FAIR VALUE MEASUREMENT - Schedule of Fair Value Changes and Activity for Level 3 (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Interest rate lock commitments
Fair Value Changes and Activity for Level 3 [Roll Forward]
Beginning balance	$ 2,484	$ 17,392
Payoffs/Sales/Settlements	(229)	(7,435)
Change in mark to market/Realized/unrealized gains (losses)	(2,177)	(3,469)
Ending balance	78	6,488
Investment securities AFS
Fair Value Changes and Activity for Level 3 [Roll Forward]
Beginning balance	2,482	2,710
Additions	0	0
Transfers	0	0
Payoffs/Sales/Settlements	(48)	(48)
Change in mark to market/Realized/unrealized gains (losses)	(127)	(172)
Ending balance	2,307	2,490
Single family LHFI
Fair Value Changes and Activity for Level 3 [Roll Forward]
Beginning balance	7,287	7,108
Additions	0	360
Transfers	0	0
Payoffs/Sales/Settlements	0	(3,191)
Change in mark to market/Realized/unrealized gains (losses)	(306)	47
Ending balance	$ 6,981	$ 4,324

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=123874694&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=123874694&loc=d3e19207-110258

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-Name Accounting Standards Codification
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-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19279-110258

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