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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 | Mar. 31, 2024 | Dec. 31, 2023
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Credit Quality Information [Abstract] |  |
Current fiscal year | $ 115,715 | $ 792,071
Fiscal year before current fiscal year | 778,434 | 1,402,051
Two years before current fiscal year | 1,405,307 | 994,108
Three years before current fiscal year | 1,019,248 | 619,354
Four years before current fiscal year | 612,374 | 381,174
Prior | 1,497,590 | 1,315,596
Revolving Loans | 70,626 | 76,211
Current period gross writeoffs, current fiscal year | 0 | 10
Current period gross writeoffs, fiscal year before current fiscal year | 39 | 761
Current period gross writeoffs, two year before current fiscal year | 51 | 208
Current period gross writeoffs, three year before current fiscal year | 406 | 51
Current period gross writeoffs, four year before current fiscal year | 0 | 93
Current period gross writeoffs, prior | 323 | 1,508
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 5,499,295 | 5,580,565
Current period gross writeoffs, total loans receivables | 819 | 2,631
Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 114,406 | 786,908
Fiscal year before current fiscal year | 773,142 | 1,390,885
Two years before current fiscal year | 1,394,065 | 976,531
Three years before current fiscal year | 1,004,765 | 616,020
Four years before current fiscal year | 609,437 | 376,655
Prior | 1,438,441 | 1,254,871
Revolving Loans | 70,050 | 75,700
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 5,404,306 | 5,477,570
Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 1,283 | 4,925
Fiscal year before current fiscal year | 4,908 | 5,566
Two years before current fiscal year | 5,258 | 15,110
Three years before current fiscal year | 12,560 | 2,721
Four years before current fiscal year | 2,183 | 3,368
Prior | 39,500 | 42,350
Revolving Loans | 0 | 10
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 65,693 | 74,050
Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 26 | 238
Fiscal year before current fiscal year | 384 | 5,600
Two years before current fiscal year | 5,984 | 2,467
Three years before current fiscal year | 1,923 | 613
Four years before current fiscal year | 754 | 1,151
Prior | 19,649 | 18,375
Revolving Loans | 576 | 501
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 29,296 | 28,945
Agricultural Loans |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 38,758 | 147,999
Fiscal year before current fiscal year | 121,403 | 27,905
Two years before current fiscal year | 30,846 | 10,044
Three years before current fiscal year | 16,192 | 2,549
Four years before current fiscal year | 3,402 | 1,921
Prior | 2,616 | 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 | 0 | 276
Current period gross writeoffs, two year before current fiscal year | 0 | 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 | 0 | 132
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 213,217 | 196,272
Current period gross writeoffs, total loans receivables | 52 | 408
Agricultural Loans | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 38,758 | 147,993
Fiscal year before current fiscal year | 121,171 | 27,895
Two years before current fiscal year | 30,478 | 10,044
Three years before current fiscal year | 16,192 | 2,549
Four years before current fiscal year | 3,396 | 1,883
Prior | 1,852 | 5,854
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 211,847 | 196,218
Agricultural Loans | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 6
Fiscal year before current fiscal year | 11 | 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 | 748 | 0
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 759 | 54
Agricultural Loans | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 0
Fiscal year before current fiscal year | 221 | 0
Two years before current fiscal year | 368 | 0
Three years before current fiscal year | 0 | 0
Four years before current fiscal year | 6 | 0
Prior | 16 | 0
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 611 | 0
Commercial Industrial And Other Portfolio Segment |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 33,337 | 291,351
Fiscal year before current fiscal year | 279,679 | 309,188
Two years before current fiscal year | 307,759 | 242,971
Three years before current fiscal year | 240,856 | 155,119
Four years before current fiscal year | 141,263 | 74,532
Prior | 400,331 | 377,607
Revolving Loans |  | 0
Current period gross writeoffs, current fiscal year | 0 | 0
Current period gross writeoffs, fiscal year before current fiscal year | 0 | 353
Current period gross writeoffs, two year before current fiscal year | 0 | 0
Current period gross writeoffs, three year before current fiscal year | 273 | 49
Current period gross writeoffs, four year before current fiscal year | 0 | 20
Current period gross writeoffs, prior | 1 | 107
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,403,226 | 1,450,768
Current period gross writeoffs, total loans receivables | 274 | 529
Commercial Industrial And Other Portfolio Segment | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 33,234 | 290,304
Fiscal year before current fiscal year | 278,618 | 306,794
Two years before current fiscal year | 305,634 | 232,198
Three years before current fiscal year | 233,432 | 154,499
Four years before current fiscal year | 139,860 | 73,906
Prior | 375,188 | 347,957
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,365,966 | 1,405,658
Commercial Industrial And Other Portfolio Segment | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 103 | 1,047
Fiscal year before current fiscal year | 1,061 | 1,857
Two years before current fiscal year | 1,528 | 9,982
Three years before current fiscal year | 7,073 | 562
Four years before current fiscal year | 1,359 | 597
Prior | 24,394 | 28,900
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 35,519 | 42,945
Commercial Industrial And Other Portfolio Segment | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 0
Fiscal year before current fiscal year | 0 | 537
Two years before current fiscal year | 597 | 791
Three years before current fiscal year | 351 | 58
Four years before current fiscal year | 44 | 29
Prior | 749 | 750
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,741 | 2,165
Consumer Loans |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 1,612 | 9,633
Fiscal year before current fiscal year | 8,211 | 40,656
Two years before current fiscal year | 36,665 | 21,589
Three years before current fiscal year | 17,999 | 10,526
Four years before current fiscal year | 8,524 | 4,534
Prior | 6,558 | 4,076
Revolving Loans | 0 | 0
Current period gross writeoffs, current fiscal year | 0 | 22
Current period gross writeoffs, fiscal year before current fiscal year | 3 | 177
Current period gross writeoffs, two year before current fiscal year | 51 | 89
Current period gross writeoffs, three year before current fiscal year | 81 | 10
Current period gross writeoffs, four year before current fiscal year | 0 | 7
Current period gross writeoffs, prior | 291 | 1,075
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 79,569 | 91,014
Current period gross writeoffs, total loans receivables | 426 | 1,380
Consumer Loans | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 1,612 | 9,547
Fiscal year before current fiscal year | 8,161 | 40,225
Two years before current fiscal year | 36,304 | 21,264
Three years before current fiscal year | 17,758 | 10,387
Four years before current fiscal year | 8,383 | 4,475
Prior | 6,473 | 4,035
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 78,691 | 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 | 23 | 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 | 23 | 26
Consumer Loans | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 86
Fiscal year before current fiscal year | 50 | 405
Two years before current fiscal year | 338 | 325
Three years before current fiscal year | 241 | 139
Four years before current fiscal year | 141 | 59
Prior | 85 | 41
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 855 | 1,055
Real Estate Loan |  |
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 3,803,283 | 3,842,511
Real Estate Loan | Construction and Land Development |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 3,584 | 68,086
Fiscal year before current fiscal year | 81,753 | 74,065
Two years before current fiscal year | 56,302 | 27,392
Three years before current fiscal year | 16,509 | 5,188
Four years before current fiscal year | 5,781 | 10,795
Prior | 22,922 | 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 | 186,851 | 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 | 3,584 | 68,086
Fiscal year before current fiscal year | 81,753 | 74,065
Two years before current fiscal year | 56,302 | 27,392
Three years before current fiscal year | 16,509 | 5,188
Four years before current fiscal year | 5,781 | 10,795
Prior | 22,499 | 19,115
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 186,428 | 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 | 0 | 0
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 0 | 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 | 0 | 0
Three years before current fiscal year | 0 | 0
Four years before current fiscal year | 0 | 0
Prior | 423 | 436
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 423 | 436
Real Estate Loan | Agricultural |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 10,100 | 19,437
Fiscal year before current fiscal year | 19,069 | 164,812
Two years before current fiscal year | 162,999 | 58,813
Three years before current fiscal year | 57,260 | 53,249
Four years before current fiscal year | 52,598 | 20,589
Prior | 86,915 | 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 | 388,941 | 391,132
Current period gross writeoffs, total loans receivables | 0 | 0
Real Estate Loan | Agricultural | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 8,930 | 19,231
Fiscal year before current fiscal year | 18,867 | 164,812
Two years before current fiscal year | 162,999 | 57,815
Three years before current fiscal year | 56,265 | 53,249
Four years before current fiscal year | 52,598 | 19,419
Prior | 83,981 | 71,189
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 383,640 | 385,715
Real Estate Loan | Agricultural | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 1,170 | 206
Fiscal year before current fiscal year | 202 | 0
Two years before current fiscal year | 0 | 627
Three years before current fiscal year | 628 | 0
Four years before current fiscal year | 0 | 1,170
Prior | 1,864 | 1,868
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 3,864 | 3,871
Real Estate Loan | Agricultural | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 0
Fiscal year before current fiscal year | 0 | 0
Two years before current fiscal year | 0 | 371
Three years before current fiscal year | 367 | 0
Four years before current fiscal year | 0 | 0
Prior | 1,070 | 1,175
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,437 | 1,546
Real Estate Loan | Commercial And Multifamily Portfolio Segment |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 9,492 | 189,294
Fiscal year before current fiscal year | 209,743 | 686,704
Two years before current fiscal year | 713,007 | 550,570
Three years before current fiscal year | 572,219 | 319,254
Four years before current fiscal year | 322,032 | 241,661
Prior | 882,357 | 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 | 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 | 25
Current period gross writeoffs, prior | 0 | 0
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,708,850 | 2,703,833
Current period gross writeoffs, total loans receivables | 0 | 25
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 9,482 | 185,628
Fiscal year before current fiscal year | 206,109 | 680,099
Two years before current fiscal year | 706,392 | 548,733
Three years before current fiscal year | 570,053 | 317,075
Four years before current fiscal year | 321,198 | 239,323
Prior | 865,221 | 701,464
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,678,455 | 2,672,322
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 10 | 3,666
Fiscal year before current fiscal year | 3,634 | 2,706
Two years before current fiscal year | 2,854 | 1,317
Three years before current fiscal year | 1,716 | 2,159
Four years before current fiscal year | 824 | 1,563
Prior | 8,647 | 7,778
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 17,685 | 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 | 0 | 3,899
Two years before current fiscal year | 3,761 | 520
Three years before current fiscal year | 450 | 20
Four years before current fiscal year | 10 | 775
Prior | 8,489 | 7,108
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 12,710 | 12,322
1-4 Family | Real Estate Loan |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 18,832 | 66,271
Fiscal year before current fiscal year | 58,576 | 98,721
Two years before current fiscal year | 97,729 | 82,729
Three years before current fiscal year | 98,213 | 73,469
Four years before current fiscal year | 78,774 | 27,142
Prior | 95,891 | 117,926
Revolving Loans | 70,626 | 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 | 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 | 31 | 63
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 518,641 | 542,469
Current period gross writeoffs, total loans receivables | 67 | 87
1-4 Family | Real Estate Loan | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 18,806 | 66,119
Fiscal year before current fiscal year | 58,463 | 96,995
Two years before current fiscal year | 95,956 | 79,085
Three years before current fiscal year | 94,556 | 73,073
Four years before current fiscal year | 78,221 | 26,854
Prior | 83,227 | 105,257
Revolving Loans | 70,050 | 75,700
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 499,279 | 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 | 853 | 3,184
Three years before current fiscal year | 3,143 | 0
Four years before current fiscal year | 0 | 0
Prior | 3,847 | 3,804
Revolving Loans | 0 | 10
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 7,843 | 7,965
1-4 Family | Real Estate Loan | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 26 | 152
Fiscal year before current fiscal year | 113 | 759
Two years before current fiscal year | 920 | 460
Three years before current fiscal year | 514 | 396
Four years before current fiscal year | 553 | 288
Prior | 8,817 | 8,865
Revolving Loans | 576 | 501
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | $ 11,519 | $ 11,421

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