LOANS HELD FOR INVESTMENT, Activity in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
LOANS HELD FOR INVESTMENT [Abstract]
Percentage of allowance for loan losses to loans held for investment	1.87%		1.87%		2.05%
Allowance for Loan Losses [Roll Forward]
Beginning Balance	$ 45,019	$ 29,074	$ 45,553	$ 24,197
Provision for loan losses	(2,007)	13,133	(1,918)	19,367
Charge-offs	(297)	(2,013)	(1,138)	(3,683)
Recoveries	248	441	466	754
Ending Balance	42,963	40,635	42,963	40,635
Commercial Real Estate [Member]
Allowance for Loan Losses [Roll Forward]
Beginning Balance	19,020	7,192	18,962	5,049
Provision for loan losses	(1,732)	7,856	(1,674)	9,892
Charge-offs	0	0	0	0
Recoveries	0	108	0	215
Ending Balance	17,288	15,156	17,288	15,156
Commercial [Member] | Specialized [Member]
Allowance for Loan Losses [Roll Forward]
Beginning Balance	5,458	4,555	5,760	2,287
Provision for loan losses	(653)	2,872	(1,032)	5,090
Charge-offs	(5)	(836)	(5)	(850)
Recoveries	23	23	100	87
Ending Balance	4,823	6,614	4,823	6,614
Commercial [Member] | General [Member]
Allowance for Loan Losses [Roll Forward]
Beginning Balance	8,979	7,980	9,227	9,609
Provision for loan losses	(83)	1,773	(32)	975
Charge-offs	(34)	(532)	(377)	(1,380)
Recoveries	86	72	130	89
Ending Balance	8,948	9,293	8,948	9,293
Consumer [Member] | 1-4 Family Residential [Member]
Allowance for Loan Losses [Roll Forward]
Beginning Balance	4,890	2,744	4,646	2,093
Provision for loan losses	172	181	467	832
Charge-offs	0	0	(52)	0
Recoveries	2	1	3	1
Ending Balance	5,064	2,926	5,064	2,926
Consumer [Member] | Auto Loans [Member]
Allowance for Loan Losses [Roll Forward]
Beginning Balance	3,891	4,312	4,226	3,385
Provision for loan losses	13	(168)	(167)	1,149
Charge-offs	(139)	(262)	(327)	(704)
Recoveries	50	57	83	109
Ending Balance	3,815	3,939	3,815	3,939
Consumer [Member] | Other Consumer [Member]
Allowance for Loan Losses [Roll Forward]
Beginning Balance	1,480	1,639	1,671	1,341
Provision for loan losses	(12)	205	(6)	796
Charge-offs	(119)	(383)	(377)	(749)
Recoveries	85	179	146	252
Ending Balance	1,434	1,640	1,434	1,640
Construction [Member]
Allowance for Loan Losses [Roll Forward]
Beginning Balance	1,301	652	1,061	433
Provision for loan losses	288	414	526	633
Charge-offs	0	0	0	0
Recoveries	2	1	4	1
Ending Balance	$ 1,591	$ 1,067	$ 1,591	$ 1,067