ALLOWANCE FOR CREDIT LOSSES AND CREDIT QUALITY - Risk category of loans by loan segment and origination (Details) $ in Thousands	Jun. 30, 2021 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
2021	$ 524,963
2020	919,102
2019	489,964
2018	370,137
2017	275,901
Prior	363,187
Term Total	2,943,254
Revolving	1,410,455
Total	4,353,709
Other consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021	14,530
2020	25,253
2019	11,884
2018	8,388
2017	4,452
Prior	1,729
Term Total	66,236
Revolving	34,313
Total	100,549
Other consumer loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	1,802
2020	6,029
2019	1,633
2018	0
2017	1,327
Prior	0
Term Total	10,791
Revolving	24,443
Total	35,234
Other consumer loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0
2020	0
2019	253
2018	0
2017	0
Prior	0
Term Total	253
Revolving	0
Total	253
Other consumer loans | Not Rated
Financing Receivable, Credit Quality Indicator [Line Items]
2021	12,728
2020	19,224
2019	9,998
2018	8,388
2017	3,125
Prior	1,729
Term Total	55,192
Revolving	9,870
Total	65,062
Commercial and industrial loans | Working capital lines of credit loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021	4,222
2020	7,057
2019	13,170
2018	2,002
2017	1,171
Prior	505
Term Total	28,127
Revolving	588,372
Total	616,499
Commercial and industrial loans | Working capital lines of credit loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	4,222
2020	7,057
2019	13,084
2018	2,002
2017	998
Prior	505
Term Total	27,868
Revolving	494,580
Total	522,448
Commercial and industrial loans | Working capital lines of credit loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Term Total	0
Revolving	72,310
Total	72,310
Commercial and industrial loans | Working capital lines of credit loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0
2020	0
2019	86
2018	0
2017	173
Prior	0
Term Total	259
Revolving	21,482
Total	21,741
Commercial and industrial loans | Non-working capital loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021	240,480
2020	225,509
2019	98,197
2018	82,428
2017	37,724
Prior	25,822
Term Total	710,160
Revolving	169,595
Total	879,755
Commercial and industrial loans | Non-working capital loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	231,811
2020	212,502
2019	95,064
2018	75,452
2017	28,365
Prior	23,923
Term Total	667,117
Revolving	163,284
Total	830,401
Commercial and industrial loans | Non-working capital loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2021	3,108
2020	4,038
2019	809
2018	1,434
2017	2,849
Prior	1,210
Term Total	13,448
Revolving	2,956
Total	16,404
Commercial and industrial loans | Non-working capital loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2021	4,300
2020	6,734
2019	1,320
2018	4,678
2017	6,236
Prior	645
Term Total	23,913
Revolving	3,355
Total	27,268
Commercial and industrial loans | Non-working capital loans | Not Rated
Financing Receivable, Credit Quality Indicator [Line Items]
2021	1,261
2020	2,235
2019	1,004
2018	864
2017	274
Prior	44
Term Total	5,682
Revolving	0
Total	5,682
Commercial real estate and multi-family residential loans | Construction and land development loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	16,908
2020	43,152
2019	4,359
2018	57,266
2017	1,501
Prior	16,974
Term Total	140,160
Revolving	261,048
Total	401,208
Commercial real estate and multi-family residential loans | Owner occupied loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021	80,046
2020	182,150
2019	71,804
2018	85,598
2017	106,475
Prior	106,316
Term Total	632,389
Revolving	40,081
Total	672,470
Commercial real estate and multi-family residential loans | Owner occupied loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	73,686
2020	180,146
2019	68,583
2018	82,093
2017	86,853
Prior	103,342
Term Total	594,703
Revolving	40,081
Total	634,784
Commercial real estate and multi-family residential loans | Owner occupied loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2021	6,360
2020	0
2019	2,149
2018	1,399
2017	18,903
Prior	2,043
Term Total	30,854
Revolving	0
Total	30,854
Commercial real estate and multi-family residential loans | Owner occupied loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0
2020	2,004
2019	1,072
2018	2,106
2017	719
Prior	931
Term Total	6,832
Revolving	0
Total	6,832
Commercial real estate and multi-family residential loans | Nonowner occupied loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021	57,849
2020	171,157
2019	145,811
2018	44,657
2017	42,698
Prior	103,683
Term Total	565,855
Revolving	39,656
Total	605,511
Commercial real estate and multi-family residential loans | Nonowner occupied loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	50,958
2020	170,784
2019	145,168
2018	41,276
2017	42,698
Prior	83,682
Term Total	534,566
Revolving	39,656
Total	574,222
Commercial real estate and multi-family residential loans | Nonowner occupied loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2021	6,891
2020	373
2019	643
2018	0
2017	0
Prior	20,001
Term Total	27,908
Revolving	0
Total	27,908
Commercial real estate and multi-family residential loans | Nonowner occupied loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0
2020	0
2019	0
2018	3,381
2017	0
Prior	0
Term Total	3,381
Revolving	0
Total	3,381
Commercial real estate and multi-family residential loans | Multifamily loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021	35,494
2020	92,421
2019	79,132
2018	14,759
2017	39,335
Prior	24,610
Term Total	285,751
Revolving	14,338
Total	300,089
Commercial real estate and multi-family residential loans | Multifamily loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	35,494
2020	92,421
2019	79,132
2018	14,759
2017	17,083
Prior	24,610
Term Total	263,499
Revolving	14,338
Total	277,837
Commercial real estate and multi-family residential loans | Multifamily loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0
2020	0
2019	0
2018	0
2017	22,252
Prior	0
Term Total	22,252
Revolving	0
Total	22,252
Agri-business and agricultural loans | Loans secured by farmland
Financing Receivable, Credit Quality Indicator [Line Items]
2021	29,377
2020	42,164
2019	22,120
2018	16,211
2017	11,717
Prior	22,695
Term Total	144,284
Revolving	22,985
Total	167,269
Agri-business and agricultural loans | Loans secured by farmland | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	29,377
2020	39,963
2019	19,765
2018	16,211
2017	11,527
Prior	22,520
Term Total	139,363
Revolving	22,027
Total	161,390
Agri-business and agricultural loans | Loans secured by farmland | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0
2020	1,985
2019	2,355
2018	0
2017	190
Prior	30
Term Total	4,560
Revolving	958
Total	5,518
Agri-business and agricultural loans | Loans secured by farmland | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0
2020	216
2019	0
2018	0
2017	0
Prior	145
Term Total	361
Revolving	0
Total	361
Agri-business and agricultural loans | Loans for agricultural production
Financing Receivable, Credit Quality Indicator [Line Items]
2021	5,720
2020	39,954
2019	10,675
2018	30,310
2017	1,756
Prior	6,749
Term Total	95,164
Revolving	84,246
Total	179,410
Agri-business and agricultural loans | Loans for agricultural production | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	5,240
2020	31,307
2019	9,408
2018	30,310
2017	1,704
Prior	6,730
Term Total	84,699
Revolving	76,772
Total	161,471
Agri-business and agricultural loans | Loans for agricultural production | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2021	480
2020	8,647
2019	1,267
2018	0
2017	52
Prior	19
Term Total	10,465
Revolving	7,474
Total	17,939
Other commercial loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021	575
2020	29,814
2019	5,379
2018	2,419
2017	9,648
Prior	13,629
Term Total	61,464
Revolving	23,797
Total	85,261
Other commercial loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	575
2020	29,814
2019	5,379
2018	2,419
2017	9,648
Prior	9,538
Term Total	57,373
Revolving	23,797
Total	81,170
Other commercial loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0
2020	0
2019	0
2018	0
2017	0
Prior	4,091
Term Total	4,091
Revolving	0
Total	4,091
Consumer 1-4 family loans | Closed end first mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021	25,333
2020	48,298
2019	18,349
2018	19,632
2017	16,114
Prior	37,150
Term Total	164,876
Revolving	4,479
Total	169,355
Consumer 1-4 family loans | Closed end first mortgage loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	5,000
2020	18,106
2019	6,470
2018	7,046
2017	3,737
Prior	2,996
Term Total	43,355
Revolving	3,890
Total	47,245
Consumer 1-4 family loans | Closed end first mortgage loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0
2020	0
2019	0
2018	0
2017	14
Prior	3,309
Term Total	3,323
Revolving	0
Total	3,323
Consumer 1-4 family loans | Closed end first mortgage loans | Not Rated
Financing Receivable, Credit Quality Indicator [Line Items]
2021	20,333
2020	30,192
2019	11,879
2018	12,586
2017	12,363
Prior	30,845
Term Total	118,198
Revolving	589
Total	118,787
Consumer 1-4 family loans | Open end and junior lien loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021	8,565
2020	8,233
2019	8,056
2018	6,210
2017	3,136
Prior	2,134
Term Total	36,334
Revolving	127,545
Total	163,879
Consumer 1-4 family loans | Open end and junior lien loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	101
2020	452
2019	163
2018	346
2017	0
Prior	31
Term Total	1,093
Revolving	11,974
Total	13,067
Consumer 1-4 family loans | Open end and junior lien loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0
2020	0
2019	0
2018	0
2017	0
Prior	0
Term Total	0
Revolving	98
Total	98
Consumer 1-4 family loans | Open end and junior lien loans | Not Rated
Financing Receivable, Credit Quality Indicator [Line Items]
2021	8,464
2020	7,781
2019	7,893
2018	5,864
2017	3,136
Prior	2,103
Term Total	35,241
Revolving	115,473
Total	150,714
Consumer 1-4 family loans | Residential construction loans | Not Rated
Financing Receivable, Credit Quality Indicator [Line Items]
2021	5,864
2020	3,940
2019	1,028
2018	257
2017	174
Prior	1,191
Term Total	12,454
Revolving	0
Total	$ 12,454