Acquisitions and Other Investments (Details) (USD $)	3 Months Ended									12 Months Ended			3 Months Ended	12 Months Ended		12 Months Ended						0 Months Ended	12 Months Ended		12 Months Ended									12 Months Ended
	Dec. 31, 2012	Sep. 29, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Oct. 01, 2011	Jul. 02, 2011	Apr. 02, 2011	Mar. 31, 2010	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Jul. 02, 2011 TV One [Member]	Dec. 31, 2012 TV One [Member]	Apr. 28, 2011 TV One [Member]	Dec. 31, 2012 Ergotron, Inc [Member]	Dec. 31, 2011 Ergotron, Inc [Member]	Dec. 31, 2010 Ergotron, Inc [Member]	Dec. 17, 2010 Ergotron, Inc [Member]	Jul. 06, 2010 Linear LLC [Member]	Mar. 21, 2011 Huntair Arabia [Member]	Mar. 21, 2011 Co-venturer [Member] Notes Payable, Other Payables [Member]	Dec. 31, 2010 SG&A [Member] Ergotron, Inc [Member]	Jul. 06, 2010 Unsecured Subordinated Note, 4 Percent [Member] Senior Subordinated Notes [Member] Linear LLC [Member]	Dec. 31, 2012 TECH [Member]		Dec. 31, 2011 TECH [Member]		Dec. 31, 2010 TECH [Member]		Dec. 31, 2012 Layaway Sale [Member] TECH [Member]	Dec. 31, 2011 Layaway Sale [Member] TECH [Member]	Jun. 30, 2013 Scenario, Forecast [Member] Subsequent Event [Member] 2GIG Technologies, Inc. [Member]	Dec. 31, 2010 Fair Value Adjustment [Member] Ergotron, Inc [Member]	Dec. 31, 2010 Fair Value Adjustment to Inventory [Member] Ergotron, Inc [Member]	Dec. 31, 2010 Acquisition-related Costs [Member] Ergotron, Inc [Member]
Business Acquisition [Line Items]
Percentage of voting interests acquired															100.00%				100.00%	100.00%
Purchase price															$ 25,100,000
Cash acquired															900,000
Fees and expenses													800,000					2,200,000					2,200,000
Net sales	505,400,000	557,400,000	615,700,000	522,800,000	535,200,000	551,800,000	564,900,000	488,600,000		2,201,300,000	2,140,500,000	1,899,300,000		6,100,000											422,700,000		455,200,000		396,900,000
Operating earnings (loss)	15,200,000	33,800,000	53,700,000	24,900,000	26,400,000	14,000,000	20,800,000	1,900,000		127,600,000	63,100,000	70,600,000		0											14,200,000	[1]	35,400,000	[1]	10,700,000	[1]
Depreciation and amortization														400,000
Equity method investment, ownership percentage																					49.00%
Equity method investment, aggregate cost																					5,300,000
Maturity period																						10 years
Debt face amount																						5,300,000		1,200,000.0
Consideration transferred	2,600,000				30,900,000					2,600,000	30,900,000	285,200,000							299,600,000	9,100,000													135,000,000
Cost of acquired entity, cash paid																			298,200,000	7,900,000
Net cash paid for businesses acquired										2,600,000	30,900,000	285,200,000				2,600,000	5,800,000
Preexisting relationship, income tax refunds payable																1,400,000
Pro forma revenue																		2,100,000,000
Pro forma net income (loss)																		(21,400,000)
Pro forma earnings per share, basic																		$ (1.43)
Pro forma earnings per share, diluted																		$ (1.43)
Depreciation and amortization expense										83,700,000	93,900,000	91,700,000																						18,600,000	7,300,000
Debt interest expense																																				25,300,000
Interest rate																								4.00%
Payments for previous acquisition									1,300,000
Recognition of deferred revenue																															$ 63,100,000	$ 98,100,000

[1] For 2012, includes approximately $6.1 million of costs and expenses related to inventory reserves and one time termination benefits in conjunction with combining certain subsidiaries within the segment and a charge of approximately $3.7 million relating to the decision to discontinue development of a certain new product within the segment. In 2011, includes approximately $1.2 million of severance and other charges relating to exit and disposal activities and approximately $4.9 million of additional warranty expense related to a certain customer. In 2010, includes approximately $4.5 million of severance and other charges related to the closure of certain facilities and a gain of approximately $3.0 million related to the reversal of a loss contingency reserve that was previously provided in 2009 related to one of the Company's subsidiaries.