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Stock Based Compensation -Valuation Assumptions Non-Employees (Details) - USD ($) | 11 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2014 | Dec. 31, 2016 | Dec. 31, 2015
Stock Option Plans |  |  |
Stock-based compensation expense |  | $ 3,828,000 | $ 428,000
Weighted-average assumptions used to estimate fair value of share-based awards |  |  |
Expected term (in years) | 6 years 1 month 6 days | 6 years | 6 years 1 month 6 days
Expected dividend yield | 0.00% | 0.00% | 0.00%
Non-employee stock options |  |  |
Stock Option Plans |  |  |
Stock-based compensation expense |  | $ 142,500 | $ 42,848
Weighted-average assumptions used to estimate fair value of share-based awards |  |  |
Risk-free interest rate, minimum |  | 1.90% | 1.80%
Risk-free interest rate, maximum |  | 1.94% | 2.20%
Expected Volatility, minimum |  | 92.10% | 82.00%
Expected Volatility, maximum |  | 92.70% | 84.70%
Expected dividend yield |  | 0.00% | 0.00%
Non-employee stock options | Minimum |  |  |
Weighted-average assumptions used to estimate fair value of share-based awards |  |  |
Expected term (in years) |  | 8 years 1 month 6 days | 9 years 1 month 6 days
Non-employee stock options | Maximum |  |  |
Weighted-average assumptions used to estimate fair value of share-based awards |  |  |
Expected term (in years) |  | 8 years 7 months 6 days | 10 years

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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + 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://www.xbrl.org/2003/role/presentationRef -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=6415400&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 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 Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -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=27013229&loc=d3e301413-122809 + Details
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