Employee Benefit Plans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 28, 2014	Mar. 29, 2013
U.S. Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 14	$ 16
Interest cost	140	130
Expected return on assets	(186)	(156)
Recognized actuarial net loss	2	73
Total defined benefit net periodic pension cost	(30)	63
Multiemployer benefit expense	258	252
Net periodic pension cost	228	315
UK Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	552	531
Expected return on assets	(466)	(414)
Recognized actuarial net loss	18	11
Total defined benefit net periodic pension cost	104	128
Multiemployer benefit expense	0	0
Net periodic pension cost	$ 104	$ 128