Share-Based Compensation (Summary of Deferred Stock Units Activity) (Details) - Deferred Stock Units shares in Thousands	12 Months Ended
	Sep. 30, 2017 $ / shares shares
Shares
Outstanding, beginning (shares) | shares	1,001
Equitable adjustment upon separation (shares) | shares	65
Surrender upon separation (shares) | shares	(89)
Granted (shares) | shares	283
Paid out (shares) | shares	(235)
Forfeited/adjustments (shares) | shares	(50)
Outstanding, ending (shares) | shares	975
Weighted Average Grant Date Fair Value
Outstanding, beginning (in dollars per share) | $ / shares	$ 119.44
Equitable adjustment upon separation (in dollars per share) | $ / shares	0.00
Surrender upon separation (in dollars per share) | $ / shares	132.88
Granted (in dollars per share) | $ / shares	148.89
Paid out (in dollars per share) | $ / shares	83.65
Forfeited/adjustments (in dollars per share) | $ / shares	121.99
Outstanding, ending (in dollars per share) | $ / shares	$ 127.29