Pension And Other Post Retirement Benefits Net Periodic Benefit Cost For Pension Benefit Plan (Details) - Pension Plan - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 29, 2014	Jun. 30, 2015	Jun. 29, 2014
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 198	$ 105	$ 354	$ 231
Interest cost	20,531	20,594	40,908	41,055
Expected return on plans’ assets	(28,009)	(28,243)	(55,845)	(56,528)
Recognized actuarial loss (gain)	0	26	0	(80)
Net periodic benefit credit	$ (7,280)	$ (7,518)	$ (14,583)	$ (15,322)