Employee Benefit Plans - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 30, 2016	Dec. 25, 2015
Defined Benefit Plan Disclosure [Line Items]
Non-qualified Employer Contributions	$ 250,000,000
Significant expected contributions	0
Pension plan assets at fair value	2,539,000,000	$ 2,309,000,000
Change in Assumptions for Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Decrease in net periodic pension expense	$ 25,000,000
Equity
Defined Benefit Plan Disclosure [Line Items]
Investment committee equity target allocation percentage of pension assets	70.00%
Targeted allocation of total plan assets in domestic equity (as a percent)	42.00%
Targeted allocation of total plan assets in international equity (as a percent)	28.00%
Percentage within which the planned allocation is managed (as a percent)	3.00%
Pension plan assets at fair value	$ 1,806,000,000	1,626,000,000
Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Investment committee equity target allocation percentage of pension assets	30.00%
Pension plan assets at fair value	$ 665,000,000	$ 641,000,000