| Disaggregation of Revenue [Table Text Block] |
| | | Trust | | | Bank | | | | | |
| (In Thousands of Dollars) | | Segment | | | Segment | | | Totals | |
| For Three Months Ended June 30, 2026 | | | | | | | | | | | | |
| Service charges on deposit accounts | | $ | 0 | | | $ | 2,434 | | | $ | 2,434 | |
| Debit card and EFT fees | | | 0 | | | | 2,561 | | | | 2,561 | |
| Trust fees | | | 3,089 | | | | 0 | | | | 3,089 | |
| Insurance agency commissions | | | 0 | | | | 1,485 | | | | 1,485 | |
| Retirement plan consulting fees | | | 954 | | | | 0 | | | | 954 | |
| Investment commissions | | | 0 | | | | 1,044 | | | | 1,044 | |
| Other (outside the scope of ASC 606) | | | 0 | | | | 2,846 | | | | 2,846 | |
| Total noninterest income | | $ | 4,043 | | | $ | 10,370 | | | $ | 14,413 | |
| | | Trust | | | Bank | | | | | |
| (In Thousands of Dollars) | | Segment | | | Segment | | | Totals | |
| For Six Months Ended June 30, 2026 | | | | | | | | | | | | |
| Service charges on deposit accounts | | $ | 0 | | | $ | 4,400 | | | $ | 4,400 | |
| Debit card and EFT fees | | | 0 | | | | 4,584 | | | | 4,584 | |
| Trust fees | | | 6,119 | | | | 0 | | | | 6,119 | |
| Insurance agency commissions | | | 0 | | | | 3,168 | | | | 3,168 | |
| Retirement plan consulting fees | | | 1,840 | | | | 0 | | | | 1,840 | |
| Investment commissions | | | 0 | | | | 1,915 | | | | 1,915 | |
| Other (outside the scope of ASC 606) | | | 0 | | | | 6,074 | | | | 6,074 | |
| Total noninterest income | | $ | 7,959 | | | $ | 20,141 | | | $ | 28,100 | |
| | | Trust | | | Bank | | | | | |
| (In Thousands of Dollars) | | Segment | | | Segment | | | Totals | |
| For Three Months Ended June 30, 2025 | | | | | | | | | | | | |
| Service charges on deposit accounts | | $ | 0 | | | $ | 1,749 | | | $ | 1,749 | |
| Debit card and EFT fees | | | 0 | | | | 2,017 | | | | 2,017 | |
| Trust fees | | | 2,596 | | | | 0 | | | | 2,596 | |
| Insurance agency commissions | | | 0 | | | | 1,828 | | | | 1,828 | |
| Retirement plan consulting fees | | | 783 | | | | 0 | | | | 783 | |
| Investment commissions | | | 0 | | | | 721 | | | | 721 | |
| Other (outside the scope of ASC 606) | | | 0 | | | | 2,428 | | | | 2,428 | |
| Total noninterest income | | $ | 3,379 | | | $ | 8,743 | | | $ | 12,122 | |
| | | Trust | | | Bank | | | | | |
| (In Thousands of Dollars) | | Segment | | | Segment | | | Totals | |
| For Six Months Ended June 30, 2025 | | | | | | | | | | | | |
| Service charges on deposit accounts | | $ | 0 | | | $ | 3,507 | | | $ | 3,507 | |
| Debit card and EFT fees | | | 0 | | | | 3,882 | | | | 3,882 | |
| Trust fees | | | 5,237 | | | | 0 | | | | 5,237 | |
| Insurance agency commissions | | | 0 | | | | 3,569 | | | | 3,569 | |
| Retirement plan consulting fees | | | 1,581 | | | | 0 | | | | 1,581 | |
| Investment commissions | | | 0 | | | | 1,250 | | | | 1,250 | |
| Other (outside the scope of ASC 606) | | | 0 | | | | 3,577 | | | | 3,577 | |
| Total noninterest income | | $ | 6,818 | | | $ | 15,785 | | | $ | 22,603 | |
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