v3.26.1
INVESTMENT IN EQUITY SECURITIES, AT FAIR VALUE AND LONG-TERM INVESTMENTS - Summary of Long-term investments (Details) - USD ($)
$ in Thousands
12 Months Ended 24 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2025
Schedule Of Long Term Investments      
Cost $ 2,581 $ 2,581 $ 2,581
Gross unrealized losses (including impairment) (865) (865)  
Carrying amount 1,716 1,716 1,716
Alesta Tx | Common Stock      
Schedule Of Long Term Investments      
Cost 2,250 2,250 2,250
Gross unrealized losses (including impairment)   (865) (865)
Carrying amount $ 1,385 $ 1,385 $ 1,385
Investment, Type [Extensible Enumeration] casi:EquitySecuritiesWithoutReadilyDeterminableFairValueMember casi:EquitySecuritiesWithoutReadilyDeterminableFairValueMember casi:EquitySecuritiesWithoutReadilyDeterminableFairValueMember
Alesta Tx | Preferred Stock      
Schedule Of Long Term Investments      
Cost $ 331 $ 331 $ 331
Carrying amount $ 331 $ 331 $ 331
Investment, Type [Extensible Enumeration] casi:EquitySecuritiesWithoutReadilyDeterminableFairValueMember casi:EquitySecuritiesWithoutReadilyDeterminableFairValueMember casi:EquitySecuritiesWithoutReadilyDeterminableFairValueMember