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Loans and Allowance for Credit Losses - Recorded Investment and Unpaid Principal Balance for Impaired Loans with Associated Allowance (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | $ 705 | $ 530 | $ 594
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 54,299 | 44,923 | 36,490
Financing Receivable, Nonaccrual | 61,456 | 39,472 |
Financing Receivable, Nonaccrual, Related Allowance | 7,965 | 4,549 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 89,536 | 62,321 |
Commercial Financial Agricultural And Other With No Related Allowance [Member] |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 41 | 143 | 157
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 6,580 | 7,895 | 3,751
Financing Receivable, Nonaccrual | 5,619 | 4,369 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 21,745 | 18,014 |
Commercial Financial Agricultural And Other With No Related Allowance [Member] | Time and demand loans |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 41 | 143 | 157
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 5,481 | 7,569 | 3,751
Financing Receivable, Nonaccrual | 4,813 | 3,527 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 20,939 | 17,172 |
Commercial Financial Agricultural And Other With No Related Allowance [Member] | Equipment Finance |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 |
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 0 | 326 |
Financing Receivable, Nonaccrual | 0 | 842 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 0 | 842 |
Commercial Financial Agricultural And Other With No Related Allowance [Member] | Time and Demand Loans Other |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 |
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 1,099 | 0 |
Financing Receivable, Nonaccrual | 806 | 0 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 806 | 0 |
Real Estate Construction With No Related Allowance [Member] |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 | 0
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 4,498 | 1,096 | 0
Financing Receivable, Nonaccrual | 2,529 | 3,288 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 2,581 | 3,288 |
Real Estate Construction With No Related Allowance [Member] | Construction Other |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 |
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 4,498 | 1,096 |
Financing Receivable, Nonaccrual | 2,529 | 3,288 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 2,581 | 3,288 |
Real Estate Construction With No Related Allowance [Member] | Construction Residential |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 |
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 0 | 0 |
Financing Receivable, Nonaccrual | 0 | 0 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 0 | 0 |
Residential real estate with no related allowance recorded [Member] |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 133 | 136 | 241
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 8,360 | 6,440 | 9,040
Financing Receivable, Nonaccrual | 8,875 | 7,042 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 10,524 | 8,763 |
Residential real estate with no related allowance recorded [Member] | Senior Lien |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 118 | 129 | 172
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 5,134 | 3,760 | 5,280
Financing Receivable, Nonaccrual | 6,020 | 4,161 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 6,993 | 5,151 |
Residential real estate with no related allowance recorded [Member] | Junior Lien |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 15 | 7 | 69
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 3,226 | 2,680 | 3,760
Financing Receivable, Nonaccrual | 2,855 | 2,881 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 3,531 | 3,612 |
Commercial Real Estate With No Related Allowance [Member] |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 453 | 260 | 172
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 16,759 | 20,715 | 22,983
Financing Receivable, Nonaccrual | 18,346 | 12,402 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 24,047 | 18,219 |
Commercial Real Estate With No Related Allowance [Member] | Multifamily |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 | 43
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 34 | 37 | 172
Financing Receivable, Nonaccrual | 20 | 55 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 21 | 58 |
Commercial Real Estate With No Related Allowance [Member] | Nonowner Occupied Commercial Real Estate |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 173 | 122 | 104
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 15,657 | 18,454 | 21,304
Financing Receivable, Nonaccrual | 16,948 | 10,971 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 22,372 | 17,092 |
Commercial Real Estate With No Related Allowance [Member] | Owner Occupied Commercial Real Estate |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 280 | 138 | 25
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 1,068 | 2,224 | 1,507
Financing Receivable, Nonaccrual | 1,378 | 1,376 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 1,654 | 1,069 |
Loans To Individuals With No Related Allowance [Member] |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 7 | 7 | 16
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 146 | 365 | 455
Financing Receivable, Nonaccrual | 250 | 166 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 2,237 | 259 |
Loans To Individuals With No Related Allowance [Member] | Other consumer loans |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 | 0
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 11 | 66 | 77
Financing Receivable, Nonaccrual | 103 | 2 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 157 | 2 |
Loans To Individuals With No Related Allowance [Member] | Automobile Loan |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 7 | 7 | 16
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 135 | 299 | 378
Financing Receivable, Nonaccrual | 147 | 164 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 2,080 | 257 |
Subtotal with no related allowance recorded [Member] |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 634 | 546 | 586
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 36,343 | 36,511 | 36,229
Financing Receivable, Nonaccrual | 35,619 | 27,267 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 61,134 | 48,543 |
Commercial, financial, agricultural and other With an allowance recorded [Member] |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 71 | (16) | 8
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 5,378 | 6,574 | 261
Financing Receivable, Nonaccrual | 9,368 | 5,691 |
Financing Receivable, Nonaccrual, Related Allowance | 4,724 | 4,044 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 10,459 | 6,787 |
Commercial, financial, agricultural and other With an allowance recorded [Member] | Time and demand loans |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 71 | (16) | 8
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 5,378 | 6,574 | 261
Financing Receivable, Nonaccrual | 9,368 | 5,691 |
Financing Receivable, Nonaccrual, Related Allowance | 4,724 | 4,044 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 10,459 | 6,787 |
Commercial, financial, agricultural and other With an allowance recorded [Member] | Equipment Finance |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 |
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 0 | 0 |
Financing Receivable, Nonaccrual | 0 | 0 |
Financing Receivable, Nonaccrual, Related Allowance | 0 | 0 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 0 | 0 |
Commercial, financial, agricultural and other With an allowance recorded [Member] | Time and Demand Loans Other |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 |
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 0 | 0 |
Financing Receivable, Nonaccrual | 0 | 0 |
Financing Receivable, Nonaccrual, Related Allowance | 0 | 0 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 0 | 0 |
Real estate construction with an allowance recorded [Member] |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 | 0
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 0 | 0 | 0
Financing Receivable, Nonaccrual | 0 | 0 |
Financing Receivable, Nonaccrual, Related Allowance | 0 | 0 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 0 | 0 |
Real estate construction with an allowance recorded [Member] | Construction Other |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 |
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 0 | 0 |
Financing Receivable, Nonaccrual | 0 | 0 |
Financing Receivable, Nonaccrual, Related Allowance | 0 | 0 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 0 | 0 |
Real estate construction with an allowance recorded [Member] | Construction Residential |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 |
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 0 | 0 |
Financing Receivable, Nonaccrual | 0 | 0 |
Financing Receivable, Nonaccrual, Related Allowance | 0 | 0 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 0 | 0 |
Residential real estate With an allowance recorded [Member] |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 | 0
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 1,486 | 1,183 | 0
Financing Receivable, Nonaccrual | 2,712 | 1,531 |
Financing Receivable, Nonaccrual, Related Allowance | 369 | 118 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 2,885 | 1,697 |
Residential real estate With an allowance recorded [Member] | Senior Lien |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 | 0
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 205 | 47 | 0
Financing Receivable, Nonaccrual | 1,114 | 282 |
Financing Receivable, Nonaccrual, Related Allowance | 47 | 39 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 1,113 | 279 |
Residential real estate With an allowance recorded [Member] | Junior Lien |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 | 0
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 1,281 | 1,136 | 0
Financing Receivable, Nonaccrual | 1,598 | 1,249 |
Financing Receivable, Nonaccrual, Related Allowance | 322 | 79 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 1,772 | 1,418 |
Commercial real estate With an allowance recorded [Member] |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 | 0
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 11,092 | 655 | 0
Financing Receivable, Nonaccrual | 13,757 | 4,983 |
Financing Receivable, Nonaccrual, Related Allowance | 2,872 | 387 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 15,058 | 5,294 |
Commercial real estate With an allowance recorded [Member] | Multifamily |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 | 0
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 0 | 0 | 0
Financing Receivable, Nonaccrual | 0 | 0 |
Financing Receivable, Nonaccrual, Related Allowance | 0 | 0 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 0 | 0 |
Commercial real estate With an allowance recorded [Member] | Nonowner Occupied Commercial Real Estate |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 | 0
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 6,634 | 397 | 0
Financing Receivable, Nonaccrual | 7,602 | 3,311 |
Financing Receivable, Nonaccrual, Related Allowance | 2,093 | 174 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 8,686 | 3,550 |
Commercial real estate With an allowance recorded [Member] | Owner Occupied Commercial Real Estate |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 | 0
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 4,458 | 258 | 0
Financing Receivable, Nonaccrual | 6,155 | 1,672 |
Financing Receivable, Nonaccrual, Related Allowance | 779 | 213 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 6,372 | 1,744 |
Loans to individuals With an allowance recorded [Member] |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 | 0
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 0 | 0 | 0
Financing Receivable, Nonaccrual | 0 | 0 |
Financing Receivable, Nonaccrual, Related Allowance | 0 | 0 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 0 | 0 |
Loans to individuals With an allowance recorded [Member] | Other consumer loans |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 | 0
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 0 | 0 | 0
Financing Receivable, Nonaccrual | 0 | 0 |
Financing Receivable, Nonaccrual, Related Allowance | 0 | 0 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 0 | 0 |
Loans to individuals With an allowance recorded [Member] | Automobile Loan |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 0 | 0 | 0
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 0 | 0 | 0
Financing Receivable, Nonaccrual | 0 | 0 |
Financing Receivable, Nonaccrual, Related Allowance | 0 | 0 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | 0 | 0 |
Subtotal With an allowance recorded [Member] |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Financing Receivable, Nonaccrual, Interest Income | 71 | (16) | 8
Financing Receivables, before Allowance for Credit Loss, Average Amount Outstanding | 17,956 | 8,412 | $ 261
Financing Receivable, Nonaccrual | 25,837 | 12,205 |
Financing Receivable, Nonaccrual, Related Allowance | 7,965 | 4,549 |
Financing Receivable, Nonaccrual, Unpaid Principal Balance | $ 28,402 | $ 13,778 |

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Data Type: | na
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