CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS (LOSS) - (Unaudited) (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 29, 2014	Jun. 30, 2013	Jun. 29, 2014	Jun. 30, 2013
Statement Of Income And Comprehensive Income [Abstract]
Translation adjustment, tax expense (benefit)	$ (228)	$ (71)	$ (299)	$ 463
Amortization of prior service cost included in net periodic pension costs, tax	0	59	0	118
Amortization of loss included in net periodic pension costs, tax	507	774	1,043	1,548
Settlements and curtailments included in net earnings, tax	66	0	66	0
Foreign exchange impact, tax expense (benefit)	(37)	(2)	(37)	72
Unrealized holding (loss)/ gain arising during period, tax expense (benefit)	(136)	298	(157)	312
Reclassification adjustments for losses included in net earnings, tax	$ 47	$ 31	$ 92	$ 61