Cover Page - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2019	Feb. 28, 2020	Jun. 30, 2019
Cover page.
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2019
Document Transition Report	false
Entity File Number	001-34962
Entity Registrant Name	Zogenix, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-5300780
Entity Address, Address Line One	5959 Horton Street
Entity Address, Address Line Two	Suite 500
Entity Address, City or Town	Emeryville
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94608
City Area Code	510
Local Phone Number	550-8300
Title of 12(b) Security	Common Stock, $0.001 par value per share
Trading Symbol	ZGNX
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 1.8
Entity Common Stock, Shares Outstanding		45,378,246
Documents Incorporated by Reference	Portions of the registrant’s definitive Proxy Statement to be filed for its 2020 Annual Meeting of Stockholders are incorporated by reference into Part III of this Annual Report on Form 10-K. Such proxy statement will be filed with the Securities and Exchange Commission within 120 days of the registrant’s fiscal year ended December 31, 2019.
Entity Central Index Key	0001375151
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Amendment Flag	false