Equity - Stock Options - Activity (Details) - $ / shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based compensation
Outstanding shares, ending balance	880,277	993,860
Granted (in shares)	1,328,718	224,000
Forfeited/Expired/Exchanged - (in shares)	(77,937)	(337,583)
Outstanding shares, beginning balance	2,131,058	880,277	993,860
Exercisable at December 31, Options (in shares)	1,461,073	587,962
Outstanding - Weighted Average Exercise Price (in dollars per share)	$ 4.32	$ 4.81
Granted - Weighted Average Exercise Price (in dollars per share)	1.32	1.94
Forfeited/Expired/Exchanged - Weighted Average Exercise Price (in dollars per share)	2.11	4.19
Outstanding - Weighted Average Exercise Price (in dollars per share)	2.53	4.32	$ 4.81
Exercisable - Weighted Average Exercise Price (in dollars per share)	2.90	$ 5.17
Vest over the estinmated fair value	$ 2.25
Granted - Weighted Average Remaining Contractual Life (in years)	9 years 1 month 28 days	9 years 2 months 23 days
Stock options, Contractual life (in years)	7 years 11 months 27 days	6 years 5 months 27 days	6 years 11 months 9 days
Stock options, Contractual life (in years)		9 years 15 days
Exercisable - Weighted Average Remaining Contractual Life (in years)	7 years 6 months 29 days	6 years 5 months 27 days
Minimum [Member]
Share-based compensation
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	1 year
Maximum [Member]
Share-based compensation
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years

Weighted average remaining contractual term for options granted during the period.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Vest Over Fair Value of Stock Option

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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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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.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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- Definition

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

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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