v3.26.3
Stock-based Compensation (FY) (Details)
1 Months Ended 3 Months Ended 6 Months Ended 12 Months Ended 62 Months Ended
Apr. 30, 2021
shares
Apr. 30, 2021
shares
Jun. 30, 2026
USD ($)
shares
Jun. 30, 2025
$ / shares
shares
Jun. 30, 2026
USD ($)
shares
Jun. 30, 2025
$ / shares
shares
Dec. 31, 2025
USD ($)
$ / shares
shares
Dec. 31, 2024
USD ($)
$ / shares
shares
Dec. 31, 2021
Jun. 30, 2026
USD ($)
shares
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]                    
Common stock available for issuance (in shares)     15,321,133   15,321,133   13,346,191 10,838,390   15,321,133
Granted (in shares)     0   0          
Weighted-average grant date fair value of awards (in Dollars per share) | $ / shares       $ 0.82   $ 1.17        
Stock option exercises (in shares)     0 0 0 0 0      
Share-based compensation expense not yet recognized (in Dollars) | $     $ 2,000,000   $ 2,000,000   $ 5,400,000     $ 2,000,000
2026 Restructuring Plan                    
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]                    
One-time charge related to modification (in Dollars) | $     $ 100,000   $ 700,000          
2021 Stock Incentive Plan                    
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]                    
Maximum number of shares to be added annually, as a percentage of outstanding shares (percent) 0.05                  
Common stock available for issuance (in shares)             2,039,026      
Maximum number of shares to be added annually, as a percentage of outstanding shares (percent)   5.00%                
2021 Stock Employee Stock Purchase Plan                    
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]                    
Offering period                 6 months  
Purchase period                 6 months  
ESPP purchase price, percent                 0.85  
Common Stock                    
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]                    
Common stock authorized to be issued (in shares) 3,352,725 3,352,725                
Stock option exercises (in shares)               17,224    
Common Stock | 2021 Stock Incentive Plan                    
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]                    
Common stock authorized to be issued (in shares) 2,843,116 2,843,116                
Maximum number of shares to be added annually, as a percentage of outstanding shares (in shares)             7,152,859     9,582,699
Common Stock | 2017 Stock Incentive Plan                    
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]                    
Common stock authorized to be issued (in shares) 31,884 31,884                
Common Stock | 2021 Stock Employee Stock Purchase Plan                    
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]                    
Shares purchased by employees         2,249 39,853 96,470 73,849    
Shares purchased by employees, value (in Dollars) | $             $ 100,000 $ 100,000    
Common stock to be issued upon exercise of the K2HV Loan Agreement conversion feature | 2021 Stock Incentive Plan                    
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]                    
Common stock authorized to be issued (in shares) 477,725 477,725                
Inducement Stock Option                    
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]                    
Granted (in shares)             201,720 0    
Unvested RSUs                    
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]                    
Aggregate fair value of awards that vested (in Dollars) | $               $ 1,000,000    
Unvested RSUs | 2021 Stock Incentive Plan                    
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]                    
Granted (in shares)             0      
Share-based compensation expense not yet recognized (in Dollars) | $             $ 0      
Shares reserved for issuance under the 2021 Stock Incentive Plan                    
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]                    
Granted (in shares)             3,390,691      
Expected annual dividend yield       0.00%   0.00% 0.00% 0.00%    
Weighted-average grant date fair value of awards (in Dollars per share) | $ / shares             $ 1.16 $ 3.43    
Stock option exercises (in shares)             0      
Aggregate intrinsic fair value of options exercised (in Dollars) | $               $ 0    
Share-based compensation not yet recognized, recognition period         1 year 8 months 12 days   1 year 10 months 24 days      
Stock option expiration period upon termination         90 days          
Shares reserved for issuance under the 2021 Stock Incentive Plan | 2026 Restructuring Plan                    
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]                    
Stock option expiration period         10 years