Estimated hazardous waste removal liability.

No definition available.

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Balance Type:	credit
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- Definition

Estimated reduction of reserve from hazardous haste disposal vendor.

+ References

No definition available.

+ Details

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- Definition

Lessee operating lease number of renewal options.

+ References

No definition available.

+ Details

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

- Definition

Amount of excess of rental payment required by lease over rental income recognized.

+ References

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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.

+ References

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

- Definition

Discount rate used by lessee to determine present value of operating lease payments.

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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

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- Definition

Amount of operating lease expense. Excludes sublease income.

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- Definition

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

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Balance Type:	credit
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- Definition

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

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Balance Type:	debit
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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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Period Type:	instant

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- Details

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Balance Type:
Period Type:

- Details

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Balance Type:
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- Details

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Note 12 - Leases (Details Textual) $ in Thousands		3 Months Ended		6 Months Ended
Note 12 - Leases (Details Textual) $ in Thousands	Aug. 08, 2024 USD ($) RenewalOption	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)	Apr. 01, 2024 USD ($)	Mar. 01, 2024 USD ($)	Jul. 01, 2023 USD ($)
Lessee, Lease, Description [Line Items]
Lease liability		$ 1,918		$ 1,918
Right of use asset		$ 1,767		$ 1,767		$ 2,215
Lease term	52 months
Operating lease, weighted average remaining term		2 years 9 months 18 days		2 years 9 months 18 days
Operating lease, weighted average discount rate		8.00%		8.00%
Operating lease, expense		$ 300	$ 200	$ 600	$ 300
Estimated reduction of reserve from hazardous waste disposal vendor		300		300
Estimated hazardous waste removal liability		$ 500		$ 500		$ 200
Lantheus Alpha Therapy, LLC [Member]
Lessee, Lease, Description [Line Items]
Number of renewal options \| RenewalOption	0
Maximum [Member] \| Lantheus Alpha Therapy, LLC [Member]
Lessee, Lease, Description [Line Items]
Base prepaid rent	$ 100
Office Space With Unico Properties [Member]
Lessee, Lease, Description [Line Items]
Lease liability									$ 800
Right of use asset									$ 800
Lessee, operating lease, discount rate									8.00%
Lease with Board of Regents [Member]
Lessee, Lease, Description [Line Items]
Lease liability							$ 1,100
Right of use asset							$ 1,100
Lessee, operating lease, discount rate							8.00%
Progenics [Member]
Lessee, Lease, Description [Line Items]
Lease liability	600							$ 300
Right of use asset	$ 600							$ 300
Lessee, operating lease, discount rate	8.00%							8.00%