LOANS HELD FOR INVESTMENT, Activity in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
LOANS HELD FOR INVESTMENT [Abstract]
Percentage of allowance for loan losses to loans held for investment	1.74%		1.74%		1.13%
Allowance for Loan Losses [Roll Forward]
Beginning Balance	$ 29,074	$ 23,381	$ 24,197	$ 23,126
Provision for loan losses	13,133	875	19,367	1,483
Charge-offs	(2,013)	(546)	(3,683)	(1,215)
Recoveries	441	461	754	777
Ending Balance	40,635	24,171	40,635	24,171
Commercial Real Estate [Member]
Allowance for Loan Losses [Roll Forward]
Beginning Balance	7,192	5,335	5,049	5,579
Provision for loan losses	7,856	(28)	9,892	(379)
Charge-offs	0	0	0	0
Recoveries	108	108	215	215
Ending Balance	15,156	5,415	15,156	5,415
Commercial [Member] \| Specialized [Member]
Allowance for Loan Losses [Roll Forward]
Beginning Balance	4,555	2,327	2,287	2,516
Provision for loan losses	2,872	985	5,090	804
Charge-offs	(836)	(5)	(850)	(37)
Recoveries	23	39	87	63
Ending Balance	6,614	3,346	6,614	3,346
Commercial [Member] \| General [Member]
Allowance for Loan Losses [Roll Forward]
Beginning Balance	7,980	8,504	9,609	8,173
Provision for loan losses	1,773	(324)	975	(60)
Charge-offs	(532)	(60)	(1,380)	(65)
Recoveries	72	205	89	277
Ending Balance	9,293	8,325	9,293	8,325
Consumer [Member] \| 1-4 Family Residential [Member]
Allowance for Loan Losses [Roll Forward]
Beginning Balance	2,744	2,416	2,093	2,249
Provision for loan losses	181	(127)	832	28
Charge-offs	0	0	0	(19)
Recoveries	1	21	1	52
Ending Balance	2,926	2,310	2,926	2,310
Consumer [Member] \| Auto Loans [Member]
Allowance for Loan Losses [Roll Forward]
Beginning Balance	4,312	3,067	3,385	2,994
Provision for loan losses	(168)	202	1,149	500
Charge-offs	(262)	(248)	(704)	(506)
Recoveries	57	46	109	79
Ending Balance	3,939	3,067	3,939	3,067
Consumer [Member] \| Other Consumer [Member]
Allowance for Loan Losses [Roll Forward]
Beginning Balance	1,639	1,174	1,341	1,192
Provision for loan losses	205	216	796	429
Charge-offs	(383)	(233)	(749)	(513)
Recoveries	179	42	252	91
Ending Balance	1,640	1,199	1,640	1,199
Construction [Member]
Allowance for Loan Losses [Roll Forward]
Beginning Balance	652	558	433	423
Provision for loan losses	414	(49)	633	161
Charge-offs	0	0	0	(75)
Recoveries	1	0	1	0
Ending Balance	$ 1,067	$ 509	$ 1,067	$ 509

This element represents percentage of allowance for loan losses to loans held for investment.

No definition available.

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- Definition

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

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