Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended	6 Months Ended
	Oct. 01, 2013	Jun. 28, 2014	Jun. 28, 2014	Dec. 28, 2013
Significant Accounting Policies [Line Items]
Net of allowance for doubtful accounts		$ 300,000	$ 300,000	$ 500,000
Goodwill impairment	0
Number of common stock shares excluded from computation of diluted income per share		2,231,000	2,257,000
Deferred revenue		15,300,000	15,300,000	7,400,000
Deferred profit		8,858,000	8,858,000	6,066,000	[1]
Accumulated other comprehensive income		$ 6,476,000	$ 6,476,000	$ 6,651,000	[1]
Semiconductor Equipment [Member]
Significant Accounting Policies [Line Items]
Percent of fair value exceeding carrying value	31.00%
Microwave Communications [Member]
Significant Accounting Policies [Line Items]
Percent of fair value exceeding carrying value	11.00%

[1] Derived from December 28, 2013 audited financial statements