Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2015	Sep. 30, 2014
Statement of Financial Position [Abstract]
Common stock, par value (USD per share)	$ 1	$ 1
Common stock, shares authorized (shares)	640,000,000	640,000,000
Common stock, shares issued (shares)	332,662,160	332,662,160
Common stock in treasury, shares (shares)	121,966,516	140,770,158