This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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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.

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The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

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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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Amount of cost (reversal of cost) for pension and other postretirement benefits.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Note 12 - Segment Information (Details Textual) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 30, 2017	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2016	Oct. 01, 2016	Jul. 02, 2016	Apr. 02, 2016	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Number of Operating Segments									3
Business Combination, Acquisition Related Costs	$ 1,400	$ 4,800	$ 300	$ 1,500	$ 3,200	$ 5,900	$ 6,100	$ 6,200
Goodwill and Intangible Asset Impairment										$ 14,809
Legal Fees	$ 700	$ 1,500			1,200	$ 900	100	400
Sales Revenue, Goods, Net [Member] \| Geographic Concentration Risk [Member] \| Outside the United States [Member]
Concentration Risk, Percentage									69.00%
Sales Revenue, Goods, Net [Member] \| Geographic Concentration Risk [Member] \| CHINA
Concentration Risk, Percentage									26.00%
Sales Revenue, Goods, Net [Member] \| Customer Concentration Risk [Member] \| Arrow Electronics Inc. [Member]
Concentration Risk, Percentage									10.60%
Facility Relocation [Member]
Restructuring Charges					$ 100		700	1,000
Facility Closing [Member]
Restructuring Charges							$ 300	$ 1,600
Selling, General and Administrative Expenses [Member]
Business Combination, Acquisition Related Costs											4,600
Pension and Other Postretirement Benefits Cost (Reversal of Cost)											31,900
Legal Fees											3,600
Cost of Sales [Member] \| Facility Relocation [Member]
Restructuring Charges											$ 5,200
Other Segments [Member] \| Selling, General and Administrative Expenses [Member]
Business Combination, Acquisition Related Costs									$ 8,000	29,200
Restructuring Charges									$ 2,200	2,500
Other Segments [Member] \| Cost of Sales [Member]
Goodwill and Intangible Asset Impairment										14,800
Other Segments [Member] \| Cost of Sales [Member] \| Facility Relocation [Member]
Restructuring Charges										1,600
Other Segments [Member] \| Operating Income (Loss) [Member] \| Facility Closing [Member]
Restructuring Charges										$ 1,900