Fair Value of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Fair Value of Financial Assets
Carrying amount of cash and cash equivalents and short term investments	$ 201,199	$ 275,846
Fair value of financial assets and liabilities
Marketable Securities	147,771	215,765
Derivative liability	660	1,150
Corporate Debt Securities and Commercial Paper
Fair value of financial assets and liabilities
Marketable Securities	147,771	215,765
Recurring \| Estimated fair value
Fair value of financial assets and liabilities
Fair value of assets	190,799	261,612
Derivative liability	660	1,150
Recurring \| Derivative on Royalty Financing \| Estimated fair value
Fair value of financial assets and liabilities
Derivative liability	660	1,150
Recurring \| Corporate Debt Securities and Commercial Paper \| Estimated fair value
Fair value of financial assets and liabilities
Marketable Securities	147,771	215,765
Recurring \| Money Market Funds \| Estimated fair value
Fair value of financial assets and liabilities
Cash Equivalents	43,028	45,847
Recurring \| Level 1 \| Estimated fair value
Fair value of financial assets and liabilities
Fair value of assets	43,028	40,868
Recurring \| Level 1 \| Money Market Funds \| Estimated fair value
Fair value of financial assets and liabilities
Cash Equivalents	43,028	40,868
Recurring \| Level 2 \| Estimated fair value
Fair value of financial assets and liabilities
Fair value of assets	147,771	220,744
Recurring \| Level 2 \| Corporate Debt Securities and Commercial Paper \| Estimated fair value
Fair value of financial assets and liabilities
Marketable Securities	147,771	215,765
Recurring \| Level 2 \| Money Market Funds \| Estimated fair value
Fair value of financial assets and liabilities
Cash Equivalents		4,979
Recurring \| Level 3 \| Estimated fair value
Fair value of financial assets and liabilities
Derivative liability	660	1,150
Recurring \| Level 3 \| Derivative on Royalty Financing \| Estimated fair value
Fair value of financial assets and liabilities
Derivative liability	$ 660	$ 1,150

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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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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