Stock-Based Compensation (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Sep. 30, 2011 Plan Business Segment Entity Person	Sep. 30, 2010	Sep. 30, 2009
Stock-Based Compensation (Textuals)
Number of share-based compensation plans	3
Compensation cost charged against income from share-based compensation plans	$ 47	$ 52	$ 27
Total income tax benefit recognized for share-based compensation arrangements	19	21	11
Stock Option [Member]
Assumptions used in Black-Scholes option valuation model
Expected life (years), Minimum	4.5	4.3	4.2
Expected life (years), Maximum	6.0	5.0	4.5
Risk-free interest rate, Minimum	1.10%	1.91%	2.57%
Risk-free interest rate, Maximum	1.58%	2.20%	2.68%
Expected volatility of the Company's stock	38.00%	40.00%	28.00%
Expected dividend yield on the Company's stock	1.74%	1.73%	1.52%
Summary of stock option activity
Outstanding, September 30, 2010, Weighted Average Option Price	$ 24.17
Outstanding, September 30, 2010, Shares Subject to Option	35,158,109
Granted, Weighted Average Option Price	$ 30.64
Granted, Shares Subject to Option	4,994,156
Exercised, Weighted Average Option Price	$ 19.15
Exercised, Shares Subject to Option	(5,522,620)
Forfeited or expired, Weighted Average Option Price	$ 29.17
Forfeited or expired, Shares Subject to Option	(405,633)
Outstanding, September 30, 2011, Weighted Average Option Price	$ 25.87	$ 24.17
Outstanding, September 30, 2011, Shares Subject to Option	34,224,012	35,158,109
Outstanding, September 30, 2011, Weighted Average Remaining Contractual Life (years)	5.7
Outstanding, September 30, 2011, Aggregate Intrinsic Value	91
Exercisable, September 30, 2011, Weighted Average Option Price	$ 24.79
Exercisable, September 30, 2011, Shares Subject to Option	22,401,363
Exercisable, September 30, 2011, Weighted Average Remaining Contractual Life (years)	4.3
Exercisable, September 30, 2011, Aggregate Intrinsic Value	83
Stock-Based Compensation (Textuals)
Number of shares of new common stock authorized under Company's 2007 Stock Option	41,000,000
Vesting period	2 to 3 years
Expiration period for stock options	10 years
Common stock available to be granted	20,000,000
Weighted-average grant-date fair value of options granted	$ 9.09	$ 7.70	$ 6.68
Total intrinsic value of options exercised	101	33	4
Cash received from exercise of stock options granted	105	52	8
Tax benefit from the exercise of stock options, which is recorded in capital in excess of par	30	7	1
Total unrecognized compensation cost related to nonvested share-based compensation arrangements granted	31
Weighted average period over which unrecognized compensation cost is expected to be recognized	0.8
Stock Appreciation Rights [Member]
Assumptions used in Black-Scholes option valuation model
Expected life (years), Minimum	0.5
Expected life (years), Maximum	5.2
Risk-free interest rate, Minimum	0.06%
Risk-free interest rate, Maximum	1.01%
Expected volatility of the Company's stock	38.00%
Expected dividend yield on the Company's stock	1.80%
Summary of SAR activity
Outstanding, September 30, 2010, Weighted Average SAR Price	$ 25.23
Outstanding, September 30, 2010, Shares Subject to SAR	3,237,113
Granted, Weighted Average SAR Price	$ 30.54
Granted, Shares Subject to SAR	585,190
Exercised, Weighted Average SAR Price	$ 22.91
Exercised, Shares Subject to SAR	(290,973)
Forfeited or expired, Weighted Average SAR Price	$ 29.28
Forfeited or expired, Shares Subject to SAR	(67,355)
Outstanding, September 30, 2011, Weighted Average SAR Price	$ 26.24	$ 25.23
Outstanding, September 30, 2011, Shares Subject to SAR	3,463,975	3,237,113
Outstanding, September 30, 2011, Weighted Average Remaining Contractual Life (years)	6.0
Outstanding, September 30, 2011, Aggregate Intrinsic Value	8
Exercisable, September 30, 2011, Weighted Average SAR Price	$ 25.16
Exercisable, September 30, 2010, Shares Subject to SAR	2,032,304
Exercisable, September 30, 2011, Weighted Average Remaining Contractual Life (years)	4.4
Exercisable, September 30, 2011, Aggregate Intrinsic Value	7
Stock-Based Compensation (Textuals)
Payments towards exercise of SARs granted	4	3	2
Nonvested Restricted Stock Awards [Member]
Summary of nonvested restricted stock awards
Nonvested, September 30, 2010, Weighted Average Price	$ 31.60
Nonvested, September 30, 2010, Shares/Units Subject to Restriction	765,455
Granted, Weighted Average Price	$ 35.02
Granted, Shares/Units Subject to Restriction	331,700
Vested, Weighted Average Price	$ 25.57
Vested, Shares/Units Subject to Restriction	(32,750)
Nonvested, September 30, 2011, Weighted Average Price	$ 32.85
Nonvested, September 30, 2011, Shares/Units Subject to Restriction	1,064,405
Stock-Based Compensation (Textuals)
Total unrecognized compensation cost related to nonvested share-based compensation arrangements granted	$ 11
Weighted average period over which unrecognized compensation cost is expected to be recognized	1.2
Vesting rights for nonvested restricted stock awards	50% after 2 years and 50% after 4 years