Derivatives and Hedging Activities - Effect of Non-designated Contracts (Details 5) - Foreign Exchange Forward Contract [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 27, 2015	Sep. 28, 2014
Effect of nondesignated derivative contracts
Loss on foreign exchange forward contracts including forward point income	$ (218)	$ (5,869)	$ (293)	$ (2,594)
Gain (loss) from revaluation of foreign currency exposures hedged by foreign exchange forward contracts	(288)	4,676	(4,461)	1,926
Total effect of non-designated derivative contracts	$ (506)	$ (1,193)	$ (4,754)	$ (668)