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Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
	Mar. 29, 2022	Mar. 31, 2022	Mar. 31, 2021	Jan. 01, 2022	Dec. 31, 2021
Stock option and incentive plans
Total compensation cost		$ 3,078	$ 4,980
Shares
Number of common shares issued for each convertible Series A preferred stock		915,000
Ovid License Agreement
Stock option and incentive plans
Stock Issued During Period, Shares, New Issues	123,255
Series A Preferred Stock
Shares
Preferred stock, shares outstanding		4,575			4,575
Common Stock
Stock option and incentive plans
Stock Issued During Period, Shares, New Issues		123,255
Stock option
Stock Options
Outstanding (in shares)		5,654,024
Outstanding, weighted-average exercise price (in dollars per share)		$ 11.66
Granted (in shares)		1,341,399
Granted (in dollars per share)		$ 10.47
Restricted stock awards and RSUs
Stock option and incentive plans
Total compensation cost		$ 301	55
Stock Options
Outstanding (in shares)		22,625
Shares
Issued (in shares)		515,645
Outstanding (in shares)		519,045
Restricted stock awards and RSUs \| Research and development.
Stock option and incentive plans
Total compensation cost		$ 99
Restricted stock awards and RSUs \| General and administrative
Stock option and incentive plans
Total compensation cost		$ 202	55
2005 Plan
Stock option and incentive plans
Common stock reserved for issuance (in shares)		0
2005 Plan \| Stock option
Stock Options
Outstanding (in shares)		577
2014 Plan
Stock option and incentive plans
Common stock reserved for issuance (in shares)		816,377		2,343,330
2014 Plan \| Research and development.
Stock option and incentive plans
Total compensation cost		$ 1,179	1,190
2014 Plan \| General and administrative
Stock option and incentive plans
Total compensation cost		$ 1,899	$ 3,790
2014 Plan \| Stock option
Stock Options
Outstanding (in shares)		4,072,818
Granted (in shares)		1,204,388
Equity Incentive Plan, Employee Inducements \| Stock option
Stock Options
Outstanding (in shares)		1,580,629
Granted (in shares)		137,011