XML 67 R1.htm IDEA: XBRL DOCUMENT v3.20.1
Document and Entity Information - USD ($)
 12 Months Ended
Dec. 31, 2019
Mar. 02, 2020
Jun. 28, 2019
Cover [Abstract]      
Entity Registrant Name GERON CORP    
Entity Central Index Key 0000886744    
Document Type 10-K    
Document Period End Date Dec. 31, 2019    
Amendment Flag false    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Filer Category Accelerated Filer    
Entity Small Business true    
Entity Emerging Growth Company false    
Entity Public Float     $ 262,459,000
Entity Common Stock, Shares Outstanding   200,344,809  
Document Fiscal Year Focus 2019    
Document Fiscal Period Focus FY    
Trading Symbol GERN    
Entity File Number 0-20859    
Entity Tax Identification Number 75-2287752    
Entity Shell Company false    
Entity Address, Address Line One 149 Commonwealth Drive    
Entity Address, Address Line Two Suite 2070    
Entity Address, City or Town Menlo Park    
Entity Address, State or Province CA    
Entity Address, Postal Zip Code 94025    
City Area Code 650    
Local Phone Number 473-7700    
Entity Interactive Data Current Yes    
Title of 12(b) Security Common Stock, $0.001 par value    
Security Exchange Name NASDAQ    
Entity Incorporation, State or Country Code DE    
Document Annual Report true    
Document Transition Report false    
Documents Incorporated by Reference

Portions of the Registrant’s definitive proxy statement for the 2020 annual meeting of stockholders to be filed pursuant to Regulation 14A within 120 days of the Registrant’s fiscal year ended December 31, 2019