Astellas Agreements - Summary of Allocation for Transaction Price to the Three Performance Obligations (Details) - Astellas - USD ($) $ in Thousands	1 Months Ended	9 Months Ended
	Oct. 31, 2022	Sep. 30, 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Transaction Price Allocation	$ 36,100	$ 36,059
Option to obtain license for Rett
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Transaction Price Allocation		5,485
Option to obtain license for GAN
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Transaction Price Allocation		2,317
Rett Research and Development Activities
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Transaction Price Allocation		$ 28,257