v3.25.4

Leases (Details) $ in Millions	1 Months Ended	12 Months Ended
Leases (Details) $ in Millions	Sep. 30, 2025 ft² item	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Leases
Lessee, Operating Lease, Existence of Option to Extend [true false]		true
Increase in right of use assets for new leases and lease extensions		$ 0.1	$ 2.9	$ 0.1
Increase in lease liabilities for new lease and lease extensions		0.1	2.9	0.1
Operating lease expense		2.1	2.0	1.9
Variable lease expense		0.9	0.8	0.8
Operating lease payments		$ 2.1	$ 2.0	$ 2.0
Weighted-average remaining lease term		1 year	2 years
Weighted-average discount rate		10.00%	10.00%
Area of lease space \| ft²	40,400
Initial lease term	5 years 6 months
Number of renewal options available \| item	3
Lease renewal term	5 years
Purchase obligations		$ 4.5
Unrecorded Unconditional Purchase Obligation, Category [Extensible Enumeration]		us-gaap:OperatingLeaseLeaseNotYetCommencedMember
Minimum
Leases
Remaining lease term (in years)		1 year
Maximum
Leases
Remaining lease term (in years)		5 years

The area of lease space, entered in a lease agreement.

+ References

No definition available.

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- Definition

Number of renewal options available to the lessee under operating lease arrangements that had been executed but had not yet commenced as of the reporting date.

+ References

No definition available.

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- Definition

Amount of increase in operating lease liabilities for new leases and lease extensions.

+ References

No definition available.

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- Definition

Amount of increase in operating lease, right of use assets for new leases and lease extensions.

+ References

No definition available.

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- 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.

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- Definition

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

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- Definition

Term of lessee's operating lease renewal for lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Term of lessee's operating lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

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

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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- Definition

Weighted average discount rate for operating lease calculated at point in time.

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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of unrecorded obligation to transfer funds in future for fixed or minimum amount or quantity of product and service at fixed or minimum price. Includes, but is not limited to, lease not yet commenced and take-or-pay and throughput contracts.

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- Definition

Indicates category of product and service for unrecorded unconditional purchase arrangement to acquire product or service.

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- Definition

Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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Celldex Therapeutics, Inc. 10-K