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Note 4 - Acquisition of Businesses - Preliminary Price Allocation (Details) - USD ($) $ in Thousands	Apr. 04, 2016	Mar. 25, 2016	Oct. 01, 2015	Jul. 02, 2016	Jan. 02, 2016
PolySwitch [Member] \| Patented and Unpatented Technologies [Member]
Intangible assets, other than goodwill		$ 56,425
PolySwitch [Member] \| Customer Relationships [Member]
Intangible assets, other than goodwill		39,720
PolySwitch [Member]
Business Combination, Consideration Transferred		350,000
Cash		16,958
Property, plant and equipment		57,042
Goodwill		165,797
Current liabilities		(53,389)
Other non-current liabilities		(5,566)
		350,000
Other current assets, net		57,114
Other long-term assets		$ 15,899
Menber's S.p.A. [Member] \| Patented and Unpatented Technologies [Member]
Intangible assets, other than goodwill	$ 389
Menber's S.p.A. [Member] \| Customer Relationships [Member]
Intangible assets, other than goodwill	3,066
Menber's S.p.A. [Member] \| Trademarks and Trade Names [Member]
Intangible assets, other than goodwill	1,849
Menber's S.p.A. [Member]
Payments to Acquire Businesses, Gross	17,798
Additional consideration payable	919
Business Combination, Consideration Transferred	18,717
Cash	15
Current assets, net	13,287
Property, plant and equipment	1,558
Goodwill	7,364
Current liabilities	(7,367)
Other non-current liabilities	(1,444)
	$ 18,717
Sigmar [Member] \| Patents [Member]
Intangible assets, other than goodwill			$ 2,845
Sigmar [Member]
Payments to Acquire Businesses, Gross			5,845
Additional consideration payable			844
Business Combination, Consideration Transferred			6,689
Cash			230
Current assets, net			4,011
Property, plant and equipment			1,097
Goodwill			2,552
Current liabilities			(1,478)
Other non-current liabilities			(2,568)
			$ 6,689
Goodwill				$ 363,341	$ 189,767