Liquidity (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands	Apr. 10, 2018	Jun. 30, 2019	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accumulated deficit		$ (391,229)	$ (342,864)
Cash and cash equivalents and short-term investments		$ 58,200
Public offering share value	3,418,918
Common stock, par value	$ 0.001	$ .001	$ .001
Public offering price per share	$ 8.51
Proceeds for public offering	$ 27,900

Cash and cash equivalents and short-term investments.

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Face amount or stated value per share of common stock.

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The cash inflow associated with the amount received from entity's first offering of stock to the public.

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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