Investment Securities and Fair Value Measurements - Summary of Amortized Cost, Fair Value, and Unrealized Losses by Type of Security (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	$ 381,869	$ 512,466
Gross unrealized gains	534	795
Gross unrealized losses	(179)	(390)
Fair value	382,224	512,871
U.S. Government Agency Bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	52,912	47,959
Gross unrealized gains	57	91
Gross unrealized losses	(29)	(56)
Fair value	52,940	47,994
U.S. Treasury Bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	309,125	374,883
Gross unrealized gains	450	585
Gross unrealized losses	(150)	(330)
Fair value	309,425	375,138
Corporate Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	19,832	89,624
Gross unrealized gains	27	119
Gross unrealized losses	0	(4)
Fair value	$ 19,859	$ 89,739

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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iTeos Therapeutics, Inc. 10-Q