Note 2 - Acquisition of Businesses (Details) - Final Purchase Price Allocations (USD $) In Thousands, unless otherwise specified	Mar. 29, 2014	Dec. 28, 2013
Note 2 - Acquisition of Businesses (Details) - Final Purchase Price Allocations [Line Items]
Goodwill	$ 199,415	$ 186,464
SymCom, Inc. [Member] \| Trademarks [Member]
Note 2 - Acquisition of Businesses (Details) - Final Purchase Price Allocations [Line Items]
Amortizable intangible assets	17,230
SymCom, Inc. [Member] \| Patents [Member]
Note 2 - Acquisition of Businesses (Details) - Final Purchase Price Allocations [Line Items]
Amortizable intangible assets	1,500
SymCom, Inc. [Member]
Note 2 - Acquisition of Businesses (Details) - Final Purchase Price Allocations [Line Items]
Cash	325
Current assets, net	9,704
Property, plant and equipment	11,193
Goodwill	13,375
Other non-current assets	20
Current liabilities	(1,022)
Total purchase price allocation	52,325
Hamlin, Inc. [Member] \| Trademarks [Member]
Note 2 - Acquisition of Businesses (Details) - Final Purchase Price Allocations [Line Items]
Amortizable intangible assets	6,522
Hamlin, Inc. [Member] \| Distribution Rights [Member]
Note 2 - Acquisition of Businesses (Details) - Final Purchase Price Allocations [Line Items]
Amortizable intangible assets	35,327
Hamlin, Inc. [Member] \| Patents and Licenses [Member]
Note 2 - Acquisition of Businesses (Details) - Final Purchase Price Allocations [Line Items]
Amortizable intangible assets	16,276
Hamlin, Inc. [Member]
Note 2 - Acquisition of Businesses (Details) - Final Purchase Price Allocations [Line Items]
Cash	15,984
Current assets, net	27,811
Property, plant and equipment	24,728
Goodwill	50,793
Non-current assets	2,452
Current liabilities	(7,309)
Non-current liabilities	(12,217)
Total purchase price allocation	$ 160,367

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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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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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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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

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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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