Supplemental Information (Share Repurchase Program) (Narrative) (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended	3 Months Ended		6 Months Ended
	Sep. 15, 2011	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Supplemental Information [Line Items]
Share repurchase program authorized amount	$ 1,000
Shares repurchased during period, shares				5.7
Purchase of treasury shares		0	53.1	461.6	53.1
Share repurchase authorization remaining, amount				$ 485.3