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Fair Value Measurements - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Estimated fair value of equity securities	$ 34,043		$ 34,043		$ 32,020
Unrealized gain on equity securities	694	$ 3,496	2,023	$ 323
Vaxcyte, Inc. | Vaxcyte Common Stock
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Estimated fair value of equity securities	34,000		34,000		$ 32,000
Unrealized gain on equity securities	$ 700	$ 3,500	$ 2,000	$ 300
Vaxcyte, Inc. | Equity Securities | Vaxcyte Common Stock
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Number of shares held	667,780		667,780		667,780
Fair Value Measurements Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held	$ 353,029		$ 353,029		$ 330,430

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