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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Borrowings - Additional Information (Details) $ in Thousands, ¥ in Millions			3 Months Ended
	Jul. 05, 2024 USD ($)	Feb. 05, 2024 USD ($)	Mar. 31, 2025 USD ($)	Mar. 31, 2025 CNY (¥)	Jan. 22, 2025 USD ($)	Jan. 02, 2025 USD ($)	Jan. 02, 2025 CNY (¥)	Dec. 31, 2024 USD ($)	Jul. 05, 2024 CNY (¥)	Jun. 20, 2024 USD ($)	Mar. 31, 2024 USD ($)	Feb. 06, 2024 USD ($)	Feb. 06, 2024 CNY (¥)
Short-Term Debt [Line Items]
Restricted cash, current			$ 100,000					$ 100,000
Short-term debt			173,405					$ 131,711
SPD Bank
Short-Term Debt [Line Items]
Maximum guarantor obligation												$ 42,000	¥ 300.0
Guarantor obligation term												3 years	3 years
CMB
Short-Term Debt [Line Items]
Maximum guarantor obligation	$ 34,400								¥ 250.0
BOCOM
Short-Term Debt [Line Items]
Maximum guarantor obligation						$ 41,100	¥ 300.0
Bank of China Working Capital Loans
Short-Term Debt [Line Items]
Debt instrument fee											$ 700
Bank of China Working Capital Loans \| Loans Payable
Short-Term Debt [Line Items]
Short-term debt			$ 48,132
Bank of China Working Capital Loans \| Loans Payable \| Zai Lab Shanghai
Short-Term Debt [Line Items]
Debt instrument term			1 year
Short-term debt			$ 48,100	¥ 345.5
Floating interest rate adjustment period			6 months
SPD Bank Working Capital Loans \| Loans Payable
Short-Term Debt [Line Items]
Short-term debt			$ 41,793
SPD Bank Working Capital Loans \| Loans Payable \| Zai Lab Shanghai
Short-Term Debt [Line Items]
Debt instrument term			1 year
Short-term debt			$ 41,800	300.0
China Merchant Bank Working Capital Loans \| Loans Payable
Short-Term Debt [Line Items]
Short-term debt			$ 34,799
China Merchant Bank Working Capital Loans \| Loans Payable \| Zai Lab Shanghai
Short-Term Debt [Line Items]
Maximum borrowing capacity \| ¥									¥ 250.0
Debt instrument term	1 year		1 year
Short-term debt			$ 34,800	249.8
Floating interest rate adjustment period			3 months
Bank of Communications Working Capital Loans \| Loans Payable
Short-Term Debt [Line Items]
Short-term debt			$ 41,793
Bank of Communications Working Capital Loans \| Loans Payable \| Zai Lab Shanghai
Short-Term Debt [Line Items]
Debt instrument term			1 year
Short-term debt			$ 41,800	300.0
Floating interest rate adjustment period			3 months
Ningbo Bank Electronic Commercial Draft Discounting Agreement \| Loans Payable
Short-Term Debt [Line Items]
Maximum borrowing capacity												$ 22,500	¥ 160.0
Short-term debt			$ 6,888
Ningbo Bank Electronic Commercial Draft Discounting Agreement \| Loans Payable \| Zai Lab Suzhou
Short-Term Debt [Line Items]
Maximum borrowing capacity												$ 32,400	¥ 230.3
Short-term debt			$ 6,900	¥ 49.4
Standby Letters of Credit \| Bank of China Working Capital Loans
Short-Term Debt [Line Items]
Maximum borrowing capacity		$ 100,000
Debt instrument term		1 year
Letters of credit outstanding					$ 27,000					$ 23,000