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Stock-Based Compensation - Schedule of Total Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Employee Service Share Based Compensation Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 9,566	$ 13,100	$ 27,803	$ 35,617
Stock-based compensation		13,100	27,803	35,617
Aeglea Employees and Directors
Employee Service Share Based Compensation Allocation of Recognized Period Costs [Line Items]
Stock-based compensation		100		3,600
Parapyre Option Obligation
Employee Service Share Based Compensation Allocation of Recognized Period Costs [Line Items]
Stock-based compensation		6,100		13,000
Research and development
Employee Service Share Based Compensation Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	4,248	8,555	11,860	18,863
General and administrative
Employee Service Share Based Compensation Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 5,318	$ 4,545	$ 15,943	$ 16,754