Fair Value of Financial Instruments - Narrative (Details)	3 Months Ended
Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)
Fair Value, Option, Quantitative Disclosures [Line Items]
Company acquired right to receive certain future milestone	$ 92,509,000	$ 90,704,000
Progenics Pharmaceuticals Inc
Fair Value, Option, Quantitative Disclosures [Line Items]
Royalty percentage	0.05
Potential payments, high	$ 85,000,000.0
Progenics Pharmaceuticals Inc \| Net Sales Targets For Azedra
Fair Value, Option, Quantitative Disclosures [Line Items]
Potential payments, high	70,000,000.0
Progenics Pharmaceuticals Inc \| 1095 commercialization milestone
Fair Value, Option, Quantitative Disclosures [Line Items]
Potential payments, high	5,000,000.0
Progenics Pharmaceuticals Inc \| 1404 Commercialization Milestone
Fair Value, Option, Quantitative Disclosures [Line Items]
Business Combination, Contingent Consideration Arrangements, Range Of Outcomes Not Reasonably Possible, Value	10,000,000.0
Royalty \| Progenics Pharmaceuticals Inc
Fair Value, Option, Quantitative Disclosures [Line Items]
Company acquired right to receive certain future milestone	$ 5,000,000.0

Business Combination, Contingent Consideration Arrangements, Range Of Outcomes Not Reasonably Possible, Value

No definition available.

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- Definition

Royalty Percentage

+ References

No definition available.

+ Details

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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ 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

No definition available.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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