Equity - Stock Options - Valuation assumptions (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Share-based compensation
Granted (in shares)	1,328,718	224,000
Exercise price (in dollars per share)	$ 1.32	$ 1.94
Expected life	5 years 9 months	6 years 2 months 12 days
Weighted average volatility	71.00%	70.00%
Forfeiture rate	20.00%	15.00%
Weighted average risk-free interest rate	2.52%	2.74%
Expected dividend rate	0.00%	0.00%
Fair value of options granted (in dollars)	$ 664,000
Minimum [Member]
Share-based compensation
Vesting period	1 year
Maximum [Member]
Share-based compensation
Vesting period	3 years
Stock Options [Member]
Share-based compensation
Granted (in shares)	1,328,718	224,000
Stock Issued During Period In Lieu of Cash Bonus		159,100
Exercise price (in dollars per share)		$ 1.94
Contractual life	10 years	10 years
Stock Options [Member] \| Minimum [Member]
Share-based compensation
Exercise price (in dollars per share)	$ 0.87	$ 1.85
Vesting period		3 years
Stock Options [Member] \| Maximum [Member]
Share-based compensation
Exercise price (in dollars per share)	$ 1.21	$ 2.10
Vesting period		4 years
Stock Options [Member] \| Chief Executive Officer [Member]
Share-based compensation
Granted (in shares)	258,618
Stock Options [Member] \| Chief Executive Officer [Member] \| Inducement Stock Options [Member]
Share-based compensation
Granted (in shares)	600,000
Stock Options [Member] \| Director [Member]
Share-based compensation
Estimated common stock subject to options issued	381,000
Stock Options [Member] \| Other Employees [Member]
Share-based compensation
Granted (in shares)	530,000

The Forfeiture rate assumption that is used in valuing an option on its own shares.

No definition available.

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- Definition

The estimated number of common stock to be issued for options granted.

+ References

No definition available.

+ Details

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- Definition

Fair value of options granted in period. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

+ References

No definition available.

+ Details

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- Definition

Number of stock (or other type of equity) issued during the period as a result of in lieu of cash bonus.

+ References

No definition available.

+ Details

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

Rate of weighted-average expected volatility for award under share-based payment arrangement.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

+ Details

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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