The percentage of revenue recognized upon customer acceptance.

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- Definition

The percentage of revenue recognized upon shipment and passage of title.

+ References

No definition available.

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- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
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- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.4)
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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
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- Definition

Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 13.A.3)
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- Definition

Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

Total loss recognized during the period from the impairment of goodwill plus the loss recognized in the period resulting from the impairment of the carrying amount of intangible assets, other than goodwill.

+ References

No definition available.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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- Definition

Amount of unearned revenue or income classified as other, expected to be taken into income within one year or the normal operating cycle, if longer.

+ References

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- Definition

The amount of a reclassification adjustment made to prior period financial statement amounts.

+ References

No definition available.

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Note 1 - Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Oct. 01, 2016	Jun. 24, 2017	Jun. 25, 2016	Jun. 24, 2017	Jun. 25, 2016	Dec. 31, 2016
Allowance for Doubtful Accounts Receivable, Current		$ 100		$ 100		$ 100
Number of Operating Segments				1
Goodwill and Intangible Asset Impairment	$ 0
Foreign Currency Transaction Gain (Loss), Realized		(1,200)	$ (300)	$ (2,500)	$ (800)
Percentage of Revenue Recognized upon Customer Acceptance				20.00%
Percentage of Revenue Recognized upon Shipment and Passage of Title				80.00%
Other Deferred Credits, Current		6,300		$ 6,300		6,900
Deferred Revenue		8,200		8,200		9,300
Accumulated Other Comprehensive Income (Loss), Net of Tax		$ (20,604)		$ (20,604)		$ (27,882)
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		46,000	773,000	152,000	775,000
Adjustments for New Accounting Principle, Early Adoption [Member] \| Three Months Ended June 25, 2016 [Member]
Prior Period Reclassification Adjustment			$ 100
Adjustments for New Accounting Principle, Early Adoption [Member] \| Six Months Ended June 25, 2016 [Member]
Prior Period Reclassification Adjustment					$ (100)