Represents the number of common stock currently outstanding in respect of RSUs.

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Number of other than options vested.

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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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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 share-based awards, other than options, awarded to employees as compensation.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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).

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The weighted average fair value at grant date for nonvested equity-based awards issued 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).

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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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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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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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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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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STOCK-BASED COMPENSATION - 2015 EIP Restricted Stock Units (Details) - 2015 EIP Plan - Restricted Stock Units - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended
	Mar. 04, 2019	Feb. 27, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Stock Awards
Number of common shares outstanding in respect of RSUs			228,781		216,304
Number of Shares
Balance at the beginning of the period (in shares)			149,170
Granted (in shares)	106,079	37,346	106,079
Vested (in shares)			(12,477)
Balance at the end of the period (in shares)			242,772
Weighted Average Fair Value
Balance at the beginning of the period (in dollars per share)			$ 12.42
Granted (in dollars per share)			8.39
Vested (in dollars per share)			13.69
Balance at the end of the period (in dollars per share)			$ 10.59
Weighted-average remaining contractual life			1 year 8 months 12 days
Additional disclosures
Total fair value of shares vested			$ 107	$ 0
Unrecognized compensation cost related to nonvested stock awards
Unrecognized compensation cost			$ 1,294
Weighted-average period for recognition of unrecognized compensation cost			1 year 8 months 12 days
General and Administrative Expense
Additional disclosures
Recognized nonvested stock amortization expense			$ 271	$ 366
Vested RSUs
Number of Shares
Number of shares vested			306,712
Weighted Average Fair Value
Vested (in dollars per share)			$ 11.30
Other Individuals
Stock Awards
Vesting period of awards			3 years