Subsequent Events	6 Months Ended
Jun. 30, 2025
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On August 6, 2025, the Company entered into a new revolving credit facility with CMB, which replaced its previous RMB250.0 million (approximately $34.4 million) credit facility that expired in July 2025. The Company issued a new maximum-amount irrevocable letter of guarantee to CMB pursuant to which the Company will guarantee working capital loans of up to RMB500.0 million (approximately $69.6 million) from CMB to Zai Lab Shanghai, and Zai Lab Shanghai entered into a Credit Agreement with CMB with respect to the RMB500.0 million facility. The new guarantee and credit facility include the outstanding working capital loans with CMB. The credit facility will be available for two years, and key terms of the specific working capital loans, including the amount, term, and interest rate, will be included in the specific transaction documents.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/855/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

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