LOANS AND ALLOWANCE FOR CREDIT LOSSES - Summary of Credit Exposure in Company Loan Portfolio (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($)
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	$ 628,756
Credit Exposure 2019	286,256
Credit Exposure 2018	212,899
Credit Exposure 2017	163,831
Credit Exposure 2016	174,558
Credit Exposure Prior	274,903
Revolving Loans Amortized Cost	125,616
Total	1,866,819
Credit Exposure 2020.Charge - offs	(243)
Credit Exposure 2019.Charge - offs	(63)
Credit Exposure 2018.Charge - offs	(92)
Credit Exposure 2017.Charge - offs	(43)
Credit Exposure 2016.Charge - offs	(12)
Credit Exposure Prior. Charge - offs	(65)
Credit Exposure Revolving Loans Amortized Cost. Charge - offs	(25)
Total	(543)
Credit Exposure 2020, Recoveries	49
Credit Exposure 2019, Recoveries	2
Credit Exposure 2018, Recoveries	55
Credit Exposure 2017, Recoveries	8
Credit Exposure 2016, Recoveries	24
Credit Exposure Prior, Recoveries	30
Credit Exposure Revolving Loans Amortized Cost, Recoveries	44
Total	212
Credit Exposure 2020,Current period net	(194)
Credit Exposure 2019,Current period net	(61)
Credit Exposure 2018,Current period net	(37)
Credit Exposure 2017,Current period net	(35)
Credit Exposure 2016,Current period net	12
Credit Exposure Prior,Current period net	(35)
Credit Exposure Revolving Loans Amortized Cost,Current period net	19
Total	(331)
Pass
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	628,236
Credit Exposure 2019	281,239
Credit Exposure 2018	205,907
Credit Exposure 2017	148,724
Credit Exposure 2016	157,326
Credit Exposure Prior	264,245
Revolving Loans Amortized Cost	125,616
Total	1,811,293
Special Mention
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	496
Credit Exposure 2019	2,918
Credit Exposure 2018	3,773
Credit Exposure 2017	5,922
Credit Exposure 2016	7,048
Credit Exposure Prior	652
Total	20,809
Substandard
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2019	923
Credit Exposure 2018	2,565
Credit Exposure 2017	4,963
Credit Exposure 2016	5,192
Credit Exposure Prior	8,369
Total	22,012
Nonaccrual
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	24
Credit Exposure 2019	1,176
Credit Exposure 2018	654
Credit Exposure 2017	4,222
Credit Exposure 2016	4,992
Credit Exposure Prior	1,637
Total	12,705
Commercial and industrial
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	278,811
Credit Exposure 2019	30,989
Credit Exposure 2018	13,635
Credit Exposure 2017	8,456
Credit Exposure 2016	7,512
Credit Exposure Prior	16,294
Revolving Loans Amortized Cost	90,074
Total	445,771
Credit Exposure 2018.Charge - offs	(43)
Credit Exposure Revolving Loans Amortized Cost. Charge - offs	(25)
Total	(68)
Credit Exposure 2018, Recoveries	43
Credit Exposure Prior, Recoveries	14
Credit Exposure Revolving Loans Amortized Cost, Recoveries	44
Total	101
Credit Exposure Prior,Current period net	14
Credit Exposure Revolving Loans Amortized Cost,Current period net	19
Total	33
Commercial and industrial | Pass
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	278,687
Credit Exposure 2019	30,563
Credit Exposure 2018	12,860
Credit Exposure 2017	4,366
Credit Exposure 2016	6,131
Credit Exposure Prior	16,294
Revolving Loans Amortized Cost	90,074
Total	438,975
Commercial and industrial | Special Mention
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	124
Credit Exposure 2019	119
Credit Exposure 2018	222
Credit Exposure 2017	4,040
Credit Exposure 2016	1,324
Total	5,829
Commercial and industrial | Substandard
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2019	307
Credit Exposure 2018	540
Credit Exposure 2017	50
Credit Exposure 2016	43
Total	940
Commercial and industrial | Nonaccrual
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2018	13
Credit Exposure 2016	14
Total	27
Construction and development
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	118,946
Credit Exposure 2019	77,535
Credit Exposure 2018	26,217
Credit Exposure 2017	25,514
Credit Exposure 2016	8,422
Credit Exposure Prior	10,507
Revolving Loans Amortized Cost	3,266
Total	270,407
Construction and development | Pass
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	118,590
Credit Exposure 2019	76,926
Credit Exposure 2018	26,212
Credit Exposure 2017	24,524
Credit Exposure 2016	7,742
Credit Exposure Prior	10,507
Revolving Loans Amortized Cost	3,266
Total	267,767
Construction and development | Special Mention
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	356
Credit Exposure 2017	990
Total	1,346
Construction and development | Substandard
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2019	609
Credit Exposure 2018	5
Credit Exposure 2016	680
Total	1,294
Commercial real estate
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	91,819
Credit Exposure 2019	84,609
Credit Exposure 2018	95,245
Credit Exposure 2017	82,231
Credit Exposure 2016	101,884
Credit Exposure Prior	132,538
Revolving Loans Amortized Cost	5,890
Total	594,216
Credit Exposure Prior, Recoveries	1
Total	1
Credit Exposure Prior,Current period net	1
Total	1
Commercial real estate | Pass
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	91,819
Credit Exposure 2019	80,753
Credit Exposure 2018	89,542
Credit Exposure 2017	72,311
Credit Exposure 2016	86,946
Credit Exposure Prior	123,463
Revolving Loans Amortized Cost	5,890
Total	550,724
Commercial real estate | Special Mention
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2019	2,716
Credit Exposure 2018	3,542
Credit Exposure 2017	849
Credit Exposure 2016	5,724
Credit Exposure Prior	449
Total	13,280
Commercial real estate | Substandard
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2018	2,010
Credit Exposure 2017	4,913
Credit Exposure 2016	4,445
Credit Exposure Prior	8,240
Total	19,608
Commercial real estate | Nonaccrual
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2019	1,140
Credit Exposure 2018	151
Credit Exposure 2017	4,158
Credit Exposure 2016	4,769
Credit Exposure Prior	386
Total	10,604
Farmland
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	17,444
Credit Exposure 2019	12,668
Credit Exposure 2018	10,327
Credit Exposure 2017	6,620
Credit Exposure 2016	9,904
Credit Exposure Prior	15,681
Revolving Loans Amortized Cost	5,864
Total	78,508
Farmland | Pass
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	17,444
Credit Exposure 2019	12,668
Credit Exposure 2018	10,327
Credit Exposure 2017	6,620
Credit Exposure 2016	9,904
Credit Exposure Prior	15,402
Revolving Loans Amortized Cost	5,864
Total	78,229
Farmland | Special Mention
Financing Receivable Recorded Investment [Line Items]
Credit Exposure Prior	35
Total	35
Farmland | Substandard
Financing Receivable Recorded Investment [Line Items]
Credit Exposure Prior	129
Total	129
Farmland | Nonaccrual
Financing Receivable Recorded Investment [Line Items]
Credit Exposure Prior	115
Total	115
1-4 family residential
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	87,578
Credit Exposure 2019	62,937
Credit Exposure 2018	52,413
Credit Exposure 2017	37,268
Credit Exposure 2016	44,021
Credit Exposure Prior	94,788
Revolving Loans Amortized Cost	10,091
Total	389,096
Credit Exposure 2016.Charge - offs	(9)
Credit Exposure Prior. Charge - offs	(59)
Total	(68)
Credit Exposure Prior, Recoveries	2
Total	2
Credit Exposure 2016,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 2020	87,578
Credit Exposure 2019	62,937
Credit Exposure 2018	52,087
Credit Exposure 2017	37,224
Credit Exposure 2016	43,858
Credit Exposure Prior	93,486
Revolving Loans Amortized Cost	10,091
Total	387,261
1-4 family residential | Special Mention
Financing Receivable Recorded Investment [Line Items]
Credit Exposure Prior	168
Total	168
1-4 family residential | Nonaccrual
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2018	326
Credit Exposure 2017	44
Credit Exposure 2016	163
Credit Exposure Prior	1,134
Total	1,667
Multi-family residential
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	5,889
Credit Exposure 2019	4,498
Credit Exposure 2018	3,617
Credit Exposure 2017	1,371
Credit Exposure 2016	1,737
Credit Exposure Prior	4,391
Revolving Loans Amortized Cost	198
Total	21,701
Multi-family residential | Pass
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	5,889
Credit Exposure 2019	4,498
Credit Exposure 2018	3,617
Credit Exposure 2017	1,371
Credit Exposure 2016	1,737
Credit Exposure Prior	4,391
Revolving Loans Amortized Cost	198
Total	21,701
Consumer and Overdrafts
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	24,780
Credit Exposure 2019	11,295
Credit Exposure 2018	9,509
Credit Exposure 2017	1,728
Credit Exposure 2016	736
Credit Exposure Prior	513
Revolving Loans Amortized Cost	2,825
Total	51,386
Credit Exposure 2020.Charge - offs	(243)
Credit Exposure 2019.Charge - offs	(63)
Credit Exposure 2018.Charge - offs	(31)
Credit Exposure 2017.Charge - offs	(43)
Credit Exposure 2016.Charge - offs	(3)
Credit Exposure Prior. Charge - offs	(6)
Total	(389)
Credit Exposure 2020, Recoveries	49
Credit Exposure 2019, Recoveries	2
Credit Exposure 2018, Recoveries	12
Credit Exposure 2017, Recoveries	8
Credit Exposure 2016, Recoveries	4
Credit Exposure Prior, Recoveries	13
Total	88
Credit Exposure 2020,Current period net	(194)
Credit Exposure 2019,Current period net	(61)
Credit Exposure 2018,Current period net	(19)
Credit Exposure 2017,Current period net	(35)
Credit Exposure 2016,Current period net	1
Credit Exposure Prior,Current period net	7
Total	(301)
Consumer and Overdrafts | Pass
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	24,740
Credit Exposure 2019	11,176
Credit Exposure 2018	9,369
Credit Exposure 2017	1,701
Credit Exposure 2016	735
Credit Exposure Prior	513
Revolving Loans Amortized Cost	2,825
Total	51,059
Consumer and Overdrafts | Special Mention
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	16
Credit Exposure 2019	83
Credit Exposure 2018	9
Credit Exposure 2017	7
Total	115
Consumer and Overdrafts | Nonaccrual
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	24
Credit Exposure 2019	36
Credit Exposure 2018	131
Credit Exposure 2017	20
Credit Exposure 2016	1
Total	212
Agricultural
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	3,489
Credit Exposure 2019	1,725
Credit Exposure 2018	1,936
Credit Exposure 2017	643
Credit Exposure 2016	342
Credit Exposure Prior	191
Revolving Loans Amortized Cost	7,408
Total	15,734
Credit Exposure 2018.Charge - offs	(18)
Total	(18)
Credit Exposure 2016, Recoveries	20
Total	20
Credit Exposure 2018,Current period net	(18)
Credit Exposure 2016,Current period net	20
Total	2
Agricultural | Pass
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2020	3,489
Credit Exposure 2019	1,718
Credit Exposure 2018	1,893
Credit Exposure 2017	607
Credit Exposure 2016	273
Credit Exposure Prior	189
Revolving Loans Amortized Cost	7,408
Total	15,577
Agricultural | Special Mention
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2017	36
Total	36
Agricultural | Substandard
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2019	7
Credit Exposure 2018	10
Credit Exposure 2016	24
Total	41
Agricultural | Nonaccrual
Financing Receivable Recorded Investment [Line Items]
Credit Exposure 2018	33
Credit Exposure 2016	45
Credit Exposure Prior	2
Total	$ 80