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Note 4 - Loans and Allowance for Credit Losses - Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Dec. 31, 2024
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | $ 59,929 |  | $ 35,843 |  | $ 35,843
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | 2,407 | [1] | 799 | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | (812) |  | (205) |  | (4,698)
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 405 |  | 147 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 61,929 |  | 36,584 |  | 59,929
Consumer Borrower [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 9,799 |  | 7,872 |  | 7,872
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | 213 | [1] | 101 | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | (643) |  | (12) |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 112 |  | 13 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 9,481 |  | 7,974 |  | 9,799
Consumer Borrower [Member] | Commercial Portfolio Segment [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 8,170 |  | 9,705 |  | 9,705
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | (311) | [1] | (156) | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | (169) |  | (164) |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 270 |  | 123 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 7,960 |  | 9,508 |  | 8,170
Consumer Borrower [Member] | Residential Portfolio Segment [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 9,359 |  | 7,671 |  | 7,671
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | 373 | [1] | 118 | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | (604) |  | 0 |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 0 |  | 0 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 9,128 |  | 7,789 |  | 9,359
Consumer Borrower [Member] | Residential Portfolio Segment [Member] | Real Estate, First Lien [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 6,921 |  | 6,087 |  | 6,087
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | 175 | [1] | 64 | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | (54) |  | 0 |  | 0
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 0 |  | 0 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 7,042 |  | 6,151 |  | 6,921
Consumer Borrower [Member] | Residential Portfolio Segment [Member] | Construction Loans [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 357 |  | 485 |  | 485
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | 110 | [1] | 4 | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | 0 |  | 0 |  | 0
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 0 |  | 0 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 467 |  | 489 |  | 357
Consumer Borrower [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 1,339 |  | 835 |  | 835
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | 91 | [1] | 30 | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | (250) |  | 0 |  | (19)
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 0 |  | 0 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 1,180 |  | 865 |  | 1,339
Consumer Borrower [Member] | Residential Portfolio Segment [Member] | Real Estate, Junior Lien [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 742 |  | 264 |  | 264
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | (3) | [1] | 20 | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | (300) |  | 0 |  | (638)
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 0 |  | 0 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 439 |  | 284 |  | 742
Consumer Borrower [Member] | Consumer Portfolio Segment [Member] | Consumer, Other [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 440 |  | 201 |  | 201
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | (160) | [1] | (17) | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | (39) |  | (12) |  | (51)
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 112 |  | 13 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 353 |  | 185 |  | 440
Commercial Borrower [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 50,130 |  | 27,971 |  | 27,971
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | 2,194 | [1] | 698 | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | (169) |  | (193) |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 293 |  | 134 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 52,448 |  | 28,610 |  | 50,130
Commercial Borrower [Member] | Commercial Portfolio Segment [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | (169) |  |  |  | (3,727)
Commercial Borrower [Member] | Commercial Real Estate Portfolio Segment [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 40,732 |  | 18,086 |  | 18,086
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | 2,229 | [1] | 567 | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | 0 |  | (29) |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 11 |  | 11 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 42,972 |  | 18,635 |  | 40,732
Commercial Borrower [Member] | Commercial Real Estate Portfolio Segment [Member] | Construction, Land, and Development [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 16,277 |  | 6,135 |  | 6,135
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | 2,092 | [1] | (213) | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | 0 |  | 0 |  | 0
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 0 |  | 0 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 18,369 |  | 5,922 |  | 16,277
Commercial Borrower [Member] | Commercial Real Estate Portfolio Segment [Member] | Multifamily Loan [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 4,716 |  | 1,776 |  | 1,776
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | 33 | [1] | 372 | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | 0 |  | 0 |  | 0
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 0 |  | 0 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 4,749 |  | 2,148 |  | 4,716
Commercial Borrower [Member] | Commercial Real Estate Portfolio Segment [Member] | Non-Owner Occupied [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 16,513 |  | 7,726 |  | 7,726
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | (171) | [1] | 379 | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | 0 |  | 0 |  | 0
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 0 |  | 0 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 16,342 |  | 8,105 |  | 16,513
Commercial Borrower [Member] | Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loans [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 3,226 |  | 2,449 |  | 2,449
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | 275 | [1] | 29 | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | 0 |  | (29) |  | (237)
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 11 |  | 11 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 3,512 |  | 2,460 |  | 3,226
Commercial Borrower [Member] | Agricultural Real Estate Portfolio Segment [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 1,228 |  | 180 |  | 180
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | 276 | [1] | 287 | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | 0 |  | 0 |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 12 |  | 0 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 1,516 |  | 467 |  | 1,228
Commercial Borrower [Member] | Agricultural Real Estate Portfolio Segment [Member] | Land [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 597 |  | 96 |  | 96
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | 6 | [1] | 152 | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | 0 |  | 0 |  | 0
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 0 |  | 0 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | 603 |  | 248 |  | 597
Commercial Borrower [Member] | Agricultural Real Estate Portfolio Segment [Member] | Production Loans [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Beginning Balance | 631 |  | 84 |  | 84
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Provisions | 270 | [1] | 135 | [2] |
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Charge-offs | 0 |  | 0 |  | (26)
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Recovery | 12 |  | 0 |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | $ 913 |  | $ 219 |  | $ 631
[1] | The difference in the credit loss expense reported herein compared to the consolidated statements of income is associated with the credit loss expense of ($1.5) million related to off-balance sheet credit exposure and ($2) thousand related to HTM investment securities.
[2] | The difference in the credit loss expense reported herein compared to the consolidated statements of income is associated with the credit loss expense of ($793) million related to off-balance sheet credit exposure and ($6) thousand related to HTM investment securities.

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- Definition Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 + Details
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