Collaboration Profit and Loss - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Jul. 21, 2021	Jul. 01, 2021
Business Acquisition [Line Items]
Transaction price allocated under collaborative arrangement	$ 34,543		$ 34,543		$ 34,770
Collaboration (profit)/loss related to pre-launch activities	313	$ 1,051	5,158	$ 346
Topic 808 [Member] | Nestle Health Science [Member] | 2021 License Agreement [Member]
Business Acquisition [Line Items]
Transaction price allocated under collaborative arrangement						$ 35,500
Topic 808 [Member] | Total Liabilities [Member] | Nestle Health Science [Member] | 2021 License Agreement [Member]
Business Acquisition [Line Items]
Transaction price allocated under collaborative arrangement						$ 35,500	$ 35,500
Topic 808 [Member] | Accrued Expenses and Other Current Liabilities [Member] | Nestle Health Science [Member] | 2021 License Agreement [Member]
Business Acquisition [Line Items]
Transaction price allocated under collaborative arrangement	15,791		15,791		$ 34,770
Research and Development Expenses [Member] | Topic 808 [Member] | Nestle Health Science [Member] | 2021 License Agreement [Member]
Business Acquisition [Line Items]
Cost associated with pre-launch activities	0	1,182	1,446	4,355
General and Administrative Expenses [Member] | Topic 808 [Member] | Nestle Health Science [Member] | 2021 License Agreement [Member]
Business Acquisition [Line Items]
Cost associated with pre-launch activities	$ 0	$ 1,676	$ 4,242	$ 6,290