Organization and Basis of Presentation	9 Months Ended
Organization and Basis of Presentation	Sep. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	Organization and Basis of Presentation Zogenix, Inc. and subsidiaries (the Company, we, us or our) is a global pharmaceutical company committed to developing and commercializing transformative therapies to improve the lives of patients and their families living with rare diseases. We are currently focused on developing and commercializing therapies to address rare or orphan disorders. Our lead product candidate, Fintepla (ZX008, fenfluramine) is currently being developed for the treatment of seizures associated with Dravet syndrome and Lennox-Gastaut syndrome (LGS). In September 2019, we acquired all of the outstanding equity interests in Modis Therapeutics, Inc. (Modis), a privately-held biopharmaceutical company. Modis’ lead product, MT1621, is an investigational deoxynucleoside substrate enhancement therapy in development for the treatment of thymidine kinase 2 deficiency (TK2d), an inherited mitochondrial DNA depletion disorder that predominantly affects children and is often fatal. See Note 3 for additional information. We operate in one business segment—the research, development and commercialization of pharmaceutical products and our headquarters are located in Emeryville, California. Basis of Presentation The accompanying condensed consolidated financial statements include the accounts of Zogenix, Inc. and its wholly-owned subsidiaries. Intercompany accounts and transactions have been eliminated in consolidation. The condensed consolidated financial statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (SEC) for interim financial reporting. In the opinion of management, the condensed consolidated financial statements reflect all adjustments, which are normal and recurring in nature, necessary for fair financial statement presentation. The results of operations for any interim period are not necessarily indicative of results of operations for any future period. Certain information and footnote disclosures normally included in annual consolidated financial statements prepared in accordance with generally accepted accounting principles in the United States (GAAP) have been condensed or omitted. Accordingly, these unaudited interim condensed consolidated financial statements and accompanying notes should be read in conjunction with the consolidated financial statements and related notes included in our 2018 Annual Report on Form 10-K, which was filed with the SEC on February 28, 2019. Certain prior period amounts within the accompanying unaudited condensed consolidated financial statements have been reclassified to conform to current period presentation. These reclassifications did not affect our financial position, net loss, comprehensive loss, or cash flows as of and for the periods presented. Our accompanying condensed consolidated financial statements include the assets acquired and liabilities assumed in connection with the acquisition of Modis, in addition to the operating results and cash flows, beginning with the date of the acquisition. Future Funding Requirements Excluding gains from two discrete business divestitures, we have incurred significant net losses and negative cash flows from operating activities since inception resulting in an accumulated deficit of $1.1 billion as of September 30, 2019. We expect to continue to incur significant operating losses and negative cash flows from operations as we continue to advance our product candidates through development and commercialization. Additionally, pursuant to our acquisition of Brabant Pharma Limited (Brabant) in 2014 to obtain worldwide development and commercialization rights to Fintepla, we are required to make additional payments to the former shareholders of Brabant in the event we achieve certain regulatory and sales milestones with Fintepla (See Note 6). Pursuant to our asset acquisition of Modis in September 2019, we are required to make additional payments to the former shareholders of Modis in the event we achieve certain regulatory milestones (See Note 3). Historically, we have relied primarily on the proceeds from equity offerings to finance our operations. Until such time, if ever, we can generate a sufficient amount of revenue to finance our cash requirements, we may need to continue to rely on additional financing to achieve our business objectives. However, if such financing is not available at adequate levels when needed, we may be required to significantly delay, scale back or discontinue one or more of our product development programs or commercialization efforts or other aspects of our business plans, and our operating results and financial condition would be adversely affected.