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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, 2022 | Dec. 31, 2021
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Credit Quality Information [Abstract] |  |
Current fiscal year | $ 383,780 | $ 1,200,288
Fiscal year before current fiscal year | 1,216,168 | 818,943
Two years before current fiscal year | 793,781 | 547,593
Three years before current fiscal year | 532,798 | 374,575
Four years before current fiscal year | 393,170 | 247,554
Prior | 1,088,280 | 763,077
Revolving Loans | 46,584 | 43,493
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 4,454,561 | 3,995,523
Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 373,016 | 1,177,678
Fiscal year before current fiscal year | 1,202,200 | 815,269
Two years before current fiscal year | 790,036 | 527,037
Three years before current fiscal year | 519,908 | 367,606
Four years before current fiscal year | 381,784 | 225,557
Prior | 1,038,744 | 726,479
Revolving Loans | 45,912 | 42,800
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 4,351,600 | 3,882,426
Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 6,787 | 18,807
Fiscal year before current fiscal year | 12,413 | 2,354
Two years before current fiscal year | 2,012 | 11,947
Three years before current fiscal year | 11,623 | 2,519
Four years before current fiscal year | 3,765 | 13,769
Prior | 27,520 | 16,798
Revolving Loans | 40 | 41
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 64,160 | 66,235
Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 3,977 | 3,803
Fiscal year before current fiscal year | 1,555 | 1,320
Two years before current fiscal year | 1,733 | 8,609
Three years before current fiscal year | 1,267 | 4,450
Four years before current fiscal year | 7,621 | 8,228
Prior | 22,016 | 19,800
Revolving Loans | 632 | 652
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 38,801 | 46,862
Agricultural Loans |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 38,944 | 119,453
Fiscal year before current fiscal year | 58,801 | 18,357
Two years before current fiscal year | 12,206 | 8,260
Three years before current fiscal year | 7,167 | 2,972
Four years before current fiscal year | 2,459 | 937
Prior | 2,131 | 1,505
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 121,708 | 151,484
Agricultural Loans | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 35,055 | 105,378
Fiscal year before current fiscal year | 48,882 | 17,903
Two years before current fiscal year | 11,860 | 5,612
Three years before current fiscal year | 4,502 | 2,822
Four years before current fiscal year | 2,330 | 924
Prior | 2,067 | 1,316
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 104,696 | 133,955
Agricultural Loans | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 3,859 | 13,725
Fiscal year before current fiscal year | 9,913 | 436
Two years before current fiscal year | 346 | 2,648
Three years before current fiscal year | 2,648 | 150
Four years before current fiscal year | 129 | 13
Prior | 64 | 64
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 16,959 | 17,036
Agricultural Loans | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 30 | 350
Fiscal year before current fiscal year | 6 | 18
Two years before current fiscal year | 0 | 0
Three years before current fiscal year | 17 | 0
Four years before current fiscal year | 0 | 0
Prior | 0 | 125
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 53 | 493
Commercial Industrial And Other Portfolio Segment |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 117,051 | 280,933
Fiscal year before current fiscal year | 327,472 | 168,095
Two years before current fiscal year | 149,849 | 121,298
Three years before current fiscal year | 90,651 | 76,825
Four years before current fiscal year | 58,815 | 23,389
Prior | 294,460 | 305,214
Revolving Loans | 39,894 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,078,192 | 975,754
Commercial Industrial And Other Portfolio Segment | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 116,681 | 279,814
Fiscal year before current fiscal year | 326,191 | 167,662
Two years before current fiscal year | 149,215 | 119,702
Three years before current fiscal year | 88,980 | 76,022
Four years before current fiscal year | 58,513 | 22,888
Prior | 292,322 | 302,962
Revolving Loans | 39,894 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,071,796 | 969,050
Commercial Industrial And Other Portfolio Segment | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 370 | 613
Fiscal year before current fiscal year | 694 | 399
Two years before current fiscal year | 274 | 1,463
Three years before current fiscal year | 1,639 | 182
Four years before current fiscal year | 174 | 477
Prior | 1,023 | 819
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 4,174 | 3,953
Commercial Industrial And Other Portfolio Segment | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 506
Fiscal year before current fiscal year | 587 | 34
Two years before current fiscal year | 360 | 133
Three years before current fiscal year | 32 | 621
Four years before current fiscal year | 128 | 24
Prior | 1,115 | 1,433
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,222 | 2,751
Consumer Loans |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 11,327 | 28,601
Fiscal year before current fiscal year | 29,516 | 19,145
Two years before current fiscal year | 19,319 | 17,324
Three years before current fiscal year | 16,541 | 6,192
Four years before current fiscal year | 5,116 | 4,340
Prior | 5,391 | 2,840
Revolving Loans | 2,475 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 89,685 | 78,442
Consumer Loans | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 11,315 | 27,948
Fiscal year before current fiscal year | 29,356 | 19,033
Two years before current fiscal year | 19,264 | 16,978
Three years before current fiscal year | 16,484 | 5,505
Four years before current fiscal year | 5,049 | 4,297
Prior | 5,321 | 1,244
Revolving Loans | 2,475 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 89,264 | 75,005
Consumer Loans | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 68
Fiscal year before current fiscal year | 64 | 54
Two years before current fiscal year | 32 | 38
Three years before current fiscal year | 35 | 9
Four years before current fiscal year | 8 | 0
Prior | 0 | 0
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 139 | 169
Consumer Loans | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 12 | 585
Fiscal year before current fiscal year | 96 | 58
Two years before current fiscal year | 23 | 308
Three years before current fiscal year | 22 | 678
Four years before current fiscal year | 59 | 43
Prior | 70 | 1,596
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 282 | 3,268
Real Estate Loan |  |
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 3,164,976 | 2,789,843
Real Estate Loan | Construction and Land Development |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 7,333 | 38,766
Fiscal year before current fiscal year | 47,327 | 34,774
Two years before current fiscal year | 33,352 | 23,505
Three years before current fiscal year | 26,873 | 34,841
Four years before current fiscal year | 2,599 | 3,760
Prior | 14,020 | 9,472
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 131,504 | 145,118
Real Estate Loan | Construction and Land Development | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 7,333 | 38,656
Fiscal year before current fiscal year | 47,220 | 34,774
Two years before current fiscal year | 33,352 | 23,505
Three years before current fiscal year | 26,873 | 34,358
Four years before current fiscal year | 2,599 | 3,760
Prior | 13,533 | 9,433
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 130,910 | 144,486
Real Estate Loan | Construction and Land Development | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 110
Fiscal year before current fiscal year | 107 | 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 | 107 | 110
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 | 483
Four years before current fiscal year | 0 | 0
Prior | 487 | 39
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 487 | 522
Real Estate Loan | Agricultural |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 28,821 | 79,665
Fiscal year before current fiscal year | 91,953 | 64,418
Two years before current fiscal year | 65,248 | 30,133
Three years before current fiscal year | 30,171 | 30,774
Four years before current fiscal year | 39,952 | 12,268
Prior | 24,421 | 62,014
Revolving Loans | 427 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 280,993 | 279,272
Real Estate Loan | Agricultural | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 27,996 | 78,793
Fiscal year before current fiscal year | 91,907 | 64,159
Two years before current fiscal year | 64,989 | 25,713
Three years before current fiscal year | 26,672 | 30,203
Four years before current fiscal year | 39,318 | 12,142
Prior | 18,288 | 54,808
Revolving Loans | 427 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 269,597 | 265,818
Real Estate Loan | Agricultural | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 825 | 872
Fiscal year before current fiscal year | 46 | 259
Two years before current fiscal year | 259 | 4,028
Three years before current fiscal year | 3,499 | 384
Four years before current fiscal year | 390 | 69
Prior | 5,504 | 6,087
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 10,523 | 11,699
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 | 392
Three years before current fiscal year | 0 | 187
Four years before current fiscal year | 244 | 57
Prior | 629 | 1,119
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 873 | 1,755
Real Estate Loan | Commercial And Multifamily Portfolio Segment |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 163,182 | 573,392
Fiscal year before current fiscal year | 565,280 | 419,254
Two years before current fiscal year | 411,723 | 308,051
Three years before current fiscal year | 320,324 | 176,922
Four years before current fiscal year | 231,838 | 166,066
Prior | 642,682 | 321,455
Revolving Loans | 218 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,335,247 | 1,965,140
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 157,560 | 568,200
Fiscal year before current fiscal year | 563,350 | 417,334
Two years before current fiscal year | 409,771 | 299,973
Three years before current fiscal year | 317,733 | 174,448
Four years before current fiscal year | 224,746 | 150,811
Prior | 614,381 | 304,585
Revolving Loans | 218 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,287,759 | 1,915,351
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 1,733 | 3,185
Fiscal year before current fiscal year | 1,431 | 1,206
Two years before current fiscal year | 1,101 | 1,836
Three years before current fiscal year | 1,887 | 1,295
Four years before current fiscal year | 1,268 | 10,609
Prior | 17,831 | 8,632
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 25,251 | 26,763
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 3,889 | 2,007
Fiscal year before current fiscal year | 499 | 714
Two years before current fiscal year | 851 | 6,242
Three years before current fiscal year | 704 | 1,179
Four years before current fiscal year | 5,824 | 4,646
Prior | 10,470 | 8,238
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 22,237 | 23,026
1-4 Family | Real Estate Loan |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 17,122 | 79,478
Fiscal year before current fiscal year | 95,819 | 94,900
Two years before current fiscal year | 102,084 | 39,022
Three years before current fiscal year | 41,071 | 46,049
Four years before current fiscal year | 52,391 | 36,794
Prior | 105,175 | 60,577
Revolving Loans | 3,570 | 43,493
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 417,232 | 400,313
1-4 Family | Real Estate Loan | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 17,076 | 78,889
Fiscal year before current fiscal year | 95,294 | 94,404
Two years before current fiscal year | 101,585 | 35,554
Three years before current fiscal year | 38,664 | 44,248
Four years before current fiscal year | 49,229 | 30,735
Prior | 92,832 | 52,131
Revolving Loans | 2,898 | 42,800
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 397,578 | 378,761
1-4 Family | Real Estate Loan | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 234
Fiscal year before current fiscal year | 158 | 0
Two years before current fiscal year | 0 | 1,934
Three years before current fiscal year | 1,915 | 499
Four years before current fiscal year | 1,796 | 2,601
Prior | 3,098 | 1,196
Revolving Loans | 40 | 41
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 7,007 | 6,505
1-4 Family | Real Estate Loan | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 46 | 355
Fiscal year before current fiscal year | 367 | 496
Two years before current fiscal year | 499 | 1,534
Three years before current fiscal year | 492 | 1,302
Four years before current fiscal year | 1,366 | 3,458
Prior | 9,245 | 7,250
Revolving Loans | 632 | 652
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | $ 12,647 | $ 15,047

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