FAIR VALUE MEASUREMENTS - Schedule of Inputs Used In Valuing Residential Mortgage Loans, Consumer Loans, Mortgage Loans Receivable, Derivatives, and Asset-Backed Securities Issued (Details) $ in Thousands	Jun. 30, 2024 USD ($) security
Residential mortgage loans HFI, at fair value
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans, held-for-investment, fair value	$ 368,866
Residential mortgage loans HFI, at fair value | Minimum | Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held for investment, measurement input	0.082
Residential mortgage loans HFI, at fair value | Minimum | Prepayment Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held for investment, measurement input	0.030
Residential mortgage loans HFI, at fair value | Minimum | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held for investment, measurement input	0.014
Residential mortgage loans HFI, at fair value | Minimum | Loss Severity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held for investment, measurement input	0.149
Residential mortgage loans HFI, at fair value | Maximum | Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held for investment, measurement input	0.093
Residential mortgage loans HFI, at fair value | Maximum | Prepayment Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held for investment, measurement input	0.051
Residential mortgage loans HFI, at fair value | Maximum | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held for investment, measurement input	0.061
Residential mortgage loans HFI, at fair value | Maximum | Loss Severity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held for investment, measurement input	0.480
Residential mortgage loans HFI, at fair value | Weighted Average | Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held for investment, measurement input	0.085
Residential mortgage loans HFI, at fair value | Weighted Average | Prepayment Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held for investment, measurement input	0.042
Residential mortgage loans HFI, at fair value | Weighted Average | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held for investment, measurement input	0.039
Residential mortgage loans HFI, at fair value | Weighted Average | Loss Severity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held for investment, measurement input	0.408
Consumer Loans Held-for-Investment, At Fair Value
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans	$ 946,367
Consumer Loans Held-for-Investment, At Fair Value | SpringCastle
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans	244,578
Consumer Loans Held-for-Investment, At Fair Value | Marcus
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans	$ 701,789
Consumer Loans Held-for-Investment, At Fair Value | Minimum | Discount Rate | SpringCastle
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans, held-for-investment, measurement input	0.092
Consumer Loans Held-for-Investment, At Fair Value | Minimum | Prepayment Rate | SpringCastle
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans, held-for-investment, measurement input	0.098
Consumer Loans Held-for-Investment, At Fair Value | Minimum | Delinquency | SpringCastle
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans, held-for-investment, measurement input	0.028
Consumer Loans Held-for-Investment, At Fair Value | Minimum | Loss Severity | SpringCastle
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans, held-for-investment, measurement input	0.870
Consumer Loans Held-for-Investment, At Fair Value | Maximum | Discount Rate | SpringCastle
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans, held-for-investment, measurement input	0.102
Consumer Loans Held-for-Investment, At Fair Value | Maximum | Prepayment Rate | SpringCastle
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans, held-for-investment, measurement input	0.366
Consumer Loans Held-for-Investment, At Fair Value | Maximum | Delinquency | SpringCastle
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans, held-for-investment, measurement input	0.080
Consumer Loans Held-for-Investment, At Fair Value | Maximum | Loss Severity | SpringCastle
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans, held-for-investment, measurement input	1.000
Consumer Loans Held-for-Investment, At Fair Value | Weighted Average | Discount Rate | SpringCastle
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans, held-for-investment, measurement input	0.094
Consumer Loans Held-for-Investment, At Fair Value | Weighted Average | Discount Rate | Marcus
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans, held-for-investment, measurement input	0.077
Consumer Loans Held-for-Investment, At Fair Value | Weighted Average | Prepayment Rate | SpringCastle
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans, held-for-investment, measurement input	0.148
Consumer Loans Held-for-Investment, At Fair Value | Weighted Average | Prepayment Rate | Marcus
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans, held-for-investment, measurement input	0.208
Consumer Loans Held-for-Investment, At Fair Value | Weighted Average | Delinquency | SpringCastle
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans, held-for-investment, measurement input	0.052
Consumer Loans Held-for-Investment, At Fair Value | Weighted Average | Delinquency | Marcus
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans, held-for-investment, measurement input	0.126
Consumer Loans Held-for-Investment, At Fair Value | Weighted Average | Loss Severity | SpringCastle
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans, held-for-investment, measurement input	0.939
Consumer Loans Held-for-Investment, At Fair Value | Weighted Average | Loss Severity | Marcus
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Consumer loans, held-for-investment, measurement input	0.753
Mortgage Loans Held-for-Investment, at Fair Value
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans, held-for-investment, fair value	$ 2,049,266
IRLCs
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative, fair value	$ 16,411
IRLCs | Minimum | Loan Funding Probability
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative, measurement input	0.000
IRLCs | Minimum | Fair Value of Initial Servicing Rights (Bps)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative, measurement input	0.00092
IRLCs | Maximum | Loan Funding Probability
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative, measurement input	1.000
IRLCs | Maximum | Fair Value of Initial Servicing Rights (Bps)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative, measurement input	0.03450
IRLCs | Weighted Average | Loan Funding Probability
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative, measurement input	0.856
IRLCs | Weighted Average | Fair Value of Initial Servicing Rights (Bps)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative, measurement input	0.02429
Asset-Backed Securities Issued
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities, fair value	$ 205,286
Asset-Backed Securities Issued | Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities, measurement input	0.058
Asset-Backed Securities Issued | Prepayment Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities, measurement input	0.148
Asset-Backed Securities Issued | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities, measurement input	0.052
Asset-Backed Securities Issued | Loss Severity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities, measurement input	0.936
Acquired loans | Mortgage Loans Held-for-Investment, at Fair Value
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans, held-for-investment, fair value	$ 49,478
Acquired loans | Mortgage Loans Held-for-Investment, at Fair Value | Minimum | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans, held-for-investment, measurement input	0.018
Acquired loans | Mortgage Loans Held-for-Investment, at Fair Value | Maximum | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans, held-for-investment, measurement input	0.025
Acquired loans | Mortgage Loans Held-for-Investment, at Fair Value | Weighted Average | Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans, held-for-investment, measurement input	0.106
Acquired loans | Mortgage Loans Held-for-Investment, at Fair Value | Weighted Average | Prepayment Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans, held-for-investment, measurement input	0
Acquired loans | Mortgage Loans Held-for-Investment, at Fair Value | Weighted Average | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans, held-for-investment, measurement input	0.019
Acquired loans | Mortgage Loans Held-for-Investment, at Fair Value | Weighted Average | Loss Severity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans, held-for-investment, measurement input	0.250
Originated Loans | Mortgage Loans Held-for-Investment, at Fair Value
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans, held-for-investment, fair value	$ 1,999,788
Originated Loans | Mortgage Loans Held-for-Investment, at Fair Value | Weighted Average | Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans, held-for-investment, measurement input	0.092
Performing loans | Acquired loans | Residential mortgage loans HFS, at fair value
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, fair value	$ 13,970
Performing loans | Acquired loans | Residential mortgage loans HFS, at fair value | Minimum | Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input	0.082
Performing loans | Acquired loans | Residential mortgage loans HFS, at fair value | Minimum | Prepayment Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input	0.033
Performing loans | Acquired loans | Residential mortgage loans HFS, at fair value | Minimum | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input	0.013
Performing loans | Acquired loans | Residential mortgage loans HFS, at fair value | Minimum | Loss Severity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input	0.147
Performing loans | Acquired loans | Residential mortgage loans HFS, at fair value | Maximum | Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input	0.086
Performing loans | Acquired loans | Residential mortgage loans HFS, at fair value | Maximum | Prepayment Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input	0.051
Performing loans | Acquired loans | Residential mortgage loans HFS, at fair value | Maximum | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input	0.061
Performing loans | Acquired loans | Residential mortgage loans HFS, at fair value | Maximum | Loss Severity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input	0.480
Performing loans | Acquired loans | Residential mortgage loans HFS, at fair value | Weighted Average | Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input	0.083
Performing loans | Acquired loans | Residential mortgage loans HFS, at fair value | Weighted Average | Prepayment Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input	0.038
Performing loans | Acquired loans | Residential mortgage loans HFS, at fair value | Weighted Average | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input	0.030
Performing loans | Acquired loans | Residential mortgage loans HFS, at fair value | Weighted Average | Loss Severity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input	0.400
Non-performing loans | Acquired loans | Residential mortgage loans HFS, at fair value
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, fair value	$ 1,751
Non-performing loans | Acquired loans | Residential mortgage loans HFS, at fair value | Weighted Average | Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input	0.093
Non-performing loans | Acquired loans | Residential mortgage loans HFS, at fair value | Weighted Average | Prepayment Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input	0.187
Non-performing loans | Acquired loans | Residential mortgage loans HFS, at fair value | Weighted Average | Delinquency
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input | security	0.014
Non-performing loans | Acquired loans | Residential mortgage loans HFS, at fair value | Weighted Average | Loss Severity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input	3.250