LOANS HELD FOR INVESTMENT, Investment in loans Disaggregated Based on Method of Evaluating Impairment (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Recorded Investment [Abstract]
Individually Evaluated	$ 13,646	$ 4,167
Collectively Evaluated	2,274,588	2,139,456
Allowance for Loan Losses [Abstract]
Individually Evaluated	2,064	525
Collectively Evaluated	44,012	23,672
Commercial Real Estate [Member]
Recorded Investment [Abstract]
Individually Evaluated	4,339	299
Collectively Evaluated	651,093	657,896
Allowance for Loan Losses [Abstract]
Individually Evaluated	260	0
Collectively Evaluated	18,004	5,049
Commercial [Member] \| Specialized [Member]
Recorded Investment [Abstract]
Individually Evaluated	0	573
Collectively Evaluated	340,458	308,932
Allowance for Loan Losses [Abstract]
Individually Evaluated	0	0
Collectively Evaluated	6,304	2,287
Commercial [Member] \| General [Member]
Recorded Investment [Abstract]
Individually Evaluated	7,071	1,396
Collectively Evaluated	571,110	440,002
Allowance for Loan Losses [Abstract]
Individually Evaluated	1,734	525
Collectively Evaluated	8,255	9,084
Consumer [Member] \| 1-4 Family Residential [Member]
Recorded Investment [Abstract]
Individually Evaluated	2,236	1,899
Collectively Evaluated	369,878	360,897
Allowance for Loan Losses [Abstract]
Individually Evaluated	70	0
Collectively Evaluated	4,614	2,093
Consumer [Member] \| Auto Loans [Member]
Recorded Investment [Abstract]
Individually Evaluated	0	0
Collectively Evaluated	193,023	215,209
Allowance for Loan Losses [Abstract]
Individually Evaluated	0	0
Collectively Evaluated	4,233	3,385
Consumer [Member] \| Other Consumer [Member]
Recorded Investment [Abstract]
Individually Evaluated	0	0
Collectively Evaluated	68,877	74,000
Allowance for Loan Losses [Abstract]
Individually Evaluated	0	0
Collectively Evaluated	1,727	1,341
Construction [Member]
Recorded Investment [Abstract]
Individually Evaluated	0	0
Collectively Evaluated	80,149	82,520
Allowance for Loan Losses [Abstract]
Individually Evaluated	0	0
Collectively Evaluated	$ 875	$ 433

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

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- References

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