Postretirement Benefit Plans - Components of Periodic Benefit Costs (Details) - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2016	Oct. 02, 2015
Net periodic benefit income
Service cost	$ 15	$ 19
Interest cost	48	66
Expected return on plan assets	(89)	(91)
Amortization of net actuarial loss	0	2
Amortization of prior service cost	0	(3)
Total net periodic benefit income	(26)	(7)
Pension
Net periodic benefit income
Service cost	15	18
Interest cost	46	62
Expected return on plan assets	(85)	(86)
Amortization of net actuarial loss	0	0
Amortization of prior service cost	0	0
Total net periodic benefit income	(24)	(6)
Other Benefits
Net periodic benefit income
Service cost	0	1
Interest cost	2	4
Expected return on plan assets	(4)	(5)
Amortization of net actuarial loss	0	2
Amortization of prior service cost	0	(3)
Total net periodic benefit income	$ (2)	$ (1)