Employee Benefit Plans (Summary of Participants) (Details)	Dec. 25, 2015 employees
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Active Employees	5,234
Retirees and Beneficiaries	11,777
Other	3,781	[1]
Total	20,792
Post-retirement Medical Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Active Employees	1,212
Retirees and Beneficiaries	12,957
Other	69	[1]
Total	14,238

[1] For pension plans, the other category consists mostly of terminated but vested former employees. For post-retirement plans, the other category consists of employees on long-term disability that have not yet retired.