Share-Based Compensation (Schedule of Total Share-Based Compensation Expense by Type of Award) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation	$ 24	$ 25	$ 64	$ 73
Restricted Share Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation	20	18	56	53
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation	7	4	17	14
Performance Share Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation	$ (4)	$ 3	$ (9)	$ 6