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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, 2023 | Dec. 31, 2022
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Credit Quality Information [Abstract] |  |
Current fiscal year | $ 629,933 | $ 1,535,342
Fiscal year before current fiscal year | 1,492,232 | 973,016
Two years before current fiscal year | 1,069,403 | 669,475
Three years before current fiscal year | 660,141 | 387,967
Four years before current fiscal year | 403,520 | 354,435
Prior | 1,213,373 | 862,255
Revolving Loans | 71,463 | 43,722
Current period gross writeoffs, current fiscal year | 0 | 311
Current period gross writeoffs, fiscal year before current fiscal year | 333 | 603
Current period gross writeoffs, two year before current fiscal year | 83 | 195
Current period gross writeoffs, three year before current fiscal year | 50 | 462
Current period gross writeoffs, four year before current fiscal year | 62 | 30
Current period gross writeoffs, prior | 1,053 | 1,349
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 5,540,065 | 4,826,212
Current period gross writeoffs, total loans receivables | 1,581 | 2,950
Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 625,828 | 1,524,905
Fiscal year before current fiscal year | 1,480,981 | 969,145
Two years before current fiscal year | 1,050,906 | 656,609
Three years before current fiscal year | 649,637 | 382,543
Four years before current fiscal year | 398,814 | 335,886
Prior | 1,158,180 | 832,814
Revolving Loans | 71,412 | 43,722
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 5,435,758 | 4,745,624
Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 3,965 | 5,126
Fiscal year before current fiscal year | 5,245 | 2,163
Two years before current fiscal year | 15,910 | 11,356
Three years before current fiscal year | 9,836 | 4,118
Four years before current fiscal year | 3,446 | 8,814
Prior | 35,320 | 12,891
Revolving Loans | 10 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 73,732 | 44,468
Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 140 | 5,311
Fiscal year before current fiscal year | 6,006 | 1,708
Two years before current fiscal year | 2,587 | 1,510
Three years before current fiscal year | 668 | 1,306
Four years before current fiscal year | 1,260 | 9,735
Prior | 19,873 | 16,550
Revolving Loans | 41 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 30,575 | 36,120
Agricultural Loans |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 113,700 | 138,558
Fiscal year before current fiscal year | 40,541 | 18,783
Two years before current fiscal year | 16,473 | 3,433
Three years before current fiscal year | 4,355 | 4,720
Four years before current fiscal year | 1,979 | 981
Prior | 2,399 | 363
Revolving Loans | 0 | 0
Current period gross writeoffs, current fiscal year | 0 | 0
Current period gross writeoffs, fiscal year before current fiscal year | 276 | 93
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 | 132 | 0
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 179,447 | 166,838
Current period gross writeoffs, total loans receivables | 408 | 93
Agricultural Loans | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 113,694 | 137,327
Fiscal year before current fiscal year | 40,523 | 18,783
Two years before current fiscal year | 16,470 | 3,433
Three years before current fiscal year | 4,355 | 3,918
Four years before current fiscal year | 1,961 | 915
Prior | 2,399 | 254
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 179,402 | 164,630
Agricultural Loans | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 6 | 1,178
Fiscal year before current fiscal year | 18 | 0
Two years before current fiscal year | 0 | 0
Three years before current fiscal year | 0 | 756
Four years before current fiscal year | 15 | 66
Prior | 0 | 109
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 39 | 2,109
Agricultural Loans | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 53
Fiscal year before current fiscal year | 0 | 0
Two years before current fiscal year | 3 | 0
Three years before current fiscal year | 0 | 46
Four years before current fiscal year | 3 | 0
Prior | 0 | 0
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 6 | 99
Commercial Industrial And Other Portfolio Segment |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 243,750 | 450,816
Fiscal year before current fiscal year | 323,945 | 227,096
Two years before current fiscal year | 253,290 | 182,487
Three years before current fiscal year | 162,159 | 64,511
Four years before current fiscal year | 87,402 | 69,366
Prior | 349,890 | 248,195
Revolving Loans | 0 | 0
Current period gross writeoffs, current fiscal year | 0 | 39
Current period gross writeoffs, fiscal year before current fiscal year | 0 | 311
Current period gross writeoffs, two year before current fiscal year | 0 | 39
Current period gross writeoffs, three year before current fiscal year | 49 | 439
Current period gross writeoffs, four year before current fiscal year | 0 | 23
Current period gross writeoffs, prior | 13 | 19
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,420,436 | 1,242,471
Current period gross writeoffs, total loans receivables | 62 | 870
Commercial Industrial And Other Portfolio Segment | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 243,700 | 450,001
Fiscal year before current fiscal year | 321,790 | 226,038
Two years before current fiscal year | 241,780 | 172,208
Three years before current fiscal year | 154,578 | 63,906
Four years before current fiscal year | 86,721 | 61,929
Prior | 327,485 | 247,404
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,376,054 | 1,221,486
Commercial Industrial And Other Portfolio Segment | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 50 | 469
Fiscal year before current fiscal year | 1,634 | 640
Two years before current fiscal year | 10,634 | 10,095
Three years before current fiscal year | 7,510 | 570
Four years before current fiscal year | 647 | 7,280
Prior | 21,563 | 158
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 42,038 | 19,212
Commercial Industrial And Other Portfolio Segment | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 346
Fiscal year before current fiscal year | 521 | 418
Two years before current fiscal year | 876 | 184
Three years before current fiscal year | 71 | 35
Four years before current fiscal year | 34 | 157
Prior | 842 | 633
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,344 | 1,773
Consumer Loans |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 8,973 | 48,669
Fiscal year before current fiscal year | 45,278 | 21,352
Two years before current fiscal year | 24,506 | 12,105
Three years before current fiscal year | 12,325 | 8,011
Four years before current fiscal year | 5,488 | 2,002
Prior | 2,972 | 5,636
Revolving Loans | 0 | 0
Current period gross writeoffs, current fiscal year | 0 | 22
Current period gross writeoffs, fiscal year before current fiscal year | 57 | 177
Current period gross writeoffs, two year before current fiscal year | 83 | 89
Current period gross writeoffs, three year before current fiscal year | 1 | 10
Current period gross writeoffs, four year before current fiscal year | 9 | 7
Current period gross writeoffs, prior | 845 | 1,075
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 99,542 | 97,775
Current period gross writeoffs, total loans receivables | 995 | 1,380
Consumer Loans | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 8,929 | 48,600
Fiscal year before current fiscal year | 44,835 | 21,088
Two years before current fiscal year | 24,253 | 12,101
Three years before current fiscal year | 12,165 | 7,968
Four years before current fiscal year | 5,427 | 1,945
Prior | 2,930 | 5,630
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 98,539 | 97,332
Consumer Loans | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 0
Fiscal year before current fiscal year | 9 | 18
Two years before current fiscal year | 0 | 1
Three years before current fiscal year | 0 | 0
Four years before current fiscal year | 0 | 5
Prior | 0 | 0
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 9 | 24
Consumer Loans | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 44 | 69
Fiscal year before current fiscal year | 434 | 246
Two years before current fiscal year | 253 | 3
Three years before current fiscal year | 160 | 43
Four years before current fiscal year | 61 | 52
Prior | 42 | 6
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 994 | 419
Real Estate Loan |  |
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 3,840,640 | 3,319,128
Real Estate Loan | Construction and Land Development |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 49,485 | 63,846
Fiscal year before current fiscal year | 78,795 | 39,790
Two years before current fiscal year | 29,330 | 12,558
Three years before current fiscal year | 6,101 | 15,801
Four years before current fiscal year | 10,218 | 1,210
Prior | 15,277 | 11,059
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 |  | 2
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 189,206 | 144,264
Current period gross writeoffs, total loans receivables | 14 | 2
Real Estate Loan | Construction and Land Development | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 49,485 | 63,846
Fiscal year before current fiscal year | 78,795 | 39,790
Two years before current fiscal year | 29,330 | 12,558
Three years before current fiscal year | 6,101 | 15,787
Four years before current fiscal year | 10,218 | 1,210
Prior | 14,834 | 10,601
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 188,763 | 143,792
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 | 14
Four years before current fiscal year | 0 | 0
Prior | 443 | 458
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 443 | 472
Real Estate Loan | Agricultural |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 12,474 | 172,956
Fiscal year before current fiscal year | 172,028 | 67,115
Two years before current fiscal year | 59,717 | 58,773
Three years before current fiscal year | 56,006 | 25,060
Four years before current fiscal year | 22,284 | 29,229
Prior | 77,325 | 57,194
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 | 399,834 | 410,327
Current period gross writeoffs, total loans receivables | 0 | 0
Real Estate Loan | Agricultural | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 12,265 | 171,833
Fiscal year before current fiscal year | 172,028 | 67,115
Two years before current fiscal year | 58,648 | 58,283
Three years before current fiscal year | 56,006 | 23,820
Four years before current fiscal year | 21,114 | 27,573
Prior | 74,179 | 52,799
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 394,240 | 401,423
Real Estate Loan | Agricultural | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 209 | 1,123
Fiscal year before current fiscal year | 0 | 0
Two years before current fiscal year | 694 | 490
Three years before current fiscal year | 0 | 1,240
Four years before current fiscal year | 1,170 | 273
Prior | 1,945 | 3,121
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 4,018 | 6,247
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 | 375 | 0
Three years before current fiscal year | 0 | 0
Four years before current fiscal year | 0 | 1,383
Prior | 1,201 | 1,274
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,576 | 2,657
Real Estate Loan | Commercial And Multifamily Portfolio Segment |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 161,227 | 564,891
Fiscal year before current fiscal year | 728,921 | 511,379
Two years before current fiscal year | 580,701 | 320,612
Three years before current fiscal year | 338,421 | 241,945
Four years before current fiscal year | 248,302 | 217,851
Prior | 662,329 | 467,679
Revolving Loans |  | 0
Current period gross writeoffs, current fiscal year | 0 | 250
Current period gross writeoffs, fiscal year before current fiscal year | 0 | 22
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 | 142
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,719,901 | 2,324,357
Current period gross writeoffs, total loans receivables | 25 | 414
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 157,527 | 558,921
Fiscal year before current fiscal year | 721,955 | 509,614
Two years before current fiscal year | 578,816 | 319,049
Three years before current fiscal year | 336,064 | 239,564
Four years before current fiscal year | 245,896 | 211,505
Prior | 645,950 | 453,076
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,686,208 | 2,291,729
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 3,700 | 2,187
Fiscal year before current fiscal year | 2,735 | 1,287
Two years before current fiscal year | 1,348 | 769
Three years before current fiscal year | 2,326 | 1,508
Four years before current fiscal year | 1,614 | 952
Prior | 7,987 | 8,503
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 19,710 | 15,206
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 3,783
Fiscal year before current fiscal year | 4,231 | 478
Two years before current fiscal year | 537 | 794
Three years before current fiscal year | 31 | 873
Four years before current fiscal year | 792 | 5,394
Prior | 8,392 | 6,100
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 13,983 | 17,422
1-4 Family | Real Estate Loan |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 40,324 | 95,606
Fiscal year before current fiscal year | 102,724 | 87,501
Two years before current fiscal year | 105,386 | 79,507
Three years before current fiscal year | 80,774 | 27,919
Four years before current fiscal year | 27,847 | 33,796
Prior | 103,181 | 72,129
Revolving Loans | 71,463 | 43,722
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 | 67
Current period gross writeoffs, three year before current fiscal year | 0 | 13
Current period gross writeoffs, four year before current fiscal year | 14 | 0
Current period gross writeoffs, prior | 63 | 111
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 531,699 | 440,180
Current period gross writeoffs, total loans receivables | 77 | 191
1-4 Family | Real Estate Loan | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 40,228 | 94,377
Fiscal year before current fiscal year | 101,055 | 86,717
Two years before current fiscal year | 101,609 | 78,977
Three years before current fiscal year | 80,368 | 27,580
Four years before current fiscal year | 27,477 | 30,809
Prior | 90,403 | 63,050
Revolving Loans | 71,412 | 43,722
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 512,552 | 425,232
1-4 Family | Real Estate Loan | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 169
Fiscal year before current fiscal year | 849 | 218
Two years before current fiscal year | 3,234 | 1
Three years before current fiscal year | 0 | 44
Four years before current fiscal year | 0 | 238
Prior | 3,825 | 1,000
Revolving Loans | 10 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 7,918 | 1,670
1-4 Family | Real Estate Loan | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 96 | 1,060
Fiscal year before current fiscal year | 820 | 566
Two years before current fiscal year | 543 | 529
Three years before current fiscal year | 406 | 295
Four years before current fiscal year | 370 | 2,749
Prior | 8,953 | 8,079
Revolving Loans | 41 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | $ 11,229 | $ 13,278

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