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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Summary of Credit Exposure in Company Loan Portfolio (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | $ 318,569 | $ 628,756
Credit Exposure 2020 | 456,548 | 286,256
Credit Exposure 2019 | 248,182 | 212,899
Credit Exposure 2018 | 200,374 | 163,831
Credit Exposure 2017 | 146,192 | 174,558
Credit Exposure Prior | 419,167 | 274,903
Revolving Loans Amortized Cost | 123,335 | 125,616
Total | 1,912,367 | 1,866,819
Credit Exposure 2021.Charge - offs | 49 | 243
Credit Exposure 2020.Charge - offs | (6) | (63)
Credit Exposure 2019.Charge - offs | (55) | (92)
Credit Exposure 2018.Charge - offs | (16) |
Credit Exposure 2017.Charge - offs | (471) | (12)
Credit Exposure Prior.Charge - offs | (271) | (65)
Credit Exposure Revolving Loans Amortized Cost.Charge - offs | (7) | (25)
Total | (875) | (543)
Credit Exposure 2021, Recoveries | 14 | 49
Credit Exposure 2020, Recoveries |  | 2
Credit Exposure 2019, Recoveries |  | 55
Credit Exposure 2018, Recoveries |  | 8
Credit Exposure 2017, Recoveries | 1 | 24
Credit Exposure Prior, Recoveries | 5 | 30
Credit Exposure Revolving Loans Amortized Cost, Recoveries | 6 | 44
Total | 26 | 212
Credit Exposure 2021,Current period net | (35) | (194)
Credit Exposure 2020,Current period net | (6) | (61)
Credit Exposure 2019,Current period net | (55) | (37)
Credit Exposure 2018,Current period net | (16) | (35)
Credit Exposure 2017,Current period net | (470) | 12
Credit Exposure Prior,Current period net | (266) | (35)
Credit Exposure Revolving Loans Amortized Cost,Current period net | (1) | 19
Total | (849) | (331)
Credit Exposure 2020.Charge - offs | (49) | (243)
Pass |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 318,154 | 628,236
Credit Exposure 2020 | 448,412 | 281,239
Credit Exposure 2019 | 238,230 | 205,907
Credit Exposure 2018 | 184,135 | 148,724
Credit Exposure 2017 | 129,905 | 157,326
Credit Exposure Prior | 396,745 | 264,245
Revolving Loans Amortized Cost | 123,335 | 125,616
Total | 1,838,916 | 1,811,293
Special Mention |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 415 | 496
Credit Exposure 2020 | 730 | 2,918
Credit Exposure 2019 | 1,791 | 3,773
Credit Exposure 2018 | 4,120 | 5,922
Credit Exposure 2017 | 2,024 | 7,048
Credit Exposure Prior | 2,190 | 652
Total | 11,270 | 20,809
Substandard |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2020 | 7,362 | 923
Credit Exposure 2019 | 7,568 | 2,565
Credit Exposure 2018 | 11,398 | 4,963
Credit Exposure 2017 | 13,991 | 5,192
Credit Exposure Prior | 18,479 | 8,369
Total | 58,798 | 22,012
Nonaccrual |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 |  | 24
Credit Exposure 2020 | 44 | 1,176
Credit Exposure 2019 | 593 | 654
Credit Exposure 2018 | 721 | 4,222
Credit Exposure 2017 | 272 | 4,992
Credit Exposure Prior | 1,753 | 1,637
Total | 3,383 | 12,705
Commercial and industrial |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 190,664 | 278,811
Credit Exposure 2020 | 117,882 | 30,989
Credit Exposure 2019 | 26,522 | 13,635
Credit Exposure 2018 | 12,471 | 8,456
Credit Exposure 2017 | 7,091 | 7,512
Credit Exposure Prior | 21,918 | 16,294
Revolving Loans Amortized Cost | 83,943 | 90,074
Total | 460,491 | 445,771
Credit Exposure 2019.Charge - offs |  | (43)
Credit Exposure Revolving Loans Amortized Cost.Charge - offs | (7) | (25)
Total | (7) | (68)
Credit Exposure 2019, Recoveries |  | 43
Credit Exposure Prior, Recoveries | 1 | 14
Credit Exposure Revolving Loans Amortized Cost, Recoveries | 6 | 44
Total | 7 | 101
Credit Exposure Prior,Current period net | 1 | 14
Credit Exposure Revolving Loans Amortized Cost,Current period net | (1) | 19
Total |  | 33
Commercial and industrial | Pass |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 190,664 | 278,687
Credit Exposure 2020 | 117,479 | 30,563
Credit Exposure 2019 | 26,166 | 12,860
Credit Exposure 2018 | 12,168 | 4,366
Credit Exposure 2017 | 6,998 | 6,131
Credit Exposure Prior | 21,873 | 16,294
Revolving Loans Amortized Cost | 83,943 | 90,074
Total | 459,291 | 438,975
Commercial and industrial | Special Mention |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 |  | 124
Credit Exposure 2020 | 113 | 119
Credit Exposure 2019 |  | 222
Credit Exposure 2018 |  | 4,040
Credit Exposure 2017 | 34 | 1,324
Total | 147 | 5,829
Commercial and industrial | Substandard |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2020 | 290 | 307
Credit Exposure 2019 | 65 | 540
Credit Exposure 2018 | 230 | 50
Credit Exposure 2017 | 49 | 43
Credit Exposure Prior | 31 |
Total | 665 | 940
Commercial and industrial | Nonaccrual |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2019 | 291 | 13
Credit Exposure 2018 | 73 |
Credit Exposure 2017 | 10 | 14
Credit Exposure Prior | 14 |
Total | 388 | 27
Construction and development |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 30,281 | 118,946
Credit Exposure 2020 | 105,473 | 77,535
Credit Exposure 2019 | 55,915 | 26,217
Credit Exposure 2018 | 25,055 | 25,514
Credit Exposure 2017 | 20,412 | 8,422
Credit Exposure Prior | 17,829 | 10,507
Revolving Loans Amortized Cost | 2,921 | 3,266
Total | 257,886 | 270,407
Credit Exposure Prior, Recoveries | 1 |
Total | 1 |
Credit Exposure Prior,Current period net | 1 |
Total | 1 |
Construction and development | Pass |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 30,281 | 118,590
Credit Exposure 2020 | 105,473 | 76,926
Credit Exposure 2019 | 50,592 | 26,212
Credit Exposure 2018 | 25,051 | 24,524
Credit Exposure 2017 | 19,434 | 7,742
Credit Exposure Prior | 17,829 | 10,507
Revolving Loans Amortized Cost | 2,921 | 3,266
Total | 251,581 | 267,767
Construction and development | Special Mention |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 |  | 356
Credit Exposure 2018 |  | 990
Credit Exposure 2017 | 978 |
Total | 978 | 1,346
Construction and development | Substandard |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2020 |  | 609
Credit Exposure 2019 | 5,093 | 5
Credit Exposure 2018 | 4 |
Credit Exposure 2017 |  | 680
Total | 5,097 | 1,294
Construction and development | Nonaccrual |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2019 | 230 |
Total | 230 |
Commercial real estate |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 50,856 | 91,819
Credit Exposure 2020 | 104,445 | 84,609
Credit Exposure 2019 | 78,474 | 95,245
Credit Exposure 2018 | 93,517 | 82,231
Credit Exposure 2017 | 75,949 | 101,884
Credit Exposure Prior | 220,074 | 132,538
Revolving Loans Amortized Cost | 7,164 | 5,890
Total | 630,479 | 594,216
Credit Exposure 2019.Charge - offs | (17) |
Credit Exposure 2017.Charge - offs | (470) |
Credit Exposure Prior.Charge - offs | (271) |
Total | (758) |
Credit Exposure Prior, Recoveries |  | 1
Total |  | 1
Credit Exposure 2019,Current period net | (17) |
Credit Exposure 2017,Current period net | (470) |
Credit Exposure Prior,Current period net | (271) | 1
Total | (758) | 1
Commercial real estate | Pass |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 50,441 | 91,819
Credit Exposure 2020 | 96,823 | 80,753
Credit Exposure 2019 | 74,450 | 89,542
Credit Exposure 2018 | 78,078 | 72,311
Credit Exposure 2017 | 61,686 | 86,946
Credit Exposure Prior | 199,507 | 123,463
Revolving Loans Amortized Cost | 7,164 | 5,890
Total | 568,149 | 550,724
Commercial real estate | Special Mention |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 415 |
Credit Exposure 2020 | 550 | 2,716
Credit Exposure 2019 | 1,621 | 3,542
Credit Exposure 2018 | 4,112 | 849
Credit Exposure 2017 | 841 | 5,724
Credit Exposure Prior | 1,880 | 449
Total | 9,419 | 13,280
Commercial real estate | Substandard |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2020 | 7,072 |
Credit Exposure 2019 | 2,403 | 2,010
Credit Exposure 2018 | 11,155 | 4,913
Credit Exposure 2017 | 13,216 | 4,445
Credit Exposure Prior | 18,301 | 8,240
Total | 52,147 | 19,608
Commercial real estate | Nonaccrual |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2020 |  | 1,140
Credit Exposure 2019 |  | 151
Credit Exposure 2018 | 172 | 4,158
Credit Exposure 2017 | 206 | 4,769
Credit Exposure Prior | 386 | 386
Total | 764 | 10,604
Farmland |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 6,131 | 17,444
Credit Exposure 2020 | 14,242 | 12,668
Credit Exposure 2019 | 11,905 | 10,327
Credit Exposure 2018 | 9,365 | 6,620
Credit Exposure 2017 | 5,939 | 9,904
Credit Exposure Prior | 23,975 | 15,681
Revolving Loans Amortized Cost | 5,310 | 5,864
Total | 76,867 | 78,508
Farmland | Pass |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 6,131 | 17,444
Credit Exposure 2020 | 14,242 | 12,668
Credit Exposure 2019 | 11,905 | 10,327
Credit Exposure 2018 | 9,365 | 6,620
Credit Exposure 2017 | 5,939 | 9,904
Credit Exposure Prior | 23,702 | 15,402
Revolving Loans Amortized Cost | 5,310 | 5,864
Total | 76,594 | 78,229
Farmland | Special Mention |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure Prior | 33 | 35
Total | 33 | 35
Farmland | Substandard |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure Prior | 125 | 129
Total | 125 | 129
Farmland | Nonaccrual |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure Prior | 115 | 115
Total | 115 | 115
1-4 family residential |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 20,613 | 87,578
Credit Exposure 2020 | 85,266 | 62,937
Credit Exposure 2019 | 60,209 | 52,413
Credit Exposure 2018 | 47,091 | 37,268
Credit Exposure 2017 | 33,660 | 44,021
Credit Exposure Prior | 129,717 | 94,788
Revolving Loans Amortized Cost | 12,986 | 10,091
Total | 389,542 | 389,096
Credit Exposure 2017.Charge - offs |  | (9)
Credit Exposure Prior.Charge - offs |  | (59)
Total |  | (68)
Credit Exposure Prior, Recoveries |  | 2
Total |  | 2
Credit Exposure 2017,Current period net |  | (9)
Credit Exposure Prior,Current period net |  | (57)
Total |  | (66)
1-4 family residential | Pass |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 20,613 | 87,578
Credit Exposure 2020 | 85,266 | 62,937
Credit Exposure 2019 | 60,095 | 52,087
Credit Exposure 2018 | 46,771 | 37,224
Credit Exposure 2017 | 33,492 | 43,858
Credit Exposure Prior | 128,204 | 93,486
Revolving Loans Amortized Cost | 12,986 | 10,091
Total | 387,427 | 387,261
1-4 family residential | Special Mention |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2019 | 114 |
Credit Exposure 2017 | 132 |
Credit Exposure Prior | 277 | 168
Total | 523 | 168
1-4 family residential | Nonaccrual |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2019 |  | 326
Credit Exposure 2018 | 320 | 44
Credit Exposure 2017 | 36 | 163
Credit Exposure Prior | 1,236 | 1,134
Total | 1,592 | 1,667
Multi-family residential |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 11,979 | 5,889
Credit Exposure 2020 | 6,133 | 4,498
Credit Exposure 2019 | 4,463 | 3,617
Credit Exposure 2018 | 3,575 | 1,371
Credit Exposure 2017 | 1,328 | 1,737
Credit Exposure Prior | 4,376 | 4,391
Revolving Loans Amortized Cost | 236 | 198
Total | 32,090 | 21,701
Multi-family residential | Pass |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 11,979 | 5,889
Credit Exposure 2020 | 6,133 | 4,498
Credit Exposure 2019 | 4,463 | 3,617
Credit Exposure 2018 | 3,575 | 1,371
Credit Exposure 2017 | 641 | 1,737
Credit Exposure Prior | 4,376 | 4,391
Revolving Loans Amortized Cost | 236 | 198
Total | 31,403 | 21,701
Multi-family residential | Substandard |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2017 | 687 |
Total | 687 |
Consumer and Overdrafts |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 7,655 | 24,780
Credit Exposure 2020 | 20,502 | 11,295
Credit Exposure 2019 | 9,106 | 9,509
Credit Exposure 2018 | 7,703 | 1,728
Credit Exposure 2017 | 1,316 | 736
Credit Exposure Prior | 921 | 513
Revolving Loans Amortized Cost | 2,904 | 2,825
Total | 50,107 | 51,386
Credit Exposure 2021.Charge - offs | 49 | 243
Credit Exposure 2020.Charge - offs | (6) | (63)
Credit Exposure 2019.Charge - offs | (38) | (31)
Credit Exposure 2018.Charge - offs | (16) | (43)
Credit Exposure 2017.Charge - offs | (1) | (3)
Credit Exposure Prior.Charge - offs |  | (6)
Total | (110) | (389)
Credit Exposure 2021, Recoveries | 14 | 49
Credit Exposure 2020, Recoveries |  | 2
Credit Exposure 2019, Recoveries |  | 12
Credit Exposure 2018, Recoveries |  | 8
Credit Exposure 2017, Recoveries | 1 | 4
Credit Exposure Prior, Recoveries | 3 | 13
Total | 18 | 88
Credit Exposure 2021,Current period net | (35) | (194)
Credit Exposure 2020,Current period net | (6) | (61)
Credit Exposure 2019,Current period net | (38) | (19)
Credit Exposure 2018,Current period net | (16) | (35)
Credit Exposure 2017,Current period net |  | 1
Credit Exposure Prior,Current period net | 3 | 7
Total | (92) | (301)
Credit Exposure 2020.Charge - offs | (49) | (243)
Consumer and Overdrafts | Pass |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 7,655 | 24,740
Credit Exposure 2020 | 20,391 | 11,176
Credit Exposure 2019 | 8,978 | 9,369
Credit Exposure 2018 | 7,586 | 1,701
Credit Exposure 2017 | 1,297 | 735
Credit Exposure Prior | 921 | 513
Revolving Loans Amortized Cost | 2,904 | 2,825
Total | 49,732 | 51,059
Consumer and Overdrafts | Special Mention |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 |  | 16
Credit Exposure 2020 | 67 | 83
Credit Exposure 2019 | 56 | 9
Credit Exposure 2018 | 8 | 7
Credit Exposure 2017 | 5 |
Total | 136 | 115
Consumer and Overdrafts | Nonaccrual |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 |  | 24
Credit Exposure 2020 | 44 | 36
Credit Exposure 2019 | 72 | 131
Credit Exposure 2018 | 109 | 20
Credit Exposure 2017 | 14 | 1
Total | 239 | 212
Agricultural |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 390 | 3,489
Credit Exposure 2020 | 2,605 | 1,725
Credit Exposure 2019 | 1,588 | 1,936
Credit Exposure 2018 | 1,597 | 643
Credit Exposure 2017 | 497 | 342
Credit Exposure Prior | 357 | 191
Revolving Loans Amortized Cost | 7,871 | 7,408
Total | 14,905 | 15,734
Credit Exposure 2019.Charge - offs |  | (18)
Total |  | (18)
Credit Exposure 2017, Recoveries |  | 20
Total |  | 20
Credit Exposure 2019,Current period net |  | (18)
Credit Exposure 2017,Current period net |  | 20
Total |  | 2
Agricultural | Pass |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2021 | 390 | 3,489
Credit Exposure 2020 | 2,605 | 1,718
Credit Exposure 2019 | 1,581 | 1,893
Credit Exposure 2018 | 1,541 | 607
Credit Exposure 2017 | 418 | 273
Credit Exposure Prior | 333 | 189
Revolving Loans Amortized Cost | 7,871 | 7,408
Total | 14,739 | 15,577
Agricultural | Special Mention |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2018 |  | 36
Credit Exposure 2017 | 34 |
Total | 34 | 36
Agricultural | Substandard |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2020 |  | 7
Credit Exposure 2019 | 7 | 10
Credit Exposure 2018 | 9 |
Credit Exposure 2017 | 39 | 24
Credit Exposure Prior | 22 |
Total | 77 | 41
Agricultural | Nonaccrual |  |
Financing Receivable Recorded Investment [Line Items] |  |
Credit Exposure 2019 |  | 33
Credit Exposure 2018 | 47 |
Credit Exposure 2017 | 6 | 45
Credit Exposure Prior | 2 | 2
Total | $ 55 | $ 80

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