MORTGAGE BANKING OPERATIONS - Revenue from Mortgage Servicing (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Servicing income, net:
Servicing fees and other	$ 6,695	$ 6,405	$ 19,611	$ 19,666
Amortization of multifamily and SBA MSRs			(4,284)	(4,363)
Net servicing income	3,603	3,467	10,517	10,429
Risk management, single family MSRs:
Changes in fair value of MSRs due to assumptions	(1,963)	785	(816)	1,794
Net gain (loss) from economic hedging	1,418	(1,160)	(201)	(2,833)
Mortgage servicing rights, risk management	(545)	(375)	(1,017)	(1,039)
Loan servicing income	3,058	3,092	$ 9,500	9,390
Servicing asset at fair value, other change in fair value statement of income or comprehensive income extensible enumeration not disclosed flag			Changes in fair value of MSRs due to assumptions (2)
Interest income, securities, US treasury	300	300	$ 900	1,100
Single family
Servicing income, net:
Amortization of single family MSRs	1,669	1,564	4,810	4,874
Risk management, single family MSRs:
Changes in fair value of MSRs due to assumptions	1,963	(785)	816	(1,794)
Single family \| Residential Portfolio Segment
Servicing income, net:
Amortization of single family MSRs	(1,669)	(1,564)	(4,810)	(4,874)
Multifamily \| Residential Portfolio Segment
Servicing income, net:
Amortization of single family MSRs	$ (1,423)	$ (1,374)	$ (4,284)	$ (4,363)

Changes in the fair value of mortgage servicing rights due to modeled amortization.

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- Definition

Derivative, Gain (Loss) On Derivative, Net, And Debt Securities, Trading, Unrealized Gain (Loss)

+ References

No definition available.

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- Definition

Changes in MSR fair value due to changes in model inputs and assumptions, net of risk management derivatives.

+ References

No definition available.

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- Definition

Servicing and other related fees, net of payments.

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No definition available.

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- Definition

Risk Management, Single Family MSRs [Abstract]

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- Definition

ServicingAssetAtFairValueOtherChangeInFairValueStatementOfIncomeOrComprehensiveIncomeExtensibleEnumerationNotDisclosedFlag

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No definition available.

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- Definition

Servicing fees and other.

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No definition available.

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- Definition

Servicing Fees Net, Including Discontinued Operations

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- Definition

Servicing Income, Net [Abstract]

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No definition available.

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- Definition

The periodic amortization (in proportion to and over the period of estimated net servicing income or loss) of capitalized servicing rights, which contractually entitle the servicer to receive fees and ancillary revenues for performing billing, collection, disbursement and recordkeeping services in connection with a mortgage portfolio. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)(4)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481229/860-50-50-4

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- Definition

Interest income on US treasury securities. US treasury securities are negotiable debt obligations of the US government, secured by its full faith and credit and issued at various schedules and maturities. The income from treasury securities is exempt from state and local, but not federal, taxes. There are three types of securities issued by the US treasury (bonds, bills, and notes), which are distinguished by the amount of time from the initial sale of the bond to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

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- Definition

Amount of increase (decrease) from changes in fair value classified as other for a contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(4)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481229/860-50-50-3

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