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Significant Accounting Policies - Estimated Fair Value of Assets and Liability (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Asset:
Asset, fair value	$ 232,240	$ 192,307
Money Market Fund
Asset:
Asset, fair value	179,173	81,870
Commercial Paper
Asset:
Asset, fair value	4,769	62,347
Agency Securities
Asset:
Asset, fair value	18,762	1,554
Certificates of Deposit
Asset:
Asset, fair value	1,600	9,100
Corporate Bonds
Asset:
Asset, fair value		28,416
Repo Securities
Asset:
Asset, fair value	3,250	3,250
U.S. Treasury Securities
Asset:
Asset, fair value	24,686	3,117
Asset Backed Securities
Asset:
Asset, fair value		1,260
Non-US Government
Asset:
Asset, fair value		1,393
Level 1
Asset:
Asset, fair value	203,859	86,541
Level 1 | Money Market Fund
Asset:
Asset, fair value	179,173	81,870
Level 1 | Agency Securities
Asset:
Asset, fair value		1,554
Level 1 | U.S. Treasury Securities
Asset:
Asset, fair value	24,686	3,117
Level 2
Asset:
Asset, fair value	28,381	105,766
Level 2 | Commercial Paper
Asset:
Asset, fair value	4,769	62,347
Level 2 | Agency Securities
Asset:
Asset, fair value	18,762
Level 2 | Certificates of Deposit
Asset:
Asset, fair value	1,600	9,100
Level 2 | Corporate Bonds
Asset:
Asset, fair value		28,416
Level 2 | Repo Securities
Asset:
Asset, fair value	$ 3,250	3,250
Level 2 | Asset Backed Securities
Asset:
Asset, fair value		1,260
Level 2 | Non-US Government
Asset:
Asset, fair value		$ 1,393

X

- 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
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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