Disposal group, including discontinued operation, additional gain recognized related to sale.

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Maximum aggregate consideration to be received upon achievement of certain regulatory and sales-based milestone events as well as royalties.

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The percentage of transfer of outstanding equity interest.

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Amount classified as assets attributable to disposal group held for sale or disposed of.

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Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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Amount classified as intangible assets, excluding goodwill, attributable to disposal group held for sale or disposed of.

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DISPOSAL OF TJBIO SHANGHAI - Additional Information (Details) - USD ($)		6 Months Ended		12 Months Ended
	Apr. 02, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Operational loss			$ (27,466,000)
Gain from sale			34,364,000
TJBio Shanghai [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Maximum aggregate consideration to be received upon achievement of certain regulatory and sales-based milestone events as well as royalties	$ 80,000,000
Operational loss			$ 6,898,000	$ (6,900,000)
Gain from sale				34,400,000
Carrying value of intangible assets				$ 16,200,000
Additional gain recognized related to sale		$ 0
Income tax expense or benefit	0
TJBio Shanghai [Member] \| Assets Held for Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Carrying value of assets classified as held for sale	33,100,000
TJBio Shanghai [Member] \| Liabilities Held for Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Carrying value of liabilities classified as held for sale	$ 83,700,000
I Mab Shanghai [Member] \| Imab Hangzhou [Member] \| Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Percentage of transfer of outstanding equity interest	100.00%