Fair Value Measurements - Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financial assets:
Marketable securities	$ 501,111	$ 544,787
Marketable equity securities	1,535
Total financial assets	502,646	544,787
Financial liabilities:
Success payment liabilities	2,544	1,576
Total financial liabilities	2,544	1,576
U.S. Treasury securities
Financial assets:
Marketable securities	343,194	374,356
U.S. government agency securities
Financial assets:
Marketable securities	38,427	48,750
Corporate debt securities
Financial assets:
Marketable securities	68,682	59,606
Money market funds
Financial assets:
Money market funds	50,808	62,075
Level 1
Financial assets:
Marketable equity securities	1,535
Total financial assets	52,343	62,075
Financial liabilities:
Success payment liabilities	0	0
Total financial liabilities	0	0
Level 1 \| U.S. Treasury securities
Financial assets:
Marketable securities	0	0
Level 1 \| U.S. government agency securities
Financial assets:
Marketable securities	0	0
Level 1 \| Corporate debt securities
Financial assets:
Marketable securities	0	0
Level 1 \| Money market funds
Financial assets:
Money market funds	50,808	62,075
Level 2
Financial assets:
Marketable equity securities	0
Total financial assets	450,303	482,712
Financial liabilities:
Success payment liabilities	0	0
Total financial liabilities	0	0
Level 2 \| U.S. Treasury securities
Financial assets:
Marketable securities	343,194	374,356
Level 2 \| U.S. government agency securities
Financial assets:
Marketable securities	38,427	48,750
Level 2 \| Corporate debt securities
Financial assets:
Marketable securities	68,682	59,606
Level 2 \| Money market funds
Financial assets:
Money market funds	0	0
Level 3
Financial assets:
Marketable equity securities	0
Total financial assets	0	0
Financial liabilities:
Success payment liabilities	2,544	1,576
Total financial liabilities	2,544	1,576
Level 3 \| U.S. Treasury securities
Financial assets:
Marketable securities	0	0
Level 3 \| U.S. government agency securities
Financial assets:
Marketable securities	0	0
Level 3 \| Corporate debt securities
Financial assets:
Marketable securities	0	0
Level 3 \| Money market funds
Financial assets:
Money market funds	$ 0	$ 0

Success Payment Liabilities, Fair Value Disclosure

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
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-Topic 320
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-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481830/320-10-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

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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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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(1)(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 1
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-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482736/825-10-45-1A

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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