LOANS AND ALLOWANCE FOR CREDIT LOSSES - Summary of Loans by Risk Category and Past Due Status (Details) $ in Thousands	Jun. 30, 2021 USD ($)
2021 YTD	$ 343,904
2020	695,957
2019	789,444
2018	764,205
2017	512,825
Prior	978,883
Revolving Loans	207,315
Total	4,292,533
Satisfactory
2021 YTD	343,904
2020	695,941
2019	787,903
2018	761,474
2017	501,025
Prior	943,909
Revolving Loans	206,200
Total	4,240,356
Watch
2021 YTD	0
2020	0
2019	1,363
2018	2,710
2017	11,561
Prior	27,705
Revolving Loans	105
Total	43,444
Special Mention
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	0
Classified
2021 YTD	0
2020	16
2019	178
2018	21
2017	239
Prior	7,269
Revolving Loans	1,010
Total	8,733
Commercial Real Estate
2021 YTD	32,360
2020	131,690
2019	244,807
2018	236,814
2017	253,252
Prior	650,330
Revolving Loans	29,979
Total	1,579,232
Commercial Real Estate \| Satisfactory
2021 YTD	32,360
2020	131,690
2019	244,807
2018	236,814
2017	241,697
Prior	623,701
Revolving Loans	29,979
Total	1,541,048
Commercial Real Estate \| Watch
2021 YTD	0
2020	0
2019	0
2018	0
2017	11,555
Prior	21,319
Revolving Loans	0
Total	32,874
Commercial Real Estate \| Special Mention
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	0
Commercial Real Estate \| Classified
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	5,310
Revolving Loans	0
Total	5,310
Consumer Loan
2021 YTD	11,989
2020	15,637
2019	10,793
2018	14,171
2017	6,891
Prior	33,434
Revolving Loans	124,560
Total	217,475
Consumer Loan \| Satisfactory
2021 YTD	11,989
2020	15,621
2019	10,753
2018	14,127
2017	6,844
Prior	33,042
Revolving Loans	124,129
Total	216,505
Consumer Loan \| Watch
2021 YTD	0
2020	0
2019	0
2018	23
2017	6
Prior	42
Revolving Loans	30
Total	101
Consumer Loan \| Special Mention
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	0
Consumer Loan \| Classified
2021 YTD	0
2020	16
2019	40
2018	21
2017	41
Prior	350
Revolving Loans	401
Total	869
Construction and land development
2021 YTD	2,002
2020	23,261
2019	10,848
2018	5,044
2017	3,643
Prior	6,201
Revolving Loans	1,912
Total	52,911
Construction and land development \| Satisfactory
2021 YTD	2,002
2020	23,261
2019	10,848
2018	5,044
2017	3,643
Prior	6,201
Revolving Loans	1,444
Total	52,443
Construction and land development \| Watch
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	0
Construction and land development \| Special Mention
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	0
Construction and land development \| Classified
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	468
Total	468
Commercial business
2021 YTD	71,817
2020	26,803
2019	25,128
2018	18,846
2017	24,258
Prior	60,140
Revolving Loans	46,060
Total	273,052
Commercial business \| Satisfactory
2021 YTD	71,817
2020	26,803
2019	25,128
2018	16,292
2017	24,258
Prior	57,442
Revolving Loans	46,021
Total	267,761
Commercial business \| Watch
2021 YTD	0
2020	0
2019	0
2018	2,554
2017	0
Prior	2,638
Revolving Loans	0
Total	5,192
Commercial business \| Special Mention
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	0
Commercial business \| Classified
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	60
Revolving Loans	39
Total	99
One- to four-family residential
2021 YTD	143,129
2020	196,803
2019	112,214
2018	73,174
2017	16,476
Prior	137,540
Revolving Loans	1,677
Total	681,013
One- to four-family residential \| Satisfactory
2021 YTD	143,129
2020	196,803
2019	112,076
2018	73,041
2017	16,278
Prior	135,781
Revolving Loans	1,500
Total	678,608
One- to four-family residential \| Watch
2021 YTD	0
2020	0
2019	0
2018	133
2017	0
Prior	227
Revolving Loans	75
Total	435
One- to four-family residential \| Special Mention
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	0
One- to four-family residential \| Classified
2021 YTD	0
2020	0
2019	138
2018	0
2017	198
Prior	1,532
Revolving Loans	102
Total	1,970
One- to four-family residential construction
2021 YTD	8,535
2020	12,159
2019	2,056
2018	0
2017	0
Prior	6
Revolving Loans	0
Total	22,756
One- to four-family residential construction \| Satisfactory
2021 YTD	8,535
2020	12,159
2019	693
2018	0
2017	0
Prior	6
Revolving Loans	0
Total	21,393
One- to four-family residential construction \| Watch
2021 YTD	0
2020	0
2019	1,363
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	1,363
One- to four-family residential construction \| Special Mention
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	0
One- to four-family residential construction \| Classified
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	0
Subdivision construction
2021 YTD	973
2020	1,014
2019	326
2018	270
2017	840
Prior	1,074
Revolving Loans	0
Total	4,497
Subdivision construction \| Satisfactory
2021 YTD	973
2020	1,014
2019	326
2018	270
2017	840
Prior	1,057
Revolving Loans	0
Total	4,480
Subdivision construction \| Watch
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	0
Subdivision construction \| Special Mention
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	0
Subdivision construction \| Classified
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	17
Revolving Loans	0
Total	17
Other Construction
2021 YTD	44,958
2020	198,667
2019	142,842
2018	55,563
2017	334
Prior	0
Revolving Loans	0
Total	442,364
Other Construction \| Satisfactory
2021 YTD	44,958
2020	198,667
2019	142,842
2018	55,563
2017	334
Prior	0
Revolving Loans	0
Total	442,364
Other Construction \| Watch
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	0
Other Construction \| Special Mention
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	0
Other Construction \| Classified
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	0
Other residential
2021 YTD	28,141
2020	89,923
2019	240,430
2018	360,323
2017	207,131
Prior	90,158
Revolving Loans	3,127
Total	1,019,233
Other residential \| Satisfactory
2021 YTD	28,141
2020	89,923
2019	240,430
2018	360,323
2017	207,131
Prior	86,679
Revolving Loans	3,127
Total	1,015,754
Other residential \| Watch
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	3,479
Revolving Loans	0
Total	3,479
Other residential \| Special Mention
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	0
Other residential \| Classified
2021 YTD	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Revolving Loans	0
Total	$ 0

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