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Liquidity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended						9 Months Ended
	May 24, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Liquidity [Abstract]
Net loss		$ (5,219)	$ (5,282)	$ (4,116)	$ (3,724)	$ (2,800)	$ (2,720)	$ (14,617)	$ (9,244)
Accumulated deficit		$ (461,527)						(461,527)		$ (446,910)
Net cash used in operating activities								$ (10,738)	$ (7,656)
Closing bid price for common stock had fallen below	$ 1.00
Consecutive business days	30 days							10 days
Closing bid price		$ 1.00						$ 1.00
Period for regain compliance								180 days

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