XML 13 R1.htm IDEA: XBRL DOCUMENT v3.22.0.1
Document and Entity Information - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Feb. 18, 2022
Jun. 30, 2021
Cover [Abstract]      
Entity Registrant Name PLUS THERAPEUTICS, INC.    
Entity Central Index Key 0001095981    
Trading Symbol PSTV    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Interactive Data Current Yes    
Entity Current Reporting Status Yes    
Entity Filer Category Non-accelerated Filer    
Entity Public Float     $ 30.8
Entity Common Stock, Shares Outstanding   22,175,025  
Document Fiscal Year Focus 2021    
Document Fiscal Period Focus FY    
Document Type 10-K    
Amendment Flag false    
Document Period End Date Dec. 31, 2021    
Entity Shell Company false    
Entity Small Business true    
Entity Emerging Growth Company false    
ICFR Auditor Attestation Flag false    
Title of 12(b) Security Common Stock, par value $0.001 per share    
Security Exchange Name NASDAQ    
Entity File Number 001-34375    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 33-0827593    
Entity Address, Address Line One 4200 MARATHON BLVD    
Entity Address, Address Line Two SUITE 200    
Entity Address, City or Town AUSTIN    
Entity Address, State or Province TX    
Entity Address, Postal Zip Code 78756    
City Area Code 737    
Local Phone Number 255-7194    
Document Annual Report true    
Document Transition Report false    
Auditor Firm ID 243    
Auditor Name BDO USA, LLP    
Auditor Location Austin, Texas    
Documents Incorporated by Reference Portions of the registrant’s definitive proxy statement for its 2022 Annual Meeting of Stockholders, which will be filed with the United States Securities and Exchange Commission within 120 days of December 31, 2021, are incorporated by reference into Part III of this Annual Report on Form 10-K.