Discontinued Operations - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		1 Months Ended	3 Months Ended	9 Months Ended
	Sep. 26, 2014	Sep. 27, 2013 segment	Sep. 26, 2014 segment	Sep. 27, 2013	Sep. 27, 2013 HFC business [Member]	Mar. 29, 2013 HFC business [Member]	Sep. 26, 2014 HFC business [Member]	Sep. 27, 2013 HFC business [Member]	Mar. 05, 2013 Aurora [Member] HFC business [Member]	Sep. 27, 2013 Aurora [Member] HFC business [Member]	Sep. 27, 2013 Aurora [Member] HFC business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gross proceeds from sale of cable access HFC business								$ 46,000,000	$ 46,000,000
Gain on disposal, net of taxes			0	14,813,000	(6,000)			14,813,000		14,800,000	15,000,000
Adjustment to prior period gain (loss) on disposal, net of tax											(200,000)
Number of reporting units (in segment)		1	1
Carrying value of goodwill based on the fair value					14,547,000			14,547,000
Goodwill impairment						0
Operating Income (Loss)	$ (3,538,000)	$ (2,555,000)	$ (19,409,000)	$ (22,026,000)			$ 0