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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, 2022 | Dec. 31, 2021
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Credit Quality Information [Abstract] |  |
Current fiscal year | $ 875,249 | $ 1,200,288
Fiscal year before current fiscal year | 1,143,527 | 818,943
Two years before current fiscal year | 729,809 | 547,593
Three years before current fiscal year | 469,495 | 374,575
Four years before current fiscal year | 382,009 | 247,554
Prior | 1,001,047 | 763,077
Revolving Loans | 47,527 | 43,493
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 4,648,663 | 3,995,523
Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 865,554 | 1,177,678
Fiscal year before current fiscal year | 1,138,255 | 815,269
Two years before current fiscal year | 726,036 | 527,037
Three years before current fiscal year | 461,044 | 367,606
Four years before current fiscal year | 370,010 | 225,557
Prior | 960,750 | 726,479
Revolving Loans | 47,094 | 42,800
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 4,568,743 | 3,882,426
Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 4,316 | 18,807
Fiscal year before current fiscal year | 3,568 | 2,354
Two years before current fiscal year | 2,134 | 11,947
Three years before current fiscal year | 6,985 | 2,519
Four years before current fiscal year | 1,801 | 13,769
Prior | 19,991 | 16,798
Revolving Loans | 129 | 41
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 38,924 | 66,235
Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 5,379 | 3,803
Fiscal year before current fiscal year | 1,404 | 1,320
Two years before current fiscal year | 1,639 | 8,609
Three years before current fiscal year | 1,466 | 4,450
Four years before current fiscal year | 10,198 | 8,228
Prior | 20,306 | 19,800
Revolving Loans | 304 | 652
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 40,696 | 46,862
Doubtful |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 |
Fiscal year before current fiscal year | 300 |
Two years before current fiscal year | 0 |
Three years before current fiscal year | 0 |
Four years before current fiscal year | 0 |
Prior | 0 |
Revolving Loans | 0 |
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 300 |
Agricultural Loans |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 85,742 | 119,453
Fiscal year before current fiscal year | 38,403 | 18,357
Two years before current fiscal year | 10,637 | 8,260
Three years before current fiscal year | 4,318 | 2,972
Four years before current fiscal year | 1,850 | 937
Prior | 1,456 | 1,505
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 142,406 | 151,484
Agricultural Loans | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 83,601 | 105,378
Fiscal year before current fiscal year | 37,086 | 17,903
Two years before current fiscal year | 10,637 | 5,612
Three years before current fiscal year | 4,013 | 2,822
Four years before current fiscal year | 1,765 | 924
Prior | 1,288 | 1,316
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 138,390 | 133,955
Agricultural Loans | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 1,201 | 13,725
Fiscal year before current fiscal year | 1,317 | 436
Two years before current fiscal year | 0 | 2,648
Three years before current fiscal year | 262 | 150
Four years before current fiscal year | 81 | 13
Prior | 0 | 64
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,861 | 17,036
Agricultural Loans | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 940 | 350
Fiscal year before current fiscal year | 0 | 18
Two years before current fiscal year | 0 | 0
Three years before current fiscal year | 43 | 0
Four years before current fiscal year | 4 | 0
Prior | 168 | 125
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,155 | 493
Commercial Industrial And Other Portfolio Segment |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 228,125 | 280,933
Fiscal year before current fiscal year | 320,815 | 168,095
Two years before current fiscal year | 185,599 | 121,298
Three years before current fiscal year | 79,245 | 76,825
Four years before current fiscal year | 77,545 | 23,389
Prior | 297,385 | 305,214
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,188,714 | 975,754
Commercial Industrial And Other Portfolio Segment | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 227,589 | 279,814
Fiscal year before current fiscal year | 319,582 | 167,662
Two years before current fiscal year | 184,910 | 119,702
Three years before current fiscal year | 77,852 | 76,022
Four years before current fiscal year | 77,171 | 22,888
Prior | 296,278 | 302,962
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,183,382 | 969,050
Commercial Industrial And Other Portfolio Segment | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 229 | 613
Fiscal year before current fiscal year | 478 | 399
Two years before current fiscal year | 322 | 1,463
Three years before current fiscal year | 1,353 | 182
Four years before current fiscal year | 265 | 477
Prior | 382 | 819
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 3,029 | 3,953
Commercial Industrial And Other Portfolio Segment | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 307 | 506
Fiscal year before current fiscal year | 455 | 34
Two years before current fiscal year | 367 | 133
Three years before current fiscal year | 40 | 621
Four years before current fiscal year | 109 | 24
Prior | 725 | 1,433
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,003 | 2,751
Commercial Industrial And Other Portfolio Segment | Doubtful |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 |
Fiscal year before current fiscal year | 300 |
Two years before current fiscal year | 0 |
Three years before current fiscal year | 0 |
Four years before current fiscal year | 0 |
Prior | 0 |
Revolving Loans | 0 |
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 300 |
Consumer Loans |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 28,830 | 28,601
Fiscal year before current fiscal year | 25,970 | 19,145
Two years before current fiscal year | 20,627 | 17,324
Three years before current fiscal year | 11,562 | 6,192
Four years before current fiscal year | 3,481 | 4,340
Prior | 4,358 | 2,840
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 94,828 | 78,442
Consumer Loans | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 28,818 | 27,948
Fiscal year before current fiscal year | 25,791 | 19,033
Two years before current fiscal year | 20,595 | 16,978
Three years before current fiscal year | 11,516 | 5,505
Four years before current fiscal year | 3,428 | 4,297
Prior | 4,328 | 1,244
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 94,476 | 75,005
Consumer Loans | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 0 | 68
Fiscal year before current fiscal year | 60 | 54
Two years before current fiscal year | 30 | 38
Three years before current fiscal year | 32 | 9
Four years before current fiscal year | 7 | 0
Prior | 0 | 0
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 129 | 169
Consumer Loans | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 12 | 585
Fiscal year before current fiscal year | 119 | 58
Two years before current fiscal year | 2 | 308
Three years before current fiscal year | 14 | 678
Four years before current fiscal year | 46 | 43
Prior | 30 | 1,596
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 223 | 3,268
Real Estate Loan |  |
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 3,222,715 | 2,789,843
Real Estate Loan | Construction and Land Development |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 24,090 | 38,766
Fiscal year before current fiscal year | 50,440 | 34,774
Two years before current fiscal year | 24,406 | 23,505
Three years before current fiscal year | 27,088 | 34,841
Four years before current fiscal year | 2,276 | 3,760
Prior | 12,772 | 9,472
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 141,072 | 145,118
Real Estate Loan | Construction and Land Development | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 24,090 | 38,656
Fiscal year before current fiscal year | 50,335 | 34,774
Two years before current fiscal year | 24,406 | 23,505
Three years before current fiscal year | 27,088 | 34,358
Four years before current fiscal year | 2,276 | 3,760
Prior | 12,294 | 9,433
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 140,489 | 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 | 105 | 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 | 105 | 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 | 478 | 39
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 478 | 522
Real Estate Loan | Agricultural |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 97,623 | 79,665
Fiscal year before current fiscal year | 73,365 | 64,418
Two years before current fiscal year | 59,661 | 30,133
Three years before current fiscal year | 26,721 | 30,774
Four years before current fiscal year | 29,838 | 12,268
Prior | 62,951 | 62,014
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 350,159 | 279,272
Real Estate Loan | Agricultural | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 96,798 | 78,793
Fiscal year before current fiscal year | 73,365 | 64,159
Two years before current fiscal year | 59,171 | 25,713
Three years before current fiscal year | 23,222 | 30,203
Four years before current fiscal year | 28,105 | 12,142
Prior | 58,227 | 54,808
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 338,888 | 265,818
Real Estate Loan | Agricultural | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 825 | 872
Fiscal year before current fiscal year | 0 | 259
Two years before current fiscal year | 490 | 4,028
Three years before current fiscal year | 3,499 | 384
Four years before current fiscal year | 273 | 69
Prior | 3,248 | 6,087
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 8,335 | 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 | 1,460 | 57
Prior | 1,476 | 1,119
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,936 | 1,755
Real Estate Loan | Commercial And Multifamily Portfolio Segment |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 365,250 | 573,392
Fiscal year before current fiscal year | 540,868 | 419,254
Two years before current fiscal year | 343,019 | 308,051
Three years before current fiscal year | 290,075 | 176,922
Four years before current fiscal year | 229,921 | 166,066
Prior | 538,121 | 321,455
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,307,254 | 1,965,140
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 359,324 | 568,200
Fiscal year before current fiscal year | 538,921 | 417,334
Two years before current fiscal year | 341,037 | 299,973
Three years before current fiscal year | 287,273 | 174,448
Four years before current fiscal year | 223,273 | 150,811
Prior | 513,758 | 304,585
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 2,263,586 | 1,915,351
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Special Mention |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 2,061 | 3,185
Fiscal year before current fiscal year | 1,457 | 1,206
Two years before current fiscal year | 1,153 | 1,836
Three years before current fiscal year | 1,799 | 1,295
Four years before current fiscal year | 993 | 10,609
Prior | 15,212 | 8,632
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 22,675 | 26,763
Real Estate Loan | Commercial And Multifamily Portfolio Segment | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 3,865 | 2,007
Fiscal year before current fiscal year | 490 | 714
Two years before current fiscal year | 829 | 6,242
Three years before current fiscal year | 1,003 | 1,179
Four years before current fiscal year | 5,655 | 4,646
Prior | 9,151 | 8,238
Revolving Loans | 0 | 0
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 20,993 | 23,026
1-4 Family | Real Estate Loan |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 45,589 | 79,478
Fiscal year before current fiscal year | 93,666 | 94,900
Two years before current fiscal year | 85,860 | 39,022
Three years before current fiscal year | 30,486 | 46,049
Four years before current fiscal year | 37,098 | 36,794
Prior | 84,004 | 60,577
Revolving Loans | 47,527 | 43,493
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 424,230 | 400,313
1-4 Family | Real Estate Loan | Pass |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 45,334 | 78,889
Fiscal year before current fiscal year | 93,175 | 94,404
Two years before current fiscal year | 85,280 | 35,554
Three years before current fiscal year | 30,080 | 44,248
Four years before current fiscal year | 33,992 | 30,735
Prior | 74,577 | 52,131
Revolving Loans | 47,094 | 42,800
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 409,532 | 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 | 151 | 0
Two years before current fiscal year | 139 | 1,934
Three years before current fiscal year | 40 | 499
Four years before current fiscal year | 182 | 2,601
Prior | 1,149 | 1,196
Revolving Loans | 129 | 41
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | 1,790 | 6,505
1-4 Family | Real Estate Loan | Substandard |  |
Credit Quality Information [Abstract] |  |
Current fiscal year | 255 | 355
Fiscal year before current fiscal year | 340 | 496
Two years before current fiscal year | 441 | 1,534
Three years before current fiscal year | 366 | 1,302
Four years before current fiscal year | 2,924 | 3,458
Prior | 8,278 | 7,250
Revolving Loans | 304 | 652
Loans Receivable Aging Analysis [Abstract] |  |
Total Loans Receivable | $ 12,908 | $ 15,047

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