v3.25.4

Stock-Based Compensation - Schedule of Common Stock Option Activity (Detail) - 2018 Stock Option and Incentive Plan and Inducement Plan [Member] $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2025 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options Outstanding, Beginning balance \| shares	21,497,158
Number of Options, Granted \| shares	7,538,879
Number of Options, Exercised \| shares	(1,327,446)
Number of Options, Forfeited \| shares	(349,024)
Number of Options Outstanding, Ending balance \| shares	27,359,567
Number of Options, Vested and expected to vest \| shares	27,358,567
Number of Options, Exercisable \| shares	16,783,067
Weighted Average Exercise Price, Outstanding, Beginning balance \| $ / shares	$ 8.83
Weighted Average Exercise Price, Granted \| $ / shares	12.67
Weighted Average Exercise Price, Exercised \| $ / shares	8.7
Weighted Average Exercise Price, Forfeited \| $ / shares	8.89
Weighted Average Exercise Price, Outstanding, Ending balance \| $ / shares	9.9
Weighted Average Exercise Price, Vested and expected to vest \| $ / shares	9.9
Weighted Average Exercise Price, Exercisable \| $ / shares	$ 9.13
Weighted Average Contractual Term, Outstanding, Ending balance	7 years 2 months 15 days
Weighted Average Contractual Term, Vested and expected to vest	7 years 2 months 15 days
Weighted Average Contractual Term, Exercisable	6 years 3 months
Aggregate Intrinsic Value, Outstanding \| $	$ 747,167
Aggregate Intrinsic Value, Vested and expected to vest \| $	747,167
Aggregate Intrinsic Value, Exercisable \| $	$ 469,808

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Cogent Biosciences, Inc. 10-K