Investments and Other Assets - Schedule of Investments and Other Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023
Investments, All Other Investments [Abstract]
Investment in Kyverna Therapeutics, Inc.	$ 5,740	$ 10,000
Other investments	24,213	14,760
Restricted cash equivalents, long-term	13,605	13,605	$ 12,957
Prepaid expenses and other assets, long-term	3,230	4,518
Total investments and other assets	$ 46,788	$ 42,883

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Amount of investments, and noncurrent assets classified as other.

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Fair value portion of investments in an entity not consolidated. Includes, but is not limited to, investments in an entity that is affiliated with the reporting entity by means of direct or indirect ownership, an entity in which the reporting entity shares control of the entity with another party or group, an entity which the company has significant influence, but does not have control and subsidiaries that are not required to be consolidated and are accounted for using the equity or cost method.

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Amount of investments classified as other.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed after one year or the normal operating cycle, if longer.

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Amount of cash equivalents restricted as to withdrawal or usage. Cash equivalents include, but are not limited to, 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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