Basis of Presentation and Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2020
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (“U.S. GAAP”) and applicable rules and regulations of the SEC regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to such rules and regulations. As such, the information included in this Quarterly Report should be read in conjunction with the consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2019 (the “Annual Report”), filed with the SEC on March 2, 2020. The condensed consolidated balance sheet as of December 31, 2019 included herein was derived from the audited financial statements as of that date, but does not include all disclosures including notes required by U.S. GAAP. The condensed consolidated financial statements include the accounts of Upwork Inc. and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated. The accompanying condensed consolidated financial statements reflect all normal recurring adjustments necessary to present fairly the financial position, results of operations, changes in stockholders’ equity and cash flows for the interim periods, but do not purport to be indicative of the results of operations or financial condition to be anticipated for the full year ending December 31, 2020.
Use of Estimates	Use of Estimates The preparation of the condensed consolidated financial statements in conformity with U.S. GAAP requires management to make certain estimates, judgments, and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenue and expenses during the periods presented. Such estimates include, but are not limited to: the useful lives of assets; assessment of the recoverability of long-lived assets; goodwill impairment; standalone selling price of material rights and the period of time over which to defer and recognize the consideration allocated to the material rights; allowance for doubtful accounts; liabilities relating to transaction losses; the valuation of warrants; stock-based compensation; and accounting for income taxes. Management bases its estimates on historical experience and on various other assumptions that management believes to be reasonable under the circumstances. The Company evaluates its estimates, assumptions, and judgments on an ongoing basis using historical experience and other factors and revises them when facts and circumstances dictate.
Recently Adopted Accounting Pronouncements and Recent Accounting Pronouncements Not Yet Adopted	Recently Adopted Accounting Pronouncements The significant accounting policies applied in the Company’s audited consolidated financial statements, as disclosed in the Annual Report, are applied consistently in these unaudited interim condensed consolidated financial statements, except as noted below. In June 2016, the Financial Accounting Standards Board (the “FASB”) issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. This standard changes the methodology for measuring credit losses on financial instruments and the timing of when such losses are recorded. The Company adopted ASU No. 2016-13 and related updates on January 1, 2020. The adoption did not have a material impact on the Company’s condensed consolidated financial statements. In January 2017, the FASB issued ASU No. 2017-04, Intangibles—Goodwill and Others (Topic 350): Simplifying the Test for Goodwill Impairment. ASU No. 2017-04 eliminates Step 2 from the goodwill impairment test, which measures a goodwill impairment loss by comparing the implied fair value of a reporting unit’s goodwill with the carrying amount of that goodwill. The Company adopted ASU No. 2017-04 on January 1, 2020. The adoption did not have a material impact on the Company’s condensed consolidated financial statements. In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement, which modifies the disclosure requirements on fair value measurements. The Company adopted ASU No. 2018-13 on January 1, 2020. The adoption did not have a material impact on the Company’s condensed consolidated financial statements. In August 2018, the FASB issued ASU No. 2018-15, Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. ASU No. 2018-15 aligns the requirements for capitalizing implementation costs in a cloud computing arrangement service contract with the requirements for capitalizing implementation costs incurred for an internal-use software license. The Company adopted ASU No. 2018-15 on January 1, 2020 using the prospective adoption method. The adoption did not have a material impact on the Company’s condensed consolidated financial statements. Recent Accounting Pronouncements Not Yet Adopted The Company has reviewed all other accounting pronouncements issued during the nine months ended September 30, 2020 and concluded they were either not applicable or not expected to have a material impact on the Company’s condensed consolidated financial statements.