Note 15 - Business Unit Segment Information (Details Textual) - USD ($)	3 Months Ended								6 Months Ended	12 Months Ended
	Jan. 02, 2016	Sep. 26, 2015	Jun. 27, 2015	Mar. 28, 2015	Dec. 27, 2014	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Jun. 28, 2014	Jan. 02, 2016	Jan. 02, 2016	Dec. 27, 2014	Dec. 28, 2013
Cost of Sales [Member] | Facility Relocation [Member]
Restructuring Charges											$ 5,200,000
Cost of Sales [Member] | Sym Com Inc [Member]
Noncash Charges Related To Inventory Stepup												$ 2,800,000
Cost of Sales [Member] | Hamlin Inc [Member]
Noncash Charges Related To Inventory Stepup													$ 1,500,000
Cost of Sales [Member]
Severance Costs												2,700,000
Selling, General and Administrative Expenses [Member] | Sym Com Inc [Member]
Business Combination, Acquisition Related Costs												400,000
Selling, General and Administrative Expenses [Member] | Hamlin Inc [Member]
Business Combination, Acquisition Related Costs													1,700,000
Selling, General and Administrative Expenses [Member] | Other Segments [Member]
Asset Impairment Charges												100,000
Selling, General and Administrative Expenses [Member]
Business Combination, Acquisition Related Costs											4,600,000
Pension and Other Postretirement Benefit Expense											31,900,000
Legal Fees											3,600,000	2,200,000
Other Nonrecurring (Income) Expense											200,000
Severance Costs											$ 500,000
Asset Impairment Charges												300,000
Research and Development Expense [Member] | Other Segments [Member]
Asset Impairment Charges												200,000
Facility Relocation [Member]
Restructuring Charges	$ 2,100,000	$ 1,200,000	$ 900,000	$ 1,000,000
Sym Com Inc [Member]
Business Combination, Acquisition Related Costs							$ 200,000
Noncash Charges Related To Inventory Stepup							1,400,000	$ 1,400,000	$ 1,400,000
Severance Costs							$ 2,000,000
Sales Revenue, Goods, Net [Member] | Geographic Concentration Risk [Member] | Outside the United States [Member]
Concentration Risk, Percentage											60.00%
Sales Revenue, Goods, Net [Member] | Geographic Concentration Risk [Member] | CHINA
Concentration Risk, Percentage											22.00%
Number of Operating Segments											3,000,000
Restructuring Charges					$ 2,200,000	$ 1,100,000
Business Combination, Acquisition Related Costs	4,000,000	300,000	200,000	200,000	300,000						$ 4,600,000	$ 500,000	1,700,000
Legal Fees	(100,000)	900,000	$ 1,700,000	$ 1,200,000
Other Nonrecurring (Income) Expense	$ (300,000)	$ 100,000
Asset Impairment Charges					$ 300,000						$ 0		0
Impairment And Equity In Net Loss Of Unconsolidated Affiliate													$ 10,678,000