Prepaid Expenses, Other Current Assets and Other Noncurrent Assets - Summary of Prepaid Expenses and Other Noncurrent Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Prepaid Expense and Other Assets, Noncurrent [Abstract]
Deferred transaction costs	$ 0	$ 3,912
Prepaid external research and development - long term	35	676
Other	5	23
Total other noncurrent assets	$ 40	$ 4,611