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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, 2023 | Dec. 31, 2022
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Credit Quality Information [Abstract] |  |
Current fiscal year | $ 134,451 | $ 1,535,342
Fiscal year before current fiscal year | 1,444,312 | 973,016
Two years before current fiscal year | 941,949 | 669,475
Three years before current fiscal year | 648,881 | 387,967
Four years before current fiscal year | 374,911 | 354,435
Prior | 1,174,067 | 862,255
Revolving Loans | 42,060 | 43,722
Current period gross writeoffs, current fiscal year | 0 | 311
Current period gross writeoffs, fiscal year before current fiscal year | 50 | 603
Current period gross writeoffs, two year before current fiscal year | 61 | 195
Current period gross writeoffs, three year before current fiscal year | 1 | 462
Current period gross writeoffs, four year before current fiscal year | 9 | 30
Current period gross writeoffs, prior | 359 | 1,349
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 4,760,631 | 4,826,212
Current period gross writeoffs, total loans receivables | 480 | 2,950
Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 134,327 | 1,524,905
Fiscal year before current fiscal year | 1,435,092 | 969,145
Two years before current fiscal year | 931,043 | 656,609
Three years before current fiscal year | 639,336 | 382,543
Four years before current fiscal year | 370,452 | 335,886
Prior | 1,131,368 | 832,814
Revolving Loans | 42,060 | 43,722
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 4,683,678 | 4,745,624
Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 71 | 5,126
Fiscal year before current fiscal year | 3,614 | 2,163
Two years before current fiscal year | 9,201 | 11,356
Three years before current fiscal year | 8,772 | 4,118
Four years before current fiscal year | 3,225 | 8,814
Prior | 22,139 | 12,891
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 47,022 | 44,468
Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 53 | 5,311
Fiscal year before current fiscal year | 5,606 | 1,708
Two years before current fiscal year | 1,705 | 1,510
Three years before current fiscal year | 773 | 1,306
Four years before current fiscal year | 1,234 | 9,735
Prior | 20,560 | 16,550
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 29,931 | 36,120
Agricultural Loans |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 39,086 | 138,558
Fiscal year before current fiscal year | 80,041 | 18,783
Two years before current fiscal year | 18,754 | 3,433
Three years before current fiscal year | 4,669 | 4,720
Four years before current fiscal year | 2,263 | 981
Prior | 2,034 | 363
Revolving Loans | 0 | 0
Current period gross writeoffs, current fiscal year | 0 | 0
Current period gross writeoffs, fiscal year before current fiscal year | 0 | 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 | 146,847 | 166,838
Current period gross writeoffs, total loans receivables | 0 | 93
Agricultural Loans | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 39,064 | 137,327
Fiscal year before current fiscal year | 78,918 | 18,783
Two years before current fiscal year | 18,652 | 3,433
Three years before current fiscal year | 4,669 | 3,918
Four years before current fiscal year | 2,184 | 915
Prior | 1,969 | 254
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 145,456 | 164,630
Agricultural Loans | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 22 | 1,178
Fiscal year before current fiscal year | 744 | 0
Two years before current fiscal year | 0 | 0
Three years before current fiscal year | 0 | 756
Four years before current fiscal year | 74 | 66
Prior | 65 | 109
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 905 | 2,109
Agricultural Loans | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 53
Fiscal year before current fiscal year | 379 | 0
Two years before current fiscal year | 102 | 0
Three years before current fiscal year | 0 | 46
Four years before current fiscal year | 5 | 0
Prior | 0 | 0
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 486 | 99
Commercial Industrial And Other Portfolio Segment |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 60,725 | 450,816
Fiscal year before current fiscal year | 424,326 | 227,096
Two years before current fiscal year | 216,303 | 182,487
Three years before current fiscal year | 177,780 | 64,511
Four years before current fiscal year | 61,727 | 69,366
Prior | 293,379 | 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 | 0 | 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 | 1,234,240 | 1,242,471
Current period gross writeoffs, total loans receivables | 13 | 870
Commercial Industrial And Other Portfolio Segment | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 60,676 | 450,001
Fiscal year before current fiscal year | 423,532 | 226,038
Two years before current fiscal year | 208,003 | 172,208
Three years before current fiscal year | 169,864 | 63,906
Four years before current fiscal year | 61,133 | 61,929
Prior | 286,309 | 247,404
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,209,517 | 1,221,486
Commercial Industrial And Other Portfolio Segment | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 49 | 469
Fiscal year before current fiscal year | 409 | 640
Two years before current fiscal year | 7,972 | 10,095
Three years before current fiscal year | 7,760 | 570
Four years before current fiscal year | 587 | 7,280
Prior | 6,470 | 158
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 23,247 | 19,212
Commercial Industrial And Other Portfolio Segment | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 346
Fiscal year before current fiscal year | 385 | 418
Two years before current fiscal year | 328 | 184
Three years before current fiscal year | 156 | 35
Four years before current fiscal year | 7 | 157
Prior | 600 | 633
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,476 | 1,773
Consumer Loans |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 2,436 | 48,669
Fiscal year before current fiscal year | 43,465 | 21,352
Two years before current fiscal year | 18,934 | 12,105
Three years before current fiscal year | 10,523 | 8,011
Four years before current fiscal year | 6,056 | 2,002
Prior | 7,016 | 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 | 50 | 177
Current period gross writeoffs, two year before current fiscal year | 61 | 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 | 306 | 1,075
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 88,430 | 97,775
Current period gross writeoffs, total loans receivables | 427 | 1,380
Consumer Loans | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 2,434 | 48,600
Fiscal year before current fiscal year | 43,310 | 21,088
Two years before current fiscal year | 18,614 | 12,101
Three years before current fiscal year | 10,484 | 7,968
Four years before current fiscal year | 6,019 | 1,945
Prior | 6,964 | 5,630
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 87,825 | 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 | 17 | 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 | 17 | 24
Consumer Loans | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 2 | 69
Fiscal year before current fiscal year | 155 | 246
Two years before current fiscal year | 303 | 3
Three years before current fiscal year | 39 | 43
Four years before current fiscal year | 37 | 52
Prior | 52 | 6
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 588 | 419
Real Estate Loan |  |
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 3,291,114 | 3,319,128
Real Estate Loan | Construction and Land Development |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 9,251 | 63,846
Fiscal year before current fiscal year | 79,695 | 39,790
Two years before current fiscal year | 35,078 | 12,558
Three years before current fiscal year | 7,325 | 15,801
Four years before current fiscal year | 15,878 | 1,210
Prior | 11,930 | 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 | 0 | 2
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 159,157 | 144,264
Current period gross writeoffs, total loans receivables | 0 | 2
Real Estate Loan | Construction and Land Development | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 9,251 | 63,846
Fiscal year before current fiscal year | 79,695 | 39,790
Two years before current fiscal year | 35,078 | 12,558
Three years before current fiscal year | 7,325 | 15,787
Four years before current fiscal year | 15,864 | 1,210
Prior | 11,465 | 10,601
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 158,678 | 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 | 14 | 0
Prior | 465 | 458
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 479 | 472
Real Estate Loan | Agricultural |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 3,716 | 172,956
Fiscal year before current fiscal year | 167,494 | 67,115
Two years before current fiscal year | 64,522 | 58,773
Three years before current fiscal year | 57,417 | 25,060
Four years before current fiscal year | 23,971 | 29,229
Prior | 84,837 | 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 | 401,957 | 410,327
Current period gross writeoffs, total loans receivables | 0 | 0
Real Estate Loan | Agricultural | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 3,716 | 171,833
Fiscal year before current fiscal year | 167,382 | 67,115
Two years before current fiscal year | 64,522 | 58,283
Three years before current fiscal year | 57,166 | 23,820
Four years before current fiscal year | 22,731 | 27,573
Prior | 80,117 | 52,799
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 395,634 | 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 | 251 | 1,240
Four years before current fiscal year | 1,240 | 273
Prior | 3,499 | 3,121
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 5,102 | 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 | 1,221 | 1,274
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,221 | 2,657
Real Estate Loan | Commercial And Multifamily Portfolio Segment |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 11,117 | 564,891
Fiscal year before current fiscal year | 561,423 | 511,379
Two years before current fiscal year | 504,156 | 320,612
Three years before current fiscal year | 315,277 | 241,945
Four years before current fiscal year | 237,938 | 217,851
Prior | 675,544 | 467,679
Revolving Loans | 0 | 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 | 2,305,455 | 2,324,357
Current period gross writeoffs, total loans receivables | 0 | 414
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 11,117 | 558,921
Fiscal year before current fiscal year | 555,543 | 509,614
Two years before current fiscal year | 502,596 | 319,049
Three years before current fiscal year | 314,461 | 239,564
Four years before current fiscal year | 235,766 | 211,505
Prior | 658,790 | 453,076
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,278,273 | 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 | 2,163 | 1,287
Two years before current fiscal year | 1,089 | 769
Three years before current fiscal year | 761 | 1,508
Four years before current fiscal year | 1,281 | 952
Prior | 7,933 | 8,503
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 13,227 | 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 | 3,717 | 478
Two years before current fiscal year | 471 | 794
Three years before current fiscal year | 55 | 873
Four years before current fiscal year | 891 | 5,394
Prior | 8,821 | 6,100
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 13,955 | 17,422
1-4 Family | Real Estate Loan |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 8,120 | 95,606
Fiscal year before current fiscal year | 87,868 | 87,501
Two years before current fiscal year | 84,202 | 79,507
Three years before current fiscal year | 75,890 | 27,919
Four years before current fiscal year | 27,078 | 33,796
Prior | 99,327 | 72,129
Revolving Loans | 42,060 | 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 | 0 | 0
Current period gross writeoffs, prior | 40 | 111
Current period gross writeoffs, revolving loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 424,545 | 440,180
Current period gross writeoffs, total loans receivables | 40 | 191
1-4 Family | Real Estate Loan | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 8,069 | 94,377
Fiscal year before current fiscal year | 86,712 | 86,717
Two years before current fiscal year | 83,578 | 78,977
Three years before current fiscal year | 75,367 | 27,580
Four years before current fiscal year | 26,755 | 30,809
Prior | 85,754 | 63,050
Revolving Loans | 42,060 | 43,722
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 408,295 | 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 | 186 | 218
Two years before current fiscal year | 123 | 1
Three years before current fiscal year | 0 | 44
Four years before current fiscal year | 43 | 238
Prior | 4,172 | 1,000
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 4,524 | 1,670
1-4 Family | Real Estate Loan | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 51 | 1,060
Fiscal year before current fiscal year | 970 | 566
Two years before current fiscal year | 501 | 529
Three years before current fiscal year | 523 | 295
Four years before current fiscal year | 280 | 2,749
Prior | 9,401 | 8,079
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | $ 11,726 | $ 13,278

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