Pension and Postretirement Benefit Plans Net Periodic Benefit (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 29, 2014	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plans, Estimated Future Employer Contributions in Next Fiscal Year	$ 3,400,000
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	0	0
Curtailment / settlement (gain) loss	0	0
Transition costs and other	91,000	1,000
Accumulated Other Comprehensive Income (Loss), Net of Tax	(87,842,000)		(59,164,000)
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	1,001,000	873,000
Interest cost	1,975,000	2,458,000
Expected return on plan assets	(2,686,000)	(3,118,000)
Curtailment / settlement (gain) loss	0	0
Defined Benefit Plan, Actuarial Gain (Loss)	98,000	(4,000)
Transition costs and other	(9,000)	0
Net periodic benefit cost	379,000	209,000
Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	2,000	9,000
Interest cost	44,000	93,000
Curtailment / settlement (gain) loss	0	0
Defined Benefit Plan, Actuarial Gain (Loss)	2,000	5,000
Transition costs and other	0	0
Net periodic benefit cost	48,000	107,000
Maximum
Defined Benefit Plan Disclosure [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (87,842,000)