FAIR VALUE OF ASSETS AND LIABILITIES - Schedule Assumptions and the Sensitivity of the Fair Value (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Servicing Assets And Liabilities Fair Value [Line Items]
Servicing Assets	$ 17,402	$ 13,718
Servicing rate increase	0.025%
Servicing rate decrease	0.025%
Prepayment rate increase	110.00%
Prepayment rate decrease	90.00%
Default rate increase	110.00%
Default rate decrease	90.00%
Prosper Funding LLC
Servicing Assets And Liabilities Fair Value [Line Items]
Servicing Assets	$ 17,601	14,333
Servicing rate increase	0.025%
Servicing rate decrease	0.025%
Prepayment rate increase	1.10%
Prepayment rate decrease	0.90%
Default rate increase	1.10%
Default rate decrease	0.90%
Prepayment rate assumption
Servicing Assets And Liabilities Fair Value [Line Items]
Prepayment rate increase	110.00%
Prepayment rate decrease	90.00%
Default rate assumption
Servicing Assets And Liabilities Fair Value [Line Items]
Default rate increase	110.00%
Default rate decrease	90.00%
Servicing Assets
Servicing Assets And Liabilities Fair Value [Line Items]
Servicing Assets	$ 17,402	13,718
Servicing Assets \| Prosper Funding LLC
Servicing Assets And Liabilities Fair Value [Line Items]
Servicing Assets	17,601	14,333
Servicing Assets \| Market servicing rate increase of 0.025% \| Market servicing rate
Servicing Assets And Liabilities Fair Value [Line Items]
Expected fair value with change in assumptions	16,398	12,843
Servicing Assets \| Market servicing rate increase of 0.025% \| Market servicing rate \| Prosper Funding LLC
Servicing Assets And Liabilities Fair Value [Line Items]
Expected fair value with change in assumptions	16,586	13,419
Servicing Assets \| Market servicing rate decrease of 0.025% \| Market servicing rate
Servicing Assets And Liabilities Fair Value [Line Items]
Expected fair value with change in assumptions	18,405	14,593
Servicing Assets \| Market servicing rate decrease of 0.025% \| Market servicing rate \| Prosper Funding LLC
Servicing Assets And Liabilities Fair Value [Line Items]
Expected fair value with change in assumptions	18,615	15,247
Servicing Assets \| Applying a 1.1 multiplier to prepayment rate \| Prepayment rate assumption
Servicing Assets And Liabilities Fair Value [Line Items]
Expected fair value with change in assumptions	16,949	13,415
Servicing Assets \| Applying a 1.1 multiplier to prepayment rate \| Prepayment rate assumption \| Prosper Funding LLC
Servicing Assets And Liabilities Fair Value [Line Items]
Expected fair value with change in assumptions	17,143	14,016
Servicing Assets \| Applying a 0.9 multiplier to prepayment rate \| Prepayment rate assumption
Servicing Assets And Liabilities Fair Value [Line Items]
Expected fair value with change in assumptions	17,863	14,026
Servicing Assets \| Applying a 0.9 multiplier to prepayment rate \| Prepayment rate assumption \| Prosper Funding LLC
Servicing Assets And Liabilities Fair Value [Line Items]
Expected fair value with change in assumptions	18,068	14,655
Servicing Assets \| Applying a 1.1 multiplier to default rate \| Default rate assumption
Servicing Assets And Liabilities Fair Value [Line Items]
Expected fair value with change in assumptions	17,114	13,448
Servicing Assets \| Applying a 1.1 multiplier to default rate \| Default rate assumption \| Prosper Funding LLC
Servicing Assets And Liabilities Fair Value [Line Items]
Expected fair value with change in assumptions	17,310	14,052
Servicing Assets \| Applying a 0.9 multiplier to default rate \| Default rate assumption
Servicing Assets And Liabilities Fair Value [Line Items]
Expected fair value with change in assumptions	17,689	13,989
Servicing Assets \| Applying a 0.9 multiplier to default rate \| Default rate assumption \| Prosper Funding LLC
Servicing Assets And Liabilities Fair Value [Line Items]
Expected fair value with change in assumptions	$ 17,892	$ 14,616
Servicing Assets \| Market servicing rate
Servicing Assets And Liabilities Fair Value [Line Items]
Valuation techniques	0.598%	0.64%
Servicing Assets \| Market servicing rate \| Prosper Funding LLC
Servicing Assets And Liabilities Fair Value [Line Items]
Valuation techniques	0.598%	0.635%
Servicing Assets \| Prepayment rate
Servicing Assets And Liabilities Fair Value [Line Items]
Valuation techniques	21.65%	18.70%
Servicing Assets \| Prepayment rate \| Prosper Funding LLC
Servicing Assets And Liabilities Fair Value [Line Items]
Valuation techniques	21.72%	18.83%
Servicing Assets \| Default rate
Servicing Assets And Liabilities Fair Value [Line Items]
Valuation techniques	11.84%	14.03%
Servicing Assets \| Default rate \| Prosper Funding LLC
Servicing Assets And Liabilities Fair Value [Line Items]
Valuation techniques	11.86%	13.89%

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