American depositary share authorized for issuance.

No definition available.

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- Definition

Deposit received.

+ References

No definition available.

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- Definition

Milestone payments received for development and regulatory milestones.

+ References

No definition available.

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- Definition

Non contingent payments.

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No definition available.

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- Definition

The percentage of transfer of outstanding equity interest.

+ References

No definition available.

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- Definition

Representing the upfront payment received.

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No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-28

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
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-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481687/323-10-50-3

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- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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No definition available.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 718
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-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481674/830-30-50-2

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

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SUBSEQUENT EVENTS (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	3 Months Ended	27 Months Ended
	Aug. 05, 2025	Apr. 02, 2024	Sep. 30, 2025	Dec. 31, 2025	Dec. 31, 2027	Sep. 03, 2025
Segment Discontinued Operations \| I-Mab Shanghai \| I-Mab Hangzhou
Subsequent Event [Line Items]
Percentage of transfer of outstanding equity interest		100.00%
Subsequent Event
Subsequent Event [Line Items]
Upfront payment				$ 1,800
Subsequent Event \| Bridge Health Biotech Co., Ltd [Member]
Subsequent Event [Line Items]
Equity purchase agreement percentage				100.00%
Non contingent payments					$ 1,200
Milestone payments received for development and regulatory milestones				$ 3,875
Subsequent Event \| TJ Biopharma
Subsequent Event [Line Items]
Deposit received			$ 7,200
Subsequent Event \| Ordinary Shares
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares)	76,666,659
Net proceeds from underwritten offering	$ 61,200
Subsequent Event \| Ordinary Shares \| 2025 Omnibus Share Incentive Plan
Subsequent Event [Line Items]
Share based payment award, maximum shares authorized						18,810,820
Subsequent Event \| Ordinary Shares \| 2025 Omnibus Share Incentive Plan \| Maximum
Subsequent Event [Line Items]
Share based payment award, maximum shares authorized						13,238,741
Subsequent Event \| American Depositary Share
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares)	33,333,330
Per share price of issuance (in usd per share)	$ 1.95
Subsequent Event \| American Depositary Share \| 2025 Omnibus Share Incentive Plan
Subsequent Event [Line Items]
American depositary share authorized for issuance						8,178,617