Cover - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Mar. 04, 2022
Jun. 30, 2021
Cover [Abstract]        
Document Type 10-K      
Amendment Flag false      
Document Annual Report true      
Document Transition Report false      
Document Period End Date Dec. 31, 2021      
Document Fiscal Period Focus FY      
Document Fiscal Year Focus 2021      
Current Fiscal Year End Date --12-31      
Entity File Number 001-12830      
Entity Registrant Name Lineage Cell Therapeutics, Inc.      
Entity Central Index Key 0000876343      
Entity Tax Identification Number 94-3127919      
Entity Incorporation, State or Country Code CA      
Entity Address, Address Line One 2173 Salk Avenue      
Entity Address, Address Line Two Suite 200      
Entity Address, City or Town Carlsbad      
Entity Address, State or Province CA      
Entity Address, Postal Zip Code 92008      
City Area Code 442      
Local Phone Number 287-8990      
Title of 12(b) Security Common stock      
Trading Symbol LCTX      
Security Exchange Name NYSE      
Entity Well-known Seasoned Issuer No      
Entity Voluntary Filers No      
Entity Current Reporting Status Yes      
Entity Interactive Data Current Yes      
Entity Filer Category Non-accelerated Filer      
Entity Small Business true      
Entity Emerging Growth Company false      
Entity Shell Company false      
Entity Public Float       $ 356.8
Entity Common Stock, Shares Outstanding     169,709,292  
Documents Incorporated by Reference Portions of the registrant’s definitive proxy statement relating to its 2022 annual meeting of shareholders are incorporated by reference into Part III of this Annual Report on Form 10-K where indicated.      
ICFR Auditor Attestation Flag false      
Auditor Name WithumSmith+Brown, PC OUM & CO. LLP    
Auditor Location San Francisco, California San Francisco, California    
Auditor Firm ID 100 252