Share-based Compensation - Options (Details) $ / shares in Units, $ in Millions	9 Months Ended
Sep. 30, 2018 USD ($) $ / shares shares
Number of Shares
Number of Shares, Options outstanding, Beginning balance \| shares	1,250
Number of Shares, Options granted \| shares	234,959
Number of Shares, Options exercised \| shares	(1,250)
Number of Shares, Options outstanding, Ending balance \| shares	234,959
Weighted Average Exercise Price
Weighted Average Exercise Price, Options outstanding, Beginning Balance \| $ / shares	$ 9.69
Weighted Average Exercise Price, Granted \| $ / shares	22.31
Weighted Average Exercise Price, Exercised \| $ / shares	9.69
Weighted Average Exercise Price, Options outstanding, Ending Balance \| $ / shares	$ 22.31
Stock Options
Weighted Average Exercise Price
Unrecognized compensation expense \| $	$ 1.5

Unrecognized cost of unvested share-based compensation awards.

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- Definition

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

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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

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Number of share options (or share units) exercised during the current period.

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