Goodwill and Intangible Assets, Net (Changes in the Carrying Amount of Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 28, 2014	Dec. 29, 2013
Changes in the carrying amount of goodwill
Beginning balance	$ 2,143,120	$ 2,122,788
Foreign currency translation	(37,886)	15,167
Acquisitions, earn outs and other	178,843	5,165
Ending balance	2,284,077	2,143,120
Human Health [Member]
Changes in the carrying amount of goodwill
Beginning balance	1,648,332	1,632,487
Foreign currency translation	(29,145)	12,867
Acquisitions, earn outs and other	2,408	2,978
Ending balance	1,621,595	1,648,332
Environmental Health [Member]
Changes in the carrying amount of goodwill
Beginning balance	494,788	490,301
Foreign currency translation	(8,741)	2,300
Acquisitions, earn outs and other	176,435	2,187
Ending balance	$ 662,482	$ 494,788