| Segment Reporting [Table Text Block] |
| | Trust | | | Bank | | | Consolidated | |
(In Thousands of Dollars) | | Segment | | | Segment | | | Segment totals | |
For Three Months Ended September 30, 2026 | | | | | | | | | | | | |
Interest income - loans including fees | | $ | 0 | | | $ | 73,958 | | | $ | 73,958 | |
Interest income - investments | | | 0 | | | | 12,940 | | | | 12,940 | |
Trust fees | | | 3,178 | | | | 0 | | | | 3,178 | |
Retirement plan consulting fees | | | 899 | | | | 0 | | | | 899 | |
Total consolidated segment revenues | | | 4,077 | | | | 86,898 | | | | 90,975 | |
Reconciliation of revenue | | | | | | | | | | | | |
Other revenues | | | | | | | | | | | 5,474 | |
Total consolidated revenues | | | | | | | | | | | 96,449 | |
| | | | | | | | | | | | |
Interest expense - deposits | | | 0 | | | | 25,463 | | | | 25,463 | |
Interest expense - borrowings | | | 0 | | | | 5,117 | | | | 5,117 | |
Credit for credit losses and unfunded loans | | | 0 | | | | 2,792 | | | | 2,792 | |
Payroll expenses | | | 1,791 | | | | 20,725 | | | | 22,516 | |
Total consolidated segment expenses | | | 1,791 | | | | 54,097 | | | | 55,888 | |
| | | | | | | | | | | | |
Segment profit | | | 2,286 | | | | 32,801 | | | | 35,087 | |
Reconciliation of expenses | | | | | | | | | | | | |
Other expenses * | | | | | | | | | | | 24,126 | |
Total consolidated expenses | | | | | | | | | | | 80,014 | |
| | | | | | | | | | | | |
Total consolidated income before taxes | | | | | | | | | | $ | 16,435 | |
Other segment disclosures | | | | | | | | | | | | |
Occupancy and equipment | | | 135 | | | | 5,544 | | | | 5,679 | |
Intangible amortization | | | 14 | | | | 1,200 | | | | 1,214 | |
| | Trust | | | Bank | | | Consolidated | |
(In Thousands of Dollars) | | Segment | | | Segment | | | Segment totals | |
For Nine Months Ended September 30, 2026 | | | | | | | | | | | | |
Interest income - loans including fees | | $ | 0 | | | $ | 202,043 | | | $ | 202,043 | |
Interest income - investments | | | 0 | | | | 35,000 | | | | 35,000 | |
Trust fees | | | 9,297 | | | | 0 | | | | 9,297 | |
Retirement plan consulting fees | | | 2,739 | | | | 0 | | | | 2,739 | |
Total consolidated segment revenues | | | 12,036 | | | | 237,043 | | | | 249,079 | |
Reconciliation of revenue | | | | | | | | | | | | |
Other revenues | | | | | | | | | | | 28,680 | |
Total consolidated revenues | | | | | | | | | | | 277,759 | |
| | | | | | | | | | | | |
Interest expense - deposits | | | 0 | | | | 71,888 | | | | 71,888 | |
Interest expense - borrowings | | | 0 | | | | 13,302 | | | | 13,302 | |
Provision for credit losses and unfunded loans | | | 0 | | | | 4,196 | | | | 4,196 | |
Payroll expenses | | | 5,128 | | | | 57,162 | | | | 62,290 | |
Total consolidated segment expenses | | | 5,128 | | | | 146,548 | | | | 151,676 | |
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Segment profit | | | 6,908 | | | | 90,495 | | | | 97,403 | |
Reconciliation of expenses | | | | | | | | | | | | |
Other expenses * | | | | | | | | | | | 62,543 | |
Total consolidated expenses | | | | | | | | | | | 214,219 | |
| | | | | | | | | | | | |
Total consolidated income before taxes | | | | | | | | | | $ | 63,540 | |
Other segment disclosures | | | | | | | | | | | | |
Occupancy and equipment | | | 402 | | | | 16,276 | | | | 16,678 | |
Intangible amortization | | | 40 | | | | 3,234 | | | | 3,274 | |
| | Trust | | | Bank | | | Consolidated | |
(In Thousands of Dollars) | | Segment | | | Segment | | | Segment totals | |
For Three Months Ended September 30, 2025 | | | | | | | | | | | | |
Interest income - loans including fees | | $ | 0 | | | $ | 48,603 | | | $ | 48,603 | |
Interest income - investments | | | 0 | | | | 9,809 | | | | 9,809 | |
Trust fees | | | 2,745 | | | | 0 | | | | 2,745 | |
Retirement plan consulting fees | | | 1,060 | | | | 0 | | | | 1,060 | |
Total consolidated segment revenues | | | 3,805 | | | | 58,412 | | | | 62,217 | |
Reconciliation of revenue | | | | | | | | | | | | |
Other revenues | | | | | | | | | | | 8,579 | |
Total consolidated revenues | | | | | | | | | | | 70,796 | |
| | | | | | | | | | | | |
Interest expense - deposits | | | 0 | | | | 20,372 | | | | 20,372 | |
Interest expense - borrowings | | | 0 | | | | 2,687 | | | | 2,687 | |
Provision for credit losses and unfunded loans | | | 0 | | | | 1,419 | | | | 1,419 | |
Payroll expenses | | | 1,525 | | | | 14,443 | | | | 15,968 | |
Total consolidated segment expenses | | | 1,525 | | | | 38,921 | | | | 40,446 | |
| | | | | | | | | | | | |
Segment profit | | | 2,280 | | | | 19,491 | | | | 21,771 | |
Reconciliation of expenses | | | | | | | | | | | | |
Other expenses * | | | | | | | | | | | 15,711 | |
Total consolidated expenses | | | | | | | | | | | 56,157 | |
| | | | | | | | | | | | |
Total consolidated income before taxes | | | | | | | | | | $ | 14,639 | |
Other segment disclosures | | | | | | | | | | | | |
Occupancy and equipment | | | 143 | | | | 4,217 | | | | 4,360 | |
Intangible amortization | | | 23 | | | | 695 | | | | 718 | |
| | Trust | | | Bank | | | Consolidated | |
(In Thousands of Dollars) | | Segment | | | Segment | | | Segment totals | |
For Nine Months Ended September 30, 2025 | | | | | | | | | | | | |
Interest income - loans including fees | | $ | 0 | | | $ | 142,361 | | | $ | 142,361 | |
Interest income - investments | | | 0 | | | | 29,052 | | | | 29,052 | |
Trust fees | | | 7,982 | | | | 0 | | | | 7,982 | |
Retirement plan consulting fees | | | 2,641 | | | | 0 | | | | 2,641 | |
Total consolidated segment revenues | | | 10,623 | | | | 171,413 | | | | 182,036 | |
Reconciliation of revenue | | | | | | | | | | | | |
Other revenues | | | | | | | | | | | 26,370 | |
Total consolidated revenues | | | | | | | | | | | 208,406 | |
| | | | | | | | | | | | |
Interest expense - deposits | | | 0 | | | | 60,329 | | | | 60,329 | |
Interest expense - borrowings | | | 0 | | | | 8,620 | | | | 8,620 | |
Provision for credit losses and unfunded loans | | | 0 | | | | 4,763 | | | | 4,763 | |
Payroll expenses | | | 4,440 | | | | 42,382 | | | | 46,822 | |
Total consolidated segment expenses | | | 4,440 | | | | 116,094 | | | | 120,534 | |
| | | | | | | | | | | | |
Segment profit | | | 6,183 | | | | 55,319 | | | | 61,502 | |
Reconciliation of expenses | | | | | | | | | | | | |
Other expenses * | | | | | | | | | | | 40,559 | |
Total consolidated expenses | | | | | | | | | | | 161,093 | |
| | | | | | | | | | | | |
Total consolidated income before taxes | | | | | | | | | | $ | 47,313 | |
Other segment disclosures | | | | | | | | | | | | |
Occupancy and equipment | | | 426 | | | | 12,165 | | | | 12,591 | |
Intangible amortization | | | 69 | | | | 2,119 | | | | 2,188 | |
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