Employee Benefits - Contributions to Employee Benefit Plans (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jul. 04, 2015	Jun. 28, 2014	Jul. 04, 2015	Jun. 28, 2014	Jan. 03, 2015
Defined Benefit Plan Disclosure [Line Items]
Employer contributions to employee benefit plans	$ 5	$ 9	$ 17	$ 37	$ 53
Total current year projected employer contributions			55
Pension
Defined Benefit Plan Disclosure [Line Items]
Employer contributions to employee benefit plans	1	5	10	29	37
Total current year projected employer contributions			39
Nonpension postretirement
Defined Benefit Plan Disclosure [Line Items]
Employer contributions to employee benefit plans	$ 4	$ 4	7	$ 8	$ 16
Total current year projected employer contributions			$ 16