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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 | Jun. 30, 2023 | Dec. 31, 2022
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Credit Quality Information [Abstract] |  |
Current fiscal year | $ 302,193 | $ 1,535,342
Fiscal year before current fiscal year | 1,411,174 | 973,016
Two years before current fiscal year | 943,090 | 669,475
Three years before current fiscal year | 632,275 | 387,967
Four years before current fiscal year | 364,425 | 354,435
Prior | 1,117,833 | 862,255
Revolving Loans | 42,426 | 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 | 532 | 1,349
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 4,813,416 | 4,826,212
Current period gross writeoffs, total loans receivables | 1,060 | 2,950
Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 301,984 | 1,524,905
Fiscal year before current fiscal year | 1,402,433 | 969,145
Two years before current fiscal year | 932,637 | 656,609
Three years before current fiscal year | 622,813 | 382,543
Four years before current fiscal year | 360,885 | 335,886
Prior | 1,081,296 | 832,814
Revolving Loans | 42,426 | 43,722
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 4,744,474 | 4,745,624
Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 36 | 5,126
Fiscal year before current fiscal year | 3,591 | 2,163
Two years before current fiscal year | 8,867 | 11,356
Three years before current fiscal year | 8,764 | 4,118
Four years before current fiscal year | 2,372 | 8,814
Prior | 17,057 | 12,891
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 40,687 | 44,468
Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 173 | 5,311
Fiscal year before current fiscal year | 5,150 | 1,708
Two years before current fiscal year | 1,586 | 1,510
Three years before current fiscal year | 698 | 1,306
Four years before current fiscal year | 1,168 | 9,735
Prior | 19,480 | 16,550
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 28,255 | 36,120
Agricultural Loans |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 63,715 | 138,558
Fiscal year before current fiscal year | 58,321 | 18,783
Two years before current fiscal year | 18,170 | 3,433
Three years before current fiscal year | 4,488 | 4,720
Four years before current fiscal year | 2,195 | 981
Prior | 1,429 | 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 | 0 | 0
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 148,318 | 166,838
Current period gross writeoffs, total loans receivables | 276 | 93
Agricultural Loans | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 63,709 | 137,327
Fiscal year before current fiscal year | 57,549 | 18,783
Two years before current fiscal year | 18,115 | 3,433
Three years before current fiscal year | 4,488 | 3,918
Four years before current fiscal year | 2,155 | 915
Prior | 1,429 | 254
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 147,445 | 164,630
Agricultural Loans | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 6 | 1,178
Fiscal year before current fiscal year | 677 | 0
Two years before current fiscal year | 0 | 0
Three years before current fiscal year | 0 | 756
Four years before current fiscal year | 36 | 66
Prior | 0 | 109
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 719 | 2,109
Agricultural Loans | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 53
Fiscal year before current fiscal year | 95 | 0
Two years before current fiscal year | 55 | 0
Three years before current fiscal year | 0 | 46
Four years before current fiscal year | 4 | 0
Prior | 0 | 0
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 154 | 99
Commercial Industrial And Other Portfolio Segment |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 99,877 | 450,816
Fiscal year before current fiscal year | 415,506 | 227,096
Two years before current fiscal year | 225,376 | 182,487
Three years before current fiscal year | 173,280 | 64,511
Four years before current fiscal year | 58,729 | 69,366
Prior | 289,352 | 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 | 1,262,120 | 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 | 99,847 | 450,001
Fiscal year before current fiscal year | 414,595 | 226,038
Two years before current fiscal year | 217,451 | 172,208
Three years before current fiscal year | 165,209 | 63,906
Four years before current fiscal year | 58,286 | 61,929
Prior | 284,514 | 247,404
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,239,902 | 1,221,486
Commercial Industrial And Other Portfolio Segment | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 30 | 469
Fiscal year before current fiscal year | 591 | 640
Two years before current fiscal year | 7,628 | 10,095
Three years before current fiscal year | 7,984 | 570
Four years before current fiscal year | 436 | 7,280
Prior | 4,471 | 158
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 21,140 | 19,212
Commercial Industrial And Other Portfolio Segment | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 346
Fiscal year before current fiscal year | 320 | 418
Two years before current fiscal year | 297 | 184
Three years before current fiscal year | 87 | 35
Four years before current fiscal year | 7 | 157
Prior | 367 | 633
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,078 | 1,773
Consumer Loans |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 4,770 | 48,669
Fiscal year before current fiscal year | 39,288 | 21,352
Two years before current fiscal year | 16,366 | 12,105
Three years before current fiscal year | 9,131 | 8,011
Four years before current fiscal year | 0 | 2,002
Prior | 5,628 | 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 | 477 | 1,075
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 80,241 | 97,775
Current period gross writeoffs, total loans receivables | 627 | 1,380
Consumer Loans | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 4,768 | 48,600
Fiscal year before current fiscal year | 39,001 | 21,088
Two years before current fiscal year | 16,075 | 12,101
Three years before current fiscal year | 9,075 | 7,968
Four years before current fiscal year | 0 | 1,945
Prior | 5,556 | 5,630
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 79,498 | 97,332
Consumer Loans | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 0
Fiscal year before current fiscal year | 0 | 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 | 11 | 24
Consumer Loans | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 2 | 69
Fiscal year before current fiscal year | 276 | 246
Two years before current fiscal year | 291 | 3
Three years before current fiscal year | 56 | 43
Four years before current fiscal year | 35 | 52
Prior | 72 | 6
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 732 | 419
Real Estate Loan |  |
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 3,322,737 | 3,319,128
Real Estate Loan | Construction and Land Development |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 22,920 | 63,846
Fiscal year before current fiscal year | 76,473 | 39,790
Two years before current fiscal year | 19,722 | 12,558
Three years before current fiscal year | 6,004 | 15,801
Four years before current fiscal year | 15,785 | 1,210
Prior | 10,670 | 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 | 151,574 | 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 | 22,920 | 63,846
Fiscal year before current fiscal year | 76,473 | 39,790
Two years before current fiscal year | 19,722 | 12,558
Three years before current fiscal year | 6,004 | 15,787
Four years before current fiscal year | 15,785 | 1,210
Prior | 10,216 | 10,601
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 151,120 | 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 | 454 | 458
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 454 | 472
Real Estate Loan | Agricultural |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 5,197 | 172,956
Fiscal year before current fiscal year | 169,714 | 67,115
Two years before current fiscal year | 58,982 | 58,773
Three years before current fiscal year | 56,198 | 25,060
Four years before current fiscal year | 23,779 | 29,229
Prior | 78,350 | 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 | 392,220 | 410,327
Current period gross writeoffs, total loans receivables | 0 | 0
Real Estate Loan | Agricultural | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 5,197 | 171,833
Fiscal year before current fiscal year | 169,602 | 67,115
Two years before current fiscal year | 58,982 | 58,283
Three years before current fiscal year | 56,172 | 23,820
Four years before current fiscal year | 22,539 | 27,573
Prior | 74,908 | 52,799
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 387,400 | 401,423
Real Estate Loan | Agricultural | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 1,123
Fiscal year before current fiscal year | 112 | 0
Two years before current fiscal year | 0 | 490
Three years before current fiscal year | 26 | 1,240
Four years before current fiscal year | 1,240 | 273
Prior | 2,231 | 3,121
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 3,609 | 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 | 0 | 0
Three years before current fiscal year | 0 | 0
Four years before current fiscal year | 0 | 1,383
Prior | 1,211 | 1,274
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,211 | 2,657
Real Estate Loan | Commercial And Multifamily Portfolio Segment |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 86,685 | 564,891
Fiscal year before current fiscal year | 566,312 | 511,379
Two years before current fiscal year | 521,539 | 320,612
Three years before current fiscal year | 310,287 | 241,945
Four years before current fiscal year | 234,273 | 217,851
Prior | 640,915 | 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 | 2,360,011 | 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 | 86,685 | 558,921
Fiscal year before current fiscal year | 560,815 | 509,614
Two years before current fiscal year | 519,951 | 319,049
Three years before current fiscal year | 309,492 | 239,564
Four years before current fiscal year | 232,790 | 211,505
Prior | 626,080 | 453,076
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,335,813 | 2,291,729
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 2,187
Fiscal year before current fiscal year | 2,016 | 1,287
Two years before current fiscal year | 1,123 | 769
Three years before current fiscal year | 754 | 1,508
Four years before current fiscal year | 660 | 952
Prior | 6,498 | 8,503
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 11,051 | 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 | 3,481 | 478
Two years before current fiscal year | 465 | 794
Three years before current fiscal year | 41 | 873
Four years before current fiscal year | 823 | 5,394
Prior | 8,337 | 6,100
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 13,147 | 17,422
1-4 Family | Real Estate Loan |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 19,029 | 95,606
Fiscal year before current fiscal year | 85,560 | 87,501
Two years before current fiscal year | 82,935 | 79,507
Three years before current fiscal year | 72,887 | 27,919
Four years before current fiscal year | 24,606 | 33,796
Prior | 91,489 | 72,129
Revolving Loans | 42,426 | 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 | 42 | 111
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 418,932 | 440,180
Current period gross writeoffs, total loans receivables | 56 | 191
1-4 Family | Real Estate Loan | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 18,858 | 94,377
Fiscal year before current fiscal year | 84,398 | 86,717
Two years before current fiscal year | 82,341 | 78,977
Three years before current fiscal year | 72,373 | 27,580
Four years before current fiscal year | 24,307 | 30,809
Prior | 78,593 | 63,050
Revolving Loans | 42,426 | 43,722
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 403,296 | 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 | 184 | 218
Two years before current fiscal year | 116 | 1
Three years before current fiscal year | 0 | 44
Four years before current fiscal year | 0 | 238
Prior | 3,857 | 1,000
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 4,157 | 1,670
1-4 Family | Real Estate Loan | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 171 | 1,060
Fiscal year before current fiscal year | 978 | 566
Two years before current fiscal year | 478 | 529
Three years before current fiscal year | 514 | 295
Four years before current fiscal year | 299 | 2,749
Prior | 9,039 | 8,079
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | $ 11,479 | $ 13,278

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