Note 3 - Acquisition of Businesses (Details) - Accel AB Preliminary Purchase Price Allocation (USD $) In Thousands, unless otherwise specified	Mar. 30, 2013	Dec. 29, 2012
Note 3 - Acquisition of Businesses (Details) - Accel AB Preliminary Purchase Price Allocation [Line Items]
Goodwill	$ 131,850	$ 133,592
	23,865
Accel AB [Member] \| Distribution Rights [Member]
Note 3 - Acquisition of Businesses (Details) - Accel AB Preliminary Purchase Price Allocation [Line Items]
Amortizable intangible assets	1,321
Accel AB [Member] \| Trademarks [Member]
Note 3 - Acquisition of Businesses (Details) - Accel AB Preliminary Purchase Price Allocation [Line Items]
Amortizable intangible assets	1,259
Accel AB [Member] \| Patents and Licenses [Member]
Note 3 - Acquisition of Businesses (Details) - Accel AB Preliminary Purchase Price Allocation [Line Items]
Amortizable intangible assets	2,435
Accel AB [Member]
Note 3 - Acquisition of Businesses (Details) - Accel AB Preliminary Purchase Price Allocation [Line Items]
Cash	344
Current assets, net	8,643
Property, plant and equipment	3,731
Other assets	7
Goodwill	11,536
Current liabilities	$ (5,411)

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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