Reclassification [Line Items]
Reclassification [Line Items]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Options vested and expected to vest
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term
Adjustments to reconcile net loss to net cash provided by operating activities:
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]
Stock repurchase program, remaining authorized repurchase amount (in dollars per share)
Share Repurchase Program, Remaining Authorized, Amount
Cover [Abstract]
Payable to investors
Increase (Decrease) In Payable To Investors
Increase (Decrease) In Payable To Investors
Change in cash and restricted cash
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect
Expected reduction in workforce, number of employees
Restructuring and Related Cost, Expected Number of Positions Eliminated
Discount rate
Measurement Input, Discount Rate [Member]
Schedule of Future Minimum Lease Payments
Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block]
Principal payments received for notes receivable and repayments of residual certificates
Proceeds from Collection of Notes Receivable
Trading Symbol
Trading Symbol
Receivables
Accrued Fees and Other Revenue Receivable
Pledged Status [Domain]
Pledged Status [Domain]
Non-NEOs
Non-NEOs [Member]
Loan premium and loan trailing fees recognized
Loan Premium Fees and Loan Trailing Fees
Loan Premium Fees and Loan Trailing Fees
10% adverse change
Sensitivity Analysis of Fair Value, Assets, Impact of 10 Percent Adverse Change in Expected Credit Loss Rates
Sensitivity Analysis of Fair Value, Assets, Impact of 10 Percent Adverse Change in Expected Credit Loss Rates
Other notes receivable
Line Of Credit Receivable, Measurement Input
Line Of Credit Receivable, Measurement Input
Line of Credit Facility [Table]
Line of Credit Facility [Table]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table]
Non-Rule 10b5-1 Arrangement Adopted
Non-Rule 10b5-1 Arrangement Adopted [Flag]
Prepayment rate
Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Prepayment Speed
Issuance of common stock upon settlement of restricted stock units (in shares)
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures
Fair Value Measurement
Fair Value Disclosures [Text Block]
Proceeds from exercise of stock options
Proceeds from Stock Options Exercised
Award Timing Disclosures [Line Items]
Financial Asset, Period Past Due [Axis]
Financial Asset, Aging [Axis]
Financing Receivable, Past Due [Table]
Financing Receivable, Past Due [Table]
Total interest income, interest expense, and fair value adjustments, net
Interest Income (Expense), Operating
200 basis point increase
Sensitivity Analysis of Fair Value, Assets, Impact of 200 Basis Point Increase In Discount Rates
Sensitivity Analysis of Fair Value, Assets, Impact of 200 Basis Point Increase In Discount Rates
Revenue from Contract with Customer [Abstract]
Plan Name [Domain]
Plan Name [Domain]
Adjustment
Revision of Prior Period, Reclassification, Adjustment [Member]
Principal payments received for loans held by consolidated securitization
Proceeds from Securitization, Loan, Held-for-Sale
Accrued payroll
Employee-related Liabilities
Leases [Abstract]
Pledged Status [Axis]
Pledged Status [Axis]
Gross Carrying Value
Finite-Lived Intangible Assets, Gross
Variable Interest Entities
Variable Interest Entity Disclosure [Text Block]
Antidilutive Securities, Name [Domain]
Antidilutive Securities, Name [Domain]
Class of Financing Receivable [Domain]
Class of Financing Receivable [Domain]
Interest rate caps
Interest Rate Derivative Assets, at Fair Value
Proceeds from convertible notes issuance, net of debt issuance costs paid to lender
Issuance of 2029 Notes
Proceeds from Convertible Debt
Receivable Type [Axis]
Receivable Type [Axis]
Net cash provided by operating activities
Net Cash Provided by (Used in) Operating Activities
2025
Long-term and Short-term Debt, Maturity, Year One
Long-term and Short-term Debt, Maturity, Year One
Cash flows from operating activities
Net Cash Provided by (Used in) Operating Activities [Abstract]
Loans Held-for- Sale
Loan Held For Sale [Member]
Loan Held For Sale
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Award Timing Method
Award Timing Method [Text Block]
Trading Arrangements, by Individual
Trading Arrangements, by Individual [Table]
Restructuring Type [Axis]
Restructuring Type [Axis]
Entity Common Stock, Shares Outstanding
Entity Common Stock, Shares Outstanding
Loans Held in Consolidated Securitization
Loans Held-for-Sale In Consolidated Securitization [Member]
Loans Held-for-Sale In Consolidated Securitization
Insider Trading Policies and Procedures [Line Items]
Use of Estimates
Use of Estimates, Policy [Policy Text Block]
Assets pledged as collateral
Debt Instrument, Collateral Amount
Adjustment to Compensation, Amount
Adjustment to Compensation Amount
Amounts received from borrowers for previously charged-off loan
Proceeds, Financing Receivable, Previously Written off, Recovery
Compensation Amount
Outstanding Recovery Compensation Amount
Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table
Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member]
Payable to investors
Repayment To Investors
Repayment To Investors
Entity Small Business
Entity Small Business
Company Selected Measure Amount
Company Selected Measure Amount
Payment of debt issuance costs to third party
Payments of Debt Issuance Costs
Accrued expenses and other liabilities at fair value
Accrued Expenses And Other Liabilities, Fair Value Disclosure
Accrued Expenses And Other Liabilities, Fair Value Disclosure
Tabular List, Table
Tabular List [Table Text Block]
Fair Value, Inputs, Level 3
Fair Value, Inputs, Level 3 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Schedule of Stock Option Activity
Schedule of Stock Options Roll Forward [Table Text Block]
Fair Value Measurement Inputs and Valuation Techniques [Table]
Fair Value Measurement Inputs and Valuation Techniques [Table]
Purchase period
Share-Based Compensation Arrangement By Share-based Payment Award, Purchase Period
Share-Based Compensation Arrangement By Share-based Payment Award, Purchase Period
Settlement of capped calls
Adjustments to Additional Paid in Capital, Settlement Of Capped Calls
Adjustments to Additional Paid in Capital, Settlement Of Capped Calls
Total (in shares)
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount
Credit Facility [Domain]
Credit Facility [Domain]
Total payments due
Total
Principal balance of Notes outstanding as of December 31, 2023
Principal balance of Notes outstanding as of September 30, 2024
Long-term and Short-term Debt, Gross
Long-term and Short-term Debt, Gross
Purchase of capped calls
Adjustments to Additional Paid in Capital, Purchase Of Capped Calls
Adjustments to Additional Paid in Capital, Purchase Of Capped Calls
Percentage of the last reported sale price
Debt Instrument, Convertible, Maximum Percentage Of Product Of Last Reported Sale Price And Conversion Rate
Debt Instrument, Convertible, Maximum Percentage Of Product Of Last Reported Sale Price And Conversion Rate
Conversion Period Two
Conversion Period Two [Member]
Conversion Period Two
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Schedule of Shares and Warrants Reserved for Issuance
Schedule of Class of Stock and Warrants or Rights [Table Text Block]
Schedule of Class of Stock and Warrants or Rights
Impact of 100 point increase in discount rate
Sensitivity Analysis of Fair Value, Payable To Securitization Note Holders, Impact of 100 Point Increase In Discount Rate
Sensitivity Analysis of Fair Value, Payable To Securitization Note Holders, Impact of 100 Point Increase In Discount Rate
Goodwill
Goodwill
Changes in accrued interest
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Changes In Accrued Interest
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Changes In Accrued Interest
Taxes paid related to net share settlement of equity awards
Payment, Tax Withholding, Share-Based Payment Arrangement
Authorized share repurchase amount
Share Repurchase Program, Authorized, Amount
Schedule of Borrowings [Line Items]
Schedule of Borrowings [Line Items]
Schedule of Borrowings [Line Items]
Other assets
Other Assets, Miscellaneous
Loans Held For Sale And Investment
Loans Held For Sale And Investment [Member]
Loans Held For Sale And Investment
Options issued and outstanding
Options to purchase common stock
Share-Based Payment Arrangement, Option [Member]
Financing Receivable Portfolio Segment [Axis]
Financing Receivable Portfolio Segment [Axis]
Depreciation
Depreciation
2025
Lessee, Operating Lease, Liability, to be Paid, Year One
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table]
Antidilutive Security, Excluded EPS Calculation [Table]
Loans held-for-investment
Loans Held-For-Investment, Fair Value Disclosure
Loans Held-For-Investment, Fair Value Disclosure
Reclassification of loans
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Reclassification Of Loans
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Reclassification Of Loans
Award Type [Axis]
Award Type [Axis]
Prodigy Software, Inc.
Prodigy Software, Inc. [Member]
Prodigy Software, Inc.
Property, equipment, and software, net
Total property, equipment, and software, net
Property, Plant and Equipment, Net
Total liabilities
Liabilities
Liabilities
Options exercisable, weighted average exercise price per share (in dollars per share)
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price
Convertible Debt
Convertible Debt [Member]
Common stock, par value (in dollars per share)
Common Stock, Par or Stated Value Per Share
Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]
Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table]
Revolving Credit Facility
Revolving Credit Facility [Member]
Expiration Date
Trading Arrangement Expiration Date
Cash flows from investing activities
Net Cash Provided by (Used in) Investing Activities [Abstract]
Other Assets [Abstract]
Total Shareholder Return Amount
Total Shareholder Return Amount
Weighted average coupon yield
Senior Securitized Loans, Weighted Average Coupon Rate
Senior Securitized Loans, Weighted Average Coupon Rate
Consecutive trading days
Debt Instrument, Convertible, Threshold Consecutive Trading Days
Equity Awards Adjustments, Footnote
Equity Awards Adjustments, Footnote [Text Block]
Financial Asset, Period Past Due [Domain]
Financial Asset, Aging [Domain]
Thereafter
Long-term and Short-term Debt, Maturity, After Year Five
Long-term and Short-term Debt, Maturity, After Year Five
Other assets at fair value
Other Assets, Fair Value Disclosure
Customer operations
Customer Operations [Member]
Customer Operations
Total property, equipment, and software
Property, Plant and Equipment, Gross
Issuance of common stock upon exercise of stock options (in shares)
Options exercised (in shares)
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period
Collection agency fees
Collection Agency Fees [Member]
Collection Agency Fees
Debt Instrument [Line Items]
Debt Instrument [Line Items]
Named Executive Officers, Footnote
Named Executive Officers, Footnote [Text Block]
Weighted-Average Exercise Price Per Share
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Other assets (includes $48,897 and $70,676 at fair value as of December 31, 2023 and September 30, 2024, respectively)
Other assets (includes $5,958 and $2,139 at fair value as of December 31, 2023 and September 30, 2024, respectively)
Total other assets
Other Assets
Basis of Presentation
Basis of Accounting, Policy [Policy Text Block]
Weighted-average number of shares outstanding used in computing net loss per share, diluted (in shares)
Weighted-average common shares outstanding used to calculate net loss per share, diluted (in shares)
Weighted Average Number of Shares Outstanding, Diluted
Loans (at fair value)
Loans (at fair value)
Financing receivable, after allowance for credit loss
Fair value
Financing Receivable, after Allowance for Credit Loss
Fair value adjustments and realized losses on beneficial interests, net
Gain (Loss) On Beneficial Interests
Gain (Loss) On Beneficial Interests
MNPI Disclosure Timed for Compensation Value
MNPI Disclosure Timed for Compensation Value [Flag]
Total stockholders’ equity
Beginning balance
Ending balance
Net Assets
Equity, Attributable to Parent
Concentration Risk Type [Domain]
Concentration Risk Type [Domain]
Letter of credit outstanding
Letters of Credit Outstanding, Amount
Schedule of Servicing Liabilities at Fair Value [Table]
Servicing Liability at Fair Value, Activity [Table]
Accounts payable
Accounts Payable
Schedule of Other Assets
Schedule of Other Assets [Table Text Block]
Payments for repurchases of convertible notes
Repurchases of 2026 Notes
Payment for debt repurchased
Repayments of Convertible Debt
Interest rate caps
Interest Rate Cap [Member]
Debt Instrument Conversion [Axis]
Debt Instrument Conversion [Axis]
Debt Instrument Conversion
Consolidated securitization
Consolidated securitization [Member]
Consolidated securitization
Document Fiscal Period Focus
Document Fiscal Period Focus
January 2023 Plan
January 2023 Plan [Member]
January 2023 Plan
All Executive Categories
All Executive Categories [Member]
Convertible debt
Convertible Debt Securities [Member]
2026
Finite-Lived Intangible Asset, Expected Amortization, Year Two
Changed Peer Group, Footnote
Changed Peer Group, Footnote [Text Block]
Options outstanding
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term
Assets
Assets
Assets [Abstract]
Dividend yield
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate
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]
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]
Realized loss on sale of loans, net
Realized Gain (Loss) on Transfer Of Loans, Net
Realized Gain (Loss) on Transfer Of Loans, Net
Document Type
Document Type
Effective interest rate
Debt Instrument, Interest Rate, Effective Percentage
Derivative Contract [Domain]
Derivative Contract [Domain]
Options exercisable
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term
Schedule of Expected Future Amortization Expense
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]
Maximum
Maximum [Member]
Customer B
Customer B [Member]
Customer B
Equity Valuation Assumption Difference, Footnote
Equity Valuation Assumption Difference, Footnote [Text Block]
Total interest income, interest expense, and fair value adjustments, net
Interest Income And Fair Value Adjustment, Net
Interest Income And Fair Value Adjustment, Net
Furniture and fixtures
Furniture and Fixtures [Member]
Net Carrying Value
Finite-Lived Intangible Assets, Net
Antidilutive Securities [Axis]
Antidilutive Securities [Axis]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table]
Schedule of Stock Options Fair Value Assumptions
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
Statistical Measurement [Axis]
Statistical Measurement [Axis]
Non-Rule 10b5-1 Arrangement Terminated
Non-Rule 10b5-1 Arrangement Terminated [Flag]
Non-PEO NEO Average Total Compensation Amount
Non-PEO NEO Average Total Compensation Amount
Beneficial interest assets (at fair value)
Fair value, asset
Fair value of beneficial interest assets
Beneficial Interest Asset
Beneficial Interest Asset
Name
Outstanding Recovery, Individual Name
Disaggregation of Revenue [Line Items]
Disaggregation of Revenue [Line Items]
Variable lease payments
Variable Lease, Cost
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]
Trailing Fee Liabilities
Trailing Fee Liabilities [Member]
Trailing Fee Liabilities
Accrued expenses and other liabilities (includes $10,510 and $18,671 at fair value as of December 31, 2023 and September 30, 2024, respectively)
Accrued expenses and other liabilities
Total accrued expenses and other liabilities
Accrued Liabilities and Other Liabilities
Award Timing Predetermined
Award Timing Predetermined [Flag]
Interest income, interest expense, and fair value adjustments, net:
Revenue Not From Contract With Customer [Abstract]
Revenue Not From Contract With Customer
Customer A
Customer A [Member]
Customer A
Subsequent Event Type [Domain]
Subsequent Event Type [Domain]
Commitment fee threshold
Line of Credit Facility, Unused Capacity, Commitment Fee Threshold, Percentage Of Borrowing Base
Line of Credit Facility, Unused Capacity, Commitment Fee Threshold, Percentage Of Borrowing Base
Redemption price (in percent)
Debt Instrument, Redemption Price, Percentage
Customer relationships
Customer Relationships [Member]
Net loss per share, diluted (in dollars per share)
Earnings Per Share, Diluted
Counterparty Name [Domain]
Counterparty Name [Domain]
Schedule of Assumptions for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Table]
Schedule of Assumptions for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Table]
Restatement does not require Recovery
Restatement Does Not Require Recovery [Text Block]
Schedule Of Beneficial Interest [Line Items]
Schedule Of Beneficial Interest [Line Items]
Schedule Of Beneficial Interest
Platform and referral fees, net
Platform And Referral Fees, Net [Member]
Platform And Referral Fees, Net
Notes receivable and residual certificates (at fair value)
Notes Receivable And Residual Certificates [Member]
Notes Receivable And Residual Certificates
Customer [Axis]
Customer [Axis]
Statement of Financial Position [Abstract]
Fair value adjustments and realized losses on beneficial interests, net
Charge-offs and changes in fair value recorded in earnings
Charge-offs and changes in fair value recorded in earnings
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings
Schedule of Key Terms for Capped Calls
Schedule Of Capped Calls [Table Text Block]
Schedule Of Capped Calls
Sales and marketing
Selling and Marketing Expense
Schedule of Collection Agency and Borrower Fees
Schedule Of Fees And Commissions [Table Text Block]
Schedule Of Fees And Commissions
Beneficial Interests [Abstract]
Beneficial Interests
Gains (losses) recognized
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net
Provision for income taxes
Income Tax Expense (Benefit)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Notional Amount
Derivative, Notional Amount
Trailing fee liabilities
Trailing Fee Liability, Measurement Input
Trailing Fee Liability, Measurement Input
Fair Value
Interest rate caps (at fair value)
Derivative Asset
Options cancelled and forfeited (in shares)
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period
Period of recognition
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition
Revenue from fees, net
Revenue from Contract with Customer, Excluding Assessed Tax
Financing Receivable Portfolio Segment [Domain]
Financing Receivable Portfolio Segment [Domain]
Loans Held-for-Investment
Loans Held For Investment [Member]
Loans Held For Investment
Net cash used in investing activities
Net Cash Provided by (Used in) Investing Activities
10% market-servicing rates increase
Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 10 Percent Increase In Market-Servicing Rates
Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 10 Percent Increase In Market-Servicing Rates
All Adjustments to Compensation
All Adjustments to Compensation [Member]
Customer operations
Customer Operations Expense
Customer Operations Expense
Additional paid-in capital
Additional Paid in Capital
Reorganization expenses
Restructuring Charges
Commitments and Contingencies Disclosure [Abstract]
Impairment of Intangible Assets
Impairment Of Intangible Assets [Member]
Impairment Of Intangible Assets
Restricted cash
Restricted cash
Restricted Cash
Notes receivable and residual certificates
Notes Receivable, Fair Value Disclosure
Long-term Debt, Type [Domain]
Long-Term Debt, Type [Domain]
Entity Address, State or Province
Entity Address, State or Province
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Erroneous Compensation Analysis
Erroneous Compensation Analysis [Text Block]
Beneficial Interests
Beneficial Interest Disclosure [Text Block]
Beneficial Interest Disclosure
Unvested (in dollars per share)
Beginning balance (in dollars per share)
Ending balance (in dollars per share)
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value
Interest cap rate
Derivative, Cap Interest Rate
Liabilities and Stockholders’ Equity
Liabilities and Equity [Abstract]
Restatement Determination Date
Restatement Determination Date
Options vested and expected to vest (in shares)
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number
Reclassification [Table]
Reclassification [Table]
Pay vs Performance Disclosure
Pay vs Performance Disclosure [Table]
Line of Credit Receivable
Line Of Credit Receivable [Member]
Line Of Credit Receivable
Property, Plant and Equipment [Table]
Property, Plant and Equipment [Table]
Options outstanding (in dollars per share)
Options outstanding (in dollars per share)
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price
Operating lease right of use assets
Operating Lease, Right-of-Use Asset
Erroneously Awarded Compensation Recovery
Erroneously Awarded Compensation Recovery [Table]
Beginning balance (in shares)
Ending balance (in shares)
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number
Loans on non-accrual status
Financing Receivable, Threshold Period Past Due
Repayments and other changes in fair value recorded in earnings
Servicing Liability At Fair Value, Repayments And Other Changes At Fair Value, Gain (Loss) Included In Earnings
Servicing Liability At Fair Value, Repayments And Other Changes At Fair Value, Gain (Loss) Included In Earnings
Schedule of Rollforward of Level 3 Liabilities
Fair Value, Liabilities Measured on Recurring Basis [Table Text Block]
Beneficial interests obtained in connection with loan sale
Beneficial Interests Obtained In Connection With Loan Sale
Beneficial Interests Obtained In Connection With Loan Sale
Net gain (loss) on servicing rights and fair value adjustments
Gain (Loss) On Servicing Rights And Fair Value Adjustments
Gain (Loss) On Servicing Rights And Fair Value Adjustments
Net Loss Per Share
Earnings Per Share [Text Block]
Acquisition of beneficial interest assets
Acquisition Of Beneficial Interest Assets
Acquisition Of Beneficial Interest Assets
Issuance of common stock under employee stock purchase plan
Stock Issued During Period, Value, Employee Stock Purchase Plan
Subsequent Event
Subsequent Event [Member]
Schedule of Employee Stock Purchase Plan Fair Value Assumptions
Schedule of Share-Based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]
Issuance of common stock upon exercise of stock options
Stock Issued During Period, Value, Stock Options Exercised
Convertible Debt
Convertible Debt [Table Text Block]
2028
Long-term and Short-term Debt, Maturity, Year Four
Long-term and Short-term Debt, Maturity, Year Four
RSUs granted (in dollars per share)
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value
Peer Group Issuers, Footnote
Peer Group Issuers, Footnote [Text Block]
Restructuring Plan [Axis]
Restructuring Plan [Axis]
Line of credit receivable
Line of credit receivable (at fair value)
Line Of Credit Receivable, Fair Value Disclosure
Line Of Credit Receivable, Fair Value Disclosure
Changes in Presentation within Condensed Consolidated Statements of Cash Flows
Accounting Standards Update and Change in Accounting Principle [Table Text Block]
Beneficial interest liabilities (at fair value)
Beneficial Interest Liability
20% market-servicing rates increase
Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Liabilities, Impact of 20 Percent Increase In Market-Servicing Rates
Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Liabilities, Impact of 20 Percent Increase In Market-Servicing Rates
PEO
PEO [Member]
Name
Trading Arrangement, Individual Name
Restricted cash
Restricted Cash [Member]
Restricted Cash
Long-Lived Tangible Asset [Axis]
Long-Lived Tangible Asset [Axis]
Unused commitment fee
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage
Awards Close in Time to MNPI Disclosures, Table
Awards Close in Time to MNPI Disclosures [Table Text Block]
Schedule of Servicing Liabilities at Fair Value Rollforward
Schedule of Servicing Liabilities at Fair Value [Table Text Block]
Shares reserved of common stock for issuance (in shares)
Common Stock, Capital Shares Reserved for Future Issuance
Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year
Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member]
Payable to securitization note holders
Payables To Securitization Note Holders, Measurement Input
Payables To Securitization Note Holders, Measurement Input
Issuance of line of credit receivable
Issuance Of Line Of Credit Receivable
Issuance Of Line Of Credit Receivable
Aggregate Erroneous Compensation Amount
Aggregate Erroneous Compensation Amount
Local Phone Number
Local Phone Number
Borrowings
Borrowings
Total borrowings
Debt, Long-Term and Short-Term, Combined Amount
Aggregate Erroneous Compensation Not Yet Determined
Aggregate Erroneous Compensation Not Yet Determined [Text Block]
Variable Interest Entity or Potential VIE, Information Unavailability, Disclosures [Abstract]
Variable Interest Entity or Potential VIE, Information Unavailability, Disclosures [Abstract]
Total operating expenses
Operating Expenses
Beneficial interest liabilities
Beneficial Interest Liabilities [Member]
Beneficial Interest Liabilities
Weighted-Average Remaining Contractual Life (years)
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Additional Disclosures [Abstract]
Net changes in operating assets and liabilities:
Increase (Decrease) in Operating Capital [Abstract]
Deposits
Deposits Assets
Upstart Small Dollar Loan Trust
Upstart Small Dollar Loan Trust [Member]
Upstart Small Dollar Loan Trust
PEO Total Compensation Amount
PEO Total Compensation Amount
ESPP purchase price of common stock, percent of market price
Share-Based Compensation Arrangement by Share-Based Payment Award, Purchase Price of Common Stock, Percent
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Warehouse credit facilities
Warehouse Credit Facility [Member]
Warehouse Credit Facility
Long-Lived Tangible Asset [Domain]
Long-Lived Tangible Asset [Domain]
Income Statement Location [Axis]
Statement of Income Location, Balance [Axis]
Options vested and expected to vest, weighted average exercise price per share (in dollars per share)
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price
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
Debt Disclosure [Abstract]
Common Stock
Common Stock [Member]
Forgone Recovery due to Expense of Enforcement, Amount
Forgone Recovery due to Expense of Enforcement, Amount
Schedule of Rollforward of Level 3 Liabilities
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]
Unpaid principal balance of loans
Variable Interest Entity, Primary Beneficiary, Maximum Loss Exposure, Amount
Payments on beneficial interest liabilities
Payments On Beneficial Interest Liabilities
Payments On Beneficial Interest Liabilities
Shares withheld related to net share settlement of restricted stock units (in shares)
Share-Based Payment Arrangement, Shares Withheld for Tax Withholding Obligation
Entity Central Index Key
Entity Central Index Key
General, administrative, and other
General and Administrative Expense [Member]
Trailing fee liability (at fair value)
Trailing Fee Liability At Fair Value, Amount
Trailing Fee Liability At Fair Value, Amount
Non-PEO NEO Average Compensation Actually Paid Amount
Non-PEO NEO Average Compensation Actually Paid Amount
Award Timing, How MNPI Considered
Award Timing, How MNPI Considered [Text Block]
Borrower fees
Borrower Fees [Member]
Borrower Fees
Loan Servicing Liabilities
Loan Servicing Liabilities [Member]
Loan Servicing Liabilities
Changes in fair value recorded in earnings
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings
Stock-based compensation expense
APIC, Share-Based Payment Arrangement, Increase for Cost Recognition
Restricted Stock
Restricted Stock [Member]
Loans
Total assets
Fair value of loans held-for-sale and held-for-investment
Loans Receivable, Fair Value Disclosure
10% adverse change
Sensitivity Analysis of Fair Value, Assets, Impact of 10 Percent Adverse Change in Expected Prepayment Rates
Sensitivity Analysis of Fair Value, Assets, Impact of 10 Percent Adverse Change in Expected Prepayment Rates
Title
Trading Arrangement, Individual Title
Additions
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Additions
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Additions
Consolidated Entities [Axis]
Consolidated Entities [Axis]
Payable to securitization note holders (at fair value)
Payable to securitization note holders
Payable To Securitization Note Holders, At Fair Value
Payable To Securitization Note Holders, At Fair Value
Change in fair value of other financial instruments
Increase (Decrease) in Other Financial Instruments Used in Operating Activities
Variable Interest Entities and Consolidated Securitization
Consolidation, Variable Interest Entity, Policy [Policy Text Block]
City Area Code
City Area Code
Unfunded Loan Commitment
Unfunded Loan Commitment [Member]
Unrealized loss on loans, loan charge-offs, and other fair value adjustments, net
Unrealized Gain (Loss), Charge-Offs, And Other Fair Value Adjustments, Net
Unrealized Gain (Loss), Charge-Offs, And Other Fair Value Adjustments, Net
Insider Trading Policies and Procedures Not Adopted
Insider Trading Policies and Procedures Not Adopted [Text Block]
Schedule of Components of Interest Income and Fair Value Adjustments, Net
Interest Income and Interest Expense Disclosure [Table Text Block]
Schedule of Significant Unobservable Inputs
Fair Value Measurement Inputs and Valuation Techniques [Table Text Block]
Weighted-Average Grant Date Fair Value Per Share
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Subsequent Event Type [Axis]
Subsequent Event Type [Axis]
Earnings Per Share [Abstract]
Accumulated deficit
Retained Earnings (Accumulated Deficit)
Proceeds from beneficial interest assets
Proceeds From Beneficial Interest Assets
Proceeds From Beneficial Interest Assets
Repurchase and retirement of common stock (in shares)
Stock Repurchased and Retired During Period, Shares
Class of Stock [Domain]
Class of Stock [Domain]
Options cancelled and forfeited (in dollars per share)
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price
Loans Held in Consolidated Securitization
Loans Held in Consolidated Securitization [Member]
Loans Held in Consolidated Securitization
Gross debt issuance cost
Debt Issuance Costs, Gross
Schedule of Aggregate Principal Outstanding of All Debt
Schedule of Debt [Table Text Block]
General, administrative, and other
General and Administrative Expense
Aggregate Available
Trading Arrangement, Securities Aggregate Available Amount
Equity Awards Adjustments
Equity Awards Adjustments [Member]
Operating lease liabilities
Operating lease liabilities
Operating Lease, Liability
Underlying Securities
Award Underlying Securities Amount
PRSUs outstanding
Performance Shares [Member]
Amendment Flag
Amendment Flag
Stock Appreciation Rights (SARs)
Stock Appreciation Rights (SARs) [Member]
Aggregate Intrinsic Value
Share Based Compensation Arrangement By Share Based Payment Award Options Aggregate Intrinsic Value [Abstract]
Share Based Compensation Arrangement By Share Based Payment Award Options Aggregate Intrinsic Value
Credit risk rate
Measurement Input, Entity Credit Risk [Member]
Servicing Assets at Fair Value [Line Items]
Servicing Assets at Fair Value [Line Items]
Subsequent Events [Abstract]
Borrowings
Debt Disclosure [Text Block]
Fair Value Hierarchy and NAV [Domain]
Fair Value Hierarchy and NAV [Domain]
Recovery of Erroneously Awarded Compensation Disclosure [Line Items]
Aggregate principal amount
Debt Instrument, Face Amount
Auto Loans
Auto Loans [Member]
Auto Loans
Repayments and settlements
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements
Entity Address, Postal Zip Code
Entity Address, Postal Zip Code
Beneficial interests
Beneficial Interests, Net [Member]
Beneficial Interests, Net
Transfer of loans to consolidated securitization
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Transfer Of Loans To Consolidated Securitization
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Transfer of Loans to Consolidated securitization
Net loss before income taxes
Income (Loss) Attributable to Parent, before Tax
Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested
Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member]
Trading days
Debt Instrument, Convertible, Threshold Trading Days
RSUs cancelled and forfeited (in dollars per share)
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value
Trailing fee liabilities
Trailing Fee Liabilities, Fair Value Disclosure
Trailing Fee Liabilities, Fair Value Disclosure
Thereafter
Finite-Lived Intangible Asset, Expected Amortization, after Year Four
Finite-Lived Intangible Asset, Expected Amortization, after Year Four
Gain on debt extinguishment
Gain on debt extinguishment
Gain (Loss) on Extinguishment of Debt
Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested
Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member]
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity, Not Primary Beneficiary [Member]
Number of Options
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding [Roll Forward]
Accrued expenses
Accrued Liabilities
Other consolidated VIEs
Other Variable Interest Entities [Member]
Other Variable Interest Entities
Shares available for issuance under employee stock purchase plan
Purchase rights committed under the ESPP
Employee Stock [Member]
Reorganizations [Abstract]
Adjustment To PEO Compensation, Footnote
Adjustment To PEO Compensation, Footnote [Text Block]
Class of Financing Receivable [Axis]
Class of Financing Receivable [Axis]
Amortization expense
Amortization
Change in fair value of loans
Increase (Decrease) in Finance Receivables
Compensation Actually Paid vs. Other Measure
Compensation Actually Paid vs. Other Measure [Text Block]
Purchases and originations of loans held-for-investment
Payment for Acquisition, Loan, Held-for-Investment
Change in fair value of servicing assets
Increase (Decrease) In Fair Value Of Servicing Assets
Increase (Decrease) In Fair Value Of Servicing Assets
Schedule of Stock by Class [Table]
Stock, Class of Stock [Table]
Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year
Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member]
Total assets
Assets
Assets
Schedule of Servicing Assets at Fair Value Rollforward
Schedule of Servicing Assets at Fair Value [Table Text Block]
Credit risk rate
Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Expected Credit Losses
Purchases of property and equipment
Payments to Acquire Property, Plant, and Equipment
Obligation to Repurchase Loans
Obligation to Repurchase Receivables Sold [Member]
Forgone Recovery due to Violation of Home Country Law, Amount
Forgone Recovery due to Violation of Home Country Law, Amount
Prepayment rate
Measurement Input, Prepayment Rate [Member]
Schedule of Effective Tax Rates
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]
Termination Date
Trading Arrangement Termination Date
2026
Lessee, Operating Lease, Liability, to be Paid, Year Two
Other liabilities
Other Liabilities
Debt Instrument [Axis]
Debt Instrument [Axis]
Payable to investors for beneficial interest assets
Increase (Decrease) In Payable To Investors For Beneficial Interest Assets
Increase (Decrease) In Payable To Investors For Beneficial Interest Assets
Discount rate
Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Discount Rate
Net loss
Net loss
Net loss
Net loss
Net Income (Loss) Attributable to Parent
Trading Arrangement:
Trading Arrangement [Axis]
Schedule of Assets and Liabilities Measured at Fair Value
Fair Value, by Balance Sheet Grouping [Table Text Block]
Pay vs Performance Disclosure, Table
Pay vs Performance [Table Text Block]
Equity Awards Adjustments, Excluding Value Reported in Compensation Table
Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member]
Purchase of capped calls
Purchase of capped calls
Payments For Capped Calls
Payments For Capped Calls
2029
Long-term and Short-term Debt, Maturity, Year Five
Long-term and Short-term Debt, Maturity, Year Five
Entity File Number
Entity File Number
Consolidated Entities [Domain]
Consolidated Entities [Domain]
Income Statement [Abstract]
Entity Address, Address Line One
Entity Address, Address Line One
Denominator:
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Entity Address, Address Line Two
Entity Address, Address Line Two
Restructuring Plan [Domain]
Restructuring Plan [Domain]
Accrued expenses and other liabilities
Increase (Decrease) in Accrued Liabilities and Other Operating Liabilities
Name
Forgone Recovery, Individual Name
Options exercisable
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Intrinsic Value
Weighted-average remaining lease term (in years)
Operating Lease, Weighted Average Remaining Lease Term
Principal payments made on securitization notes
Repayments of Accounts Receivable Securitization
Loss Contingency, Nature [Domain]
Loss Contingency, Nature [Domain]
Number of VIEs whom exercised clean up calls
Variable Interest Entity, Qualitative or Quantitative Information, Number Of Variable Interest Entity
Variable Interest Entity, Qualitative or Quantitative Information, Number Of Variable Interest Entity
Other
Other Noncash Income (Expense)
Award Timing MNPI Considered
Award Timing MNPI Considered [Flag]
Line of Credit Facility [Line Items]
Line of Credit Facility [Line Items]
One-time non-cash savings amount
Restructuring And Related Cost, One-Time Non-Cash Savings Amount
Restructuring And Related Cost, One-Time Non-Cash Savings Amount
Outstanding Aggregate Erroneous Compensation Amount
Outstanding Aggregate Erroneous Compensation Amount
Issuances
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Issuances
PEO Actually Paid Compensation Amount
PEO Actually Paid Compensation Amount
Adjustment to Compensation:
Adjustment to Compensation [Axis]
Accounts Receivable
Accounts Receivable [Member]
Maximum Exposure to Losses
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount
Document Quarterly Report
Document Quarterly Report
Interest expense
Interest Expense, Operating
Purchases and originations of loans
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases
Pension Adjustments Service Cost
Pension Adjustments Service Cost [Member]
Initial Strike Price per Share, Subject to Certain Adjustments (in dollars per share)
Debt Instrument, Convertible, Capped Calls Initial Strike Price
Debt Instrument, Convertible, Capped Calls Initial Strike Price
Principal payments received for loans held-for-sale
Proceeds from Collection, Loan, Held-for-Sale
Weighted-average number of shares outstanding used in computing net loss per share, basic (in shares)
Weighted-average common shares outstanding used to calculate net loss per share, basic (in shares)
Weighted Average Number of Shares Outstanding, Basic
Stock Price or TSR Estimation Method
Stock Price or TSR Estimation Method [Text Block]
Capitalized internally developed software balances, net of accumulated amortization
Capitalized Computer Software, Net
Amortization of debt issuance costs
Amortization of Debt Issuance Costs and Discounts
Name
Awards Close in Time to MNPI Disclosures, Individual Name
Debt Activity [Roll Forward]
Convertible Debt Activity [Roll Forward]
Convertible Debt Activity
Revenue Benchmark
Revenue Benchmark [Member]
Entity Filer Category
Entity Filer Category
Loss Contingencies [Line Items]
Loss Contingencies [Line Items]
2026
Long-term and Short-term Debt, Maturity, Year Two
Long-term and Short-term Debt, Maturity, Year Two
Proceeds from warehouse borrowings
Proceeds from Long-Term Lines of Credit
Statistical Measurement [Domain]
Statistical Measurement [Domain]
Customer D
Customer D [Member]
Customer D
Schedule of Operating Lease Expense and Supplemental Cash and Non-cash Information
Lease, Cost [Table Text Block]
Schedule of Aggregate Fair Value and Principal Outstanding of All Loans And Loans 90 Days or More Past Due
Financing Receivable, Past Due [Table Text Block]
Schedule of Level 3 Fair Value Assumptions for Loan Servicing Assets and Liabilities
Schedule of Assumptions for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Table Text Block]
Principal payments received for loans held-for-investment
Proceeds from Principal Repayment, Loan and Lease, Held-for-Investment
All Trading Arrangements
All Trading Arrangements [Member]
Compensation Actually Paid vs. Net Income
Compensation Actually Paid vs. Net Income [Text Block]
Schedule of Net Loss Per Share
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]
Award vesting period
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period
Consolidated warehouse entities
Consolidated Warehouse Entities [Member]
Consolidated Warehouse Entities
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity, Primary Beneficiary [Member]
Subscription fee
Subscription Fee [Member]
Subscription Fee
Rule 10b5-1 Arrangement Adopted
Rule 10b5-1 Arrangement Adopted [Flag]
Annual target bonus opportunity percentage
Annual Target Bonus Opportunity, Percentage Of Salary, Percent
Annual Target Bonus Opportunity, Percentage Of Salary, Percent
Awards Close in Time to MNPI Disclosures
Awards Close in Time to MNPI Disclosures [Table]
Derivative [Line Items]
Derivative [Line Items]
Cash (received) paid for income taxes, net
Income Taxes Paid, Net
Common stock
Common Class A [Member]
Initial conversion rate (in shares)
Debt Instrument, Convertible, Conversion Ratio
Pay vs Performance Disclosure [Line Items]
Peer Group Total Shareholder Return Amount
Peer Group Total Shareholder Return Amount
Derivative [Table]
Derivative [Table]
Schedule of Beneficial Interests
Schedule Of Beneficial Interests [Table Text Block]
Schedule Of Beneficial Interests
Sale of loans
Servicing Liability at Fair Value, Additions
Other Performance Measure, Amount
Other Performance Measure, Amount
2027
Finite-Lived Intangible Asset, Expected Amortization, Year Three
Leases
Lessee, Operating Leases [Text Block]
Common stock, outstanding (in shares)
Beginning balance (in shares)
Ending balance (in shares)
Common Stock, Shares, Outstanding
Rent expense
Operating Lease, Cost
Upstart Auto Warehouse Trust
UAWT Warehouse Credit Facility [Member]
UAWT Warehouse Credit Facility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Entity Tax Identification Number
Entity Tax Identification Number
Percentage of workforce reduction
Restructuring and Related Cost, Number of Positions Eliminated, Inception to Date Percent
Schedule of Finite-Lived Intangible Assets [Table]
Intangible Asset, Finite-Lived [Table]
Other changes
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Other Increase (Decrease)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Other Increase (Decrease)
2026 Notes
2026 ("Notes")
Twenty Twenty Six Notes [Member]
Twenty Twenty Six Notes
Plan Name [Axis]
Plan Name [Axis]
Equity Components [Axis]
Equity Components [Axis]
Immediate resale of loans
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Immediate Resale to Investors
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Immediate Resale to Investors
Loan servicing assets
Fair value of loan servicing assets
Fair value, beginning balance
Fair value, ending balance
Loan servicing assets (at fair value)
Servicing Asset at Fair Value, Amount
Capitalized cost amortization term
Capitalized Contract Cost, Amortization Period
Fair value, beginning balance
Fair value, ending balance
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value
Capitalized stock-based compensation expense
Share-Based Payment Arrangement, Amount Capitalized
Internally developed software impairment
Capitalized Computer Software, Impairments
Business Acquisition, Acquiree [Domain]
Business Acquisition, Acquiree [Domain]
Receivable [Domain]
Receivable [Domain]
Balances aggregate intrinsic value
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value
Supplemental disclosures of non-cash investing and financing activities
Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]
Developed technology
Developed Technology Rights [Member]
Shares available for future issuance under 2020 plan
2020 Equity Incentive Plan [Member]
2020 Equity Incentive Plan
Weighted Average
Weighted Average [Member]
Sales and marketing
Selling and Marketing Expense [Member]
Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table
Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member]
Issuance of common stock under employee stock purchase plan (in shares)
Stock Issued During Period, Shares, Employee Stock Purchase Plans
Asset Pledged as Collateral
Asset Pledged as Collateral [Member]
Total cash and restricted cash
Cash and restricted cash at beginning of period
Cash and restricted cash at end of period
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents
Fair Value Measurement
Fair Value of Financial Instruments, Policy [Policy Text Block]
Loan servicing liabilities
Fair value of loan servicing liabilities
Fair value, beginning balance
Fair value, ending balance
Loan servicing liabilities (at fair value)
Servicing Liability at Fair Value, Amount
Loans (at fair value)
Loans Receivable [Member]
Servicing and other fees, net
Servicing Fees, Net [Member]
Servicing Fees, Net
Forgone Recovery due to Disqualification of Tax Benefits, Amount
Forgone Recovery due to Disqualification of Tax Benefits, Amount
Issuance costs of new convertible notes
Debt Issuance Costs Incurred During Noncash or Partial Noncash Transaction
Product and Service [Domain]
Product and Service [Domain]
RSUs vested (in dollars per share)
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value
Fair Value Disclosures [Abstract]
Expected credit loss rates on underlying loans
Expected Credit Loss Rate [Abstract]
Expected Credit Loss Rate
Security Exchange Name
Security Exchange Name
Basis spread on variable rate
Debt Instrument, Basis Spread on Variable Rate
Non-cash interest expense
Paid-in-Kind Interest
Options exercised (in dollars per share)
Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price
Engineering and product development
Engineering And Product Development [Member]
Engineering And Product Development
Number of Shares
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Forgone Recovery, Explanation of Impracticability
Forgone Recovery, Explanation of Impracticability [Text Block]
Engineering and product development
Research and Development Expense
Loans held in consolidated securitization
Securitized Loans, Measurement Input
Securitized Loans, Measurement Input
Sale of loans
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales
Goodwill and Intangible Assets Disclosure [Abstract]
Number of shares available for settlement of cancelled awards (in shares)
Share-Based Compensation Arrangement, Awards Cancelled, Settlement In Shares
Share-Based Compensation Arrangement, Awards Cancelled, Settlement In Shares
Common stock, issued (in shares)
Common Stock, Shares, Issued
Other
Other Assets [Member]
10% adverse change
Sensitivity Analysis of Fair Value, Liabilities, Impact of 10 Percent Adverse Change in Expected Credit Loss Rates
Sensitivity Analysis of Fair Value, Liabilities, Impact of 10 Percent Adverse Change in Expected Credit Loss Rates
Maximum borrowing capacity
Line of Credit Facility, Maximum Borrowing Capacity
Concentration risk (in percent)
Concentration Risk, Percentage
Outstanding principal balance
Financing Receivable, before Allowance for Credit Loss
Computer and networking equipment
Computer Equipment [Member]
Insider Trading Policies and Procedures Adopted
Insider Trading Policies and Procedures Adopted [Flag]
Accumulated depreciation and amortization
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment
Cash
Cash
Cash
Cash
20% adverse change
Sensitivity Analysis of Fair Value, Assets, Impact of 20 Percent Adverse Change in Expected Prepayment Rates
Sensitivity Analysis of Fair Value, Assets, Impact of 20 Percent Adverse Change in Expected Prepayment Rates
Common stock, authorized (in shares)
Common Stock, Shares Authorized
Subscription agreements term
Subscription Agreements Term
Subscription Agreements Term
Schedule Of Beneficial Interest [Table]
Schedule Of Beneficial Interest [Table]
Schedule Of Beneficial Interest
Remaining 2024
Finite-Lived Intangible Asset, Expected Amortization, Remainder of Fiscal Year
Long-term Debt, Type [Axis]
Long-Term Debt, Type [Axis]
Servicing Liability at Fair Value, Amount [Roll Forward]
Servicing Liability at Fair Value, Amount [Roll Forward]
Initial conversion price (in dollars per share)
Debt Instrument, Convertible, Conversion Price
Options granted (in shares)
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net Carrying Amount
Long-Term Debt
Pension Adjustments Prior Service Cost
Pension Adjustments Prior Service Cost [Member]
Purchases of loans held-for-sale
Payment for Purchase, Loan, Held-for-Sale
Assumption for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Line Items]
Assumption for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Line Items]
Issuance of common stock upon settlement of restricted stock units
Stock Issued During Period, Value, Restricted Stock Award, Gross
Pension Benefits Adjustments, Footnote
Pension Benefits Adjustments, Footnote [Text Block]
Total Shareholder Return Vs Peer Group
Total Shareholder Return Vs Peer Group [Text Block]
Restricted stock issued (in shares)
Stock Issued During Period, Shares, Restricted Stock Award, Gross
RSUs vested (in shares)
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period
20% adverse change
Sensitivity Analysis of Fair Value, Liabilities, Impact of 20 Percent Adverse Change in Expected Credit Loss Rates
Sensitivity Analysis of Fair Value, Liabilities, Impact of 20 Percent Adverse Change in Expected Credit Loss Rates
Risk-free interest rate
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate
Accounting Policies [Abstract]
Liabilities:
Liabilities
Liabilities [Abstract]
Discount rates
Discount Rate [Abstract]
Discount Rate
Revenue:
Revenues [Abstract]
Unamortized debt discount
Debt Instrument, Unamortized Discount
Leasehold improvements
Leasehold Improvements [Member]
Current Fiscal Year End Date
Current Fiscal Year End Date
Less: Present value adjustment
Lessee, Operating Lease, Liability, Undiscounted Excess Amount
Sukhinder Singh Cassidy [Member]
Sukhinder Singh Cassidy
Loans receivable
Loans Receivable, Measurement Input
Loans Receivable, Measurement Input
PEO Name
PEO Name
Beneficial interest liabilities
Beneficial Interest, Liability, Measurement Input
Beneficial Interest, Liability, Measurement Input
Award Type [Domain]
Award Type [Domain]
Remaining 2024
Long-term and Short-term Debt, Maturity, Remainder Of Fiscal Year
Long-term and Short-term Debt, Maturity, Remainder Of Fiscal Year
Compensation Actually Paid vs. Company Selected Measure
Compensation Actually Paid vs. Company Selected Measure [Text Block]
Revision of Prior Period [Axis]
Revision of Prior Period [Axis]
Non-PEO NEO
Non-PEO NEO [Member]
Beneficial interest assets
Beneficial Interest, Asset, Measurement Input
Beneficial Interest, Asset, Measurement Input
Impact of 200 point increase in discount rate
Sensitivity Analysis of Fair Value, Payable To Securitization Note Holders, Impact of 200 Point Increase In Discount Rate
Sensitivity Analysis of Fair Value, Payable To Securitization Note Holders, Impact of 200 Point Increase In Discount Rate
Additional Paid-in Capital
Additional Paid-in Capital [Member]
Settlement of capped calls
Proceeds From Settlement Of Capped Calls
Proceeds From Settlement Of Capped Calls
Class of Stock [Line Items]
Class of Stock [Line Items]
Conversion Period One
Conversion Period One [Member]
Conversion Period One
Accrued interest income
Financing Receivable, Accrued Interest, after Allowance for Credit Loss
Recently Adopted Accounting Pronouncements and Recently Issued Accounting Pronouncements
New Accounting Pronouncements, Policy [Policy Text Block]
Class of Stock [Axis]
Class of Stock [Axis]
20% market-servicing rates increase
Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 20 Percent Increase In Market-Servicing Rates
Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 20 Percent Increase In Market-Servicing Rates
Finite-Lived Intangible Assets by Major Class [Axis]
Finite-Lived Intangible Assets by Major Class [Axis]
Accumulated Amortization
Finite-Lived Intangible Assets, Accumulated Amortization
Change in fair value of beneficial interest assets
Increase (Decrease) In Fair Value Of Beneficial Interest Assets
Increase (Decrease) In Fair Value Of Beneficial Interest Assets
Name
Measure Name
Entity Interactive Data Current
Entity Interactive Data Current
Type of Restructuring [Domain]
Type of Restructuring [Domain]
Securities retained under consolidated securitization transaction
Securities Retained Under Consolidated Securitization Transaction
Securities Retained Under Consolidated Securitization Transaction
Schedule of Borrowings [Table]
Schedule of Borrowings [Table]
Schedule of Borrowings [Table]
Disaggregation of Revenue [Table]
Disaggregation of Revenue [Table]
Employee Severance
Employee Severance [Member]
Reorganization Expenses
Restructuring and Related Activities Disclosure [Text Block]
Schedule of Customers Accounting for Greater Than 10% of Total Revenue
Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block]
Stock-based compensation
Share-Based Payment Arrangement, Noncash Expense
Stated interest rate
Debt Instrument, Interest Rate, Stated Percentage
Customer C
Customer C [Member]
Customer C
Supplemental disclosures of cash flow information
Supplemental Cash Flow Information [Abstract]
Fair value, liability
Beneficial interest liabilities
Beneficial Interest Liabilities
Beneficial Interest Liabilities
Revenue from fees, net
Revenue From Fees, Net
Revenue From Fees, Net
Concentration Risk Benchmark [Domain]
Concentration Risk Benchmark [Domain]
Effective tax rate
Effective Income Tax Rate Reconciliation, Percent
Loss from operations
Operating Income (Loss)
Total liabilities and stockholders’ equity
Liabilities and Equity
Subsequent Events
Subsequent Events [Text Block]
Rule 10b5-1 Arrangement Terminated
Rule 10b5-1 Arrangement Terminated [Flag]
Fair Value Hierarchy and NAV [Axis]
Fair Value Hierarchy and NAV [Axis]
Schedule of Fair Value by Classes of Loans Held by the Company
Fair Value, Assets Measured on Recurring and Nonrecurring Basis [Table Text Block]
Derivative Financial Instruments
Derivative Instruments and Hedging Activities Disclosure [Text Block]
Finite-Lived Intangible Assets, Major Class Name [Domain]
Finite-Lived Intangible Assets, Major Class Name [Domain]
Schedule of Restricted Stock Units and Restricted Stock
Share-Based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]
Schedule of Maturities of All Borrowings
Schedule of Maturities of Long-Term Debt [Table Text Block]
Underlying Security Market Price Change
Underlying Security Market Price Change, Percent
Measurement Input Type [Axis]
Measurement Input Type [Axis]
Individual:
Individual [Axis]
Other fees
Other Fees [Member]
Other Fees
Shares withheld related to net share settlement of restricted stock units
Share-Based Payment Arrangement, Decrease for Tax Withholding Obligation
Expected term (in years)
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term
Product and Service [Axis]
Product and Service [Axis]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment [Line Items]
Statement [Line Items]
Statement [Line Items]
Measurement Input Type [Domain]
Measurement Input Type [Domain]
100 basis point increase
Sensitivity Analysis of Fair Value, Assets, Impact of 100 Basis Point Increase In Discount Rates
Sensitivity Analysis of Fair Value, Assets, Impact of 100 Basis Point Increase In Discount Rates
Loss contingency, ownership loan facilitated term
Loss Contingency, Ownership Loan Facilitated Term
Loss Contingency, Ownership Loan Facilitated Term
Operating expenses:
Operating Expenses [Abstract]
Schedule of Property, Equipment, and Software
Property, Plant and Equipment [Table Text Block]
Compensation Actually Paid vs. Total Shareholder Return
Compensation Actually Paid vs. Total Shareholder Return [Text Block]
Sublease income
Sublease Income
10% market-servicing rates increase
Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Liabilities, Impact of 10 Percent Increase In Market-Servicing Rates
Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Liabilities, Impact of 10 Percent Increase In Market-Servicing Rates
Fair value, beginning balance
Fair value, ending balance
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value
Internally developed software
Software Development [Member]
Maximum estimate of potential loss
Loss Contingency, Estimate of Possible Loss
Loans held-for-sale
Loan, Held-for-Sale, Fair Value Disclosure
Schedule of Rollforward of Level 3 Assets
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]
Minimum
Minimum [Member]
Net fair value and accrued interest adjustments
Financing Receivable, Allowance for Credit Loss
Adoption Date
Trading Arrangement Adoption Date
Notes receivable and residual certificates (at fair value)
Other Receivables
Beneficial Interests
Beneficial Interests [Member]
Beneficial Interests
Variable Interest Entity [Line Items]
Variable Interest Entity [Line Items]
Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year
Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member]
Derivative Instrument [Axis]
Derivative Instrument [Axis]
Schedule of Sensitivity Analysis of Fair Value
Schedule of Sensitivity Analysis of Fair Value [Table Text Block]
Schedule of Sensitivity Analysis of Fair Value
Principal Amount
Long-Term Debt, Gross
HELOCs
Home Equity Line of Credit [Member]
Exercise Price
Award Exercise Price
2027
Long-term and Short-term Debt, Maturity, Year Three
Long-term and Short-term Debt, Maturity, Year Three
Schedule of Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets [Table]
Schedule of Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets [Table]
Arrangement Duration
Trading Arrangement Duration
Goodwill and Intangible assets
Goodwill and Intangible Assets Disclosure [Text Block]
Schedule of Variable Interest Entities [Table]
Variable Interest Entity [Table]
Stockholders’ equity:
Equity, Attributable to Parent [Abstract]
Fair value and other adjustments
Total fair value and other adjustments, net
Fair Value And Other Adjustments, Net
Fair Value And Other Adjustments, Net
Material Terms of Trading Arrangement
Material Terms of Trading Arrangement [Text Block]
2028
Finite-Lived Intangible Asset, Expected Amortization, Year Four
All Individuals
All Individuals [Member]
Description of Business and Significant Accounting Policies
Basis of Presentation and Significant Accounting Policies [Text Block]
Repayments received
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Repayments Received
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Repayments Received
Income Tax Disclosure [Abstract]
Fair Value
Debt Instrument, Fair Value Disclosure
Other income, net
Other Nonoperating Income (Expense)
Intangible assets, net
Intangible Assets, Net (Excluding Goodwill)
Statement of Stockholders' Equity [Abstract]
Schedule of Fair Value Sensitivity of Loan Servicing Assets and Liabilities to Adverse Changes in Key Assumptions
Schedule of Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets [Table Text Block]
Unrecognized stock-based compensation expense
Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount
Cash and Restricted Cash
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations [Abstract]
Assets
Assets, Fair Value Disclosure [Abstract]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table]
Settlement of borrowings in connection with loan sale
Notes Reduction
Restructuring Cost and Reserve [Line Items]
Restructuring Cost and Reserve [Line Items]
Shares of Common Stock Covered, Subject to Anti-Dilution Adjustments (in shares)
Debt Instrument, Convertible, Capped Calls Number Of Shares Of Common Stock Covered
Debt Instrument, Convertible, Capped Calls Number Of Shares Of Common Stock Covered
Liability Class [Axis]
Liability Class [Axis]
Payable to Securitization Note Holders
Payables to Securitization Note Holders [Member]
Payables to Securitization Note Holders
Risk free rate, maximum
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum
Expected volatility
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate
Valuation Approach and Technique [Axis]
Valuation Approach and Technique [Axis]
Other assets
Increase (Decrease) in Other Operating Assets
Kerry Whorton Cooper [Member]
Kerry Whorton Cooper
Schedule of Accrued Expenses and Other Liabilities
Schedule of Accrued Liabilities [Table Text Block]
Commitments and Contingencies
Commitments and Contingencies Disclosure [Text Block]
Purchase of loans for immediate resale
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchase Of Loans For Immediate Resale To Investors
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchase Of Loans For Immediate Resale To Investors
Measure:
Measure [Axis]
Asset Class [Domain]
Asset Class [Domain]
Entity Emerging Growth Company
Entity Emerging Growth Company
Additional repurchased amount
Debt Instrument, Additional Repurchased Face Amount
Debt Instrument, Additional Repurchased Face Amount
Total liabilities
Liabilities, Fair Value Disclosure
Non-GAAP Measure Description
Non-GAAP Measure Description [Text Block]
Expected volatility, minimum
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum
Equity Component [Domain]
Equity Component [Domain]
Loans held in consolidated securitization
Loans Held in Consolidated Securitization, Fair Value Disclosure
Loans Held in Consolidated Securitization, Fair Value Disclosure
Additional 402(v) Disclosure
Additional 402(v) Disclosure [Text Block]
Entity Shell Company
Entity Shell Company
Entity Incorporation, State or Country Code
Entity Incorporation, State or Country Code
Contract costs capitalized
Capitalized Contract Cost, Net
Repurchase amount
Debt Instrument, Repurchased Face Amount
Statement [Table]
Statement [Table]
Interest expense
Interest Expense, Debt
Counterparty Name [Axis]
Counterparty Name [Axis]
Schedule of Financial Assets and Liabilities from Variable Interest Entities
Schedule of Variable Interest Entities [Table Text Block]
Numerator:
Net Income (Loss) Available to Common Stockholders, Diluted [Abstract]
Schedule of the Notional Amount as well as the Fair Value of Interest Rate Caps
Derivatives Not Designated as Hedging Instruments [Table Text Block]
Repayments and settlements / Payments on beneficial interests
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements
Debt Instrument Conversion [Domain]
Debt Instrument Conversion [Domain]
Debt Instrument Conversion [Domain]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due [Line Items]
Cash paid for interest
Interest Paid, Excluding Capitalized Interest, Operating Activities
Concentration Risk Benchmark [Axis]
Concentration Risk Benchmark [Axis]
ULT Warehouse Credit Facility - UnCommitted
ULT Warehouse Credit Facility - UnCommitted [Member]
ULT Warehouse Credit Facility - UnCommitted
Statement of Cash Flows [Abstract]
Revision of Prior Period [Domain]
Revision of Prior Period [Domain]
Options exercisable (in shares)
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Number
Schedule of Long-Term Debt Instruments [Table]
Schedule of Long-Term Debt Instruments [Table]
Upstart Loan Trust
ULT Warehouse Credit Facility [Member]
ULT Warehouse Credit Facility
Weighted average grant date fair value (in dollars per share)
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value
Non-marketable equity securities
Equity Securities without Readily Determinable Fair Value, Amount
Income Taxes
Income Tax Disclosure [Text Block]
2028
Lessee, Operating Lease, Liability, to be Paid, Year Four
Unpaid principal balance, asset
Beneficial Interest, Asset, Unpaid Principal Balance
Beneficial Interest, Asset, Unpaid Principal Balance
Valuation Technique, Discounted Cash Flow
Valuation Technique, Discounted Cash Flow [Member]
Repayments of warehouse borrowings
Repayment of warehouse borrowings
Repayments of Long-Term Lines of Credit
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Weighted-average discount rate
Operating Lease, Weighted Average Discount Rate, Percent
Net cash provided by financing activities
Net Cash Provided by (Used in) Financing Activities
Credit Facility [Axis]
Credit Facility [Axis]
Loss Contingency Nature [Axis]
Loss Contingency Nature [Axis]
20% adverse change
Sensitivity Analysis of Fair Value, Assets, Impact of 20 Percent Adverse Change in Expected Credit Loss Rates
Sensitivity Analysis of Fair Value, Assets, Impact of 20 Percent Adverse Change in Expected Credit Loss Rates
Payable to investors
Payable To Investors
Payable To Investors
Entity Registrant Name
Entity Registrant Name
Adjustment to Non-PEO NEO Compensation Footnote
Adjustment to Non-PEO NEO Compensation Footnote [Text Block]
Depreciation and amortization
Depreciation, Depletion and Amortization
Dave Girouard [Member]
Dave Girouard
Fair Value as of Grant Date
Award Grant Date Fair Value
Customer Concentration Risk
Customer Concentration Risk [Member]
Options vested and expected to vest
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value
Fair Value, Inputs, Level 2
Fair Value, Inputs, Level 2 [Member]
Schedule of Disaggregation of Revenue by Type of Service
Disaggregation of Revenue [Table Text Block]
Upstart Auto Warehouse Trust 2
UAWT Warehouse Credit Facility II [Member]
UAWT Warehouse Credit Facility II
Market-servicing rate
Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Market Servicing Rate
Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Market Servicing Rate
Schedule of Stock-based Compensation Expense
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]
Consolidated VIEs
Consolidation, Policy [Policy Text Block]
Schedule of Restructuring and Related Costs [Table]
Restructuring Cost [Table]
Restatement Determination Date:
Restatement Determination Date [Axis]
Title of 12(b) Security
Title of 12(b) Security
Concentration Risk Type [Axis]
Concentration Risk Type [Axis]
Common stock, $0.0001 par value; 700,000,000 shares authorized; 86,330,303 and 90,998,255 shares issued and outstanding as of December 31, 2023 and September 30, 2024, respectively
Common Stock, Value, Issued
Share-Based Payment Arrangement [Abstract]
Aggregate capital under risk-sharing arrangements
Beneficial Interests, Maximum Loss Exposure
Beneficial Interests, Maximum Loss Exposure
Thereafter
Lessee, Operating Lease, Liability, to be Paid, after Year Four
Lessee, Operating Lease, Liability, to be Paid, after Year Four
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets [Line Items]
Fair Value by Liability Class [Domain]
Fair Value by Liability Class [Domain]
Cash flows from financing activities
Net Cash Provided by (Used in) Financing Activities [Abstract]
Valuation Approach and Technique [Domain]
Valuation Approach and Technique [Domain]
Net loss per share, basic (in dollars per share)
Earnings Per Share, Basic
Loan Servicing Assets
Loan Servicing Assets [Member]
Loan Servicing Assets
Notes receivable and residual certificates
Notes Receivable, Measurement Input
Notes Receivable, Measurement Input
Cash paid for amounts included in the measurement of lease liabilities
Operating Lease, Payments
Unrestricted cash
Cash and Cash Equivalents [Member]
Award Timing MNPI Disclosure
Award Timing MNPI Disclosure [Text Block]
Commitments to fund future advances
Contractual Obligation
Expected credit rate spreads on underlying loans
Expected Credit Loss Rate (Liabilities) [Abstract]
Expected Credit Loss Rate (Liabilities)
Aggregate Pension Adjustments Service Cost
Aggregate Pension Adjustments Service Cost [Member]
Beneficial interest assets included in payable to investors
Issuance Of Beneficial Interests
Issuance Of Beneficial Interests
Proceeds from sale of loans held-for-sale
Proceeds from Sale, Loan, Held-for-Sale
Unrecognized stock-based compensation expense related to unvested stock options
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount
As Previously Reported
Previously Reported [Member]
2025
Finite-Lived Intangible Asset, Expected Amortization, Year One
RSUs granted (in shares)
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period
Risk free rate, minimum
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum
Expected volatility, maximum
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum
Total revenue
Revenues
Conversion price maximum threshold
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger
Stockholders’ Equity
Share-Based Payment Arrangement [Text Block]
Securitizations
Securitizations [Member]
Securitizations
Expected prepayment rates
Expected Prepayment Rates [Abstract]
Expected Prepayment Rates
Entity Address, City or Town
Entity Address, City or Town
2029 Notes
Twenty Twenty Nine Notes [Member]
Twenty Twenty Nine Notes
Number of vesting tranches
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Number Of Vesting Tranches
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Number Of Vesting Tranches
Aggregate intrinsic value of options exercised
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period, Intrinsic Value
Stock-based compensation expense
Share-Based Payment Arrangement, Expense
20% adverse change
Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 20 Percent Adverse Change in Prepayment Speed
Options granted (in dollars per share)
Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price
Proceeds from sale of loans held-for-investment
Proceeds from Sale, Loan, Held-for-Investment
Loss Contingencies [Table]
Loss Contingencies [Table]
RSUs cancelled and forfeited (in shares)
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period
Business Acquisition [Axis]
Business Acquisition [Axis]
Schedule of Acquired Intangible Assets
Schedule of Finite-Lived Intangible Assets [Table Text Block]
Servicing fees
Servicing Fees [Member]
Servicing Fees
Proceeds from issuance of common stock under employee stock purchase plan
Proceeds, Issuance of Shares, Share-Based Payment Arrangement, Excluding Option Exercised
Gain on loan servicing rights, net
Gain (Loss) On Loan Servicing Rights And Sale Of Noncontrolling Interests, Net
Gain (Loss) On Loan Servicing Rights And Sale Of Noncontrolling Interests, Net
Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year
Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member]
Liabilities
Liabilities, Fair Value Disclosure [Abstract]
Revenue
Revenue from Contract with Customer [Text Block]
Document Fiscal Year Focus
Document Fiscal Year Focus
Change in fair value of beneficial interest liabilities
Increase (Decrease) In Fair Value Of Beneficial Interest Liabilities
Increase (Decrease) In Fair Value Of Beneficial Interest Liabilities
Debt Instrument, Name [Domain]
Debt Instrument, Name [Domain]
Servicing Asset at Fair Value, Amount [Roll Forward]
Servicing Asset at Fair Value, Amount [Roll Forward]
Total assets
Assets, Fair Value Disclosure
Remaining 2024
Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year
Proceeds from issuance of securitization notes
Net cash proceeds
Proceeds from Accounts Receivable Securitization
Document Period End Date
Document Period End Date
Unpaid principal balance, liability
Beneficial Interest, Liability, Unpaid Principal Balance
Beneficial Interest, Liability, Unpaid Principal Balance
Additions
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Additions
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Additions
Total undiscounted lease payments
Lessee, Operating Lease, Liability, to be Paid
Repayments and other changes in fair value recorded in earnings
Servicing Asset At Fair Value, Repayments And Other Changes At Fair Value, Gain (Loss) Included In Earnings
Servicing Asset At Fair Value, Repayments And Other Changes At Fair Value, Gain (Loss) Included In Earnings
Awards outstanding (in shares)
Beginning balance (in shares)
Ending balance (in shares)
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number
Asset Class [Axis]
Asset Class [Axis]
Insider Trading Arrangements [Line Items]
Balance Sheet Components
Supplemental Balance Sheet Disclosures [Text Block]
2027
Lessee, Operating Lease, Liability, to be Paid, Year Three
Interest income
Interest income
Interest Income, Operating
Reclassifications
Reclassification, Comparability Adjustment [Policy Text Block]
Change in fair value of servicing liabilities
Increase (Decrease) In Fair Value Of Servicing Liabilities
Increase (Decrease) In Fair Value Of Servicing Liabilities
Document Transition Report
Document Transition Report
10% adverse change
Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 10 Percent Adverse Change in Prepayment Speed
Loan purchase obligation
Purchase Obligation
Schedule of Servicing Assets at Fair Value [Table]
Servicing Asset at Fair Value, Activity [Table]
Issuances
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Issuances
Customer [Domain]
Customer [Domain]
Entity Current Reporting Status
Entity Current Reporting Status
Accumulated Deficit
Retained Earnings [Member]
Initial Cap Price per Share, Subject to Certain Adjustments (in dollars per share)
Debt Instrument, Convertible, Capped Calls Initial Cap Price
Debt Instrument, Convertible, Capped Calls Initial Cap Price
Beneficial interest assets
Beneficial Interest, Asset, Fair Value
Beneficial Interest, Asset, Fair Value
Loans > 90 Days Past Due
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Capitalized software costs
Payments for Software
Restricted stock units outstanding
Unvested RSUs
Restricted Stock Units (RSUs) [Member]
Sale of loans
Servicing Asset at Fair Value, Additions
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Executive Category:
Executive Category [Axis]
Actual payments
Loss Contingency Accrual, Payments
Prepaid expenses
Prepaid Expense
Servicing Liabilities at Fair Value [Line Items]
Servicing Liabilities at Fair Value [Line Items]
Fair value of options vested during period
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested in Period, Fair Value
Income Statement Location [Domain]
Statement of Income Location, Balance [Domain]
Company Selected Measure Name
Company Selected Measure Name