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Strategic Technology Transactions, Goodwill and Purchased Intangible Assets - Additional Information (Detail) (USD $)	0 Months Ended
	Dec. 31, 2012	Dec. 27, 2014	Dec. 28, 2013
Business Acquisition [Line Items]
Accumulated Amortization		$ 30,359,000	$ 25,536,000
Duma Technology [Member]
Business Acquisition [Line Items]
Accumulated Amortization		864,000	408,000
Microwave Communications Equipment [Member] \| Duma Technology [Member]
Business Acquisition [Line Items]
Accumulated Amortization		200,000
Ismeca [Member]
Business Acquisition [Line Items]
Purchase price of acquisition	90,800,000
Purchase price of acquisition, cash reserves	57,100,000
Purchase price of acquisition, liabilities assumed	33,700,000
Amounts excluded related to trade names		3,600,000	4,000,000
Rasco Technology [Member]
Business Acquisition [Line Items]
Amounts excluded related to trade names		$ 2,100,000	$ 2,400,000