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Amount of cost to be recognized for option under share-based payment arrangement.

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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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Number of shares authorized for issuance under share-based payment arrangement.

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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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Share-Based and Other Compensation Matters - Narrative (Details)		3 Months Ended	4 Months Ended		60 Months Ended
	Aug. 12, 2020 USD ($) employee $ / shares shares	Nov. 18, 2020 USD ($)	Dec. 16, 2020 USD ($) plan $ / shares shares	Dec. 18, 2019 USD ($)	Dec. 16, 2020 USD ($) plan $ / shares shares	Aug. 26, 2020 $ / shares shares	Dec. 05, 2015 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock plans \| plan			2		2
Allocated share-based compensation expense \| $		$ 158,000		$ 153,000
Stock Options [Abstract]
Share-based payment award, options, outstanding (in shares)			849,970		849,970	860,501
Share-based payment award, compensation not yet recognized, stock options \| $			$ 0		$ 0
Restricted Stock Units and Performance Based Incentive Plan [Abstract]
Allocated share-based compensation expense \| $		158,000		153,000
Deferred Bonus
Restricted Stock Awards [Abstract]
Total cash bonus available to be earned \| $	$ 200,000
Management
Restricted Stock Awards [Abstract]
Number of employees \| employee	5
Employee Severance [Member]
Restricted Stock Awards [Abstract]
Number of positions eliminated \| employee	8
Total amount of severance that would be paid \| $			$ 1,000,000.0		$ 1,000,000.0
Employee Severance [Member] \| Minimum
Restricted Stock Awards [Abstract]
Percentage of individual's salary	25.00%
Employee Severance [Member] \| Maximum
Restricted Stock Awards [Abstract]
Percentage of individual's salary	100.00%
Restricted Stock Units (RSUs)
Restricted Stock Units and Performance Based Incentive Plan [Abstract]
Share-based payment award, award vesting period			3 years
Restricted Stock Awards [Abstract]
Target number of shares for distribution (in shares)			121,026		121,026	173,808
Unvested shares, fair value (in dollars per share) \| $ / shares			$ 2.47		$ 2.47	$ 2.57
Performance Based Incentive Plan
Restricted Stock Units and Performance Based Incentive Plan [Abstract]
Share-based payment award, award vesting period			3 years
Target number of shares for distribution			373,294		373,294
Restricted Stock
Restricted Stock Awards [Abstract]
Target number of shares for distribution (in shares)	127,000
Grant date fair value \| $	$ 139,000
Unvested shares, fair value (in dollars per share) \| $ / shares	$ 1.095
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 \| $				118,000
Restricted Stock Units and Performance Based Incentive Plan [Abstract]
Allocated share-based compensation expense \| $				118,000
Non Employee Directors Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, number of shares available for grant (in shares)			0		0
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%
Employee Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, number of shares available for grant (in shares)			1,900,000		1,900,000
Share-based payment award, number of shares authorized (in shares)							4,100,000
Share-based payment award, shares issued (in shares)					7,400,000
Share-based payment award, options, forfeitures (in shares)					5,200,000
Stock Options [Abstract]
Share-based payment award, expiration period			10 years
Share-based payment award, options, outstanding (in shares)			849,970		849,970
Share-based payment award, exercise price range, lower range limit (in dollars per share) \| $ / shares			$ 2.82
Share-based payment award, exercise price range, upper range limit (in dollars 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 \| $		25,000		212,000
Restricted Stock Units and Performance Based Incentive Plan [Abstract]
Allocated share-based compensation expense \| $		$ 25,000		$ 212,000