Note 7 - Fair Value of Assets and Liabilities (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 30, 2017	Jan. 02, 2016
Intangible Assets, Net (Excluding Goodwill)	$ 213,027	$ 203,850
Goodwill	403,544	453,414	$ 189,767
Industrial [Member]
Goodwill	43,194	38,626	$ 51,259
Industrial [Member] \| Custom Products Reporting Unit [Member]
Impairment of Intangible Assets (Excluding Goodwill)	6,015
Goodwill	0
Industrial [Member] \| Custom Products Reporting Unit [Member] \| Trade Names [Member]
Impairment of Intangible Assets (Excluding Goodwill)	3,800
Intangible Assets, Net (Excluding Goodwill)	700
Industrial [Member] \| Custom Products Reporting Unit [Member] \| Customer Relationships [Member]
Impairment of Intangible Assets (Excluding Goodwill)	2,200
Intangible Assets, Net (Excluding Goodwill)	0
Fair Value, Measurements, Recurring [Member]
Assets, Fair Value Disclosure	0	0
Financial and Nonfinancial Liabilities, Fair Value Disclosure	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Paragraph 1
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+ References

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-Publisher FASB
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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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