Employee Benefit Plans - Summary of Participants (Details)	Jan. 01, 2016 employee
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Active Employees	4,823
Retirees and Beneficiaries	12,018
Other	3,853
Total	20,694
Post-retirement Medical Plan
Defined Benefit Plan Disclosure [Line Items]
Active Employees	1,139
Retirees and Beneficiaries	11,893
Other	54
Total	13,086