Annual report [Section 13 and 15(d), not S-K Item 405]

Stockholders??? Equity - Stock Option Activity (Details)

v3.26.1
Stockholders’ Equity - Stock Option Activity (Details) - USD ($)
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Exercise Price Per Share [Abstract]    
Outstanding, Exercise Price Lower Range Limit (usd per share) $ 0.71 $ 0.71
Outstanding, Exercise Price Upper Range Limit (usd per share) 8.61  
Granted, Exercise Price Lower Range Limit (usd per share) 2.14  
Granted, Exercise Price Upper Range Limit (usd per share) 8.61 $ 3.93
Exercised, Exercise Price Per Share, lower range limit (usd per share) 0.71  
Exercised, Exercise Price Per Share, upper range limit (usd per share) 3.93  
Canceled and Forfeited, Exercise Price Lower Range Limit (usd per share) 0.71  
Canceled and Forfeited, Exercise Price Upper Range Limit (usd per share) $ 3.48  
Tecogen    
Stock Options Outstanding [Roll Forward]    
Beginning (shares) 2,752,962  
Granted (shares) 279,836  
Exercised (in shares) (575,154) (100,000)
Canceled and forfeited (shares) (110,600)  
Ending (shares) 2,347,044 2,752,962
Exercisable (shares) 1,490,958  
Vested and expected to vest (shares) 2,218,631  
Weighted Average Exercise Price [Roll Forward]    
Beginning (usd per share) $ 1.14  
Granted (usd per share) 7.60  
Exercised (usd per share) 1.21  
Canceled and forfeited (usd per share) 0.95  
Ending (usd per share) 1.90 $ 1.14
Vested and expected to vest (usd per share) 1.84  
Exercisable (usd per share) $ 1.24  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]    
Outstanding, Aggregate Intrinsic Value $ 7,961,973 $ 1,348,684
Exercised, Aggregate Intrinsic Value 2,144,534  
Exercisable, Aggregate Intrinsic Value 5,517,036  
Vested and expected to vest, Aggregate Intrinsic Value $ 7,595,233  
Stock Options | Tecogen    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]    
Outstanding, Weighted Average Remaining Life 6 years 3 months 14 days 6 years 8 months 12 days