Name:	iova_AccountingPoliciesLineItems
Namespace Prefix:	iova_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The payment term of customers.

No definition available.

Name:	iova_CustomerPaymentTerm
Namespace Prefix:	iova_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Amount of impairment of investment in debt security, measured at amortized cost (held-to-maturity), charged against allowance for credit loss.

No definition available.

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

The amount of decrease in letters of credit on lease expiration.

No definition available.

Name:	iova_DecreaseInLettersOfCreditOnLeaseExpiration
Namespace Prefix:	iova_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Amount of minimum restricted security deposit to be maintained.

No definition available.

Name:	iova_MinimumRestrictedSecurityDeposit
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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Name:	us-gaap_CashAndCashEquivalentsAtCarryingValue
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Amount of cash and cash equivalent, and cash and cash equivalent restricted to withdrawal or usage; attributable to continuing operation. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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-Topic 230
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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
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Period Type:	instant

The amount of an asset, typically cash, provided to a counterparty to provide certain assurance of performance by the entity pursuant to the terms of a written or oral agreement, such as a lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
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-Name Accounting Standards Codification
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