Cost in Excess of Net Assets of Companies Acquired - Intangibles (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended			6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended							6 Months Ended
	Jun. 28, 2014	Jun. 29, 2013	Jun. 28, 2014	Jun. 29, 2013	Dec. 31, 2013	Jun. 28, 2014 Customer Relationships [Member]	Dec. 31, 2013 Customer Relationships [Member]	Jun. 28, 2014 Developed Technology [Member]	Dec. 31, 2013 Developed Technology [Member]	Jun. 28, 2014 Other Intangible Assets [Member]		Dec. 31, 2013 Other Intangible Assets [Member]		Jun. 28, 2014 Trade Names [Member]	Dec. 31, 2013 Trade Names [Member]	Jun. 28, 2014 Minimum [Member] Other Intangible Assets [Member]	Jun. 28, 2014 Maximum [Member] Other Intangible Assets [Member]
Finite And Indefinite Lived Intangible Assets [Line Items]
Weighted-Average Life						10 years	10 years	5 years	5 years
Gross Carrying Amount	$ 581,144		$ 581,144		$ 567,478	$ 389,362	$ 374,244	$ 9,877	$ 9,625	$ 2,905	[1]	$ 4,609	[1]	$ 179,000	$ 179,000
Accumulated Amortization	(161,862)		(161,862)		(141,409)	(154,920)	(134,817)	(5,152)	(4,051)	(1,790)	[1]	(2,541)	[1]	0	0
Net	419,282		419,282		426,069	234,442	239,427	4,725	5,574	1,115	[1]	2,068	[1]	179,000	179,000
Finite-Lived Intangible Assets, Useful Life																1 year	3 years
Amortization of Intangible Assets	10,870	8,869	21,817	17,826
Amortization of intangible assets, net of tax	$ 8,867	$ 7,029	$ 17,774	$ 14,145
Amortization of intangible assets, per share basic	$ 0.09	$ 0.07	$ 0.18	$ 0.14
Amortization of intangible assets, per share diluted	$ 0.09	$ 0.07	$ 0.18	$ 0.13

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