Fair Value of Financial Instruments - Quantitative Information and Assumptions Pertaining To The Fair Value Measurement of The Level 3 Inputs (Details) $ in Thousands	Sep. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)
Fair Value, Option, Quantitative Disclosures [Line Items]
Contingent receivable	$ 13,800	$ 11,300
Contingent consideration liabilities	46,800	15,800
Level 3
Fair Value, Option, Quantitative Disclosures [Line Items]
Contingent receivable	13,800	11,300
Contingent consideration liabilities	46,800	15,800
Level 3 | Regulatory milestone
Fair Value, Option, Quantitative Disclosures [Line Items]
Contingent receivable	3,300	3,200
Level 3 | Royalties
Fair Value, Option, Quantitative Disclosures [Line Items]
Contingent receivable	10,500	8,100
Level 3 | CVRs
Fair Value, Option, Quantitative Disclosures [Line Items]
Contingent consideration liabilities	33,200	4,200
Level 3 | 1095 commercialization milestone
Fair Value, Option, Quantitative Disclosures [Line Items]
Contingent consideration liabilities	1,900	2,200
Level 3 | Net sales targets - AZEDRA and 1095
Fair Value, Option, Quantitative Disclosures [Line Items]
Contingent consideration liabilities	$ 11,700	$ 9,400
Level 3 | Probability adjusted discounted cash flow model | Probability of success | Regulatory milestone
Fair Value, Option, Quantitative Disclosures [Line Items]
Asset measurement input	0.90	0.90
Level 3 | Probability adjusted discounted cash flow model | Probability of success | Royalties | Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Asset measurement input	0.13	0.13
Level 3 | Probability adjusted discounted cash flow model | Probability of success | Royalties | Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Asset measurement input	0.77	0.77
Level 3 | Probability adjusted discounted cash flow model | Probability of success | 1095 commercialization milestone
Fair Value, Option, Quantitative Disclosures [Line Items]
Liability measurement input	0.40	0.45
Level 3 | Probability adjusted discounted cash flow model | Discount rate | Regulatory milestone
Fair Value, Option, Quantitative Disclosures [Line Items]
Asset measurement input	0.18	0.24
Level 3 | Probability adjusted discounted cash flow model | Discount rate | Royalties
Fair Value, Option, Quantitative Disclosures [Line Items]
Asset measurement input	0.18	0.24
Level 3 | Probability adjusted discounted cash flow model | Discount rate | 1095 commercialization milestone
Fair Value, Option, Quantitative Disclosures [Line Items]
Liability measurement input	0.009	0.005
Level 3 | Monte Carlo simulation | Probability of success | Net sales targets - AZEDRA and 1095 | Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Liability measurement input	0.40	0.40
Level 3 | Monte Carlo simulation | Probability of success | Net sales targets - AZEDRA and 1095 | Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Liability measurement input	1	1
Level 3 | Monte Carlo simulation | Discount rate | CVRs
Fair Value, Option, Quantitative Disclosures [Line Items]
Liability measurement input	0.18	0.24
Level 3 | Monte Carlo simulation | Discount rate | Net sales targets - AZEDRA and 1095 | Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Liability measurement input	0.17	0.23
Level 3 | Monte Carlo simulation | Discount rate | Net sales targets - AZEDRA and 1095 | Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Liability measurement input	0.18	0.24