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Loans and Allowance for Credit Losses - Credit Risk Profile of Loan Portfolio on Amortized Cost Basis Based on Risk Rating Category (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
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Credit Quality Information [Abstract] |  |
Current fiscal year | $ 558,007 | $ 792,071
Fiscal year before current fiscal year | 699,958 | 1,402,051
Two years before current fiscal year | 1,312,925 | 994,108
Three years before current fiscal year | 929,158 | 619,354
Four years before current fiscal year | 564,300 | 381,174
Prior | 1,471,605 | 1,315,596
Revolving Loans | 78,637 | 76,211
Current period gross writeoffs, current fiscal year | 71 | 10
Current period gross writeoffs, fiscal year before current fiscal year | 190 | 761
Current period gross writeoffs, two year before current fiscal year | 622 | 208
Current period gross writeoffs, three year before current fiscal year | 556 | 51
Current period gross writeoffs, four year before current fiscal year | 58 | 93
Current period gross writeoffs, prior | 1,641 | 1,508
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 5,614,591 | 5,580,565
Current period gross writeoffs, total loans receivables | 3,138 | 2,631
Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 555,677 | 786,908
Fiscal year before current fiscal year | 695,258 | 1,390,885
Two years before current fiscal year | 1,301,213 | 976,531
Three years before current fiscal year | 918,731 | 616,020
Four years before current fiscal year | 561,719 | 376,655
Prior | 1,436,895 | 1,254,871
Revolving Loans | 77,910 | 75,700
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 5,547,403 | 5,477,570
Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 2,049 | 4,925
Fiscal year before current fiscal year | 1,529 | 5,566
Two years before current fiscal year | 5,793 | 15,110
Three years before current fiscal year | 9,044 | 2,721
Four years before current fiscal year | 1,638 | 3,368
Prior | 18,009 | 42,350
Revolving Loans | 88 | 10
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 38,151 | 74,050
Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 281 | 238
Fiscal year before current fiscal year | 3,171 | 5,600
Two years before current fiscal year | 5,919 | 2,467
Three years before current fiscal year | 1,383 | 613
Four years before current fiscal year | 943 | 1,151
Prior | 16,701 | 18,375
Revolving Loans | 639 | 501
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 29,037 | 28,945
Agricultural Loans |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 128,119 | 147,999
Fiscal year before current fiscal year | 56,668 | 27,905
Two years before current fiscal year | 26,016 | 10,044
Three years before current fiscal year | 15,584 | 2,549
Four years before current fiscal year | 3,110 | 1,921
Prior | 3,917 | 5,854
Revolving Loans | 0 | 0
Current period gross writeoffs, current fiscal year | 0 | 0
Current period gross writeoffs, fiscal year before current fiscal year | 64 | 276
Current period gross writeoffs, two year before current fiscal year | 100 | 0
Current period gross writeoffs, three year before current fiscal year | 52 | 0
Current period gross writeoffs, four year before current fiscal year | 0 | 0
Current period gross writeoffs, prior | 45 | 132
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 233,414 | 196,272
Current period gross writeoffs, total loans receivables | 261 | 408
Agricultural Loans | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 127,739 | 147,993
Fiscal year before current fiscal year | 54,805 | 27,895
Two years before current fiscal year | 25,999 | 10,044
Three years before current fiscal year | 15,584 | 2,549
Four years before current fiscal year | 3,110 | 1,883
Prior | 3,917 | 5,854
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 231,154 | 196,218
Agricultural Loans | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 327 | 6
Fiscal year before current fiscal year | 302 | 10
Two years before current fiscal year | 0 | 0
Three years before current fiscal year | 0 | 0
Four years before current fiscal year | 0 | 38
Prior | 0 | 0
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 629 | 54
Agricultural Loans | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 53 | 0
Fiscal year before current fiscal year | 1,561 | 0
Two years before current fiscal year | 17 | 0
Three years before current fiscal year | 0 | 0
Four years before current fiscal year | 0 | 0
Prior | 0 | 0
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,631 | 0
Commercial Industrial And Other Portfolio Segment |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 171,300 | 291,351
Fiscal year before current fiscal year | 264,169 | 309,188
Two years before current fiscal year | 284,306 | 242,971
Three years before current fiscal year | 203,627 | 155,119
Four years before current fiscal year | 126,019 | 74,532
Prior | 409,427 | 377,607
Revolving Loans | 0 | 0
Current period gross writeoffs, current fiscal year | 0 | 0
Current period gross writeoffs, fiscal year before current fiscal year | 47 | 353
Current period gross writeoffs, two year before current fiscal year | 207 | 0
Current period gross writeoffs, three year before current fiscal year | 378 | 49
Current period gross writeoffs, four year before current fiscal year | 10 | 20
Current period gross writeoffs, prior | 1 | 107
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,458,849 | 1,450,768
Current period gross writeoffs, total loans receivables | 643 | 529
Commercial Industrial And Other Portfolio Segment | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 171,046 | 290,304
Fiscal year before current fiscal year | 262,373 | 306,794
Two years before current fiscal year | 282,671 | 232,198
Three years before current fiscal year | 197,515 | 154,499
Four years before current fiscal year | 124,654 | 73,906
Prior | 401,109 | 347,957
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,439,368 | 1,405,658
Commercial Industrial And Other Portfolio Segment | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 189 | 1,047
Fiscal year before current fiscal year | 1,031 | 1,857
Two years before current fiscal year | 1,388 | 9,982
Three years before current fiscal year | 5,927 | 562
Four years before current fiscal year | 1,347 | 597
Prior | 7,662 | 28,900
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 17,545 | 42,945
Commercial Industrial And Other Portfolio Segment | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 65 | 0
Fiscal year before current fiscal year | 765 | 537
Two years before current fiscal year | 247 | 791
Three years before current fiscal year | 185 | 58
Four years before current fiscal year | 18 | 29
Prior | 656 | 750
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,936 | 2,165
Consumer Loans |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 4,678 | 9,633
Fiscal year before current fiscal year | 6,201 | 40,656
Two years before current fiscal year | 28,000 | 21,589
Three years before current fiscal year | 13,682 | 10,526
Four years before current fiscal year | 5,774 | 4,534
Prior | 4,887 | 4,076
Revolving Loans | 0 | 0
Current period gross writeoffs, current fiscal year | 71 | 22
Current period gross writeoffs, fiscal year before current fiscal year | 43 | 177
Current period gross writeoffs, two year before current fiscal year | 154 | 89
Current period gross writeoffs, three year before current fiscal year | 126 | 10
Current period gross writeoffs, four year before current fiscal year | 48 | 7
Current period gross writeoffs, prior | 1,198 | 1,075
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 63,222 | 91,014
Current period gross writeoffs, total loans receivables | 1,640 | 1,380
Consumer Loans | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 4,678 | 9,547
Fiscal year before current fiscal year | 6,171 | 40,225
Two years before current fiscal year | 27,723 | 21,264
Three years before current fiscal year | 13,491 | 10,387
Four years before current fiscal year | 5,671 | 4,475
Prior | 4,856 | 4,035
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 62,590 | 89,933
Consumer Loans | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 0
Fiscal year before current fiscal year | 0 | 26
Two years before current fiscal year | 24 | 0
Three years before current fiscal year | 0 | 0
Four years before current fiscal year | 0 | 0
Prior | 0 | 0
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 24 | 26
Consumer Loans | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 86
Fiscal year before current fiscal year | 30 | 405
Two years before current fiscal year | 253 | 325
Three years before current fiscal year | 191 | 139
Four years before current fiscal year | 103 | 59
Prior | 31 | 41
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 608 | 1,055
Real Estate Loan |  |
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 3,859,106 | 3,842,511
Real Estate Loan | Construction and Land Development |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 48,615 | 68,086
Fiscal year before current fiscal year | 78,688 | 74,065
Two years before current fiscal year | 19,267 | 27,392
Three years before current fiscal year | 16,051 | 5,188
Four years before current fiscal year | 5,290 | 10,795
Prior | 22,946 | 19,551
Revolving Loans | 0 | 0
Current period gross writeoffs, current fiscal year | 0 | 0
Current period gross writeoffs, fiscal year before current fiscal year | 0 | 0
Current period gross writeoffs, two year before current fiscal year | 0 | 0
Current period gross writeoffs, three year before current fiscal year | 0 | 0
Current period gross writeoffs, four year before current fiscal year | 0 | 14
Current period gross writeoffs, prior | 0 | 0
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 190,857 | 205,077
Current period gross writeoffs, total loans receivables | 0 | 14
Real Estate Loan | Construction and Land Development | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 48,615 | 68,086
Fiscal year before current fiscal year | 78,688 | 74,065
Two years before current fiscal year | 19,261 | 27,392
Three years before current fiscal year | 16,051 | 5,188
Four years before current fiscal year | 5,290 | 10,795
Prior | 22,542 | 19,115
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 190,447 | 204,641
Real Estate Loan | Construction and Land Development | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 0
Fiscal year before current fiscal year | 0 | 0
Two years before current fiscal year | 0 | 0
Three years before current fiscal year | 0 | 0
Four years before current fiscal year | 0 | 0
Prior | 390 | 0
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 390 | 0
Real Estate Loan | Construction and Land Development | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 0
Fiscal year before current fiscal year | 0 | 0
Two years before current fiscal year | 6 | 0
Three years before current fiscal year | 0 | 0
Four years before current fiscal year | 0 | 0
Prior | 14 | 436
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 20 | 436
Real Estate Loan | Agricultural |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 16,436 | 19,437
Fiscal year before current fiscal year | 19,210 | 164,812
Two years before current fiscal year | 158,601 | 58,813
Three years before current fiscal year | 55,492 | 53,249
Four years before current fiscal year | 51,161 | 20,589
Prior | 83,720 | 74,232
Revolving Loans | 0 | 0
Current period gross writeoffs, current fiscal year | 0 | 0
Current period gross writeoffs, fiscal year before current fiscal year | 0 | 0
Current period gross writeoffs, two year before current fiscal year | 0 | 0
Current period gross writeoffs, three year before current fiscal year | 0 | 0
Current period gross writeoffs, four year before current fiscal year | 0 | 0
Current period gross writeoffs, prior | 0 | 0
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 384,620 | 391,132
Current period gross writeoffs, total loans receivables | 0 | 0
Real Estate Loan | Agricultural | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 15,266 | 19,231
Fiscal year before current fiscal year | 18,873 | 164,812
Two years before current fiscal year | 157,635 | 57,815
Three years before current fiscal year | 54,503 | 53,249
Four years before current fiscal year | 51,161 | 19,419
Prior | 80,611 | 71,189
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 378,049 | 385,715
Real Estate Loan | Agricultural | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 1,170 | 206
Fiscal year before current fiscal year | 196 | 0
Two years before current fiscal year | 0 | 627
Three years before current fiscal year | 989 | 0
Four years before current fiscal year | 0 | 1,170
Prior | 2,028 | 1,868
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 4,383 | 3,871
Real Estate Loan | Agricultural | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 0
Fiscal year before current fiscal year | 141 | 0
Two years before current fiscal year | 966 | 371
Three years before current fiscal year | 0 | 0
Four years before current fiscal year | 0 | 0
Prior | 1,081 | 1,175
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,188 | 1,546
Real Estate Loan | Commercial And Multifamily Portfolio Segment |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 150,225 | 189,294
Fiscal year before current fiscal year | 235,608 | 686,704
Two years before current fiscal year | 719,347 | 550,570
Three years before current fiscal year | 545,144 | 319,254
Four years before current fiscal year | 306,238 | 241,661
Prior | 821,725 | 716,350
Revolving Loans | 0 | 0
Current period gross writeoffs, current fiscal year | 0 | 0
Current period gross writeoffs, fiscal year before current fiscal year | 0 | 0
Current period gross writeoffs, two year before current fiscal year | 151 | 0
Current period gross writeoffs, three year before current fiscal year | 0 | 0
Current period gross writeoffs, four year before current fiscal year | 0 | 25
Current period gross writeoffs, prior | 300 | 0
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,778,287 | 2,703,833
Current period gross writeoffs, total loans receivables | 451 | 25
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 149,862 | 185,628
Fiscal year before current fiscal year | 235,559 | 680,099
Two years before current fiscal year | 711,647 | 548,733
Three years before current fiscal year | 542,617 | 317,075
Four years before current fiscal year | 305,947 | 239,323
Prior | 806,776 | 701,464
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,752,408 | 2,672,322
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 363 | 3,666
Fiscal year before current fiscal year | 0 | 2,706
Two years before current fiscal year | 4,174 | 1,317
Three years before current fiscal year | 2,051 | 2,159
Four years before current fiscal year | 291 | 1,563
Prior | 7,367 | 7,778
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 14,246 | 19,189
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 0
Fiscal year before current fiscal year | 49 | 3,899
Two years before current fiscal year | 3,526 | 520
Three years before current fiscal year | 476 | 20
Four years before current fiscal year | 0 | 775
Prior | 7,582 | 7,108
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 11,633 | 12,322
1-4 Family | Real Estate Loan |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 38,634 | 66,271
Fiscal year before current fiscal year | 39,414 | 98,721
Two years before current fiscal year | 77,388 | 82,729
Three years before current fiscal year | 79,578 | 73,469
Four years before current fiscal year | 66,708 | 27,142
Prior | 124,983 | 117,926
Revolving Loans | 78,637 | 76,211
Current period gross writeoffs, current fiscal year | 0 | 10
Current period gross writeoffs, fiscal year before current fiscal year | 36 | 0
Current period gross writeoffs, two year before current fiscal year | 10 | 0
Current period gross writeoffs, three year before current fiscal year | 0 | 0
Current period gross writeoffs, four year before current fiscal year | 0 | 14
Current period gross writeoffs, prior | 97 | 63
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 505,342 | 542,469
Current period gross writeoffs, total loans receivables | 143 | 87
1-4 Family | Real Estate Loan | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 38,471 | 66,119
Fiscal year before current fiscal year | 38,789 | 96,995
Two years before current fiscal year | 76,277 | 79,085
Three years before current fiscal year | 78,970 | 73,073
Four years before current fiscal year | 65,886 | 26,854
Prior | 117,084 | 105,257
Revolving Loans | 77,910 | 75,700
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 493,387 | 523,083
1-4 Family | Real Estate Loan | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 0
Fiscal year before current fiscal year | 0 | 967
Two years before current fiscal year | 207 | 3,184
Three years before current fiscal year | 77 | 0
Four years before current fiscal year | 0 | 0
Prior | 562 | 3,804
Revolving Loans | 88 | 10
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 934 | 7,965
1-4 Family | Real Estate Loan | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 163 | 152
Fiscal year before current fiscal year | 625 | 759
Two years before current fiscal year | 904 | 460
Three years before current fiscal year | 531 | 396
Four years before current fiscal year | 822 | 288
Prior | 7,337 | 8,865
Revolving Loans | 639 | 501
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | $ 11,021 | $ 11,421

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