v3.20.2

Additional paid in capital - Fair Value Method Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Fair Value Method Stock-Based Compensation [Abstract]
Risk-free interest rate	0.38%	1.84%	2.52%	2.34%
Expected life	4 years 10 months 25 days	5 years	5 years	5 years
Expected dividends	$ 0	$ 0	$ 0	$ 0
Expected volatility	320.00%	306.00%	309.00%	330.00%
Forfeiture rate	$ 0	$ 0	$ 0	$ 0

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- References

No definition available.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Disclosure of the weighted average expected dividend for an entity using a valuation technique with different dividend rates during the contractual term.

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- Definition

The combined weighted average of the accumulated differences between the fair values on underlying shares and exercises prices to acquire such shares as of the grant date on options that were either forfeited or lapsed.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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