Organization and Description of Business - Liquidity (Details) $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($) segment	Dec. 31, 2019 USD ($)
Organization and Description of Business
Number of operating segments \| segment	1
Net losses from operations since inception
Accumulated deficit \| $	$ (257,162)	$ (217,661)

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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