Operating Segments - Operating Segment Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 29, 2015	Mar. 30, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Segment Revenues	$ 546,957	$ 487,690
Segment depreciation and amortization	38,045	21,238
Segment assets	3,460,947		3,262,827
Reportable Segment [Member]
Segment Reporting Information [Line Items]
Segment Revenues	569,451	488,307
Affiliate revenues	2,313	3,633
Segment EBITDA	88,274	73,616
Segment depreciation and amortization	38,045	21,238
Segment assets	991,410	852,387
Reportable Segment [Member] | Broadcast Solutions [Member]
Segment Reporting Information [Line Items]
Segment Revenues	213,586	166,485
Affiliate revenues	341	199
Segment EBITDA	29,232	26,171
Segment depreciation and amortization	16,905	13,400
Segment assets	418,175	292,690
Reportable Segment [Member] | Enterprise Connectivity Solutions [Member]
Segment Reporting Information [Line Items]
Segment Revenues	104,695	108,394
Affiliate revenues	1,620	2,076
Segment EBITDA	13,881	14,175
Segment depreciation and amortization	3,140	3,868
Segment assets	210,120	228,401
Reportable Segment [Member] | Industrial Connectivity Solutions [Member]
Segment Reporting Information [Line Items]
Segment Revenues	152,972	159,318
Affiliate revenues	323	1,356
Segment EBITDA	24,173	23,682
Segment depreciation and amortization	3,674	2,649
Segment assets	257,059	270,295
Reportable Segment [Member] | Industrial IT Solutions [Member]
Segment Reporting Information [Line Items]
Segment Revenues	61,073	54,110
Affiliate revenues	21	2
Segment EBITDA	11,087	9,588
Segment depreciation and amortization	1,969	1,321
Segment assets	62,559	61,001
Reportable Segment [Member] | Network Security Solutions [Member]
Segment Reporting Information [Line Items]
Segment Revenues	37,125
Affiliate revenues	8
Segment EBITDA	9,901
Segment depreciation and amortization	12,357
Segment assets	$ 43,497