LOAN SERVICING RIGHTS - Schedule of Sensitivity of Fair Value to Adverse Changes in Model Inputs and/or Assumptions (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2023	Dec. 31, 2022
Residential mortgage
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Unpaid principal balance of loans serviced for others	$ 12,013,844	$ 10,046,052
Composition of residential loans serviced for others:	100.00%	100.00%
Weighted average term (months)	354 months	353 months
Weighted average age (months)	26 months	22 months
Modeled prepayment speed	7.79%	8.22%
Decline in fair value due to a 10% adverse change	$ (2,900)	$ (5,800)
Decline in fair value due to a 20% adverse change	$ (6,483)	$ (11,184)
Weighted average discount rate	11.66%	10.00%
Decline in fair value due to a 10% adverse change	$ (3,843)	$ (6,413)
Decline in fair value due to a 20% adverse change	$ (8,989)	$ (12,330)
Residential mortgage \| FHLMC
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Composition of residential loans serviced for others:	17.41%	16.80%
Residential mortgage \| FNMA
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Composition of residential loans serviced for others:	50.44%	50.09%
Residential mortgage \| GNMA
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Composition of residential loans serviced for others:	32.15%	33.11%
SBA servicing rights
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Unpaid principal balance of loans serviced for others	$ 299,910	$ 326,418
Weighted average term (months)	3 years 5 months 26 days	3 years 8 months 8 days
Modeled prepayment speed	19.68%	18.24%
Decline in fair value due to a 10% adverse change	$ (265)	$ (177)
Decline in fair value due to a 20% adverse change	$ (415)	$ (340)
Weighted average discount rate	16.97%	19.57%
Decline in fair value due to a 10% adverse change	$ (170)	$ (83)
Decline in fair value due to a 20% adverse change	$ (236)	$ (163)

Loans Serviced For Others, Percentage

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- Definition

Servicing Assets And Servicing Liabilities At Fair Value, Assumptions Used To Estimate Fair Value, Weighted Average Age

+ References

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- Definition

This is the sum of principal amount outstanding for both securitized and unsecuritized loans of all types.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Subparagraph (a)
-Paragraph 4
-SubTopic 20
-Topic 860
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481326/860-20-50-4

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- Definition

The hypothetical financial impact of a 10 percent adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 860
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481326/860-20-50-4

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- Definition

The hypothetical financial impact of a 10 percent adverse change of prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

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- Definition

The hypothetical financial impact of a 20 percent adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

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The hypothetical financial impact of a 20 percent adverse change of prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481326/860-20-50-4

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- Definition

A specified percentage variance in the discount rate assumption in the determination of fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

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A specified percentage variance in the prepayment speed assumption in the determination of fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities).

+ References

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- Definition

Weighted average life of financial assets and financial liabilities, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481229/860-50-50-2

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