Stock-Based Compensation - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expense	$ 1,670	$ 797	$ 3,216	$ 2,369
Unrecognized stock-based compensation expense	5,900		$ 5,900
Unrecognized stock-based compensation expense expected to be recognized, term			1 year 6 months
Performance Stock Units (PSUs) \| Employees
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Granted			225,000
Total fair value of awards			$ 3,900
Stock-based compensation expense	$ 900		$ 900

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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ASSEMBLY BIOSCIENCES, INC. 10-Q