XML 118 R1.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
Document and Entity Information - USD ($)
 12 Months Ended
Dec. 31, 2019
Feb. 19, 2020
Jun. 28, 2019
Document And Entity Information [Abstract]      
Title of 12(b) Security Common Stock, $0.0001 par value    
Entity Incorporation, State or Country Code DE    
Document Annual Report true    
Document Transition Report false    
Entity File Number 0-24006    
Document Type 10-K    
Amendment Flag false    
Document Period End Date Dec. 31, 2019    
Document Fiscal Year Focus 2019    
Document Fiscal Period Focus FY    
Trading Symbol NKTR    
Entity Registrant Name NEKTAR THERAPEUTICS    
Entity Central Index Key 0000906709    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer Yes    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Filer Category Large Accelerated Filer    
Entity Shell Company false    
Entity Small Business false    
Entity Emerging Growth Company false    
Entity Common Stock, Shares Outstanding   177,557,144  
Entity Public Float     $ 6,184,040,785
Entity Tax Identification Number 94-3134940    
Entity Address, Address Line One 455 Mission Bay Boulevard South    
Entity Address, City or Town San Francisco    
Entity Address, State or Province CA    
Entity Address, Postal Zip Code 94158    
City Area Code 415    
Local Phone Number 482-5300    
Security Exchange Name NASDAQ    
Entity Interactive Data Current Yes    
Documents Incorporated by Reference [Text Block] Portions of registrant’s definitive Proxy Statement to be filed for its 2019 Annual Meeting of Stockholders are incorporated by reference into Part III hereof. Such Proxy Statement will be filed with the Securities and Exchange Commission within 120 days of the end of the fiscal year covered by this Annual Report on Form 10-K.