It represents the term of agreement.

No definition available.

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- Definition

Amount required to be remitted under the collaborative arrangement .

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Period within which the company is required to be remit the specified amount under the collaborative arrangement.

+ References

No definition available.

+ Details

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- Definition

The amortization of milestone payments.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

The amount of milestone payment made during the period under the license agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The amount of milestone payments payable under the license agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The percent of milestone payments reimbursable by deduction from deferred consideration.

+ References

No definition available.

+ Details

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Namespace Prefix:	iova_
Data Type:	dtr-types:percentItemType
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- Definition

The required notification period before the party may terminate the agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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- Definition

Number of historical asset purchase agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	iova_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of historical license agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	iova_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of historical master cell bank license and working cell bank transfer agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	iova_
Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

The number of suites under the agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	iova_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of expenses related to initiation of patient dosing, recorded during the period.

+ References

No definition available.

+ Details

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

- Definition

Represents the required quarterly payments under research and development agreement.

+ References

No definition available.

+ Details

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

- Definition

The amount of costs incurred under a research and development arrangement accounted for as a contract to perform research and development for others.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Balance Type:	debit
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- Definition

Amount of expense for research and development. Includes, but is not limited to, cost for computer software product to be sold, leased, or otherwise marketed and writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both. Excludes write-down of intangible asset acquired in business combination or from joint venture formation or both, used in research and development activity.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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-Publisher FASB
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Name:	us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis=iova_StrategicAllianceAgreementMember
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Name:	srt_RangeAxis=srt_MaximumMember
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LICENSES AND AGREEMENTS (Details) $ in Thousands		1 Months Ended					3 Months Ended		12 Months Ended
LICENSES AND AGREEMENTS (Details) $ in Thousands	May 18, 2023 USD ($) item	Jul. 31, 2024 USD ($)	Oct. 31, 2022 item	Apr. 30, 2017 USD ($)	Nov. 30, 2016 item	Aug. 31, 2011	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2020 USD ($)
Research and development							$ 76,879	$ 79,783
Through the end of 2024
Quarterly payment for research and development		$ 500
Commencing in 2025 and end of agreement term
Quarterly payment for research and development		$ 900
Strategic Alliance Agreement
Research and development							0	400
Research and development arrangement, contract to perform for others, costs incurred, gross				$ 5,300
Maximum \| Strategic Alliance Agreement
Research and development arrangement, contract to perform for others, costs incurred, gross				$ 14,200
Sponsored research agreement
Research and development							100	100
First WuXi Manufacturing and Services Agreement
Number Of Suites Under The Agreement \| item					2
Second WuXi Manufacturing and Services Agreement
Agreement term			3 years
Number Of Suites Under The Agreement \| item			2
Patent license agreement related to the development and manufacture of TIL therapies
Amount of collaborative arrangement required to be remitted							$ 1,500
Period of collaborative arrangement required to be remitted							60 days
License agreement							$ 200
Second Amended and Restated Patent License Agreement
Amount of collaborative arrangement required to be remitted							$ 6,000
Period of collaborative arrangement required to be remitted							60 days
Phase 2 Clinical Study in Melanoma
Amount of collaborative arrangement required to be remitted									$ 600
Period of collaborative arrangement required to be remitted									60 days
Cooperative Research and Development Agreement
Agreement term		5 years				5 years
Research and development							$ 900	500
Notification period to terminate agreement		60 days
WuXi Apptech, Inc - Manufacturing and Services Agreement
Research and development							8,400	5,500
Cellectis S.A
Research and development							100	100
Novartis Pharma AG and Related Entities - License Agreement
Research and development								0		$ 10,000
Patient dosing initiation expenses							2,500
Number of historical asset purchase agreement. \| item	2
Number of historical master cell bank license and working cell bank transfer agreement \| item	1
Number of historical license agreement \| item	1
Amount of milestone payment made during the period under the license agreement							$ 0	$ 0
Percent of milestone payments reimbursable	25.00%
Novartis Pharma AG and Related Entities - License Agreement \| Maximum \| UNITED STATES
Amount of milestone payments payable under the license agreement	$ 30,000
Novartis Pharma AG and Related Entities - License Agreement \| Maximum \| Non-US
Amount of milestone payments payable under the license agreement	$ 15,000