| Financing Receivables [Text Block] |
Loans:
Loan balances were as follows:
| (In Thousands of Dollars) | | June 30, 2026 | | | December 31, 2025 | |
| Commercial real estate | | | | | | | | |
| Owner occupied | | $ | 627,421 | | | $ | 393,061 | |
| Non-owner occupied | | | 1,016,924 | | | | 710,468 | |
| Farmland | | | 228,228 | | | | 211,370 | |
| Other | | | 378,388 | | | | 294,587 | |
| Commercial | | | | | | | | |
| Commercial and industrial | | | 592,431 | | | | 340,224 | |
| Agricultural | | | 56,799 | | | | 54,195 | |
| Residential real estate | | | | | | | | |
| 1-4 family residential | | | 1,230,110 | | | | 850,300 | |
| Home equity lines of credit | | | 360,685 | | | | 181,544 | |
| Consumer | | | | | | | | |
| Indirect | | | 239,209 | | | | 231,242 | |
| Direct | | | 21,375 | | | | 16,483 | |
| Other | | | 12,306 | | | | 10,070 | |
| Total loans | | $ | 4,763,876 | | | $ | 3,293,544 | |
| Net deferred loan costs | | | 12,601 | | | | 11,169 | |
| Allowance for credit losses | | | (53,285 | ) | | | (36,811 | ) |
| Net loans | | $ | 4,723,192 | | | $ | 3,267,902 | |
Allowance for credit loss activity
The following tables present the activity in the allowance for credit losses by portfolio segment for the three and six month periods ended June 30, 2026 and 2025:
Three Months Ended June 30, 2026
| | | Commercial | | | | | | | Residential | | | | | | | | | |
| (In Thousands of Dollars) | | Real Estate | | | Commercial | | | Real Estate | | | Consumer | | | Total | |
| Allowance for credit losses | | | | | | | | | | | | | | | | | | | | |
| Beginning balance | | $ | 30,049 | | | $ | 8,041 | | | $ | 11,331 | | | $ | 5,263 | | | $ | 54,684 | |
| (Credit) Provision for credit losses | | | 1,747 | | | | (111 | ) | | | (257 | ) | | | 695 | | | | 2,074 | |
| Initial allowance on purchased seasoned loans | | | 0 | | | | 160 | | | | 0 | | | | 0 | | | | 160 | |
| Loans charged off | | | (3,125 | ) | | | (188 | ) | | | (69 | ) | | | (421 | ) | | | (3,803 | ) |
| Recoveries | | | 0 | | | | 48 | | | | 47 | | | | 75 | | | | 170 | |
| Total ending allowance balance | | $ | 28,671 | | | $ | 7,950 | | | $ | 11,052 | | | $ | 5,612 | | | $ | 53,285 | |
Six Months Ended June 30, 2026
| | | Commercial | | | | | | | Residential | | | | | | | | | |
| (In Thousands of Dollars) | | Real Estate | | | Commercial | | | Real Estate | | | Consumer | | | Total | |
| Allowance for credit losses | | | | | | | | | | | | | | | | | | | | |
| Beginning balance | | $ | 20,064 | | | $ | 4,536 | | | $ | 7,241 | | | $ | 4,970 | | | $ | 36,811 | |
| (Credit) Provision for credit losses | | | (24 | ) | | | 218 | | | | (244 | ) | | | 1,111 | | | | 1,061 | |
| Initial allowance on loans purchased with credit deterioration | | | 3,380 | | | | 600 | | | | 15 | | | | 0 | | | | 3,995 | |
| Initial allowance on purchased seasoned loans | | | 8,377 | | | | 2,906 | | | | 4,102 | | | | 110 | | | | 15,495 | |
| Loans charged off | | | (3,126 | ) | | | (479 | ) | | | (152 | ) | | | (775 | ) | | | (4,532 | ) |
| Recoveries | | | 0 | | | | 169 | | | | 90 | | | | 196 | | | | 455 | |
| Total ending allowance balance | | $ | 28,671 | | | $ | 7,950 | | | $ | 11,052 | | | $ | 5,612 | | | $ | 53,285 | |
Three Months Ended June 30, 2025
| | | Commercial | | | | | | | Residential | | | | | | | | | |
| (In Thousands of Dollars) | | Real Estate | | | Commercial | | | Real Estate | | | Consumer | | | Total | |
| Allowance for credit losses | | | | | | | | | | | | | | | | | | | | |
| Beginning balance | | $ | 19,480 | | | $ | 4,383 | | | $ | 7,065 | | | $ | 4,621 | | | $ | 35,549 | |
| (Credit) Provision for credit losses | | | 2,149 | | | | 901 | | | | 191 | | | | 345 | | | | 3,586 | |
| Loans charged off | | | (22 | ) | | | (341 | ) | | | (58 | ) | | | (327 | ) | | | (748 | ) |
| Recoveries | | | 20 | | | | 30 | | | | 12 | | | | 114 | | | | 176 | |
| Total ending allowance balance | | $ | 21,627 | | | $ | 4,973 | | | $ | 7,210 | | | $ | 4,753 | | | $ | 38,563 | |
Six Months Ended June 30, 2025
| | | Commercial | | | | | | | Residential | | | | | | | | | |
| (In Thousands of Dollars) | | Real Estate | | | Commercial | | | Real Estate | | | Consumer | | | Total | |
| Allowance for credit losses | | | | | | | | | | | | | | | | | | | | |
| Beginning balance | | $ | 19,259 | | | $ | 4,628 | | | $ | 7,271 | | | $ | 4,705 | | | $ | 35,863 | |
| (Credit) Provision for credit losses | | | 2,412 | | | | 776 | | | | (43 | ) | | | 463 | | | | 3,608 | |
| Loans charged off | | | (66 | ) | | | (654 | ) | | | (77 | ) | | | (649 | ) | | | (1,446 | ) |
| Recoveries | | | 22 | | | | 223 | | | | 59 | | | | 234 | | | | 538 | |
| Total ending allowance balance | | $ | 21,627 | | | $ | 4,973 | | | $ | 7,210 | | | $ | 4,753 | | | $ | 38,563 | |
The cumulative loss rate used as the basis for the estimate of credit losses is comprised of the Company's historical loss experience from December 31, 2011 to June 30, 2026. As of June 30, 2026, the Company expects that the markets in which it operates will experience minimal changes to economic conditions, stable trend in unemployment rate, and an increased trend of delinquencies. Management adjusted historical loss experience for these expectations. No reversion adjustments were necessary, as the starting point for the Company's estimate was a cumulative loss rate covering the expected contractual term of the portfolio. While there are many factors that go into the calculation of the allowance for credit losses, the change in the balances from June 30, 2025 to June 30, 2026, is largely attributed to the Middlefield Merger. The increase related to the Middlefield Merger was partially offset by charge offs related to the settlement or sale of the debt or collateral associated with two commercial real estate non-owner occupied relationships and one multifamily relationship, and improving loss ratios of various loan portfolio segments.
The following tables present the amortized cost basis of loans on nonaccrual status and loans past due over 89 days still accruing as of June 30, 2026 and December 31, 2025:
| | | Nonaccrual with | | | Nonaccrual with | | | Loans past due | |
| | | no allowance | | | an allowance | | | over 89 days | |
| (In Thousands of Dollars) | | for credit loss | | | for credit loss | | | still accruing | |
| June 30, 2026 | | | | | | | | | | | | |
| Commercial real estate | | | | | | | | | | | | |
| Owner occupied | | $ | 4,196 | | | $ | 2,580 | | | $ | 0 | |
| Non-owner occupied | | | 2,227 | | | | 10,576 | | | | 0 | |
| Farmland | | | 0 | | | | 1,813 | | | | 0 | |
| Other | | | 491 | | | | 1,041 | | | | 0 | |
| Commercial | | | | | | | | | | | | |
| Commercial and industrial | | | 11,454 | | | | 3,651 | | | | 0 | |
| Agricultural | | | 0 | | | | 178 | | | | 0 | |
| Residential real estate | | | | | | | | | | | | |
| 1-4 family residential | | | 1,651 | | | | 2,543 | | | | 295 | |
| Home equity lines of credit | | | 487 | | | | 802 | | | | 0 | |
| Consumer | | | | | | | | | | | | |
| Indirect | | | 27 | | | | 503 | | | | 0 | |
| Direct | | | 0 | | | | 24 | | | | 0 | |
| Other | | | 0 | | | | 97 | | | | 0 | |
| Total loans | | $ | 20,533 | | | $ | 23,808 | | | $ | 295 | |
| | | Nonaccrual with | | | Nonaccrual with | | | Loans past due | |
| | | no allowance | | | an allowance | | | over 89 days | |
| (In Thousands of Dollars) | | for credit loss | | | for credit loss | | | still accruing | |
| December 31, 2025 | | | | | | | | | | | | |
| Commercial real estate | | | | | | | | | | | | |
| Owner occupied | | $ | 1,346 | | | $ | 207 | | | $ | 0 | |
| Non-owner occupied | | | 2,408 | | | | 10,776 | | | | 0 | |
| Farmland | | | 0 | | | | 1,917 | | | | 0 | |
| Other | | | 1,093 | | | | 0 | | | | 0 | |
| Commercial | | | | | | | | | | | | |
| Commercial and industrial | | | 0 | | | | 2,778 | | | | 82 | |
| Agricultural | | | 0 | | | | 159 | | | | 0 | |
| Residential real estate | | | | | | | | | | | | |
| 1-4 family residential | | | 1,095 | | | | 2,329 | | | | 271 | |
| Home equity lines of credit | | | 424 | | | | 689 | | | | 0 | |
| Consumer | | | | | | | | | | | | |
| Indirect | | | 61 | | | | 462 | | | | 0 | |
| Direct | | | 0 | | | | 21 | | | | 0 | |
| Other | | | 97 | | | | 0 | | | | 0 | |
| Total loans | | $ | 6,524 | | | $ | 19,338 | | | $ | 353 | |
There were no loans that were held for sale and in nonaccrual status for the periods ending June 30, 2026 and December 31, 2025.
The following tables present the amortized cost basis of collateral-dependent loans by class of loans as of June 30, 2026 and December 31, 2025:
| (In Thousands of Dollars) | | Real Estate | | | Business Assets | | | Vehicles | | | Cash | |
| June 30, 2026 | | | | | | | | | | | | | | | | |
| Commercial real estate | | | | | | | | | | | | | | | | |
| Owner occupied | | $ | 6,548 | | | $ | 0 | | | $ | 0 | | | $ | 0 | |
| Non-owner occupied | | | 27,567 | | | | 0 | | | | 0 | | | | 0 | |
| Farmland | | | 1,821 | | | | 0 | | | | 0 | | | | 0 | |
| Other | | | 1,552 | | | | 0 | | | | 0 | | | | 0 | |
| Commercial | | | | | | | | | | | | | | | | |
| Commercial and industrial | | | 0 | | | | 14,510 | | | | 0 | | | | 0 | |
| Agricultural | | | 0 | | | | 8 | | | | 0 | | | | 0 | |
| Residential real estate | | | | | | | | | | | | | | | | |
| 1-4 family residential | | | 2,851 | | | | 0 | | | | 0 | | | | 0 | |
| Home equity lines of credit | | | 889 | | | | 0 | | | | 0 | | | | 0 | |
| Consumer | | | | | | | | | | | | | | | | |
| Indirect | | | 0 | | | | 0 | | | | 67 | | | | 0 | |
| Direct | | | 0 | | | | 0 | | | | 1 | | | | 0 | |
| Other | | | 97 | | | | 0 | | | | 0 | | | | 0 | |
| Total loans | | $ | 41,325 | | | $ | 14,518 | | | $ | 68 | | | $ | 0 | |
| (In Thousands of Dollars) | | Real Estate | | | Business Assets | | | Vehicles | | | Cash | |
| December 31, 2025 | | | | | | | | | | | | | | | | |
| Commercial real estate | | | | | | | | | | | | | | | | |
| Owner occupied | | $ | 1,346 | | | $ | 0 | | | $ | 0 | | | $ | 0 | |
| Non-owner occupied | | | 24,235 | | | | 0 | | | | 0 | | | | 0 | |
| Farmland | | | 1,872 | | | | 0 | | | | 0 | | | | 0 | |
| Other | | | 1,093 | | | | 0 | | | | 0 | | | | 0 | |
| Commercial | | | | | | | | | | | | | | | | |
| Commercial and industrial | | | 0 | | | | 2,352 | | | | 0 | | | | 0 | |
| Agricultural | | | 0 | | | | 0 | | | | 0 | | | | 0 | |
| Residential real estate | | | | | | | | | | | | | | | | |
| 1-4 family residential | | | 2,411 | | | | 0 | | | | 0 | | | | 0 | |
| Home equity lines of credit | | | 944 | | | | 0 | | | | 0 | | | | 0 | |
| Consumer | | | | | | | | | | | | | | | | |
| Indirect | | | 0 | | | | 0 | | | | 102 | | | | 0 | |
| Direct | | | 0 | | | | 0 | | | | 4 | | | | 0 | |
| Other | | | 97 | | | | 0 | | | | 0 | | | | 0 | |
| Total loans | | $ | 31,998 | | | $ | 2,352 | | | $ | 106 | | | $ | 0 | |
The following tables present the aging of the amortized cost basis in past due loans as of June 30, 2026 and December 31, 2025 by class of loans.
| | | | | | | | | | | 90 Days | | | | | | | | | | | | | |
| | | | | | | | | | | or More | | | | | | | | | | | | | |
| | | 30-59 Days | | | 60-89 Days | | | Past Due | | | Total | | | Loans Not | | | | | |
| (In Thousands of Dollars) | | Past Due | | | Past Due | | | and Nonaccrual | | | Past Due | | | Past Due | | | Total | |
| June 30, 2026 | | | | | | | | | | | | | | | | | | | | | | | | |
| Commercial real estate | | | | | | | | | | | | | | | | | | | | | | | | |
| Owner occupied | | $ | 697 | | | $ | 506 | | | $ | 6,776 | | | $ | 7,979 | | | $ | 619,288 | | | $ | 627,267 | |
| Non-owner occupied | | | 48 | | | | 378 | | | | 12,803 | | | | 13,229 | | | | 1,003,345 | | | | 1,016,574 | |
| Farmland | | | 182 | | | | 6 | | | | 1,813 | | | | 2,001 | | | | 226,078 | | | | 228,079 | |
| Other | | | 991 | | | | 0 | | | | 1,532 | | | | 2,523 | | | | 375,186 | | | | 377,709 | |
| Commercial | | | | | | | | | | | | | | | | | | | | | | | | |
| Commercial and industrial | | | 1,099 | | | | 227 | | | | 15,105 | | | | 16,431 | | | | 577,624 | | | | 594,055 | |
| Agricultural | | | 170 | | | | 55 | | | | 178 | | | | 403 | | | | 57,380 | | | | 57,783 | |
| Residential real estate | | | | | | | | | | | | | | | | | | | | | | | | |
| 1-4 family residential | | | 9,331 | | | | 2,089 | | | | 4,489 | | | | 15,909 | | | | 1,215,359 | | | | 1,231,268 | |
| Home equity lines of credit | | | 416 | | | | 210 | | | | 1,289 | | | | 1,915 | | | | 359,128 | | | | 361,043 | |
| Consumer | | | | | | | | | | | | | | | | | | | | | | | | |
| Indirect | | | 1,640 | | | | 680 | | | | 530 | | | | 2,850 | | | | 246,077 | | | | 248,927 | |
| Direct | | | 45 | | | | 6 | | | | 24 | | | | 75 | | | | 21,387 | | | | 21,462 | |
| Other | | | 92 | | | | 1 | | | | 97 | | | | 190 | | | | 12,120 | | | | 12,310 | |
| Total loans | | $ | 14,711 | | | $ | 4,158 | | | $ | 44,636 | | | $ | 63,505 | | | $ | 4,712,972 | | | $ | 4,776,477 | |
| | | | | | | | | | | 90 Days | | | | | | | | | | | | | |
| | | | | | | | | | | or More | | | | | | | | | | | | | |
| | | 30-59 Days | | | 60-89 Days | | | Past Due | | | Total | | | Loans Not | | | | | |
| (In Thousands of Dollars) | | Past Due | | | Past Due | | | and Nonaccrual | | | Past Due | | | Past Due | | | Total | |
| December 31, 2025 | | | | | | | | | | | | | | | | | | | | | | | | |
| Commercial real estate | | | | | | | | | | | | | | | | | | | | | | | | |
| Owner occupied | | $ | 419 | | | $ | 1,018 | | | $ | 1,553 | | | $ | 2,990 | | | $ | 389,881 | | | $ | 392,871 | |
| Non-owner occupied | | | 8 | | | | 0 | | | | 13,184 | | | | 13,192 | | | | 696,884 | | | | 710,076 | |
| Farmland | | | 116 | | | | 163 | | | | 1,917 | | | | 2,196 | | | | 209,035 | | | | 211,231 | |
| Other | | | 0 | | | | 0 | | | | 1,093 | | | | 1,093 | | | | 292,915 | | | | 294,008 | |
| Commercial | | | | | | | | | | | | | | | | | | | | | | | | |
| Commercial and industrial | | | 1,064 | | | | 174 | | | | 2,860 | | | | 4,098 | | | | 337,639 | | | | 341,737 | |
| Agricultural | | | 235 | | | | 30 | | | | 159 | | | | 424 | | | | 54,665 | | | | 55,089 | |
| Residential real estate | | | | | | | | | | | | | | | | | | | | | | | | |
| 1-4 family residential | | | 9,848 | | | | 1,122 | | | | 3,695 | | | | 14,665 | | | | 836,515 | | | | 851,180 | |
| Home equity lines of credit | | | 75 | | | | 54 | | | | 1,113 | | | | 1,242 | | | | 180,544 | | | | 181,786 | |
| Consumer | | | | | | | | | | | | | | | | | | | | | | | | |
| Indirect | | | 2,090 | | | | 470 | | | | 523 | | | | 3,083 | | | | 237,027 | | | | 240,110 | |
| Direct | | | 37 | | | | 7 | | | | 21 | | | | 65 | | | | 16,486 | | | | 16,551 | |
| Other | | | 17 | | | | 0 | | | | 97 | | | | 114 | | | | 9,960 | | | | 10,074 | |
| Total loans | | $ | 13,909 | | | $ | 3,038 | | | $ | 26,215 | | | $ | 43,162 | | | $ | 3,261,551 | | | $ | 3,304,713 | |
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