Summary of Option and Stock Appreciation Rights Activity (Details)	6 Months Ended
Jun. 30, 2020 $ / shares shares
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of Options/SARs, Outstanding, Beginning Balance \| shares	1,857,599
Weighted Average Exercise Price per Share, Outstanding, Beginning Balance	$ 2.22
Number of Options/SARs, Granted \| shares	897,250
Weighted Average Exercise Price per Share, Granted	$ 4.52
Number of Options/SARs, Exercised \| shares	(80,785)
Weighted Average Exercise Price per Share, Exercised	$ 1.22
Number of Options/SARs, Forfeited \| shares	(137,164)
Weighted Average Exercise Price per Share, Forfeited	$ 5.86
Number of Options/SARs, Outstanding, Ending Balance \| shares	2,536,900
Weighted Average Exercise Price per Share, Outstanding, Ending Balance	$ 2.87
Range One [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Range of Exercise Price, Lower Limit	0.74
Range of Exercise Price, Upper Limit	36.20
Range Two [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Range of Exercise Price, Lower Limit	3.98
Range of Exercise Price, Upper Limit	5.13
Range Three [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Range of Exercise Price, Lower Limit	0.74
Range of Exercise Price, Upper Limit	2.03
Range Four [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Range of Exercise Price, Lower Limit	0.74
Range of Exercise Price, Upper Limit	36.20
Range Five [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Range of Exercise Price, Lower Limit	0.74
Range of Exercise Price, Upper Limit	$ 35.20

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.

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

+ References

No definition available.

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

+ 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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- Definition

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

+ References

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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No definition available.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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No definition available.

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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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- 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.

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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- Definition

Number of share options (or share units) exercised during the current period.

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