Goodwill and Intangible Assets, Net (Changes in the Carrying Amount of Goodwill) (Details) $ in Thousands	9 Months Ended
	Oct. 04, 2015 USD ($)
Changes in the carrying amount of goodwill
Balance at beginning of period	$ 2,284,077
Foreign currency translation	(42,575)
Goodwill, Acquisition, Earn Outs and Other Adjustments	12,441
Balance at end of period	2,253,943
Human Health [Member]
Changes in the carrying amount of goodwill
Balance at beginning of period	1,662,755
Foreign currency translation	(19,018)
Goodwill, Acquisition, Earn Outs and Other Adjustments	33
Balance at end of period	1,643,770
Environmental Health [Member]
Changes in the carrying amount of goodwill
Balance at beginning of period	621,322
Foreign currency translation	(23,557)
Goodwill, Acquisition, Earn Outs and Other Adjustments	12,408
Balance at end of period	$ 610,173