Shareholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	6 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Class of Stock [Line Items]
Payments for Repurchase of Common Stock	$ 150	$ 600
Treasury Stock, Shares, Retired		37.0
Treasury Stock, Common, Value		$ (2,500)
Common Stock, Shares, Outstanding		302
Retained earnings		$ 2,200
Treasury Shares
Class of Stock [Line Items]
Treasury shares acquired (using cost method), shares	2.2
Treasury shares acquired, average price per share (in usd per share)	$ 67.92	$ 74.08