Pension and Postretirement Benefit Plans Net Periodic Benefit (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 27, 2014	Sep. 28, 2013	Sep. 27, 2014	Sep. 28, 2013	Dec. 28, 2013
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plans, Estimated Future Employer Contributions in Next Fiscal Year			$ 5,000,000
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	0	(63,000)	0	(188,000)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(37,146,000)		(37,146,000)		(8,106,000)
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax	15,800,000		15,800,000
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	850,000	844,000	2,598,000	2,523,000
Interest cost	3,176,000	1,387,000	8,097,000	4,157,000
Expected return on plan assets	(4,016,000)	(1,880,000)	(10,256,000)	(5,628,000)
Curtailment / settlement (gain) loss	0	0	0	0
Defined Benefit Plan, Actuarial Gain (Loss)	(4,000)	87,000	(12,000)	262,000
Transition costs and other	0	0	0	0
Net periodic benefit cost	6,000	438,000	427,000
United States Pension Plan of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost				1,314,000
Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	9,000	14,000	27,000	44,000
Interest cost	94,000	45,000	281,000	137,000
Curtailment / settlement (gain) loss	0	0	0	0
Defined Benefit Plan, Actuarial Gain (Loss)	5,000	9,000	15,000	27,000
Transition costs and other	0	0	0	0
Net periodic benefit cost	108,000	68,000
United States Postretirement Benefit Plan of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost			323,000	208,000
Maximum
Defined Benefit Plan Disclosure [Line Items]
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	$ 100,000	$ (100,000)	$ 100,000	$ 300,000