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Stock-Based Compensation - Assumptions (Details) - shares | 3 Months Ended
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Mar. 31, 2021 | Mar. 31, 2020
Performance-based awards |  |
Valuation of Stock Option Grants to Employees |  |
Expected volatility, maximum | 60.00% |
Risk free interest rate, minimum | 0.80% |
Risk free interest rate, maximum | 0.95% |
Performance-based awards | Minimum |  |
Valuation of Stock Option Grants to Employees |  |
Expected term (years) | 7 years 3 months |
Performance-based awards | Maximum |  |
Valuation of Stock Option Grants to Employees |  |
Expected term (years) | 10 years |
Expected dividend yield | 0.00% |
Employee and non-employee stock options |  |
Stock Based Compensation |  |
Options granted (in shares) | 150,000 |
Employee stock options |  |
Valuation of Stock Option Grants to Employees |  |
Expected volatility | 55.33% |
Expected volatility, minimum |  | 49.94%
Expected volatility, maximum |  | 58.53%
Expected dividend yield | 0.00% | 0.00%
Risk free interest rate | 1.13% |
Risk free interest rate, minimum |  | 0.44%
Risk free interest rate, maximum |  | 1.70%
Employee stock options | Minimum |  |
Valuation of Stock Option Grants to Employees |  |
Expected term (years) |  | 5 years 3 months 7 days
Employee stock options | Maximum |  |
Valuation of Stock Option Grants to Employees |  |
Expected term (years) | 10 years | 10 years
Non-employee stock options |  |
Stock Based Compensation |  |
Options granted (in shares) | 34,376 |
Options unvested (in shares) | 2,917 |

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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=116856206&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=116856206&loc=d3e5070-113901 + Details
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- Definition The estimated measure of the maximum 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 No definition available. + Details
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- Definition The estimated measure of the minimum 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 No definition available. + 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=116856206&loc=d3e5070-113901 + Details
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- Definition The maximum risk-free interest rate assumption that is used in valuing an option on its own shares. + References No definition available. + Details
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- Definition The minimum risk-free interest rate assumption that is used in valuing an option on its own shares. + References No definition available. + Details
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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 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=116856206&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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