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Equity Plans - Narrative (Details) - shares | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2020 | Feb. 18, 2020 | May 31, 2018
Equity Plans |  |  |
Average volatality | 75.00% |  |
Percentage of volatality of stock options since IPO | 25.00% |  |
2016 Equity Incentive Plan |  |  |
Equity Plans |  |  |
Number of shares available for issuance | 632,901 |  |
Restricted stock unit incentive awards granted in 2018 |  |  |
Equity Plans |  |  |
Expiration period | 10 years |  |
Number of shares authorized |  |  | 750,000
Additional shares for issuance |  | 500,000 |
Number of shares available for issuance | 780,000 |  |
Stock options - employees, consultants, directors | 2016 Equity Incentive Plan |  |  |
Equity Plans |  |  |
Expiration period | 10 years |  |

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- Definition Represents the percentage of average volatility for comparable publicly traded biopharmaceutical companies over a period equal to the expected term of the stock option grants, used in the calculation of expected volatility. + References No definition available. + Details
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- Definition Represents the percentage of volatility of stock price since its initial public offering used in the calculation of expected volatility. + References No definition available. + Details
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- Definition Aggregate number of common shares reserved for future issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Number of shares authorized for issuance under share-based payment arrangement. + 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 (a)(3) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + 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 -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the 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 (a)(2) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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