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Liability Related to Sale of Future Revenues - Additional Information (Details) - USD ($) |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
Nov. 04, 2022 | Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Total revenue |  | $ 44,319,000 | $ 29,806,000 | $ 80,480,000 | $ 90,633,000
NovaQuest Capital Management [Member] | Revenue Interest Financing Agreement [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Effective annual interest rate related to sale of future revenues |  | 15.95% |  | 15.95% |
NovaQuest Capital Management [Member] | Revenue Interest Financing Agreement [Member] | Minimum [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Prepayment amount of 2024 to 2030 | $ 80,000,000.0 |  |  |  |
NovaQuest Capital Management [Member] | Revenue Interest Financing Agreement [Member] | Maximum [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Prepayment amount of 2024 to 2030 | 125,000,000.0 |  |  |  |
NovaQuest Capital Management [Member] | Payment Period One [Member] | Revenue Interest Financing Agreement [Member] | Minimum [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Revenue interest payment | 62,500,000 |  |  |  |
NovaQuest Capital Management [Member] | Payment Cap Date on or before December 31, 2028 [Member] | Revenue Interest Financing Agreement [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Maximum payment cap amount | 100,000,000.0 |  |  |  |
NovaQuest Capital Management [Member] | Payment Cap Date on or after January 1, 2029 [Member] | Revenue Interest Financing Agreement [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Maximum payment cap amount | 112,500,000 |  |  |  |
NovaQuest Capital Management [Member] | Payment Cap Date after January 1, 2030 [Member] | Revenue Interest Financing Agreement [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Maximum payment cap amount | 125,000,000.0 |  |  |  |
NovaQuest Capital Management [Member] | Payment Period Two [Member] | Revenue Interest Financing Agreement [Member] | Minimum [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Revenue interest payment | 125,000,000.0 |  |  |  |
Product [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Total revenue |  | $ 23,889,000 | 23,256,000 | $ 48,049,000 | 42,137,000
Product [Member] | NovaQuest Capital Management [Member] | Revenue Interest Financing Agreement [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Revenue interest payment | 10,000,000.0 |  |  |  |
License [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Total revenue |  | 1,000,000 | 0 | 7,000,000 | 22,590,000
Other Revenue - Contract Manufacturing [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Total revenue |  | 5,158,000 | 5,457,000 | 9,050,000 | 17,219,000
Astellas Agreement [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Future revenue granted | $ 50,000,000.0 |  |  |  |
Percentage of revenue interest on global net sales | 100.00% |  |  |  |
Astellas Agreement [Member] | Maximum [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Revenue payment cap amount |  | 125,000,000.0 |  | 125,000,000.0 |
Astellas Agreement [Member] | Product [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Percentage of revenue sold | 22.50% |  |  |  |
Astellas Agreement [Member] | Milestone payments [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Percentage of revenue sold | 10.00% |  |  |  |
Astellas Agreement [Member] | Milestone payments [Member] | Payment Period One [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Percentage of revenue sold | 20.00% |  |  |  |
Development Revenue [Member] | Astellas Agreement [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Total revenue |  | 1,800,000 |  | 3,500,000 |
Drug Product Revenue [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Total revenue |  | 14,272,000 | $ 1,093,000 | 16,381,000 | $ 8,687,000
Drug Product Revenue [Member] | Astellas Agreement [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Total revenue |  | 14,300,000 |  | 16,400,000 |
Non-cash interest expense related to drug product revenue |  | $ 1,300,000 |  | $ 3,600,000 |

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