Prepaid expenses and other current assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Prepaid expenses and other current assets
Reimbursement receivable from DoD	$ 2,674	$ 850
Prepaid insurance	2,019	1,767
Unbilled reimbursement receivable from DoD	1,638
Research and development advance payments	586
Other prepaids and short term deposits	492	511
Prepaid expenses and other current assets	$ 7,409	$ 3,128

The amount of reimbursement receivable classified as current.

No definition available.

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- Definition

The advance payments for research and development expenses.

+ References

No definition available.

+ Details

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- Definition

The amount of unbilled reimbursement receivable classified as current.

+ References

No definition available.

+ Details

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

- References

No definition available.

+ Details

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- Definition

Amount of asset related to consideration paid in advance for other costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

+ References

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- Definition

Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of asset related to consideration paid in advance for insurance that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

+ References

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-Publisher FASB
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+ Details

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Balance Type:	debit
Period Type:	instant