Contractual agreement cancelation notice period

No definition available.

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- Definition

Expected cost of terminated leases.

+ References

No definition available.

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Balance Type:	debit
Period Type:	duration

- Definition

Lease commencement date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of hand serving to secure obligation under the operating lease.

+ References

No definition available.

+ Details

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

- Definition

Amount of the letter of credit provided to the lessor to secure obligation under the operating lease.

+ References

No definition available.

+ Details

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Namespace Prefix:	itos_
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Balance Type:	credit
Period Type:	instant

- Definition

Operating leases rent expense net 1.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Area of land subject to a ground lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

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Period Type:	instant

- Definition

Date which lease or group of leases is set to expire, in YYYY-MM-DD format.

+ References

No definition available.

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Indicates (true false) whether lessee has option to extend operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

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Balance Type:	na
Period Type:	duration

- Definition

Indicates (true false) whether lessee has option to terminate operating lease.

+ References

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- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-1

+ Details

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

- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (a)
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-URI https://asc.fasb.org/1943274/2147479041/842-20-45-1

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

- Definition

Description of the nature and terms of commitment.

+ References

No definition available.

+ Details

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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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Balance Type:	na
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- Definition

The amount of cash paid for royalties during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Paragraph 25
-Subparagraph (g)
-SubTopic 10
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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

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Balance Type:	debit
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- Details

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- Details

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- Details

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- Details

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Commitments and Contingencies - Additional Information (Details)	1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Jul. 31, 2025 USD ($)	Jun. 30, 2025 USD ($) ft² m²	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) ft² m²	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)	Nov. 30, 2021 USD ($)
Other Commitments [Line Items]
Restructuring charges		$ 16,335,000	$ 0	$ 16,335,000	$ 0
Land subject to leases \| m²		2,684		2,684
Right of use assets		$ 5,129,000		$ 5,129,000		$ 5,089,000
Liability		5,128,000		5,128,000
Expected cost of terminated leases	$ 2,400,000			2,400,000
Operating leases, rent expense		400,000	$ 800,000	$ 400,000	$ 800,000
Extension of office lease				In January 2021, the Company entered into an amendment to extend the lease, effective February 2021 with a termination date of January 2030.
Wu Xi Agreement
Other Commitments [Line Items]
Minimum commitments		0		$ 0		0
Payments for Royalties				0		0
Gosselies, Belgium
Other Commitments [Line Items]
Operating lease, Hand serving to secure lease obligation		$ 177,000		$ 177,000		156,000
Watertown Massachusetts [Member]
Other Commitments [Line Items]
Land subject to leases \| ft²		9,068		9,068
Operating lease, Letter of credit to secure lease obligation							$ 142,000
Office and Laboratory Space \| Gosselies, Belgium
Other Commitments [Line Items]
Lease commencement date				May 31, 2016
Lessee, operating lease, existence of option to extend [true false]				false
Lessee, operating lease, existence of option to terminate [true false]				false
Office and Laboratory Space \| Gosselies, Belgium \| Agreement To Extend Lease Member
Other Commitments [Line Items]
Lease commencement date				Feb. 28, 2021
Lease expiration date				Jan. 31, 2030
Office \| Cambridge, Massachusetts
Other Commitments [Line Items]
Lease expiration date				Feb. 28, 2027
Office \| Watertown Massachusetts [Member]
Other Commitments [Line Items]
Lease commencement date				Nov. 30, 2021
Laboratory space \| Gosselies, Belgium
Other Commitments [Line Items]
Land subject to leases \| m²		859		859
Contract Termination
Other Commitments [Line Items]
Restructuring charges				$ 0		$ 0
Minimum
Other Commitments [Line Items]
Contractual Agreement Cancelation Notice period				30 days
Average car lease duration		48 months		48 months
Maximum
Other Commitments [Line Items]
Contractual Agreement Cancelation Notice period				60 days
Average car lease duration		60 months		60 months