Stock-Based Compensation - Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Stock-Based Compensation
Available for grant (in shares)	331,607
Share-based compensation costs recognized	$ 3,142	$ 3,082
Remaining unamortized expense	$ 2,772
Remaining unamortized expense period	1 year 3 months 18 days
Research and development expense
Stock-Based Compensation
Share-based compensation costs recognized	$ 1,791	1,843
General and administrative expense
Stock-Based Compensation
Share-based compensation costs recognized	$ 1,351	1,239
Options
Stock-Based Compensation
Number of options granted (in shares)	384,800
Share-based compensation costs recognized	$ 3,070	2,872
Options \| BioXcel Corporation
Stock-Based Compensation
Share-based compensation costs recognized	$ 72	$ 210

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Gross number of share options (or share units) granted during the period.

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