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Fair Value of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Fair Value of Financial Assets
Carrying amount of cash and cash equivalents and short term investments	$ 299,260	$ 333,288
Fair value of financial assets and liabilities
Marketable Securities	234,668	205,611
Derivative liability	1,190	1,340
Corporate Debt Securities and Commercial Paper
Fair value of financial assets and liabilities
Marketable Securities	234,668	205,611
Recurring | Estimated fair value
Fair value of financial assets and liabilities
Fair value of assets	287,333	314,057
Derivative liability	1,190	1,340
Recurring | Derivative on Royalty Financing | Estimated fair value
Fair value of financial assets and liabilities
Derivative liability	1,190	1,340
Recurring | Commercial Paper | Estimated fair value
Fair value of financial assets and liabilities
Cash Equivalents		8,484
Recurring | Corporate Debt Securities and Commercial Paper | Estimated fair value
Fair value of financial assets and liabilities
Marketable Securities	234,667	205,611
Recurring | Money Market Funds | Estimated fair value
Fair value of financial assets and liabilities
Cash Equivalents	52,666	99,962
Recurring | Level 1 | Estimated fair value
Fair value of financial assets and liabilities
Fair value of assets	52,666	99,962
Recurring | Level 1 | Money Market Funds | Estimated fair value
Fair value of financial assets and liabilities
Cash Equivalents	52,666	99,962
Recurring | Level 2 | Estimated fair value
Fair value of financial assets and liabilities
Fair value of assets	234,667	214,095
Recurring | Level 2 | Commercial Paper | Estimated fair value
Fair value of financial assets and liabilities
Cash Equivalents		8,484
Recurring | Level 2 | Corporate Debt Securities and Commercial Paper | Estimated fair value
Fair value of financial assets and liabilities
Marketable Securities	234,667	205,611
Recurring | Level 3 | Estimated fair value
Fair value of financial assets and liabilities
Derivative liability	1,190	1,340
Recurring | Level 3 | Derivative on Royalty Financing | Estimated fair value
Fair value of financial assets and liabilities
Derivative liability	$ 1,190	$ 1,340

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