v3.26.1
Description of Business and Basis of Presentation - Business combination shares issued and outstanding (Details) - Legacy Deep Fission
Sep. 05, 2025
shares
Description of Business and Basis of Presentation  
Beginning balance (in shares) 38,538,922
Ending balance (in shares) 50,790,589
Legacy Surfside shareholders  
Description of Business and Basis of Presentation  
Shares issued 2,166,667
Advisor  
Description of Business and Basis of Presentation  
Shares issued 85,000
PIPE investors  
Description of Business and Basis of Presentation  
Shares issued 10,000,000