Capital Stock (Common Stock) (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011	Sep. 15, 2011 Maximum [Member]
Capital Stock [Abstract]
Common stock, authorized shares	300,000,000
Common stock, par value	$ 1	$ 1
Common stock, issued shares	249,455,584	249,455,584
Common stock, shares outstanding	213,538,144	211,179,257	212,475,880	210,185,256
Equity, Class of Treasury Stock [Line Items]
Share repurchase program authorized amount					$ 1,000
Shares repurchased during period, shares	0	5,721,017	594,916
Cost of shares repurchased		461.6	53.1
Share repurchase authorization remaining, amount	$ 485.3