Postretirement Benefit Plans - Components of Periodic Benefit Costs (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Dec. 30, 2016	Jan. 01, 2016	Dec. 30, 2016	Jan. 01, 2016
Net periodic benefit income
Service cost	$ 14	$ 22	$ 29	$ 41
Interest cost	48	64	96	130
Expected return on plan assets	(89)	(89)	(178)	(180)
Amortization of net actuarial loss	0	0	0	2
Amortization of prior service cost	0	(4)	0	(7)
Net periodic benefit income	(27)	(7)	(53)	(14)
Effect of curtailments or settlements	0	(121)	0	(121)
Total net periodic benefit income	(27)	(128)	(53)	(135)
Pension
Net periodic benefit income
Service cost	14	20	29	38
Interest cost	46	61	92	123
Expected return on plan assets	(85)	(85)	(170)	(171)
Amortization of net actuarial loss	0	0	0	0
Amortization of prior service cost	0	0	0	0
Net periodic benefit income	(25)	(4)	(49)	(10)
Effect of curtailments or settlements	0	0	0	0
Total net periodic benefit income	(25)	(4)	(49)	(10)
Other Benefits
Net periodic benefit income
Service cost	0	2	0	3
Interest cost	2	3	4	7
Expected return on plan assets	(4)	(4)	(8)	(9)
Amortization of net actuarial loss	0	0	0	2
Amortization of prior service cost	0	(4)	0	(7)
Net periodic benefit income	(2)	(3)	(4)	(4)
Effect of curtailments or settlements	0	(121)	0	(121)
Total net periodic benefit income	$ (2)	(124)	(4)	$ (125)
Net liability reduction for certain post-employment benefit plans		$ (101)	$ (101)