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Liquidity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended				6 Months Ended
	May 24, 2022	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Liquidity [Abstract]
Net loss		$ (5,282)	$ (4,116)	$ (2,800)	$ (2,720)	$ (9,398)	$ (5,520)
Accumulated deficit		$ (456,308)				(456,308)		$ (446,910)
Net cash used in operating activities						$ (6,516)	$ (5,405)
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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