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

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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 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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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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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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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
	Feb. 23, 2021	Feb. 25, 2020	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Stock Awards
Number of common shares outstanding in respect of RSUs			478,848		373,588
Number of Shares
Balance at the beginning of the period (in shares)			298,834
Granted (in shares)	103,599	173,749	103,870
Vested (in shares)			(105,458)
Balance at the end of the period (in shares)			297,246
Number of shares vested			611,355
Weighted Average Grant Date Price, Vested			$ 10.59
Weighted Average Fair Value
Balance at the beginning of the period (in dollars per share)			7.49
Granted (in dollars per share)			9.91
Vested (in dollars per share)			8.29
Balance at the end of the period (in dollars per share)			$ 8.06
Weighted-average remaining contractual life			1 year 10 months 17 days
Additional disclosures
Total fair value of shares vested			$ 1,130	$ 351
Unrecognized compensation cost related to nonvested stock awards
Unrecognized compensation cost			$ 1,534
Weighted-average period for recognition of unrecognized compensation cost			1 year 10 months 17 days
General and Administrative Expense
Additional disclosures
Recognized nonvested stock amortization expense			$ 342	$ 276
Other Individuals
Stock Awards
Vesting period of awards			3 years