Share-Based Compensation (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2012	Mar. 31, 2011
Share-Based Compensation (Textual) [Abstract]
Share-based Compensation expense, recognized	$ 10.9	$ 10.1	$ 22.3	$ 19.2
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period			1,383	1,708
Share-based Compensation Arrangement by Share-based Payment Award Options, Grants in Period Weighted Average Grant Date Fair Value			$ 23.51	$ 21.28
Performance shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Grants in Period			93	77
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 101.57	$ 87.00
Restricted stock and restricted stock units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Grants in Period			81	60
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 73.87	$ 72.30
Unrestricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Grants in Period			12	11
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 61.97	$ 69.79