LOANS HELD FOR INVESTMENT, Impaired Loan Information (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Impaired Loan Information [Abstract]
Unpaid Contractual Principal Balance	$ 8,091	$ 13,440
Recorded Investment [Abstract]
Recorded Investment With No Allowance	3,075	9,159
Recorded Investment With Allowance	5,016	3,862
Total Recorded Investment	8,091	13,021
Related Allowance	806	1,095
Average Recorded Investment	10,557	9,894
Minimum [Member]
Recorded Investment [Abstract]
Threshold balance of loan to be specifically reviewed for impairment	250
Commercial Real Estate [Member]
Impaired Loan Information [Abstract]
Unpaid Contractual Principal Balance	1,741	6,273
Recorded Investment [Abstract]
Recorded Investment With No Allowance	1,741	3,673
Recorded Investment With Allowance	0	2,600
Total Recorded Investment	1,741	6,273
Related Allowance	0	580
Average Recorded Investment	4,007	3,666
Commercial [Member] \| Specialized [Member]
Impaired Loan Information [Abstract]
Unpaid Contractual Principal Balance	0	0
Recorded Investment [Abstract]
Recorded Investment With No Allowance	0	0
Recorded Investment With Allowance	0	0
Total Recorded Investment	0	0
Related Allowance	0	0
Average Recorded Investment	0	673
Commercial [Member] \| General [Member]
Impaired Loan Information [Abstract]
Unpaid Contractual Principal Balance	5,115	4,626
Recorded Investment [Abstract]
Recorded Investment With No Allowance	398	3,364
Recorded Investment With Allowance	4,717	1,262
Total Recorded Investment	5,115	4,626
Related Allowance	763	515
Average Recorded Investment	4,871	3,400
Consumer [Member] \| 1-4 Family Residential [Member]
Impaired Loan Information [Abstract]
Unpaid Contractual Principal Balance	1,235	2,541
Recorded Investment [Abstract]
Recorded Investment With No Allowance	936	2,122
Recorded Investment With Allowance	299	0
Total Recorded Investment	1,235	2,122
Related Allowance	43	0
Average Recorded Investment	1,679	2,155
Consumer [Member] \| Auto Loans [Member]
Impaired Loan Information [Abstract]
Unpaid Contractual Principal Balance	0	0
Recorded Investment [Abstract]
Recorded Investment With No Allowance	0	0
Recorded Investment With Allowance	0	0
Total Recorded Investment	0	0
Related Allowance	0	0
Average Recorded Investment	0	0
Consumer [Member] \| Other Consumer [Member]
Impaired Loan Information [Abstract]
Unpaid Contractual Principal Balance	0	0
Recorded Investment [Abstract]
Recorded Investment With No Allowance	0	0
Recorded Investment With Allowance	0	0
Total Recorded Investment	0	0
Related Allowance	0	0
Average Recorded Investment	0	0
Construction [Member]
Impaired Loan Information [Abstract]
Unpaid Contractual Principal Balance	0	0
Recorded Investment [Abstract]
Recorded Investment With No Allowance	0	0
Recorded Investment With Allowance	0	0
Total Recorded Investment	0	0
Related Allowance	0	0
Average Recorded Investment	$ 0	$ 0

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The amount of threshold balance of loan to be specifically reviewed for impairment.

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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