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.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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.

+ References

No definition available.

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- Definition

Value, before forfeitures, of stock or other type of equity granted of any equity-based compensation plan other than an employee stock ownership plan (ESOP).

+ References

No definition available.

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- Definition

Value of stock related to Restricted Stock Awards issued during the period, net of the stock value of such awards forfeited.

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Stock-based Compensation - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended		12 Months Ended
	Oct. 31, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock unit expense, net	$ 245	$ 716	$ 650
2015 Omnibus Incentive Plan \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted in period		70,000		111,281	390,352
Stock granted, value		$ 404		$ 909	$ 4,100
Share-based compensation expense			$ 650
Share-based compensation expense not yet recognized		$ 2,200