Stock-Based Compensation Plans (Stock Appreciation Rights Activity) (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Sep. 30, 2011 years
Stock-Settled Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding at September 30, 2010	2,737,553
Weighted Average Exercise Price Per Share, Outstanding beginning balance	$ 55.58
Stock Appreciation Rights, Granted	35,000
Weighted Average Exercise Price Per Share, Granted	$ 62.41
Stock Appreciation Rights, Exercised	(128,206)
Weighted Average Exercise Price, Exercised	$ 51.85
Stock Appreciation Rights, Forfeited	(53,001)
Weighted Average Exercise Price Per Share, Forfeited	$ 59.85
Outstanding at September 30, 2011	2,591,346
Weighted Average Exercise Price Per Share, Outstanding ending balance	$ 55.77
Weighted Average Remaining Contractual Term, Outstanding, years	7.0
Aggregate Intrinsic Value, Outstanding	$ 54.3
Stock Appreciation Rights, Vested and expected to vest	2,559,441
Weighted Average Exercise Price Per Share, Vested and expected to vest	$ 55.72
Weighted Average Remaining Contractual Term, Vested and expected to vest, years	7.0
Aggregate Intrinsic Value, Vested and expected to vest	53.7
Shares Under Option, Exercisable	1,172,833
Weighted Average Exercise Price Per Share, Exercisable	$ 51.81
Weighted Average Remaining Contractual Term, Exercisable	5.5
Aggregate Intrinsic Value, Exercisable	29.2
Cash-Settled Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding at September 30, 2010	51,000
Weighted Average Exercise Price Per Share, Outstanding beginning balance	$ 57.45
Stock Appreciation Rights, Exercised	(1,500)
Weighted Average Exercise Price, Exercised	$ 57.45
Stock Appreciation Rights, Forfeited	(2,000)
Weighted Average Exercise Price Per Share, Forfeited	$ 57.45
Outstanding at September 30, 2011	47,500
Weighted Average Exercise Price Per Share, Outstanding ending balance	$ 57.45
Weighted Average Remaining Contractual Term, Outstanding, years	8.6
Aggregate Intrinsic Value, Outstanding	914.9
Stock Appreciation Rights, Vested and expected to vest	44,965
Weighted Average Exercise Price Per Share, Vested and expected to vest	$ 57.45
Weighted Average Remaining Contractual Term, Vested and expected to vest, years	8.6
Aggregate Intrinsic Value, Vested and expected to vest	866.0
Shares Under Option, Exercisable	2,000
Weighted Average Exercise Price Per Share, Exercisable	$ 57.45
Weighted Average Remaining Contractual Term, Exercisable	0.2
Aggregate Intrinsic Value, Exercisable	$ 38.5