ALLOWANCE FOR CREDIT LOSSES - Loans by risk grades and loan class (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Amortized cost of loans by loan type
Total gross loans	$ 2,888,978	$ 2,876,427
Pass
Amortized cost of loans by loan type
Total gross loans	2,804,237	2,783,385
Special Mention
Amortized cost of loans by loan type
Total gross loans	4,281	12,807
Substandard
Amortized cost of loans by loan type
Total gross loans	80,460	80,235
Commercial and industrial
Amortized cost of loans by loan type
Total gross loans	600,990	634,384
Commercial and industrial | Loans by risk grades
Amortized cost of loans by loan type
Total gross loans	600,990	634,384
Commercial and industrial | Pass
Amortized cost of loans by loan type
Total gross loans	579,987	613,419
Commercial and industrial | Special Mention
Amortized cost of loans by loan type
Total gross loans	2,934	3,482
Commercial and industrial | Substandard
Amortized cost of loans by loan type
Total gross loans	18,069	17,483
Commercial real estate
Amortized cost of loans by loan type
Total gross loans	1,142,646	1,091,969
Commercial real estate | Loans by risk grades
Amortized cost of loans by loan type
Total gross loans	1,142,646	1,091,969
Commercial real estate | Pass
Amortized cost of loans by loan type
Total gross loans	1,097,321	1,038,401
Commercial real estate | Special Mention
Amortized cost of loans by loan type
Total gross loans	879	8,855
Commercial real estate | Substandard
Amortized cost of loans by loan type
Total gross loans	44,446	44,713
Construction and development
Amortized cost of loans by loan type
Total gross loans	473,326	460,719
Construction and development | Loans by risk grades
Amortized cost of loans by loan type
Total gross loans	473,326	460,719
Construction and development | Pass
Amortized cost of loans by loan type
Total gross loans	460,165	447,533
Construction and development | Special Mention
Amortized cost of loans by loan type
Total gross loans	468	470
Construction and development | Substandard
Amortized cost of loans by loan type
Total gross loans	12,693	12,716
1-4 family residential
Amortized cost of loans by loan type
Total gross loans	263,213	277,273
1-4 family residential | Loans by risk grades
Amortized cost of loans by loan type
Total gross loans	263,213	277,273
1-4 family residential | Pass
Amortized cost of loans by loan type
Total gross loans	258,246	272,217
1-4 family residential | Substandard
Amortized cost of loans by loan type
Total gross loans	4,967	5,056
Multifamily residential
Amortized cost of loans by loan type
Total gross loans	279,099	286,396
Multifamily residential | Loans by risk grades
Amortized cost of loans by loan type
Total gross loans	279,099	286,396
Multifamily residential | Pass
Amortized cost of loans by loan type
Total gross loans	279,099	286,396
Consumer
Amortized cost of loans by loan type
Total gross loans	28,230	28,090
Consumer | Loans by risk grades
Amortized cost of loans by loan type
Total gross loans	28,230	28,090
Consumer | Pass
Amortized cost of loans by loan type
Total gross loans	28,011	27,865
Consumer | Substandard
Amortized cost of loans by loan type
Total gross loans	219	225
Agriculture
Amortized cost of loans by loan type
Total gross loans	6,287	7,941
Agriculture | Loans by risk grades
Amortized cost of loans by loan type
Total gross loans	6,287	7,941
Agriculture | Pass
Amortized cost of loans by loan type
Total gross loans	6,221	7,899
Agriculture | Substandard
Amortized cost of loans by loan type
Total gross loans	66	42
Other
Amortized cost of loans by loan type
Total gross loans	95,187	$ 89,655
Other | Pass
Amortized cost of loans by loan type
Total gross loans	$ 95,187