Restructuring and Employee Severance (Activity Related to Restructuring and Employee Severance Costs) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Restructuring Cost and Reserve [Line Items]
Employee-related costs	$ 12	$ 15	$ 41	$ 19
Facility Exit and Other Costs	0	6	3	134
Total restructuring-related costs	$ 12	$ 21	$ 44	$ 153