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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, 2024 | Dec. 31, 2023
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Credit Quality Information [Abstract] |  |
Current fiscal year | $ 355,444 | $ 792,071
Fiscal year before current fiscal year | 721,318 | 1,402,051
Two years before current fiscal year | 1,343,501 | 994,108
Three years before current fiscal year | 978,481 | 619,354
Four years before current fiscal year | 595,314 | 381,174
Prior | 1,492,655 | 1,315,596
Revolving Loans | 73,904 | 76,211
Current period gross writeoffs, current fiscal year | 0 | 10
Current period gross writeoffs, fiscal year before current fiscal year | 165 | 761
Current period gross writeoffs, two year before current fiscal year | 413 | 208
Current period gross writeoffs, three year before current fiscal year | 543 | 51
Current period gross writeoffs, four year before current fiscal year | 30 | 93
Current period gross writeoffs, prior | 653 | 1,508
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 5,560,617 | 5,580,565
Current period gross writeoffs, total loans receivables | 1,804 | 2,631
Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 353,129 | 786,908
Fiscal year before current fiscal year | 719,798 | 1,390,885
Two years before current fiscal year | 1,334,374 | 976,531
Three years before current fiscal year | 968,401 | 616,020
Four years before current fiscal year | 592,600 | 376,655
Prior | 1,461,143 | 1,254,871
Revolving Loans | 72,811 | 75,700
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 5,502,256 | 5,477,570
Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 2,171 | 4,925
Fiscal year before current fiscal year | 1,233 | 5,566
Two years before current fiscal year | 4,079 | 15,110
Three years before current fiscal year | 8,383 | 2,721
Four years before current fiscal year | 1,721 | 3,368
Prior | 13,180 | 42,350
Revolving Loans | 0 | 10
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 30,767 | 74,050
Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 144 | 238
Fiscal year before current fiscal year | 287 | 5,600
Two years before current fiscal year | 5,048 | 2,467
Three years before current fiscal year | 1,697 | 613
Four years before current fiscal year | 993 | 1,151
Prior | 18,332 | 18,375
Revolving Loans | 1,093 | 501
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 27,594 | 28,945
Agricultural Loans |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 80,821 | 147,999
Fiscal year before current fiscal year | 83,731 | 27,905
Two years before current fiscal year | 27,360 | 10,044
Three years before current fiscal year | 16,109 | 2,549
Four years before current fiscal year | 3,202 | 1,921
Prior | 2,774 | 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 | 213,997 | 196,272
Current period gross writeoffs, total loans receivables | 261 | 408
Agricultural Loans | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 80,406 | 147,993
Fiscal year before current fiscal year | 83,720 | 27,895
Two years before current fiscal year | 27,310 | 10,044
Three years before current fiscal year | 16,109 | 2,549
Four years before current fiscal year | 3,202 | 1,883
Prior | 2,387 | 5,854
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 213,134 | 196,218
Agricultural Loans | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 415 | 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 | 371 | 0
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 797 | 54
Agricultural Loans | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 0
Fiscal year before current fiscal year | 0 | 0
Two years before current fiscal year | 50 | 0
Three years before current fiscal year | 0 | 0
Four years before current fiscal year | 0 | 0
Prior | 16 | 0
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 66 | 0
Commercial Industrial And Other Portfolio Segment |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 124,679 | 291,351
Fiscal year before current fiscal year | 269,155 | 309,188
Two years before current fiscal year | 285,454 | 242,971
Three years before current fiscal year | 228,045 | 155,119
Four years before current fiscal year | 144,241 | 74,532
Prior | 392,883 | 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 | 206 | 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 | 1,444,457 | 1,450,768
Current period gross writeoffs, total loans receivables | 642 | 529
Commercial Industrial And Other Portfolio Segment | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 124,458 | 290,304
Fiscal year before current fiscal year | 268,023 | 306,794
Two years before current fiscal year | 284,063 | 232,198
Three years before current fiscal year | 221,470 | 154,499
Four years before current fiscal year | 142,785 | 73,906
Prior | 389,153 | 347,957
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,429,952 | 1,405,658
Commercial Industrial And Other Portfolio Segment | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 221 | 1,047
Fiscal year before current fiscal year | 1,023 | 1,857
Two years before current fiscal year | 1,190 | 9,982
Three years before current fiscal year | 6,365 | 562
Four years before current fiscal year | 1,426 | 597
Prior | 3,077 | 28,900
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 13,302 | 42,945
Commercial Industrial And Other Portfolio Segment | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 0
Fiscal year before current fiscal year | 109 | 537
Two years before current fiscal year | 201 | 791
Three years before current fiscal year | 210 | 58
Four years before current fiscal year | 30 | 29
Prior | 653 | 750
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,203 | 2,165
Consumer Loans |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 3,310 | 9,633
Fiscal year before current fiscal year | 7,017 | 40,656
Two years before current fiscal year | 32,191 | 21,589
Three years before current fiscal year | 15,705 | 10,526
Four years before current fiscal year | 7,002 | 4,534
Prior | 5,616 | 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 | 18 | 177
Current period gross writeoffs, two year before current fiscal year | 97 | 89
Current period gross writeoffs, three year before current fiscal year | 113 | 10
Current period gross writeoffs, four year before current fiscal year | 20 | 7
Current period gross writeoffs, prior | 552 | 1,075
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 70,841 | 91,014
Current period gross writeoffs, total loans receivables | 800 | 1,380
Consumer Loans | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 3,310 | 9,547
Fiscal year before current fiscal year | 6,963 | 40,225
Two years before current fiscal year | 31,916 | 21,264
Three years before current fiscal year | 15,509 | 10,387
Four years before current fiscal year | 6,876 | 4,475
Prior | 5,572 | 4,035
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 70,146 | 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 | 20 | 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 | 20 | 26
Consumer Loans | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 86
Fiscal year before current fiscal year | 54 | 405
Two years before current fiscal year | 255 | 325
Three years before current fiscal year | 196 | 139
Four years before current fiscal year | 126 | 59
Prior | 44 | 41
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 675 | 1,055
Real Estate Loan |  |
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 3,831,322 | 3,842,511
Real Estate Loan | Construction and Land Development |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 25,088 | 68,086
Fiscal year before current fiscal year | 97,041 | 74,065
Two years before current fiscal year | 28,802 | 27,392
Three years before current fiscal year | 16,349 | 5,188
Four years before current fiscal year | 5,124 | 10,795
Prior | 22,985 | 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 | 195,389 | 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 | 25,088 | 68,086
Fiscal year before current fiscal year | 97,041 | 74,065
Two years before current fiscal year | 28,796 | 27,392
Three years before current fiscal year | 16,349 | 5,188
Four years before current fiscal year | 5,124 | 10,795
Prior | 22,568 | 19,115
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 194,966 | 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 | 401 | 0
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 401 | 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 | 16 | 436
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 22 | 436
Real Estate Loan | Agricultural |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 14,559 | 19,437
Fiscal year before current fiscal year | 18,677 | 164,812
Two years before current fiscal year | 161,004 | 58,813
Three years before current fiscal year | 56,176 | 53,249
Four years before current fiscal year | 51,641 | 20,589
Prior | 84,958 | 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 | 387,015 | 391,132
Current period gross writeoffs, total loans receivables | 0 | 0
Real Estate Loan | Agricultural | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 13,389 | 19,231
Fiscal year before current fiscal year | 18,478 | 164,812
Two years before current fiscal year | 161,004 | 57,815
Three years before current fiscal year | 55,184 | 53,249
Four years before current fiscal year | 51,641 | 19,419
Prior | 82,032 | 71,189
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 381,728 | 385,715
Real Estate Loan | Agricultural | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 1,170 | 206
Fiscal year before current fiscal year | 199 | 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 | 3,861 | 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 | 364 | 0
Four years before current fiscal year | 0 | 0
Prior | 1,062 | 1,175
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,426 | 1,546
Real Estate Loan | Commercial And Multifamily Portfolio Segment |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 81,514 | 189,294
Fiscal year before current fiscal year | 204,555 | 686,704
Two years before current fiscal year | 729,451 | 550,570
Three years before current fiscal year | 562,811 | 319,254
Four years before current fiscal year | 315,151 | 241,661
Prior | 847,919 | 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 | 2,741,401 | 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 | 81,149 | 185,628
Fiscal year before current fiscal year | 204,555 | 680,099
Two years before current fiscal year | 723,001 | 548,733
Three years before current fiscal year | 561,064 | 317,075
Four years before current fiscal year | 314,856 | 239,323
Prior | 832,804 | 701,464
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,717,429 | 2,672,322
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 365 | 3,666
Fiscal year before current fiscal year | 0 | 2,706
Two years before current fiscal year | 2,657 | 1,317
Three years before current fiscal year | 1,313 | 2,159
Four years before current fiscal year | 295 | 1,563
Prior | 6,887 | 7,778
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 11,517 | 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 | 3,793 | 520
Three years before current fiscal year | 434 | 20
Four years before current fiscal year | 0 | 775
Prior | 8,228 | 7,108
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 12,455 | 12,322
1-4 Family | Real Estate Loan |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 25,473 | 66,271
Fiscal year before current fiscal year | 41,142 | 98,721
Two years before current fiscal year | 79,239 | 82,729
Three years before current fiscal year | 83,286 | 73,469
Four years before current fiscal year | 68,953 | 27,142
Prior | 135,520 | 117,926
Revolving Loans | 73,904 | 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 | 55 | 63
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 507,517 | 542,469
Current period gross writeoffs, total loans receivables | 101 | 87
1-4 Family | Real Estate Loan | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 25,329 | 66,119
Fiscal year before current fiscal year | 41,018 | 96,995
Two years before current fiscal year | 78,284 | 79,085
Three years before current fiscal year | 82,716 | 73,073
Four years before current fiscal year | 68,116 | 26,854
Prior | 126,627 | 105,257
Revolving Loans | 72,811 | 75,700
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 494,901 | 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 | 212 | 3,184
Three years before current fiscal year | 77 | 0
Four years before current fiscal year | 0 | 0
Prior | 580 | 3,804
Revolving Loans | 0 | 10
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 869 | 7,965
1-4 Family | Real Estate Loan | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 144 | 152
Fiscal year before current fiscal year | 124 | 759
Two years before current fiscal year | 743 | 460
Three years before current fiscal year | 493 | 396
Four years before current fiscal year | 837 | 288
Prior | 8,313 | 8,865
Revolving Loans | 1,093 | 501
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | $ 11,747 | $ 11,421

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