Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 02, 2016	Mar. 28, 2015
Pension Benefits [Member]
Components of net periodic benefit cost [Abstract]
Service cost	$ 195	$ 272
Interest cost	1,975	2,054
Expected return on plan assets	(2,466)	(2,654)
Amortization of net loss	774	714
Net periodic benefit (income) cost	478	386
Other Benefits [Member]
Components of net periodic benefit cost [Abstract]
Service cost	62	96
Interest cost	156	196
Amortization of prior service cost (credit)	(224)	2
Amortization of net loss	2	3
Net periodic benefit (income) cost	$ (4)	$ 297