Retirement Plans - (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 29, 2014	Mar. 30, 2013
Domestic Plans
Net periodic benefit cost:
Service cost	$ 322	$ 267
Interest cost	788	721
Expected return on plan assets	(1,018)	(887)
Amortization of unrecognized:
Prior service cost	3	0
Cumulative actuarial net loss	0	49
Net periodic benefit cost	95	150
Foreign Plans
Net periodic benefit cost:
Service cost	591	717
Interest cost	903	962
Expected return on plan assets	(1,069)	(997)
Amortization of unrecognized:
Prior service cost	5	5
Cumulative actuarial net loss	14	133
Net periodic benefit cost	444	820
OPEB Plans
Net periodic benefit cost:
Service cost	3	4
Interest cost	49	50
Expected return on plan assets	0	0
Amortization of unrecognized:
Prior service cost	(2)	0
Cumulative actuarial net loss	(11)	2
Net periodic benefit cost	$ 39	$ 56