Discontinued Operations - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended				0 Months Ended
	Mar. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2010	Dec. 31, 2012
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain/(Loss) on disposal of discontinued operations, net of tax	$ (562,000)	$ (562,000)		$ 134,480,000
Income tax expense for discontinued operations		(900,000)	1,400,000	78,700,000
Receivable, net		379,777,000	304,204,000
Partial settlement received from escrow		4,200,000
Income/(Loss) from Discontinued Operations, before tax				25,459,000
Thermax and Raydex [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Amount received in cash from the sales of business units				265,600,000
Gain/(Loss) on disposal of discontinued operations, before tax		(900,000)		211,600,000
Gain/(Loss) on disposal of discontinued operations, net of tax		(600,000)		124,700,000
Income tax expense for discontinued operations			(1,400,000)
Income/(Loss) from Discontinued Operations, before tax				21,479,000
Trapeze [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Amount received in cash from the sales of business units					136,900,000
Gain/(Loss) on disposal of discontinued operations, before tax					88,300,000
Gain/(Loss) on disposal of discontinued operations, net of tax		600,000			44,800,000
Sale price for business					152,100,000
Amount in escrow as partial security for Company's indemnity obligations under transaction's purchase and sale agreement					15,200,000
Receivable, net		3,800,000
Communications cable operation in Phoenix, Arizona [Member] | Uncertain tax positions liability [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain/(Loss) on disposal of discontinued operations, net of tax						14,100,000
Communications cable operation in Phoenix, Arizona [Member] | Uncertain tax positions liability [Member] | Reversal of accrued interest and penalties [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income/(Loss) from Discontinued Operations, before tax						4,000,000
Income/(Loss) from Discontinued Operations, net of tax						$ 2,600,000