Stock-Based Compensation - Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Employee Service Share Based Compensation Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 13,100	$ 4,785	$ 35,617	$ 8,405
Stock-based compensation	13,100	4,800	35,617	8,405
Aeglea Employees and Directors
Employee Service Share Based Compensation Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	100	800	3,600	4,200
Parapyre Option Obligation
Employee Service Share Based Compensation Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	6,100	2,700	13,000	2,900
Research and Development Expense
Employee Service Share Based Compensation Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	8,555	2,965	18,863	4,136
General and administrative
Employee Service Share Based Compensation Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 4,545	$ 1,820	$ 16,754	$ 4,269