XML 11 R1.htm IDEA: XBRL DOCUMENT v3.25.2
Document and Entity Information - shares
 6 Months Ended
Jun. 30, 2025
Aug. 06, 2025
Document and Entity Information    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jun. 30, 2025  
Document Transition Report false  
Entity File Number 001-35521  
Entity Registrant Name CLEARSIGN TECHNOLOGIES CORPORATION  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 26-2056298  
Entity Address, Address Line One 8023 E. 63rd Place, Suite 101  
Entity Address, City or Town Tulsa  
Entity Address, State or Province OK  
Entity Address, Postal Zip Code 74133  
City Area Code 918  
Local Phone Number 236-6461  
Title of 12(b) Security Common Stock  
Trading Symbol CLIR  
Security Exchange Name NASDAQ  
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 Common Stock, Shares Outstanding   52,426,282
Entity Central Index Key 0001434524  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q2  
Amendment Flag false