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A premium of additional restricted stock, as a percentage, granted when opting to receive stock in lieu of cash.

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Shares Awarded, Percentage Of Original Target

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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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Unrecognized cost of unvested options awarded to employees as compensation.

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Amount of addition (reduction) to the amount at which a liability could be incurred (settled) in a current transaction between willing parties.

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

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The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the 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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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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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross 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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Number of share instruments newly issued under a share-based compensation plan.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Percentage of vesting of share-based compensation awards.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Share-Based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands		4 Months Ended		36 Months Ended	161 Months Ended
	Feb. 09, 2018 shares	Dec. 19, 2018 USD ($) plan $ / shares shares	Dec. 20, 2017 USD ($)	Dec. 19, 2018 USD ($) plan shares	Jun. 06, 2018 shares	Aug. 29, 2018 shares	Dec. 05, 2015 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock plans \| plan		2		2
Share-based payment award, options, forfeitures (in shares)		71,983
Stock Options [Abstract]
Share-based payment award, options, outstanding (in shares)		1,494,129		1,494,129		1,653,414
Share-based payment award, compensation not yet recognized, stock options \| $		$ 200		$ 200
Restricted Stock Units and Performance Based Incentive Plan [Abstract]
Share based payment award, liability converted to equity \| $		$ 496
Stock Options
Stock Options [Abstract]
Share-based payment award, compensation not yet recognized, period for recognition		1 year 8 months 1 day
Restricted Stock Units and Performance Based Incentive Plan [Abstract]
Share-based payment award, compensation not yet recognized, period for recognition		1 year 8 months 1 day
Restricted Stock Units (RSUs)
Stock Options [Abstract]
Share-based payment award, compensation not yet recognized, period for recognition		1 year 7 months 24 days
Restricted Stock Units and Performance Based Incentive Plan [Abstract]
Share-based payment award, award vesting period		3 years
Share-based payment award, compensation not yet recognized, share-based awards other than options \| $		$ 600		$ 600
Share-based payment award, compensation not yet recognized, period for recognition		1 year 7 months 24 days
Vested (in shares)		124,618
Target number of shares for distribution (in shares)		370,182		370,182		517,291
Performance Based Incentive Plan
Stock Options [Abstract]
Share-based payment award, compensation not yet recognized, stock options \| $		$ 900		$ 900
Share-based payment award, compensation not yet recognized, period for recognition		1 year 8 months 5 days
Restricted Stock Units and Performance Based Incentive Plan [Abstract]
Share-based payment award, award vesting period		3 years
Share-based payment award, compensation not yet recognized, period for recognition		1 year 8 months 5 days
Share-based payment award, fair value assumptions, expected volatility rate, minimum		0.00%
Share-based payment award, fair value assumptions, expected volatility rate, maximum		200.00%
Vested (in shares)		187,883
Share-based compensation awarded, percent of original target		50.00%
Target number of shares for distribution (in shares)		353,430		353,430		373,294
Performance Based Incentive Plan \| Fair Value, Measurements, Recurring
Restricted Stock Units and Performance Based Incentive Plan [Abstract]
Compensation share based arrangement, liability, increase (decrease) \| $		$ (21)
Selling, General and Administrative Expense \| Performance Based Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense \| $		$ 120	$ 117
Non Employee Directors Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, number of shares authorized (in shares)		2,100,000		2,100,000
Share-based payment award, shares issued (in shares)	1,300,000
Share-based payment award, options, forfeitures (in shares)		100,000
Share-based payment award, number of shares available for grant (in shares)		1,000,000		1,000,000
Stock Options [Abstract]
Share-based payment award, expiration period		10 years
Share-based payment award, options, grants (in shares)		0
Share-based payment award, options, outstanding (in shares)		0		0
Restricted Stock Awards [Abstract]
Restricted stock and unit awards granted to named executive officers, percentage		20.00%
Non Employee Directors Stock Plan \| First Anniversary
Stock Options [Abstract]
Share-based payment award, award vesting rights, percentage		100.00%
Non Employee Directors Stock Plan \| Selling, General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense \| $		$ 122	152
Employee Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, number of shares authorized (in shares)							4,100,000
Share-based payment award, shares issued (in shares)				7,300,000
Share-based payment award, options, forfeitures (in shares)					4,100,000
Share-based payment award, number of shares available for grant (in shares)		900,000		900,000
Stock Options [Abstract]
Share-based payment award, expiration period		10 years
Share-based payment award, options, outstanding (in shares)		1,494,129		1,494,129
Share-based payment award, exercise price range, lower range limit (usd per share) \| $ / shares		$ 2.82
Share-based payment award, exercise price range, upper range limit (usd per share) \| $ / shares		$ 5.95
Employee Stock Plan \| First Anniversary
Stock Options [Abstract]
Share-based payment award, award vesting rights, percentage		50.00%
Employee Stock Plan \| Second Anniversary
Stock Options [Abstract]
Share-based payment award, award vesting rights, percentage		25.00%
Employee Stock Plan \| Third Anniversary
Stock Options [Abstract]
Share-based payment award, award vesting rights, percentage		25.00%
Employee Stock Plan \| Selling, General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense \| $		$ 184	$ 289