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Royalty Revenue

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Fair value price of a single share of a number of saleable stocks of a company

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upfront payment received

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License Agreements - Additional Information (Details) $ / shares in Units, € in Millions	1 Months Ended	3 Months Ended		6 Months Ended			12 Months Ended
	Jan. 31, 2020 USD ($) $ / shares shares	Jun. 30, 2023 USD ($) shares	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) shares	Jun. 30, 2023 EUR (€)	Jun. 30, 2022 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2012 Item	Dec. 31, 2022 USD ($) shares	Jan. 09, 2020 USD ($) $ / shares
Research And Development Arrangement Contract To Perform For Others [Line Items]
Number of common shares \| shares		46,726,794		46,726,794					43,498,617
Value of common stock		$ 5,000		$ 5,000					$ 4,000
Research and development expense recognized		20,581,000	$ 15,792,000	38,374,000		$ 28,377,000
License Agreement \| Antecip
Research And Development Arrangement Contract To Perform For Others [Line Items]
Accrued royalty payments		1,500,000		$ 1,500,000
Number of exclusive license agreements \| Item								3
License agreement royalty as a percent of net sales				3.00%	3.00%
License agreement royalty, maximum reduction percent as a result of required third party payments								50.00%
License agreement term, from first commercial sale								10 years
License Agreement \| Antecip \| AXS-02
Research And Development Arrangement Contract To Perform For Others [Line Items]
License agreement royalty as a percent of net sales								4.50%
License Agreement \| Antecip \| AXS-05
Research And Development Arrangement Contract To Perform For Others [Line Items]
License agreement royalty as a percent of net sales								3.00%
License Agreement \| Antecip \| AXS-04
Research And Development Arrangement Contract To Perform For Others [Line Items]
License agreement royalty as a percent of net sales								1.50%
Pfizer Inc \| License Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
Number of common shares \| shares	82,019
Value of common stock	$ 8,000,000.0
Prior trading days	10 days
Share price \| $ / shares	$ 97.54
Upfront cash payment	$ 3,000,000.0
Fair value share price \| $ / shares										$ 87.24
Fair value of common stock										$ 7,200,000
Research and development expense recognized							$ 10,200,000
Future milestone payments		323,000,000		$ 323,000,000
Milestone payments or royalties			$ 0	0		$ 0
Pharmanovia \| License Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
Non-refundable upfront payment received				65,700,000	€ 62.0
Eligible to receive sales-based and other milestones \| €					€ 94.5
Royalty revenue		$ 700,000		$ 1,000,000.0