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Capital Stock, Stock Plans and Stock-Based Compensation - Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions (Details) - $ / shares | 9 Months Ended
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Sep. 30, 2020 | Sep. 30, 2019
Employee Stock Option Granted [Member] |  |  |
Weighted-average fair value per option |  |  | $ 1.46
Dividend yield |  |  | 0.00%
Expected option life | [1] |  | 5 years
Employee Stock Option Granted [Member] | Maximum [Member] |  |  |
Risk -free interest rate | [2] |  | 2.58%
Expected volatility of stock | [3] |  | 51.38%
Employee Stock Option Granted [Member] | Minimum [Member] |  |  |
Risk -free interest rate | [2] |  | 1.40%
Expected volatility of stock | [3] |  | 48.67%
Outside Director Stock Options Granted [Member] |  |  |
Weighted-average fair value per option |  | $ 4.66 | $ 2.27
Risk -free interest rate | [2] |  | 2.08%
Expected volatility of stock | [3] |  | 54.28%
Dividend yield |  | 0.00% | 0.00%
Expected option life | [1] | 10 years | 10 years
Outside Director Stock Options Granted [Member] | Maximum [Member] |  |  |
Risk -free interest rate | [2] | 1.61% |
Expected volatility of stock | [3] | 56.68% |
Outside Director Stock Options Granted [Member] | Minimum [Member] |  |  |
Risk -free interest rate | [2] | 0.59% |
Expected volatility of stock | [3] | 55.83% |
[1] | The expected option life is based on historical exercises and post-vesting data.
[2] | The risk-free interest rate is based on the U.S. Treasury yield in effect at the grant date over the expected term of the option.
[3] | The expected volatility is based on historical volatility from our traded Common Stock over the expected term of the option.

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- Definition Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award. + References No definition available. + Details
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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 Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition 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 Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. + 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 -Subparagraph (f)(2)(iv) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + 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 -Subparagraph (f)(2)(i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.D.2) -URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809 + Details
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