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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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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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Amount of cash restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Debt Instrument, Variable Interest Rate, Adjustment, Period

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Borrowings - Additional Information (Details) $ in Thousands, ¥ in Millions			9 Months Ended
	Jul. 05, 2024 USD ($)	Feb. 05, 2024 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2024 CNY (¥)	Jul. 05, 2024 CNY (¥)	Jun. 20, 2024 USD ($)	Mar. 31, 2024 USD ($)	Feb. 06, 2024 USD ($)	Feb. 06, 2024 CNY (¥)	Dec. 31, 2023 USD ($)
Short-Term Debt [Line Items]
Restricted cash, current			$ 100,000							$ 0
Short-term debt			112,994							$ 0
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
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			$ 70,925
Bank of China Working Capital Loans \| Loans Payable \| Zai Lab Shanghai
Short-Term Debt [Line Items]
Debt instrument term			1 year
Short-term debt			$ 70,900	¥ 497.0
Floating interest rate adjustment period			6 months
SPD Bank Working Capital Loans \| Loans Payable
Short-Term Debt [Line Items]
Short-term debt			$ 14,271
SPD Bank Working Capital Loans \| Loans Payable \| Zai Lab Shanghai
Short-Term Debt [Line Items]
Debt instrument term			1 year
Short-term debt			$ 14,300	100.0
Ningbo Bank Working Capital Loan Facility \| Loans Payable
Short-Term Debt [Line Items]
Maximum borrowing capacity								$ 22,500	¥ 160.0
Ningbo Bank Working Capital Loan Facility \| Loans Payable \| Zai Lab Suzhou
Short-Term Debt [Line Items]
Maximum borrowing capacity								32,400	¥ 230.3
China Merchant Bank Working Capital Loans \| Loans Payable
Short-Term Debt [Line Items]
Short-term debt			$ 27,798
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			$ 27,800	¥ 194.8
Floating interest rate adjustment period			3 months
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						$ 23,000		$ 50,000