Aggregate number of common shares reserved for future issuance.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested options awarded to employees as compensation.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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.

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- Definition

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

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No definition available.

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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

Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Share-Based Payments - Additional Information (Details) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2019 USD ($) $ / shares shares	Mar. 31, 2019 $ / shares	May 15, 2018 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares available for issuance			3,000,000
Number of stock option issued	640,158
Grant Date Fair Value \| $ / shares	$ 4.71
Employee and Director Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of stock option issued	640,158
Unrecognized compensation cost related to non-vested stock options outstanding \| $	$ 10.1
Weighted-average remaining vesting period	3 years
Consultants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of stock option issued	0
Non-employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of stock option issued	0
Non-employee Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested stock options outstanding \| $	$ 0.1
Weighted-average remaining vesting period	2 years 3 months 18 days
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Oustanding shares	964
Weighted average granted date fair value \| $ / shares		$ 10.00
Vested RSUs	0
Issuance of shares of common stock in settlement of vested RSUs	0
2018 Omnibus Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares authorized and approved to issue under plan			5,356,114
Common stock remaining available for grant	4,189,661
2016 Omnibus Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares available for issuance			2,356,114