Commitment and Contingencies	3 Months Ended
Commitment and Contingencies	Mar. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Loan Purchase Obligation Under the Company’s loan agreements with certain bank partners, the banks retain ownership of the loans facilitated through Upstart’s platform for three days or longer (the “holding period”) after origination, as required under the respective agreements. The Company has committed to purchase the loans at the conclusion of the required holding period. As of December 31, 2021 and March 31, 2022, the total loan purchase commitment included outstanding principal balance of $111.3 million and $114.2 million, respectively. Repurchase and Indemnification Contingency Under the terms of the loan purchase and loan servicing agreements between the Company and institutional investors, as well as in agreements with investors in securitizations and pass-through certificate transactions, the Company may, in certain circumstances, become obligated to repurchase loans from such investors. Generally, these circumstances include the occurrence of verifiable identity theft, the failure of sold loans to meet the terms of certain loan-level representations and warranties that speak as of the time of origination or sale, the failure to comply with other contractual terms with the investors, or a violation of the applicable federal, state, or local lending laws. The maximum potential amount of future payments associated under this obligation is the outstanding balances of the loans sold to the investors, which at December 31, 2021 and March 31, 2022 is $12,905.5 million and $15,422.3 million, respectively. Actual payments made relating to the Company’s repurchase and indemnification obligations were immaterial historically. The Company has recorded contingent liabilities as of December 31, 2021 and March 31, 2022 of immaterial amounts to cover estimated future obligations related to these contractual terms. These amounts are included in accrued expenses and other liabilities on the Company’s condensed consolidated balance sheets. Legal From time to time the Company is subject to, and it is presently involved in, litigation and other legal proceedings. Accounting for contingencies requires the Company to use judgment related to both the likelihood of a loss and the estimate of the amount or range of loss. The Company records a loss contingency when it is probable that a liability has been incurred and the amount of the loss can be reasonably estimated. As of December 31, 2021 and March 31, 2022, no loss contingency has been recorded in connection with legal proceedings arising in the ordinary course of business. Contingencies Accounting for contingencies requires the Company to use judgment related to both the likelihood of a loss and the estimate of the amount or range of loss. The Company records a loss contingency when it is probable that a liability has been incurred and the amount of the loss can be reasonably estimated. The Company discloses material contingencies when it believes a loss is not probable but reasonably possible. Although the Company cannot reasonably determine the outcome of any litigation or tax matters, it does not believe there are currently any such actions that, if resolved unfavorably, would have a material impact on its condensed consolidated financial statements. Indemnifications In the ordinary course of business, the Company may provide indemnifications of varying scope and terms to vendors, directors, officers and other parties with respect to certain matters. In addition, the Company has entered into indemnification agreements with directors and certain officers and employees that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors, officers or employees. No demands have been made upon the Company to provide indemnification under such agreements, and thus, there are no claims that the Company is aware of that could have a material effect on the Company’s condensed consolidated financial statements.