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Fair value of options vested during period Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested in Period, Fair Value Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Operating lease liability and right-of-use asset Increase (Decrease) In Operating Lease Liability And Right of Use Asset Increase (Decrease) In Operating Lease Liability And Right of Use Asset Entity Small Business Entity Small Business Sales and marketing Selling and Marketing Expense [Member] Income Tax Disclosure [Abstract] Document Transition Report Document Transition Report Settlements of beneficial interest liabilities, net Payments On Beneficial Interest Liabilities Payments On Beneficial Interest Liabilities Underlying Securities Award Underlying Securities Amount Equity Component [Domain] Equity Component [Domain] Document Period End Date Document Period End Date Income Taxes Income Tax Disclosure [Text Block] Common stock Common Class A [Member] Commitments to fund future advances Contractual Obligation Trailing fee liability (at fair value) Trailing Fee Liability At Fair Value, Amount Trailing Fee Liability At Fair Value, Amount Schedule of Servicing Liabilities at Fair Value Rollforward Schedule of Servicing Liabilities at Fair Value [Table Text Block] Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Options exercisable Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Borrower fees Borrower Fees [Member] Borrower Fees Reduction in lease liability Increase (Decrease) in Operating Lease Liability Average cost (in dollars per share) Shares Acquired, Average Cost Per Share Loan Servicing Liabilities Loan Servicing Liabilities [Member] Loan Servicing Liabilities Document Type Document Type Fair Value, Inputs, Level 3 Fair Value, Inputs, Level 3 [Member] Net Income (Loss) Per Share Earnings Per Share 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