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License Agreements - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2022	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Dec. 31, 2021	Jan. 31, 2022	Jun. 30, 2020
License Agreements [Line Items]
Common Stock, Value, Issued	$ 18,571		$ 300				$ 18,571	$ 300	$ 18,562
ATAI Kures Inc. [Member] \| License Agreement Terms [Member]
License Agreements [Line Items]
Percentage of the common stock shares outstanding												5.00%
Research And Development Services [Member] \| License Agreement Terms [Member]
License Agreements [Line Items]
process research And development expense			400					400
Otsuka Agreement [Member]
License Agreements [Line Items]
Revenue Related To Certain Research And Development	100		100				300	200
Columbia Stock Purchase and License Agreement [Member]
License Agreements [Line Items]
Material Payment	0		0				0	0
Accelerate License Agreement [Member]
License Agreements [Line Items]
Material Payment		$ 0		$ 0	$ 0	$ 0
CHIBA License [Member]
License Agreements [Line Items]
Material Payment	0		0				0	0
Allergan License Agreement [Member]
License Agreements [Line Items]
Material Payment	0		0				0	0
Dalriada License Agreement [Member]
License Agreements [Line Items]
Service fees	0		0				0	0		$ 12,800
Dalriada License Agreement [Member] \| Research And Development Services [Member]
License Agreements [Line Items]
process research And development expense	400		$ 1,000				1,500	$ 2,800	600
Invyxis ESLA [Member]
License Agreements [Line Items]
Upfront deposit											$ 1,100
Invyxis ESLA [Member] \| Minimum [Member]
License Agreements [Line Items]
Upfront deposit									500
Invyxis ESLA [Member] \| Maximum [Member]
License Agreements [Line Items]
Upfront deposit									$ 1,100
Otsuka [Member] \| Otsuka Agreement [Member]
License Agreements [Line Items]
Performance obligation										$ 20,000
Otsuka [Member] \| Commercial Milestones [Member] \| Otsuka Agreement [Member]
License Agreements [Line Items]
Milestone payments, receivable	66,000						66,000
Otsuka [Member] \| Development And Regulatory Milestones [Member] \| Otsuka Agreement [Member]
License Agreements [Line Items]
Milestone payments, receivable	$ 35,000						$ 35,000