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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.

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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.

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- Definition

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

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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.

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- Definition

Gross number of share options (or share units) granted during the period.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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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.

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Share-based Compensation - Assumptions Used in Determining Fair Value of Options (Details) - Stock options - $ / shares	1 Months Ended		12 Months Ended
	Jul. 31, 2018	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Stock options, restricted stock and performance stock options
Options granted (in shares)			1,753,539	570,432	859,257
Exercise price (in dollars per share)			$ 6.786	$ 7.220	$ 10.385
Weighted average key assumptions used in determining the fair value of options granted
Estimated dividend yield (as a percent)			0.00%	0.00%	0.00%
Volatility (annual) (as a percent)			60.00%	60.00%	60.00%
Expected life of option in years			6 years 1 month 17 days	6 years 22 days	6 years 1 month 24 days
Weighted-average option fair value at grant (in dollars per share)			$ 3.930	$ 4.090	$ 5.800
Weighted average
Weighted average key assumptions used in determining the fair value of options granted
Weighted-average risk-free interest rate (as a percent)			2.75%	2.01%	1.18%
Minimum
Stock options, restricted stock and performance stock options
Exercise price (in dollars per share)			$ 4.76
Maximum
Stock options, restricted stock and performance stock options
Exercise price (in dollars per share)			$ 10.40
Neos Therapeutics, Inc. 2015 Stock Option and Incentive Plan
Stock options, restricted stock and performance stock options
Options granted (in shares)			953,539
Neos Therapeutics, Inc 2018 Inducement Plan \| Chief Executive Officer
Stock options, restricted stock and performance stock options
Options granted (in shares)	200,000	600,000
Exercise price (in dollars per share)	$ 5.55	$ 6.20