v3.25.4
Income Tax - Additional Information (Details) - USD ($)
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Income Tax Disclosure [Line Items]      
Taxable income $ (178,464,000) $ (257,103,000) $ (334,620,000)
Provision for income taxes (2,927,000) 0 0
Deferred tax assets, net 3,390,000 0  
Net operating loss carry forwards 2,121,678,000 1,951,500,000  
Mainland China      
Income Tax Disclosure [Line Items]      
Income taxes paid, net 0 0 0
Zai Lab (AUST) Pty. Ltd.      
Income Tax Disclosure [Line Items]      
Taxable income 0    
Provision for income taxes 0    
Zai Lab (US) LLC      
Income Tax Disclosure [Line Items]      
Taxable income 0    
Provision for income taxes 0    
Zai Lab (Taiwan) Limited      
Income Tax Disclosure [Line Items]      
Taxable income 0    
Provision for income taxes 0    
Zai Lab (Hong Kong) and ZL China Holding Two and Zai Auto Immune (Hong Kong) and Zai Anti Infectives (Hong Kong) Limited      
Income Tax Disclosure [Line Items]      
Taxable income 0 0 0
Provision for income taxes 0 0 0
Withholding taxes on remittance of dividends $ 0 $ 0 $ 0