Fair Value of Assets and Liabilities - Schedule of Quantitative Information About Significant Unobservable Inputs (Details)	6 Months Ended	12 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Servicing Assets:
Collection fee market rate	0.11%	0.10%
Prosper Funding LLC
Servicing Assets:
Collection fee market rate	0.11%	0.10%
Minimum
Servicing Assets:
Discount rate	15.00%	15.00%
Default rate	2.00%	2.00%
Prepayment rate	8.70%	13.30%
Market servicing rate	0.593%	0.593%
Weighted-average market servicing rate	0.703%	0.693%
Minimum \| Prosper Funding LLC
Servicing Assets:
Discount rate	15.00%	15.00%
Default rate	2.00%	1.90%
Prepayment rate	8.70%	3.40%
Market servicing rate	0.593%	0.593%
Weighted-average market servicing rate	0.703%	0.693%
Maximum
Servicing Assets:
Discount rate	25.00%	25.00%
Default rate	13.90%	15.00%
Prepayment rate	35.10%	35.60%
Market servicing rate	0.842%	0.842%
Weighted-average market servicing rate	0.952%	0.942%
Maximum \| Prosper Funding LLC
Servicing Assets:
Discount rate	25.00%	25.00%
Default rate	13.90%	15.00%
Prepayment rate	38.00%	41.40%
Market servicing rate	0.842%	0.842%
Weighted-average market servicing rate	0.952%	0.942%
Discount rate \| Minimum
Borrower Loans and Notes:
Fair value assumptions	0.052	0.050
Loan Trailing Fee Liability:
Fair value assumptions	0.052	0.050
Discount rate \| Minimum \| Loan trailing fee liability
Borrower Loans and Notes:
Fair value assumptions	0.150	0.150
Loan Trailing Fee Liability:
Fair value assumptions	0.150	0.150
Discount rate \| Minimum \| Prosper Funding LLC
Borrower Loans and Notes:
Fair value assumptions	0.062	0.063
Loan Trailing Fee Liability:
Fair value assumptions	0.062	0.063
Discount rate \| Minimum \| Prosper Funding LLC \| Loan trailing fee liability
Borrower Loans and Notes:
Fair value assumptions	0.150	0.150
Loan Trailing Fee Liability:
Fair value assumptions	0.150	0.150
Discount rate \| Maximum
Borrower Loans and Notes:
Fair value assumptions	0.168	0.155
Loan Trailing Fee Liability:
Fair value assumptions	0.168	0.155
Discount rate \| Maximum \| Loan trailing fee liability
Borrower Loans and Notes:
Fair value assumptions	0.250	0.250
Loan Trailing Fee Liability:
Fair value assumptions	0.250	0.250
Discount rate \| Maximum \| Prosper Funding LLC
Borrower Loans and Notes:
Fair value assumptions	0.168	0.155
Loan Trailing Fee Liability:
Fair value assumptions	0.168	0.155
Discount rate \| Maximum \| Prosper Funding LLC \| Loan trailing fee liability
Borrower Loans and Notes:
Fair value assumptions	0.250	0.250
Loan Trailing Fee Liability:
Fair value assumptions	0.250	0.250
Default rate \| Minimum
Borrower Loans and Notes:
Fair value assumptions	0.024	0.019
Loan Trailing Fee Liability:
Fair value assumptions	0.024	0.019
Default rate \| Minimum \| Loan trailing fee liability
Borrower Loans and Notes:
Fair value assumptions	0.020	0.020
Loan Trailing Fee Liability:
Fair value assumptions	0.020	0.020
Default rate \| Minimum \| Prosper Funding LLC
Borrower Loans and Notes:
Fair value assumptions	0.024	0.023
Loan Trailing Fee Liability:
Fair value assumptions	0.024	0.023
Default rate \| Minimum \| Prosper Funding LLC \| Loan trailing fee liability
Borrower Loans and Notes:
Fair value assumptions	0.020	0.019
Loan Trailing Fee Liability:
Fair value assumptions	0.020	0.019
Default rate \| Maximum
Borrower Loans and Notes:
Fair value assumptions	0.139	0.145
Loan Trailing Fee Liability:
Fair value assumptions	0.139	0.145
Default rate \| Maximum \| Loan trailing fee liability
Borrower Loans and Notes:
Fair value assumptions	0.139	0.150
Loan Trailing Fee Liability:
Fair value assumptions	0.139	0.150
Default rate \| Maximum \| Prosper Funding LLC
Borrower Loans and Notes:
Fair value assumptions	0.139	0.145
Loan Trailing Fee Liability:
Fair value assumptions	0.139	0.145
Default rate \| Maximum \| Prosper Funding LLC \| Loan trailing fee liability
Borrower Loans and Notes:
Fair value assumptions	0.139	0.150
Loan Trailing Fee Liability:
Fair value assumptions	0.139	0.150
Prepayment rate \| Minimum \| Loan trailing fee liability
Borrower Loans and Notes:
Fair value assumptions	0.087	0.133
Loan Trailing Fee Liability:
Fair value assumptions	0.087	0.133
Prepayment rate \| Minimum \| Prosper Funding LLC \| Loan trailing fee liability
Borrower Loans and Notes:
Fair value assumptions	0.087	0.034
Loan Trailing Fee Liability:
Fair value assumptions	0.087	0.034
Prepayment rate \| Maximum \| Loan trailing fee liability
Borrower Loans and Notes:
Fair value assumptions	0.351	0.356
Loan Trailing Fee Liability:
Fair value assumptions	0.351	0.356
Prepayment rate \| Maximum \| Prosper Funding LLC \| Loan trailing fee liability
Borrower Loans and Notes:
Fair value assumptions	0.380	0.414
Loan Trailing Fee Liability:
Fair value assumptions	0.380	0.414

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- Definition

Fair Value Assumptions, Collection Fee Market Rate

+ References

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Fair Value Assumptions, Weighted Average Market Servicing Rate

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- Definition

Loan Trailing Fee Liability

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- Definition

Servicing Assets

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- Definition

Value of input used to measure investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 103
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-103

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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- Definition

Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

+ 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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- Definition

Percentage of contractually collectible principal associated with a financial asset expected not to be collected due to default by the borrower.

+ References

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- Definition

Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

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