Fair Value of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Fair Value of Financial Assets
Carrying amount of cash and cash equivalents and short term investments	$ 294,582	$ 333,288
Fair value of financial assets and liabilities
Marketable Securities	184,921	205,611
Derivative liability	1,290	1,340
Corporate Debt Securities and Commercial Paper
Fair value of financial assets and liabilities
Marketable Securities	184,921	205,611
Recurring \| Estimated fair value
Fair value of financial assets and liabilities
Fair value of assets	268,694	314,057
Derivative liability	1,290	1,340
Recurring \| Derivative on Royalty Financing \| Estimated fair value
Fair value of financial assets and liabilities
Derivative liability	1,290	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	184,921	205,611
Recurring \| Money Market Funds \| Estimated fair value
Fair value of financial assets and liabilities
Cash Equivalents	83,773	99,962
Recurring \| Level 1 \| Estimated fair value
Fair value of financial assets and liabilities
Fair value of assets	83,773	99,962
Recurring \| Level 1 \| Money Market Funds \| Estimated fair value
Fair value of financial assets and liabilities
Cash Equivalents	83,773	99,962
Recurring \| Level 2 \| Estimated fair value
Fair value of financial assets and liabilities
Fair value of assets	184,921	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	184,921	205,611
Recurring \| Level 3 \| Estimated fair value
Fair value of financial assets and liabilities
Derivative liability	1,290	1,340
Recurring \| Level 3 \| Derivative on Royalty Financing \| Estimated fair value
Fair value of financial assets and liabilities
Derivative liability	$ 1,290	$ 1,340

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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