Quarterly report [Sections 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)

v3.25.1

Fair Value of Financial Assets and Liabilities - Additional Information (Details) - USD ($)			3 Months Ended		48 Months Ended
	Jan. 31, 2025	Jan. 21, 2020	Mar. 31, 2025	Mar. 31, 2024	Jan. 31, 2025
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Aggregate principal amount of exchangeable notes					$ 40,691,000
RLNs liability			$ 11,320,000
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]
Repayment of aggregate principal amount	$ 11,117,000
Accrued interest balance amount	3,628,000
Aggregate principal amount of exchangeable notes	$ 11,117,000				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
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

Accrued interest balance amount.

+ References

No definition available.

+ Details

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

- Definition

Debt instrument aggregate amount of payment on royalty linked subordinated.

+ References

No definition available.

+ Details

Name:	itrm_DebtInstrumentAggregateAmountOfPaymentOnRoyaltyLinkedSubordinated
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

Name:	itrm_DebtInstrumentAggregatePotentialPaymentCappedRate
Namespace Prefix:	itrm_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument, discount rate applied for royalty linked notes.

+ References

No definition available.

+ Details

Name:	itrm_DebtInstrumentDiscountRateAppliedForRoyaltyLinkedNotes
Namespace Prefix:	itrm_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- 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

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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of principal of debt repaid.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-03(i)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479886/946-10-S99-3

+ Details

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

- 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
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-3

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

+ Details

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

- Definition

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

+ References

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityTransfersNet
Namespace Prefix:	us-gaap_
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Balance Type:	credit
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- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: