,910      |
| Revolving loans amortized cost basis                                                                      | 65,513         | 73,402      |
| Revolving loans converted to term                                                                         | 0              | 0           |
| Total                                                                                                     | 232,263        | 237,896     |
| Agricultural land, production and other loans to farmers | Special Mention                                |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 0              | 286         |
| Fiscal year before current fiscal year                                                                    | 266            | 784         |
| Two years before current fiscal year                                                                      | 0              | 0           |
| Three years before current fiscal year                                                                    | 0              | 0           |
| Four years before current fiscal year                                                                     | 0              | 281         |
| Prior                                                                                                     | 597            | 632         |
| Revolving loans amortized cost basis                                                                      | 0              | 0           |
| Revolving loans converted to term                                                                         | 0              | 0           |
| Total                                                                                                     | 863            | 1,983       |
| Agricultural land, production and other loans to farmers | Substandard                                    |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 34             | 178         |
| Fiscal year before current fiscal year                                                                    | 156            | 0           |
| Two years before current fiscal year                                                                      | 0              | 490         |
| Three years before current fiscal year                                                                    | 458            | 0           |
| Four years before current fiscal year                                                                     | 0              | 94          |
| Prior                                                                                                     | 64             | 1,152       |
| Revolving loans amortized cost basis                                                                      | 0              | 0           |
| Revolving loans converted to term                                                                         | 0              | 0           |
| Total                                                                                                     | 712            | 1,914       |
| Construction                                                                                              |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 397,654        | 383,367     |
| Current fiscal year, writeoff                                                                             | 0              |        |
| Fiscal year before current fiscal year                                                                    | 299,869        | 301,986     |
| Fiscal year before current fiscal year, writeoff                                                          | 0              |        |
| Two years before current fiscal year                                                                      | 271,417        | 117,541     |
| Two years before current fiscal year, writeoff                                                            | 0              |        |
| Three years before current fiscal year                                                                    | 35,171         | 11,428      |
| Three years before current fiscal year, writeoff                                                          | 0              |        |
| Four years before current fiscal year                                                                     | 4,047          | 857         |
| Four years before current fiscal year, writeoff                                                           | 0              |        |
| Prior                                                                                                     | 2,526          | 3,236       |
| Prior, writeoff                                                                                           | 0              |        |
| Revolving loans amortized cost basis                                                                      | 11,577         | 17,167      |
| Revolving loans amortized cost basis, writeoff                                                            | 0              |        |
| Revolving loans converted to term                                                                         | 0              | 0           |
| Revolving loans converted to term, writeoff                                                               | 0              |        |
| Total                                                                                                     | 1,022,261      | 835,582     |
| Total, writeoff                                                                                           | 0              |        |
| Construction | Pass                                                                                       |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 362,578        | 366,414     |
| Fiscal year before current fiscal year                                                                    | 295,563        | 301,986     |
| Two years before current fiscal year                                                                      | 266,129        | 117,541     |
| Three years before current fiscal year                                                                    | 14,325         | 11,428      |
| Four years before current fiscal year                                                                     | 4,047          | 857         |
| Prior                                                                                                     | 2,526          | 3,224       |
| Revolving loans amortized cost basis                                                                      | 11,577         | 17,167      |
| Revolving loans converted to term                                                                         | 0              | 0           |
| Total                                                                                                     | 956,745        | 818,617     |
| Construction | Special Mention                                                                            |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 35,063         | 16,922      |
| Fiscal year before current fiscal year                                                                    | 424            | 0           |
| Two years before current fiscal year                                                                      | 0              | 0           |
| Three years before current fiscal year                                                                    | 20,846         | 0           |
| Four years before current fiscal year                                                                     | 0              | 0           |
| Prior                                                                                                     | 0              | 0           |
| Revolving loans amortized cost basis                                                                      | 0              | 0           |
| Revolving loans converted to term                                                                         | 0              | 0           |
| Total                                                                                                     | 56,333         | 16,922      |
| Construction | Substandard                                                                                |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 13             | 31          |
| Fiscal year before current fiscal year                                                                    | 3,882          | 0           |
| Two years before current fiscal year                                                                      | 5,288          | 0           |
| Three years before current fiscal year                                                                    | 0              | 0           |
| Four years before current fiscal year                                                                     | 0              | 0           |
| Prior                                                                                                     | 0              | 12          |
| Revolving loans amortized cost basis                                                                      | 0              | 0           |
| Revolving loans converted to term                                                                         | 0              | 0           |
| Total                                                                                                     | 9,183          | 43          |
| Commercial real estate, non-owner occupied                                                                |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 298,116        | 630,708     |
| Current fiscal year, writeoff                                                                             | 0              |        |
| Fiscal year before current fiscal year                                                                    | 562,124        | 615,408     |
| Fiscal year before current fiscal year, writeoff                                                          | 2              |        |
| Two years before current fiscal year                                                                      | 541,141        | 596,899     |
| Two years before current fiscal year, writeoff                                                            | 0              |        |
| Three years before current fiscal year                                                                    | 497,135        | 187,486     |
| Three years before current fiscal year, writeoff                                                          | 0              |        |
| Four years before current fiscal year                                                                     | 169,203        | 132,847     |
| Four years before current fiscal year, writeoff                                                           | 0              |        |
| Prior                                                                                                     | 260,968        | 209,128     |
| Prior, writeoff                                                                                           | 0              |        |
| Revolving loans amortized cost basis                                                                      | 31,909         | 31,196      |
| Revolving loans amortized cost basis, writeoff                                                            | 0              |        |
| Revolving loans converted to term                                                                         | 0              | 3,803       |
| Revolving loans converted to term, writeoff                                                               | 0              |        |
| Total                                                                                                     | 2,360,596      | 2,407,475   |
| Total, writeoff                                                                                           | 2              |        |
| Commercial real estate, non-owner occupied | Pass                                                         |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 214,579        | 560,146     |
| Fiscal year before current fiscal year                                                                    | 529,237        | 603,254     |
| Two years before current fiscal year                                                                      | 533,207        | 550,605     |
| Three years before current fiscal year                                                                    | 471,278        | 168,701     |
| Four years before current fiscal year                                                                     | 142,636        | 116,859     |
| Prior                                                                                                     | 225,787        | 190,264     |
| Revolving loans amortized cost basis                                                                      | 31,615         | 31,196      |
| Revolving loans converted to term                                                                         | 0              | 3,803       |
| Total                                                                                                     | 2,148,339      | 2,224,828   |
| Commercial real estate, non-owner occupied | Special Mention                                              |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 64,871         | 49,439      |
| Fiscal year before current fiscal year                                                                    | 22,956         | 4,026       |
| Two years before current fiscal year                                                                      | 7,842          | 38,268      |
| Three years before current fiscal year                                                                    | 3,641          | 18,785      |
| Four years before current fiscal year                                                                     | 26,567         | 11,546      |
| Prior                                                                                                     | 32,842         | 17,992      |
| Revolving loans amortized cost basis                                                                      | 47             | 0           |
| Revolving loans converted to term                                                                         | 0              | 0           |
| Total                                                                                                     | 158,766        | 140,056     |
| Commercial real estate, non-owner occupied | Substandard                                                  |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 18,666         | 21,123      |
| Fiscal year before current fiscal year                                                                    | 9,807          | 8,128       |
| Two years before current fiscal year                                                                      | 92             | 8,026       |
| Three years before current fiscal year                                                                    | 22,216         | 0           |
| Four years before current fiscal year                                                                     | 0              | 4,442       |
| Prior                                                                                                     | 2,339          | 872         |
| Revolving loans amortized cost basis                                                                      | 247            | 0           |
| Revolving loans converted to term                                                                         | 0              | 0           |
| Total                                                                                                     | 53,367         | 42,591      |
| Commercial real estate, non-owner occupied | Doubtful                                                     |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 0              |        |
| Fiscal year before current fiscal year                                                                    | 124            |        |
| Two years before current fiscal year                                                                      | 0              |        |
| Three years before current fiscal year                                                                    | 0              |        |
| Four years before current fiscal year                                                                     | 0              |        |
| Prior                                                                                                     | 0              |        |
| Revolving loans amortized cost basis                                                                      | 0              |        |
| Revolving loans converted to term                                                                         | 0              |        |
| Total                                                                                                     | 124            |        |
| Commercial real estate, owner occupied                                                                    |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 139,503        | 271,593     |
| Current fiscal year, writeoff                                                                             | 0              |        |
| Fiscal year before current fiscal year                                                                    | 222,019        | 324,004     |
| Fiscal year before current fiscal year, writeoff                                                          | 0              |        |
| Two years before current fiscal year                                                                      | 283,816        | 335,062     |
| Two years before current fiscal year, writeoff                                                            | 0              |        |
| Three years before current fiscal year                                                                    | 277,729        | 119,104     |
| Three years before current fiscal year, writeoff                                                          | 0              |        |
| Four years before current fiscal year                                                                     | 104,394        | 67,946      |
| Four years before current fiscal year, writeoff                                                           | 2              |        |
| Prior                                                                                                     | 97,958         | 90,990      |
| Prior, writeoff                                                                                           | 0              |        |
| Revolving loans amortized cost basis                                                                      | 28,288         | 34,451      |
| Revolving loans amortized cost basis, writeoff                                                            | 0              |        |
| Revolving loans converted to term                                                                         | 0              | 3,378       |
| Revolving loans converted to term, writeoff                                                               | 0              |        |
| Total                                                                                                     | 1,153,707      | 1,246,528   |
| Total, writeoff                                                                                           | 2              |        |
| Commercial real estate, owner occupied | Pass                                                             |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 119,212        | 260,725     |
| Fiscal year before current fiscal year                                                                    | 207,077        | 316,665     |
| Two years before current fiscal year                                                                      | 270,151        | 330,441     |
| Three years before current fiscal year                                                                    | 269,190        | 114,015     |
| Four years before current fiscal year                                                                     | 101,546        | 63,816      |
| Prior                                                                                                     | 87,685         | 81,286      |
| Revolving loans amortized cost basis                                                                      | 27,327         | 33,123      |
| Revolving loans converted to term                                                                         | 0              | 3,378       |
| Total                                                                                                     | 1,082,188      | 1,203,449   |
| Commercial real estate, owner occupied | Special Mention                                                  |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 5,178          | 7,744       |
| Fiscal year before current fiscal year                                                                    | 13,603         | 6,125       |
| Two years before current fiscal year                                                                      | 9,437          | 2,245       |
| Three years before current fiscal year                                                                    | 6,053          | 3,481       |
| Four years before current fiscal year                                                                     | 2,831          | 1,210       |
| Prior                                                                                                     | 5,110          | 2,984       |
| Revolving loans amortized cost basis                                                                      | 334            | 1,328       |
| Revolving loans converted to term                                                                         | 0              | 0           |
| Total                                                                                                     | 42,546         | 25,117      |
| Commercial real estate, owner occupied | Substandard                                                      |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 15,113         | 3,124       |
| Fiscal year before current fiscal year                                                                    | 1,339          | 1,214       |
| Two years before current fiscal year                                                                      | 4,228          | 2,376       |
| Three years before current fiscal year                                                                    | 2,486          | 1,608       |
| Four years before current fiscal year                                                                     | 17             | 2,920       |
| Prior                                                                                                     | 5,163          | 6,720       |
| Revolving loans amortized cost basis                                                                      | 627            | 0           |
| Revolving loans converted to term                                                                         | 0              | 0           |
| Total                                                                                                     | 28,973         | 17,962      |
| Residential                                                                                               |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 333,654        | 762,399     |
| Current fiscal year, writeoff                                                                             | 0              |        |
| Fiscal year before current fiscal year                                                                    | 700,583        | 494,049     |
| Fiscal year before current fiscal year, writeoff                                                          | 42             |        |
| Two years before current fiscal year                                                                      | 458,098        | 405,136     |
| Two years before current fiscal year, writeoff                                                            | 135            |        |
| Three years before current fiscal year                                                                    | 374,931        | 115,738     |
| Three years before current fiscal year, writeoff                                                          | 3              |        |
| Four years before current fiscal year                                                                     | 107,654        | 79,632      |
| Four years before current fiscal year, writeoff                                                           | 0              |        |
| Prior                                                                                                     | 274,903        | 234,141     |
| Prior, writeoff                                                                                           | 63             |        |
| Revolving loans amortized cost basis                                                                      | 7,497          | 5,459       |
| Revolving loans amortized cost basis, writeoff                                                            | 0              |        |
| Revolving loans converted to term                                                                         | 65             | 101         |
| Revolving loans converted to term, writeoff                                                               | 0              |        |
| Total                                                                                                     | 2,257,385      | 2,096,655   |
| Total, writeoff                                                                                           | 243            |        |
| Residential | Pass                                                                                        |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 332,210        | 758,161     |
| Fiscal year before current fiscal year                                                                    | 691,941        | 489,301     |
| Two years before current fiscal year                                                                      | 451,830        | 401,353     |
| Three years before current fiscal year                                                                    | 372,247        | 114,420     |
| Four years before current fiscal year                                                                     | 105,548        | 77,768      |
| Prior                                                                                                     | 265,879        | 229,812     |
| Revolving loans amortized cost basis                                                                      | 4,878          | 5,365       |
| Revolving loans converted to term                                                                         | 65             | 46          |
| Total                                                                                                     | 2,224,598      | 2,076,226   |
| Residential | Special Mention                                                                             |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 1,087          | 2,839       |
| Fiscal year before current fiscal year                                                                    | 5,304          | 2,924       |
| Two years before current fiscal year                                                                      | 4,034          | 1,972       |
| Three years before current fiscal year                                                                    | 1,710          | 513         |
| Four years before current fiscal year                                                                     | 1,578          | 396         |
| Prior                                                                                                     | 6,501          | 2,588       |
| Revolving loans amortized cost basis                                                                      | 2,588          | 34          |
| Revolving loans converted to term                                                                         | 0              | 0           |
| Total                                                                                                     | 22,802         | 11,266      |
| Residential | Substandard                                                                                 |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 357            | 1,399       |
| Fiscal year before current fiscal year                                                                    | 3,338          | 1,824       |
| Two years before current fiscal year                                                                      | 2,234          | 1,811       |
| Three years before current fiscal year                                                                    | 974            | 805         |
| Four years before current fiscal year                                                                     | 528            | 1,468       |
| Prior                                                                                                     | 2,523          | 1,741       |
| Revolving loans amortized cost basis                                                                      | 31             | 60          |
| Revolving loans converted to term                                                                         | 0              | 55          |
| Total                                                                                                     | 9,985          | 9,163       |
| Home equity                                                                                               |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 9,338          | 40,768      |
| Current fiscal year, writeoff                                                                             | 0              |        |
| Fiscal year before current fiscal year                                                                    | 35,504         | 75,749      |
| Fiscal year before current fiscal year, writeoff                                                          | 160            |        |
| Two years before current fiscal year                                                                      | 65,078         | 14,621      |
| Two years before current fiscal year, writeoff                                                            | 182            |        |
| Three years before current fiscal year                                                                    | 12,625         | 1,572       |
| Three years before current fiscal year, writeoff                                                          | 149            |        |
| Four years before current fiscal year                                                                     | 1,162          | 1,528       |
| Four years before current fiscal year, writeoff                                                           | 193            |        |
| Prior                                                                                                     | 4,827          | 3,393       |
| Prior, writeoff                                                                                           | 1,422          |        |
| Revolving loans amortized cost basis                                                                      | 477,999        | 492,720     |
| Revolving loans amortized cost basis, writeoff                                                            | 0              |        |
| Revolving loans converted to term                                                                         | 2,819          | 281         |
| Revolving loans converted to term, writeoff                                                               | 0              |        |
| Total                                                                                                     | 609,352        | 630,632     |
| Total, writeoff                                                                                           | 2,106          |        |
| Home equity | Pass                                                                                        |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 9,155          | 40,768      |
| Fiscal year before current fiscal year                                                                    | 34,784         | 75,670      |
| Two years before current fiscal year                                                                      | 64,438         | 14,621      |
| Three years before current fiscal year                                                                    | 11,511         | 1,572       |
| Four years before current fiscal year                                                                     | 1,162          | 1,348       |
| Prior                                                                                                     | 4,566          | 3,325       |
| Revolving loans amortized cost basis                                                                      | 472,517        | 486,924     |
| Revolving loans converted to term                                                                         | 2,065          | 281         |
| Total                                                                                                     | 600,198        | 624,509     |
| Home equity | Special Mention                                                                             |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 120            | 0           |
| Fiscal year before current fiscal year                                                                    | 720            | 0           |
| Two years before current fiscal year                                                                      | 41             | 0           |
| Three years before current fiscal year                                                                    | 1,114          | 0           |
| Four years before current fiscal year                                                                     | 0              | 115         |
| Prior                                                                                                     | 168            | 8           |
| Revolving loans amortized cost basis                                                                      | 4,108          | 3,698       |
| Revolving loans converted to term                                                                         | 371            | 0           |
| Total                                                                                                     | 6,642          | 3,821       |
| Home equity | Substandard                                                                                 |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 63             | 0           |
| Fiscal year before current fiscal year                                                                    | 0              | 79          |
| Two years before current fiscal year                                                                      | 599            | 0           |
| Three years before current fiscal year                                                                    | 0              | 0           |
| Four years before current fiscal year                                                                     | 0              | 65          |
| Prior                                                                                                     | 93             | 60          |
| Revolving loans amortized cost basis                                                                      | 1,374          | 2,098       |
| Revolving loans converted to term                                                                         | 383            | 0           |
| Total                                                                                                     | 2,512          | 2,302       |
| Individuals' loans for household and other personal expenditures                                          |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 32,619         | 68,062      |
| Current fiscal year, writeoff                                                                             | 98             |        |
| Fiscal year before current fiscal year                                                                    | 53,248         | 43,773      |
| Fiscal year before current fiscal year, writeoff                                                          | 591            |        |
| Two years before current fiscal year                                                                      | 31,525         | 13,105      |
| Two years before current fiscal year, writeoff                                                            | 291            |        |
| Three years before current fiscal year                                                                    | 8,104          | 5,422       |
| Three years before current fiscal year, writeoff                                                          | 77             |        |
| Four years before current fiscal year                                                                     | 2,746          | 5,942       |
| Four years before current fiscal year, writeoff                                                           | 57             |        |
| Prior                                                                                                     | 6,583          | 3,800       |
| Prior, writeoff                                                                                           | 151            |        |
| Revolving loans amortized cost basis                                                                      | 41,100         | 35,107      |
| Revolving loans amortized cost basis, writeoff                                                            | 0              |        |
| Revolving loans converted to term                                                                         | 598            | 0           |
| Revolving loans converted to term, writeoff                                                               | 0              |        |
| Total                                                                                                     | 176,523        | 175,211     |
| Total, writeoff                                                                                           | 1,265          |        |
| Individuals' loans for household and other personal expenditures | Pass                                   |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 32,590         | 67,883      |
| Fiscal year before current fiscal year                                                                    | 52,860         | 43,639      |
| Two years before current fiscal year                                                                      | 31,275         | 13,025      |
| Three years before current fiscal year                                                                    | 8,070          | 5,389       |
| Four years before current fiscal year                                                                     | 2,735          | 5,830       |
| Prior                                                                                                     | 6,572          | 3,775       |
| Revolving loans amortized cost basis                                                                      | 40,907         | 35,091      |
| Revolving loans converted to term                                                                         | 597            | 0           |
| Total                                                                                                     | 175,606        | 174,632     |
| Individuals' loans for household and other personal expenditures | Special Mention                        |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 29             | 178         |
| Fiscal year before current fiscal year                                                                    | 388            | 134         |
| Two years before current fiscal year                                                                      | 250            | 77          |
| Three years before current fiscal year                                                                    | 34             | 33          |
| Four years before current fiscal year                                                                     | 11             | 28          |
| Prior                                                                                                     | 11             | 17          |
| Revolving loans amortized cost basis                                                                      | 193            | 16          |
| Revolving loans converted to term                                                                         | 1              | 0           |
| Total                                                                                                     | 917            | 483         |
| Individuals' loans for household and other personal expenditures | Substandard                            |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 0              | 1           |
| Fiscal year before current fiscal year                                                                    | 0              | 0           |
| Two years before current fiscal year                                                                      | 0              | 3           |
| Three years before current fiscal year                                                                    | 0              | 0           |
| Four years before current fiscal year                                                                     | 0              | 84          |
| Prior                                                                                                     | 0              | 8           |
| Revolving loans amortized cost basis                                                                      | 0              | 0           |
| Revolving loans converted to term                                                                         | 0              | 0           |
| Total                                                                                                     | 0              | 96          |
| Public finance and other commercial loans                                                                 |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 61,235         | 187,125     |
| Current fiscal year, writeoff                                                                             | 13,999         |        |
| Fiscal year before current fiscal year                                                                    | 209,069        | 212,702     |
| Fiscal year before current fiscal year, writeoff                                                          | 1,303          |        |
| Two years before current fiscal year                                                                      | 206,637        | 165,019     |
| Two years before current fiscal year, writeoff                                                            | 1,008          |        |
| Three years before current fiscal year                                                                    | 157,399        | 98,687      |
| Three years before current fiscal year, writeoff                                                          | 5,817          |        |
| Four years before current fiscal year                                                                     | 91,705         | 43,760      |
| Four years before current fiscal year, writeoff                                                           | 328            |        |
| Prior                                                                                                     | 231,931        | 204,719     |
| Prior, writeoff                                                                                           | 1,875          |        |
| Revolving loans amortized cost basis                                                                      | 8,831          | 20,880      |
| Revolving loans amortized cost basis, writeoff                                                            | 0              |        |
| Revolving loans converted to term                                                                         | 0              | 0           |
| Revolving loans converted to term, writeoff                                                               | 0              |        |
| Total                                                                                                     | 966,807        | 932,892     |
| Total, writeoff                                                                                           | 24,330         |        |
| Public finance and other commercial loans | Pass                                                          |           |        |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                          |           |        |
| Current fiscal year                                                                                       | 61,235         | 187,125     |
| Fiscal year before current fiscal year                                                                    | 209,069        | 212,702     |
| Two years before current fiscal year                                                                      | 206,637        | 165,019     |
| Three years before current fiscal year                                                                    | 157,399        | 98,687      |
| Four years before current fiscal year                                                                     | 91,705         | 43,760      |
| Prior                                                                                                     | 231,931        | 204,719     |
| Revolving loans amortized cost basis                                                                      | 8,831          | 20,880      |
| Revolving loans converted to term                                                                         | 0              | 0           |
| Total                                                                                                     | $ 966,807      | $ 932,892   |

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+ References
Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-6
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