Retirement Plans (Schedule Of Future Cash Flows) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 27, 2015	Jul. 05, 2015
Defined Benefit Plan Disclosure [Line Items]
Minimum required contribution for retirement plans		$ 0
Defined Benefit Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Net year-to-date contributions		13,707
Postretirement Healthcare Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Net year-to-date contributions		$ 652
Scenario, Forecast [Member] | Defined Benefit Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plans, Estimated Future Employer Contributions in Current Fiscal Year	$ 11,000
Scenario, Forecast [Member] | Postretirement Healthcare Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plans, Estimated Future Employer Contributions in Current Fiscal Year	$ 600