Number of additional common shares reserved for future issuance.

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

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Aggregate number of common shares reserved for future issuance.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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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Discount rate from fair value on offering date that participants pay for shares.

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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 highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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

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No definition available.

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

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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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Price of a single share of a number of saleable stocks of a company.

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Intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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Number of shares issued during the period as a result of an employee stock purchase plan.

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Note 11 - Share-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2018	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018	Dec. 29, 2018	Dec. 31, 2016	Dec. 27, 2015	Sep. 27, 2019	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period				10 years
Share-based Payment Arrangement, Expense		$ 24	$ 121	$ 472	$ 322
Common Stock, Capital Shares Reserved for Future Issuance		975,800		975,800		1,176,474
Share Price									$ 3.04
The 2014 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized		1,125,000		1,125,000						625,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized							500,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		267,551		267,551
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		267,877		267,877
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Offering Date				85.00%
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate		10.00%		10.00%
Additional Shares of Common Stock Reserved for Future Issuance						300,000		300,000
Common Stock, Capital Shares Reserved for Future Issuance						1,400,000		1,100,000
Stock Issued During Period, Shares, Employee Stock Purchase Plans	59,075
Time-based Restricted Stock Units [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total		$ 100		$ 100
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				2 years
Time-based Restricted Stock Units [Member] \| The 2014 Plan [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total		$ 138		$ 138
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance		120,372		120,372		147,372
Dividends Payable		$ 40		$ 40
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Nonvested		$ 366		$ 366
Performance-based Restricted Stock Units [Member] \| The 2014 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance		320,000		320,000		200,000
Dividends Payable		$ 0		$ 0
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount		$ 1,500		$ 1,500
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period				1 year
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period				3 years