v3.24.4
Stockholders' Equity (Deficit) - September 2024 Securities Purchase Agreement (Q3) (Details) - USD ($)
$ / shares in Units, $ in Thousands
9 Months Ended 12 Months Ended
Sep. 15, 2024
Mar. 04, 2024
Jan. 12, 2024
Nov. 09, 2023
Oct. 02, 2023
Sep. 07, 2023
Feb. 27, 2023
Sep. 30, 2024
Sep. 30, 2023
Dec. 31, 2023
Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Number of warrants exercised on net basis (in shares)       2,904,269              
Exercise price (in dollars per share)     $ 0.96 $ 2              
Aggregate cost $ 2,800 $ 4,000 $ 4,000   $ 4,000 $ 5,000 $ 10,000        
Agent fees and other offering costs 300 500 400   400 400 700 $ 1,137 $ 1,135 $ 2,048 $ 0
Proceeds from issuance of warrants $ 2,400 $ 3,500 $ 3,600 $ 6,500 $ 3,600 $ 4,600 $ 9,300        
September Prefunded Warrants                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Number of warrants exercised on net basis (in shares)                   462,948  
Exercise price (in dollars per share) $ 0.00001                    
Warrant exercise term after issuance 6 months                    
March Warrants                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Number of warrants exercised on net basis (in shares)   4,624,280                  
Exercise price (in dollars per share)   $ 0.74                  
Placement Agent Warrants                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Class of warrant or right, gross proceeds and issued warrants percentage (as percent) 7.00%                    
First term 18 months                    
Estimated fair value of warrants $ 100                    
Common Class A                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Number of warrants exercised on net basis (in shares) 10,000,000                    
Purchase price (in dollars per share) $ 0.55 $ 0.87 $ 1.09   $ 2 $ 7.43          
Exercise price (in dollars per share)               $ 575   $ 575  
Common Class A | September Prefunded Warrants                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Number of warrants exercised on net basis (in shares) 5,000,000                    
Exercise price (in dollars per share) $ 0.575                    
Common Class A | Placement Agent Warrants                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Number of warrants exercised on net basis (in shares) 500,000                    
Exercise price (in dollars per share) $ 0.6325                    
Common Class B                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Number of warrants exercised on net basis (in shares) 5,000,000