Net Periodic Benefit Cost - Defined Benefit Pension Plans (Details) (Pension plans, defined benefit [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended
	Apr. 04, 2015	Mar. 29, 2014
Pension plans, defined benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service costs--increase in benefit obligation earned	$ 21	$ 13
Interest cost on projected benefit obligation	379	404
Expected return on plan assets	(405)	(498)
Amortization of net actuarial loss	387	177
Amortization of prior service cost	3	3
Net pension cost of defined benefit pension plans	$ 385	$ 99