Fair Value Measurements - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Write off of accrued interest receivable	$ 0	$ 0
Total net unrealized gain (loss) recorded in accumulated other comprehensive income (loss)	(500)		$ 900
Brii Bio Parent
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investment owned at fair value	3,900
Unrealized loss	(5,900)	$ (13,100)
Humabs
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Estimated fair value of contingent consideration	$ 27,600		26,000
Maximum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities contractual term	2 years
Prepaid Expenses and Other Current Assets
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Accrued interest receivable excluded from fair value and amortized cost basis of available for sale securities	$ 5,700		$ 4,000