LOANS HELD FOR INVESTMENT, COVID-19 Related Deferral and Modification (Details) $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($) Loan	Dec. 31, 2019 USD ($)
CARES Act [Abstract]
Troubled debt restructurings	$ 0	$ 0
Covid-19 [Member]
CARES Act [Abstract]
Percentage of loans modified under CARES Act	2.10%
Number of outstanding loans subject to deferral and modification agreements \| Loan	19
Amount of outstanding loans subject to deferral and modification agreements	$ 48,800
Covid-19 [Member] \| Short-term Deferral Modification Program [Member]
CARES Act [Abstract]
Amount of loans modified under CARES Act	$ 415,600
Percentage of loans modified under CARES Act	17.80%
Commercial [Member] \| Covid-19 [Member] \| Short-term Deferral Modification Program [Member] \| Interest-Only Payment [Member]
CARES Act [Abstract]
Amount of loans modified under CARES Act	$ 298,100
Period of loan modification	6 months
Commercial [Member] \| Covid-19 [Member] \| Short-term Deferral Modification Program [Member] \| Payment Deferrals [Member]
CARES Act [Abstract]
Amount of loans modified under CARES Act	$ 68,100
Period of loan modification	90 days
Consumer [Member] \| Covid-19 [Member] \| Short-term Deferral Modification Program [Member] \| Payment Deferrals [Member]
CARES Act [Abstract]
Amount of loans modified under CARES Act	$ 49,400
Consumer [Member] \| Covid-19 [Member] \| Short-term Deferral Modification Program [Member] \| Payment Deferrals [Member] \| Minimum [Member]
CARES Act [Abstract]
Period of loan modification	1 month
Consumer [Member] \| Covid-19 [Member] \| Short-term Deferral Modification Program [Member] \| Payment Deferrals [Member] \| Maximum [Member]
CARES Act [Abstract]
Period of loan modification	4 months

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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