Cost in Excess of Net Assets of Companies Acquired and Intangible Assets, Net - Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended					3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended		3 Months Ended
	Mar. 31, 2012	Apr. 02, 2011	Dec. 31, 2011	Mar. 31, 2012 Trade Names [Member]	Dec. 31, 2011 Trade Names [Member]	Mar. 31, 2012 Customer Relationships [Member] Years	Dec. 31, 2011 Customer Relationships [Member] Years	Mar. 31, 2012 Patented Technology [Member] Years	Dec. 31, 2011 Patented Technology [Member] Years	Dec. 31, 2011 Procurement Agreement [Member] Years	Mar. 31, 2012 Other Intangible Assets [Member] Years		Dec. 31, 2011 Other Intangible Assets [Member]
Finite And Indefinite Lived Intangible Assets [Line Items]
Finite And Indefinite Lived Intangible Assets Gross	$ 505,245		$ 484,331	$ 179,000	$ 179,000	$ 300,939	$ 267,729	$ 15,759	$ 11,029	$ 12,000	$ 9,547	[1]	$ 14,573	[1]
Finite-Lived Intangible Assets, Accumulated Amortization	(84,517)		(91,568)	0	0	(77,182)	(69,762)	(1,135)	(693)	(11,400)	(6,200)	[1]	(9,713)	[1]
Intangible assets, net	420,728		392,763	179,000	179,000	223,757	197,967	14,624	10,336	600	3,347	[1]	4,860	[1]
Acquired Finite-lived Intangible Asset, Weighted Average Useful Life						11	11	6	6	5
Acquired Finite-lived Intangible Asset, Useful Life, Maximum											3
Acquired Finite-lived Intangible Asset, Useful Life, Minimum											1
Amortization of Intangible Assets	$ 9,671	$ 6,883

[1] (a) Consists of non-competition agreements and sales backlog with useful lives ranging from one to three years.