Reduction to research and development expense.

No definition available.

Name:	imnm_ContraResearchAndDevelopmentExpense
Namespace Prefix:	imnm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of deferred research obligation liability.

+ References

No definition available.

+ Details

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Namespace Prefix:	imnm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of grant expected to be received.

+ References

No definition available.

+ Details

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Namespace Prefix:	imnm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The period of payment of reimbursement under the contract.

+ References

No definition available.

+ Details

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Namespace Prefix:	imnm_
Data Type:	xbrli:durationItemType
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- Definition

Carrying amount as of the balance sheet date of amounts due under the terms of governmental, corporate, or foundation grants.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of amounts due under the terms of governmental, corporate, or foundation grants. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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- Details

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Namespace Prefix:
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Balance Type:
Period Type:

U.S. Department of Defense (DoD) expense reimbursement contract (Details) - Other Transaction Authority for Prototype Agreement - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Jul. 31, 2020	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	May 31, 2021
Unusual or Infrequent Item, or Both [Line Items]
Grants Receivable	$ 13.3				$ 17.6
Payment period of reimbursement contract	30 days
Contra-research and development expense		$ 0.6	$ 4.0
Prepaid expenses and other current assets		0.0		$ 2.7
Deferred research obligation liability		0.6		2.0
Grant expected to be received		0.8		$ 1.6
Grants receivable current		$ 0.2