Acquisitions (Details) $ / shares in Units, $ in Thousands, € in Millions									1 Months Ended				3 Months Ended				6 Months Ended		12 Months Ended
	Apr. 01, 2025 USD ($)	Jul. 03, 2024 USD ($)	Jul. 03, 2024 EUR (€)	Jul. 02, 2024 USD ($)	Jun. 18, 2024 USD ($)	Jun. 15, 2024 USD ($) LicensedAsset shares	Jun. 14, 2024	Jan. 08, 2024 USD ($)	May 31, 2025 USD ($)	Mar. 31, 2025 USD ($)	Jan. 31, 2025 USD ($) $ / shares shares	Aug. 31, 2024 USD ($)	Jun. 30, 2025 USD ($) $ / shares shares	Sep. 30, 2024 USD ($) $ / shares shares	Jun. 30, 2024 USD ($)	Mar. 31, 2024 USD ($)	Jun. 30, 2025 USD ($) $ / shares shares	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($) shares	Jan. 22, 2025 $ / shares shares	Mar. 06, 2024 $ / shares shares
Asset Acquisition [Line Items]
Business combination contingent consideration liability													$ 43,042				$ 43,042
Acquisition of exclusive license option																	0	$ 28,000
Research and development													$ 45,489		$ 60,601		$ 81,803	108,625
Radiopharm Theranostics Limited
Asset Acquisition [Line Items]
Shares owned (in shares) | shares											133,333,333		282,958,513	149,625,180			282,958,513		149,625,180
Percentage of shares outstanding																	12.00%
Share price (in dollars per share) | $ / shares											$ 0.04		$ 0.01	$ 0.03			$ 0.01
Purchase amount in investment in equity securities											$ 5,000			$ 5,000
Radiopharm Theranostics Limited | Maximum [Member]
Asset Acquisition [Line Items]
Equity Method Investment Shares Outstanding | $ / shares																	$ 20
Agreement with Perspective Therapeutics, Inc
Asset Acquisition [Line Items]
Disposal group consideration								$ 8,000
Perspective Therapeutics, Inc
Asset Acquisition [Line Items]
Subsidiary, ownership percentage, noncontrolling owner																					19.90%
Research and development																$ 28,000
Shares owned (in shares) | shares						11,677,339							11,677,339				11,677,339
Conversion ratio							0.1
Share price (in dollars per share) | $ / shares													$ 3.44				$ 3.44
Perspective Therapeutics, Inc | Licenses
Asset Acquisition [Line Items]
Acquisition of exclusive license option								$ 28,000
Perspective Therapeutics, Inc, Fully Diluted Basis
Asset Acquisition [Line Items]
Subsidiary, ownership percentage, noncontrolling owner																					17.35%
Perspective Common Stock
Asset Acquisition [Line Items]
Shares acquired (in shares) | shares																				56,342,355	60,431,039
Percentage of acquired interest																				11.39%
Share price (in dollars per share) | $ / shares																				$ 0.37	$ 0.95
Evergreen Theragnostics
Asset Acquisition [Line Items]
Payments to acquire businesses	$ 276,424
Business combination contingent consideration liability	25,000
Acquisition and integration related costs													$ 14,700				$ 17,200
Payment of transaction expenses	11,600
Nonrecurring post combination expense													7,500				7,500
Component of consideration transferred	6,100
Pre existing debt	4,300
Additional Milestone Payments | Evergreen Theragnostics
Asset Acquisition [Line Items]
Business combination contingent consideration liability	$ 727,500
Radiopharm Theranostics Limited
Asset Acquisition [Line Items]
Research and development																			$ 2,000
Payment for acquisitions						$ 2,000
Asset acquisition, additional milestone payments						$ 20,000
Number of licensed asset acquired | LicensedAsset						2
Radiopharm Theranostics Limited | Sales Milestones
Asset Acquisition [Line Items]
Asset acquisition, additional milestone payments						$ 6,500
Meilleur Technologies, Inc
Asset Acquisition [Line Items]
Payment for acquisitions					$ 32,900							$ 10,000
Asset acquisition, additional milestone payments					43,000
Meilleur Technologies, Inc | Research Revenue Milestones
Asset Acquisition [Line Items]
Asset acquisition, additional milestone payments					$ 4,000
Life Molecular Imaging, RM2 Technology
Asset Acquisition [Line Items]
Research and development													$ 0		$ 36,000		$ 5,400	$ 36,000
Payment for acquisitions		$ 35,000		$ 1,000
Life Molecular Imaging, RM2 Technology | Sales Milestones
Asset Acquisition [Line Items]
Asset acquisition, additional milestone payments | €			€ 280.0
Life Molecular Imaging, RM2 Technology | Regulatory Milestones
Asset Acquisition [Line Items]
Payment for acquisitions										$ 5,400
Asset acquisition, additional milestone payments | €			€ 77.5
AstraZeneca
Asset Acquisition [Line Items]
Non-refundable upfront payment to adjust the future royalty obligations									$ 10,000