Pension And Other Post Retirement Benefits Net Periodic Benefit Cost For Other Post Retirement Benefit Plan (Details) - Other Post Retirement Benefits - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 28, 2014	Sep. 30, 2015	Sep. 28, 2014
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 27	$ 61	$ 81	$ 297
Interest cost	120	260	362	1,359
Recognized actuarial gain	6	(3)	18	(22)
Net periodic benefit credit	$ 153	$ 318	$ 461	$ 1,634