v3.25.0.1

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2020
Income Tax Contingency [Line Items]
Effective tax rate	(11.70%)	(3.30%)
Effective income tax rate reconciliation, at federal statutory income tax rate, percent	21.00%	21.00%
Increase in valuation allowance	$ 22,900
Deferred tax assets valuation allowance	97,331	$ 74,398
Net operating loss Carry forwards deductible at maximum rate of corporations taxable income			80.00%
Foreign	(40,789)	(38,858)
Federal NOL carryforwards	0
Unrecognized tax benefits	46,720	40,930
Income tax expense benefit	14,072	3,612
Unrecognized tax benefits income tax interest accrued	4,300	1,700
Increase in unrecognized tax benefits		0
Accrued interest
Income Tax Contingency [Line Items]
Unrecognized tax benefits income tax interest accrued	$ 8,300	$ 3,900
Federal
Income Tax Contingency [Line Items]
Operating loss carryforwards expiration year	2043
State
Income Tax Contingency [Line Items]
Operating loss carryforwards expiration year	2043
Gosselies, Belgium
Income Tax Contingency [Line Items]
Foreign	$ 61,900
Cambridge, Massachusetts
Income Tax Contingency [Line Items]
Federal NOL carryforwards	$ 35,900

Net operating loss Carry forwards deductible at Maximum Rate of corporations taxable income.

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iTeos Therapeutics, Inc. 10-K