FAIR VALUE MEASUREMENT - Schedule of Level 3 Unobservable Inputs (Details) - Fair Value, Recurring $ in Thousands	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Single family LHFI	$ 5,868	$ 7,287
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities AFS	2,009	2,482
Single family LHFI	5,868	7,287
Level 3 \| Single Family
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Single family LHFI	$ 5,868	$ 7,287
Implied spread to benchmark interest rate curve \| Level 3 \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities available for sale, measurement input	0.0200	0.0200
Implied spread to benchmark interest rate curve \| Level 3 \| Minimum \| Single Family
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Single family LHFI, measurement input	0.0287	0.0239
Implied spread to benchmark interest rate curve \| Level 3 \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities available for sale, measurement input	0.0200	0.0200
Implied spread to benchmark interest rate curve \| Level 3 \| Maximum \| Single Family
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Single family LHFI, measurement input	0.0515	0.0796
Implied spread to benchmark interest rate curve \| Level 3 \| Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities available for sale, measurement input	0.0200	0.0200
Implied spread to benchmark interest rate curve \| Level 3 \| Weighted Average \| Single Family
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Single family LHFI, measurement input	0.0414	0.0356
Interest rate lock commitments \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Interest rate lock commitments, net	$ 105	$ 2,484
Interest rate lock commitments \| Fall-out factor \| Level 3 \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Interest rate lock commitments, net, measurement input	0.0010	0.0015
Interest rate lock commitments \| Fall-out factor \| Level 3 \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Interest rate lock commitments, net, measurement input	0.1750	0.2193
Interest rate lock commitments \| Fall-out factor \| Level 3 \| Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Interest rate lock commitments, net, measurement input	0.0643	0.0844
Interest rate lock commitments \| Value of servicing \| Level 3 \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Interest rate lock commitments, net, measurement input	0.0054	0.0035
Interest rate lock commitments \| Value of servicing \| Level 3 \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Interest rate lock commitments, net, measurement input	0.0111	0.0146
Interest rate lock commitments \| Value of servicing \| Level 3 \| Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Interest rate lock commitments, net, measurement input	0.0095	0.0115

Loans Held-for-Investment, Measurement Input

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
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-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
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Value of input used to measure investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ 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 (bbb)(2)
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- Definition

Value of input used to measure derivative asset.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ 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

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI https://asc.fasb.org/subtopic&trid=2196772

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