Summary Of Significant Accounting Policies (Schedule Of Movement Of Warranty Reserves) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 27, 2015	Sep. 28, 2014
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
Balance at beginning of year	$ 4,379	$ 4,521
Accruals for warranties issued, net	1,684	3,054
Settlements made	(2,364)	(2,717)
Foreign currency translation adjustment	(191)	(184)
Balance at end of period	$ 3,508	$ 4,674