LOAN SERVICING RIGHTS - Schedule of Sensitivity of Fair Value to Adverse Changes in Model Inputs and/or Assumptions (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024	Dec. 31, 2023
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	$ 12,640,061	$ 12,454,454
Composition of residential loans serviced for others	100.00%	100.00%
Weighted average term (months) and (years)	355 months	355 months
Weighted average age (months)	29 months	27 months
Modeled prepayment speed	8.41%	8.56%
Decline in fair value due to a 10% adverse change	$ (5,424)	$ (4,492)
Decline in fair value due to a 20% adverse change	$ (11,079)	$ (9,444)
Weighted average discount rate	10.73%	10.98%
Decline in fair value due to 10% and 100 basis points adverse change	$ (6,742)	$ (5,110)
Decline in fair value due to a 20% and 200 basis points adverse change	$ (13,926)	$ (11,181)
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	17.50%	17.54%
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	50.48%	50.51%
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	32.02%	31.95%
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	$ 252,465	$ 271,164
Weighted average term (months) and (years)	3 years 2 months 4 days	3 years 3 months 21 days
Modeled prepayment speed	21.62%	20.83%
Decline in fair value due to a 10% adverse change	$ (170)	$ (171)
Decline in fair value due to a 20% adverse change	$ (324)	$ (327)
Weighted average discount rate	13.00%	14.70%
Decline in fair value due to 10% and 100 basis points adverse change	$ (66)	$ (69)
Decline in fair value due to a 20% and 200 basis points adverse change	$ (128)	$ (135)

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

No definition available.

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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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