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Liquidity and Going Concern - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Liquidity [Abstract]
Net loss	$ 1,728	$ 1,839	$ 1,087	$ (526)	$ 9,147	$ 3,150	$ 4,654	$ 11,771
Accumulated deficit	$ (429,924)						(429,924)		$ (425,270)
Net cash used in operating activities							$ (5,210)	$ (6,942)
Substantial doubt about going concern, description							These factors raise substantial doubt about the Company’s ability to continue as a going concern

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