Severance, Restructuring and Acquisition Integration Activities - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 28, 2014	Sep. 29, 2013	Sep. 28, 2014 Program	Sep. 29, 2013
Restructuring Cost and Reserve [Line Items]
Severance and other restructuring costs	$ 9,158,000	$ 3,800,000	$ 48,809,000	$ 9,500,000
Number of significant programs			2
Additional severance and other restructuring costs and accelerated depreciation expense	23,000,000		23,000,000
Broadcast Segment [Member]
Restructuring Cost and Reserve [Line Items]
Severance and other restructuring costs		3,200,000		7,600,000
Cost of sales [Member]
Restructuring Cost and Reserve [Line Items]
Severance and other restructuring costs	5,300,000	1,900,000	13,300,000	5,000,000
Selling, general and administrative expenses [Member]
Restructuring Cost and Reserve [Line Items]
Severance and other restructuring costs	2,600,000	1,600,000	32,600,000	3,200,000
Research and development [Member]
Restructuring Cost and Reserve [Line Items]
Severance and other restructuring costs	$ 1,300,000	$ 300,000	$ 2,900,000	$ 1,300,000