Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Fair Value of Financial Assets and Liabilities - Additional Information (Details)

v3.23.1

Fair Value of Financial Assets and Liabilities - Additional Information (Details) - USD ($)			3 Months Ended	26 Months Ended
	Mar. 15, 2023	Jan. 21, 2020	Mar. 31, 2023	Mar. 31, 2023
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative liability for the exchange option, fair value			$ 63,000	$ 63,000
Derivative liability, change of control feature, fair value			124,000	124,000
RLNs liability			19,258,000	19,258,000
Fair value, asset measurement levels transfers amount			0
Fair value, liabilities measurement levels transfers amount			0
Exchangeable Notes
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Aggregate principal amount of exchangeable notes				39,201,000
Private Placement \| Securities
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Debt instrument price per ordinary share	$ 11.3107	$ 15.00
Debt instrument, shares embedded within each unit, shares	88.4122	66.666
Debt instrument, shares embedded within each unit, value	$ 1,000	$ 1,000
Private Placement \| Exchangeable Notes
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Aggregate principal amount of exchangeable notes			$ 39,201,000
Debt instrument, aggregate number of shares exchanged			3,592,555
Debt instrument, outstanding principal			$ 12,607,000	$ 12,607,000
Private Placement \| RLNs
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Debt instrument, aggregate potential payment capped value		160.00
Debt instrument, aggregate potential payment capped rate		4,000 times
Debt instrument, discount rate applied for royalty linked notes		22.00%

- Definition

Debt instrument aggregate amount of payment on royalty linked subordinated.

+ References

No definition available.

+ Details

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- Definition

Debt instrument aggregate potential payment capped rate.

+ References

No definition available.

+ Details

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- Definition

Debt instrument, discount rate applied for royalty linked notes.

+ References

No definition available.

+ Details

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- Definition

Debt instrument price per ordinary share

+ References

No definition available.

+ Details

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- Definition

Debt instrument shares embedded within each unit shares.

+ References

No definition available.

+ Details

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- Definition

Debt instrument shares embedded within each unit value.

+ References

No definition available.

+ Details

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- Definition

Debt repayment or conversion amount.

+ References

No definition available.

+ Details

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Namespace Prefix:	itrm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Derivative liability, change of control feature, fair value.

+ References

No definition available.

+ Details

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Namespace Prefix:	itrm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Derivative liability exchange option fair value.

+ References

No definition available.

+ Details

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Namespace Prefix:	itrm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Royalty linked notes noncurrent fair value.

+ References

No definition available.

+ Details

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

- Definition

The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 470
-SubTopic 20
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- 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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- Definition

Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

+ References

No definition available.

+ Details

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- Definition

Amount of transfers of financial instrument classified as a liability into (out of) level 3 of the fair value hierarchy.

+ References

No definition available.

+ Details

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