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Loans - Risk Category of Loans at Amortized Cost, by Portfolio Segment Based on Year of Origination (Detail) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Grand Total | $ 2,580,192 | $ 2,560,795
Consumer Real Estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 | 15,212 | 40,400
2024 | 38,410 | 64,555
2023 | 59,974 | 80,069
2022 | 78,318 | 91,137
2021 | 89,619 | 75,461
Prior | 177,404 | 107,166
Term Total | 458,937 | 458,788
Revolving Loans Amortized Cost Basis | 64,447 | 61,352
Revolving Loans Converted to Term | 320 | 252
Grand Total | 523,704 | 520,392
Gross charge-offs - Prior |  | 13
Gross charge-offs - Term Total |  | 13
Gross charge-offs - Grand Total |  | 13
Consumer Real Estate [Member] | Pass [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 | 15,212 | 40,257
2024 | 38,267 | 64,316
2023 | 59,741 | 79,503
2022 | 77,759 | 89,800
2021 | 88,204 | 74,996
Prior | 175,384 | 106,007
Term Total | 454,567 | 454,879
Revolving Loans Amortized Cost Basis | 64,194 | 61,097
Revolving Loans Converted to Term | 305 | 237
Grand Total | 519,066 | 516,213
Consumer Real Estate [Member] | Special Mention [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2023 |  | 37
2022 | 36 | 551
2021 | 135 |
Prior | 117 | 119
Term Total | 288 | 707
Revolving Loans Amortized Cost Basis | 19 | 19
Grand Total | 307 | 726
Consumer Real Estate [Member] | Substandard [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 |  | 143
2024 | 143 | 239
2023 | 233 | 529
2022 | 523 | 786
2021 | 1,280 | 465
Prior | 1,903 | 1,040
Term Total | 4,082 | 3,202
Revolving Loans Amortized Cost Basis | 234 | 236
Revolving Loans Converted to Term | 15 | 15
Grand Total | 4,331 | 3,453
Agricultural Real Estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 | 6,366 | 29,513
2024 | 28,100 | 28,088
2023 | 26,912 | 34,840
2022 | 34,032 | 22,983
2021 | 22,633 | 23,639
Prior | 97,525 | 76,982
Term Total | 215,568 | 216,045
Revolving Loans Amortized Cost Basis | 88 | 92
Grand Total | 215,656 | 216,137
Agricultural Real Estate [Member] | Pass [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 | 6,366 | 23,817
2024 | 22,431 | 28,088
2023 | 26,912 | 34,469
2022 | 33,661 | 22,983
2021 | 22,633 | 23,639
Prior | 97,422 | 76,964
Term Total | 209,425 | 209,960
Revolving Loans Amortized Cost Basis | 88 | 92
Grand Total | 209,513 | 210,052
Agricultural Real Estate [Member] | Special Mention [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Prior | 12 | 13
Term Total | 12 | 13
Grand Total | 12 | 13
Agricultural Real Estate [Member] | Substandard [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 |  | 5,696
2024 | 5,669 |
2023 |  | 371
2022 | 371 |
Prior | 91 | 5
Term Total | 6,131 | 6,072
Grand Total | 6,131 | 6,072
Agricultural [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 | 9,944 | 14,915
2024 | 12,389 | 10,534
2023 | 9,441 | 14,381
2022 | 12,229 | 5,624
2021 | 4,991 | 3,233
Prior | 6,327 | 3,911
Term Total | 55,321 | 52,598
Revolving Loans Amortized Cost Basis | 98,600 | 99,783
Grand Total | 153,921 | 152,381
Agricultural [Member] | Pass [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 | 9,944 | 14,915
2024 | 12,389 | 10,500
2023 | 9,423 | 14,381
2022 | 11,856 | 5,616
2021 | 4,985 | 3,204
Prior | 6,327 | 3,911
Term Total | 54,924 | 52,527
Revolving Loans Amortized Cost Basis | 94,013 | 98,283
Grand Total | 148,937 | 150,810
Agricultural [Member] | Special Mention [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2024 |  | 13
2022 | 373 | 8
2021 | 6 |
Term Total | 379 | 21
Revolving Loans Amortized Cost Basis | 3,116 | 30
Grand Total | 3,495 | 51
Agricultural [Member] | Substandard [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2024 |  | 21
2023 | 18 |
2021 |  | 29
Term Total | 18 | 50
Revolving Loans Amortized Cost Basis | 1,471 | 1,470
Grand Total | 1,489 | 1,520
Commercial Real Estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 | 54,325 | 128,608
2024 | 145,473 | 234,491
2023 | 238,525 | 425,696
2022 | 417,882 | 218,309
2021 | 215,108 | 111,787
Prior | 251,949 | 189,570
Term Total | 1,323,262 | 1,308,461
Grand Total | 1,323,262 | 1,308,461
Gross charge-offs - Prior |  | 15
Gross charge-offs - Term Total |  | 15
Gross charge-offs - Grand Total |  | 15
Commercial Real Estate [Member] | Pass [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 | 52,969 | 128,608
2024 | 145,421 | 200,192
2023 | 204,446 | 413,106
2022 | 404,021 | 218,309
2021 | 214,795 | 110,435
Prior | 249,291 | 188,239
Term Total | 1,270,943 | 1,258,889
Grand Total | 1,270,943 | 1,258,889
Commercial Real Estate [Member] | Special Mention [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 | 1,356 |
2023 |  | 12,590
2022 | 12,514 |
2021 | 313 | 1,352
Prior | 1,944 | 753
Term Total | 16,127 | 14,695
Grand Total | 16,127 | 14,695
Commercial Real Estate [Member] | Substandard [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2024 | 52 | 34,299
2023 | 34,079 |
2022 | 1,347 |
Prior | 714 | 578
Term Total | 36,192 | 34,877
Grand Total | 36,192 | 34,877
Commercial & Industrial [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 | 9,415 | 31,972
2024 | 28,325 | 55,066
2023 | 47,272 | 39,694
2022 | 35,844 | 15,235
2021 | 14,005 | 13,506
Prior | 11,339 | 1,738
Term Total | 146,200 | 157,211
Revolving Loans Amortized Cost Basis | 131,665 | 117,386
Revolving Loans Converted to Term | 78 | 222
Grand Total | 277,943 | 274,819
Gross charge-offs - fiscal year 2022 | 25 |
Gross charge-offs - fiscal year 2021 |  | 101
Gross charge-offs - Term Total | 25 | 101
Gross charge-offs - Revolving Loans Converted to Term |  | 5
Gross charge-offs - Grand Total | 25 | 106
Commercial & Industrial [Member] | Pass [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 | 9,415 | 31,933
2024 | 28,287 | 54,581
2023 | 46,818 | 39,665
2022 | 35,844 | 15,047
2021 | 13,786 | 13,480
Prior | 10,925 | 1,294
Term Total | 145,075 | 156,000
Revolving Loans Amortized Cost Basis | 127,302 | 113,446
Revolving Loans Converted to Term | 78 | 222
Grand Total | 272,455 | 269,668
Commercial & Industrial [Member] | Special Mention [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2024 |  | 137
2023 | 127 |
2022 |  | 188
2021 | 182 | 26
Prior | 386 | 416
Term Total | 695 | 767
Revolving Loans Amortized Cost Basis | 480 | 459
Grand Total | 1,175 | 1,226
Commercial & Industrial [Member] | Substandard [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 |  | 39
2024 | 38 | 348
2023 | 327 | 29
2021 | 37 |
Prior | 28 | 28
Term Total | 430 | 444
Revolving Loans Amortized Cost Basis | 3,883 | 3,481
Grand Total | 4,313 | 3,925
Consumer [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Grand Total | 60,721 | 63,627
Consumer [Member] | Payment Performance [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 | 5,760 | 13,477
2024 | 11,826 | 13,521
2023 | 12,038 | 27,304
2022 | 23,741 | 5,952
2021 | 4,935 | 2,314
Prior | 2,187 | 582
Term Total | 60,487 | 63,150
Revolving Loans Amortized Cost Basis | 234 | 477
Grand Total | 60,721 | 63,627
Gross charge-offs - fiscal year 2025 | 40 | 201
Gross charge-offs - fiscal year 2024 | 43 | 69
Gross charge-offs - fiscal year 2023 | 19 | 62
Gross charge-offs - fiscal year 2022 | 162 | 14
Gross charge-offs - fiscal year 2021 | 46 |
Gross charge-offs - Term Total | 310 | 346
Gross charge-offs - Grand Total | 310 | 346
Consumer [Member] | Performing [Member] | Payment Performance [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 | 5,760 | 13,437
2024 | 11,803 | 13,521
2023 | 12,036 | 27,264
2022 | 23,711 | 5,917
2021 | 4,923 | 2,310
Prior | 2,184 | 582
Term Total | 60,417 | 63,031
Revolving Loans Amortized Cost Basis | 234 | 477
Grand Total | 60,651 | 63,508
Consumer [Member] | Nonperforming [Member] | Payment Performance [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 |  | 40
2024 | 23 |
2023 | 2 | 40
2022 | 30 | 35
2021 | 12 | 4
Prior | 3 |
Term Total | 70 | 119
Grand Total | 70 | 119
Other Loan [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 | 600 |
2022 |  | 15,829
2021 | 15,666 | 5,068
Prior | 8,719 | 4,081
Term Total | 24,985 | 24,978
Grand Total | 24,985 | 24,978
Other Loan [Member] | Pass [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
2025 | 600 |
2022 |  | 15,829
2021 | 15,666 | 5,068
Prior | 8,719 | 4,081
Term Total | 24,985 | 24,978
Grand Total | $ 24,985 | $ 24,978

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