XML 14 R1.htm IDEA: XBRL DOCUMENT v3.19.3
Document and Entity Information - shares
 9 Months Ended
Sep. 30, 2019
Nov. 08, 2019
Document Information [Line Items]    
Entity Registrant Name PLUS THERAPEUTICS, INC.  
Entity Central Index Key 0001095981  
Current Fiscal Year End Date --12-31  
Entity Filer Category Non-accelerated Filer  
Entity Emerging Growth Company false  
Entity Small Business true  
Entity Common Stock, Shares Outstanding   3,770,588
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q3  
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Sep. 30, 2019  
Document Quarterly Report true  
Document Transition Report false  
Entity Interactive Data Current Yes  
Entity Current Reporting Status Yes  
Entity Shell Company false  
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  
Common Stock, par value $0.001 [Member]    
Document Information [Line Items]    
Trading Symbol PSTV  
Title of 12(b) Security Common Stock, par value $0.001  
Security Exchange Name NASDAQ  
Series S Warrant [Member]    
Document Information [Line Items]    
Trading Symbol PSTVZ  
Title of 12(b) Security Series S Warrant  
Security Exchange Name NASDAQ