Stock Options Oustanding and Exercisable (Details)	9 Months Ended
Sep. 30, 2020 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding Options Number $1.70 To $1.93 \| shares	829,922
Outstanding Options Aggregate Intrinsic Value $1.70 to $1.93 \| $	$ 0
Outstanding Options Weighted Average Remaining Contractual Term Years $1.70 To $1.93	4 years 5 months 23 days
Exercisable Options Number $1.70 To $1.93 \| shares	739,921
Exercisable Options Weighted Average Exercise Price $1.70 To $1.93	$ 1.84
Exercisable Options Aggregate Intrinsic Value $1.70 To $1.93 \| $	$ 0
Exercisable Options Weighted Average Remaining Contractual Term Years $1.70 To $1.93	3 years 9 months 21 days
Outstanding Options Number $2.39 \| shares	3,369,643
Outstanding Options Aggregate Intrinsic Value $2.39 \| $	$ 0
Outstanding Options Weighted Average Remaining Contractual Term Years $2.39	6 years 4 months 17 days
Exercisable Options Number $2.39 \| shares	3,369,643
Exercisable Options Weighted Average Exercise Price $2.39	$ 2.39
Exercisable Options Aggregate Intrinsic Value $2.39 \| $	$ 0
Exercisable Options Weighted Average Remaining Contractual Term Years $2.39	6 years 4 months 17 days
Outstanding Options Number $3.15 To $3.26 \| shares	430,000
Outstanding Options Aggregate Intrinsic Value $3.15 To $3.26 \| $	$ 0
Outstanding Options Weighted Average Remaining Contractual Term Years $3.15 To $3.26	4 years 2 months 15 days
Exercisable Options Number $3.15 To $3.26 \| shares	430,000
Exercisable Options Weighted Average Exercise Price $3.15 To $3.26	$ 3.21
Exercisable Options Aggregate Intrinsic Value $3.15 To $3.26 \| $	$ 0
Exercisable Options Weighted Average Remaining Contractual Term Years $3.15 To $3.26	4 years 2 months 15 days
Outstanding Options Number Total \| shares	4,629,565
Outstanding Options Aggregate Intrinsic Value Total \| $	$ 0
Outstanding Options Weighted Average Remaining Contractual Term Years Total	5 years 10 months 2 days
Exercisable Options Number Total \| shares	4,539,564
Exercisable Options Weighted Average Exercise Price Total	$ 2.38
Exercisable Options Aggregate Intrinsic Value Total \| $	$ 0
Exercisable Options Weighted Average Remaining Contractual Term Years Total	5 years 9 months 3 days
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate	0.26%
Share based Compensation Arrangement By Share based Payment Award Fair Value Assumptions Expected Term	5 years
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate	49.00%
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate	0.00%
Range 170to 193 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Exercise Price	$ 1.82
Range 239 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Exercise Price	2.39
Range 315to 326 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Exercise Price	3.21
Range 170to 326 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Exercise Price	2.36
Minimum [Member] \| Range 170to 193 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Exercise Price	1.70
Minimum [Member] \| Range 315to 326 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Exercise Price	3.15
Minimum [Member] \| Range 170to 326 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Exercise Price	1.70
Maximum [Member] \| Range 170to 193 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Exercise Price	1.93
Maximum [Member] \| Range 315to 326 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Exercise Price	3.26
Maximum [Member] \| Range 170to 326 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Exercise Price	$ 3.26

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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.

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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.

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

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

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