FAIR VALUE MEASUREMENT - Schedule of Fair Value Changes and Activity for Level 3 (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Available-for-sale Securities [Member]
Fair Value Changes and Activity for Level 3 [Roll Forward]
Beginning balance	$ 2,885	$ 1,937	$ 1,952	$ 0
Additions	0	0	985	0
Transfers	0	0	0	2,379
Payoffs/Sales/Settlements	(48)	(40)	(339)	(80)
Change in mark to market/Realized/unrealized gains (losses)	24	84	263	(318)
Ending balance	2,861	1,981	2,861	1,981
Loans held for sale [Member]
Fair Value Changes and Activity for Level 3 [Roll Forward]
Beginning balance		4,525		2,691
Additions		781		2,667
Transfers		0		0
Payoffs/Sales/Settlements		(909)		(909)
Change in mark to market/Realized/unrealized gains (losses)		30		(22)
Ending balance		4,427		4,427
Loans held for investment [Member]
Fair Value Changes and Activity for Level 3 [Roll Forward]
Beginning balance	4,926	4,830	3,468	4,057
Additions	1,667	274	3,346	999
Transfers	0	0	0	0
Payoffs/Sales/Settlements	(536)	(603)	(783)	(606)
Change in mark to market/Realized/unrealized gains (losses)	(210)	(26)	(184)	25
Ending balance	5,847	4,475	5,847	4,475
Interest rate lock commitments [Member]
Fair Value Changes and Activity for Level 3 [Roll Forward]
Beginning balance	13,502	14,056	2,223	10,284
Payoffs/Sales/Settlements	(7,801)	(19,179)	(12,284)	(35,072)
Change in mark to market/Realized/unrealized gains (losses)	12,266	13,747	28,028	33,412
Ending balance	$ 17,967	$ 8,624	$ 17,967	$ 8,624

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

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- Definition

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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- Definition

Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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- Definition

Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

+ References

No definition available.

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- Definition

Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19279-110258

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