FAIR VALUE MEASUREMENT - Schedule of Level 3 Unobservable Inputs (Details) - Fair Value, Recurring $ in Thousands	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Single family LHFI	$ 1,280	$ 5,868
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities AFS	1,860	2,009
Single family LHFI	1,280	5,868
Level 3 \| Single family
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Single family LHFI	$ 1,280	$ 5,868
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	0.0225	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	0.0330	0.0287
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	0.0225	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	0.0504	0.0515
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	0.0225	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	0.0394	0.0414
Interest rate lock commitments \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Interest rate lock commitments, net	$ 411	$ 105
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	0.0081	0.0010
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	0.4164	0.1750
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	0.1054	0.0643
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	0.0032	0.0054
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	0.0080	0.0111
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	0.0057	0.0095

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
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481830/320-10-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

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- Definition

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
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Value of input used to measure derivative asset.

+ References

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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

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-Publisher FASB
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