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)

v3.24.1.1.u2

Fair Value of Financial Assets and Liabilities - Additional Information (Details) - USD ($)		3 Months Ended	38 Months Ended
	Jan. 21, 2020	Mar. 31, 2024	Mar. 31, 2024
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative liability for the exchange option, fair value		$ 0	$ 0
Aggregate principal amount of exchangeable notes			40,691,000
RLNs liability		7,889,000	7,889,000
Fair value, asset Level 3 transfers amount		0
Fair value, liabilities Level 3 transfers amount		0
Exchangeable Notes
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Aggregate principal amount of exchangeable notes			40,691,000
Private Placement \| Exchangeable Notes
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Aggregate principal amount of exchangeable notes			$ 40,691,000
Debt instrument, aggregate number of shares exchanged			3,760,155
Debt instrument, outstanding principal		$ 11,117,000	$ 11,117,000
Private Placement \| Securities
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Debt instrument price per ordinary share	$ 15	$ 9.576
Debt instrument, shares embedded within each unit, shares	66.666	104.4282
Debt instrument, shares embedded within each unit, value	$ 1,000	$ 1,000
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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Namespace Prefix:	itrm_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument aggregate potential payment capped rate.

+ References

No definition available.

+ Details

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Namespace Prefix:	itrm_
Data Type:	xbrli:stringItemType
Balance Type:	na
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- Definition

Debt instrument, discount rate applied for royalty linked notes.

+ References

No definition available.

+ Details

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Namespace Prefix:	itrm_
Data Type:	dtr-types:percentItemType
Balance Type:	na
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- Definition

Debt instrument price per ordinary share

+ References

No definition available.

+ Details

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Namespace Prefix:	itrm_
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Balance Type:	na
Period Type:	duration

- Definition

Debt instrument shares embedded within each unit shares.

+ References

No definition available.

+ Details

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Namespace Prefix:	itrm_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument shares embedded within each unit value.

+ References

No definition available.

+ Details

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

- Definition

Debt repayment or conversion amount.

+ References

No definition available.

+ Details

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

- Definition

Derivative liability exchange option fair value.

+ References

No definition available.

+ Details

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

- Definition

Royalty linked notes noncurrent fair value.

+ References

No definition available.

+ Details

Name:	itrm_RoyaltyLinkedNotesNoncurrentFairValue
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
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482913/230-10-50-3

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-Section 50
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482913/230-10-50-5

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Period Type:	duration

- 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://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
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-Topic 942
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-Name Accounting Standards Codification
-Section S99
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-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-4

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
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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Data Type:	xbrli:stringItemType
Balance Type:	na
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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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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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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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- Details

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