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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value.

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Property, Plant and Equipment - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Proceeds from disposal of real estate	$ 1,884,000	$ 3,169,000	$ 9,575,000
Impairment loss recognized	0	0	29,800,000
Depreciation expense	43,700,000us-gaap_Depreciation	43,600,000us-gaap_Depreciation	35,100,000us-gaap_Depreciation
Property, Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Impairment loss recognized			10,600,000
Customer Relationships [Member]
Property, Plant and Equipment [Line Items]
Impairment loss recognized			6,800,000
Real Estate [Member]
Property, Plant and Equipment [Line Items]
Impairment losses			1,500,000
Manufacturing Equipment [Member]
Property, Plant and Equipment [Line Items]
Impairment losses			1,400,000
Other Property, Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Impairment losses			1,000,000
Trademarks [Member]
Property, Plant and Equipment [Line Items]
Impairment loss recognized			5,200,000
Broadcast Solutions [Member]
Property, Plant and Equipment [Line Items]
Proceeds from disposal of real estate	1,900,000	1,000,000
Gain (loss) recognized on the sale	0	(300,000)
Enterprise Connectivity Solutions [Member]
Property, Plant and Equipment [Line Items]
Proceeds from disposal of real estate		2,100,000	800,000
Gain (loss) recognized on the sale		0	0
Impairment losses			1,500,000
All Other [Member]
Property, Plant and Equipment [Line Items]
Proceeds from disposal of real estate			40,000,000
Gain (loss) on the sale of assets		1,300,000	(29,800,000)
Industrial Connectivity Solutions [Member]
Property, Plant and Equipment [Line Items]
Proceeds from disposal of real estate			8,600,000
Gain (loss) recognized on the sale			0
Impairment losses			$ 2,400,000