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Transactions with BioXcel LLC (Details) - USD ($) $ in Thousands		3 Months Ended
	Jun. 30, 2017	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Transactions with BioXcel
Research and development		$ 11,401	$ 27,800
Selling, general and administrative		13,264	23,595
Total operating expenses		24,745	51,404
BioXcel LLC
Transactions with BioXcel
Monthly agreement option fees	$ 18
Maximum milestone (as as percent)	3.00%
BioXcel LLC \| Development milestones
Transactions with BioXcel
Potential milestone payments	$ 10,000
BioXcel LLC \| Sales milestones
Transactions with BioXcel
Potential milestone payments	$ 30,000
Related Party
Transactions with BioXcel
Other current liabilities		116		$ 107
Related Party \| BioXcel LLC
Transactions with BioXcel
Research and development		186	215
Selling, general and administrative		48	26
Total operating expenses		234	$ 241
Other current liabilities		$ 0