v3.26.1
Accounting policies - Foreign Currency (Details) - USD ($)
3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Foreign currency      
Net foreign currency gains $ 34,836 $ 29,642  
Cash and cash equivalents      
Money market fund 18,300,000   $ 18,100,000
Deposits held in foreign bank 11,900,000   12,000,000
Certificate of deposit      
Cash and cash equivalents      
Cash and cash equivalents $ 17,100,000   $ 17,000,000