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Liquidity and Going Concern - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Liquidity [Abstract]
Net loss	$ 1,839	$ 1,087	$ 9,147	$ 3,150	$ 2,926	$ 12,297
Accumulated deficit	$ (428,196)				(428,196)		$ (425,270)
Net cash used in operating activities					$ (2,911)	$ (4,420)
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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Liquidity Abstract

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Description of principal conditions or events that raised substantial doubt about the ability to continue as a going concern.

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