Stock Compensation Plans (Details) - USD ($)		12 Months Ended
		Aug. 31, 2015	Aug. 31, 2014	Aug. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total shares authorized under Omnibus Plan (in shares)		60,400,000
Weighted-Average Grant-Date Fair Value [Roll Forward]
Number of options that may be granted under this plan (in shares)		94,000,000
Percentage of the fair market value that the plan permits eligible employees to purchase common stock		90.00%
Number of shares available for grant (in shares)		14,000,000
Value of shares granted to each directors		$ 175,000	$ 175,000	$ 170,000
Number of shares each nonemployee director was granted (in shares)		2,725	2,892	4,789
Share-based compensation expense		$ 109,000,000	$ 114,000,000	$ 104,000,000
Stock Options [Member]
Black-Scholes Option Pricing Model with Weighted-average Assumptions [Abstract]
Risk-free interest rate	[1]	1.97%	1.98%	1.15%
Average life of option	[2]	6 years 7 months 6 days	6 years 10 months 24 days	7 years
Volatility	[3]	25.58%	26.27%	24.94%
Dividend yield	[4]	1.79%	2.48%	2.44%
Weighted-average grant-date fair value (in dollars per share)		$ 14.62	$ 12.88	$ 6.75
Weighted-Average Grant-Date Fair Value [Roll Forward]
Intrinsic value for options exercised		$ 423,000,000	$ 346,000,000	$ 159,000,000
Fair value of options vested		54,000,000	58,000,000	51,000,000
Cash received from the exercise of options		352,000,000	490,000,000
Tax benefit from exercise of stock options		159,000,000	130,000,000
Share-based compensation expense		24,000,000	52,000,000	51,000,000
Restricted Stock Units [Member]
Weighted-Average Grant-Date Fair Value [Roll Forward]
Share-based compensation expense		68,000,000	48,000,000	33,000,000
Performance Shares [Member]
Weighted-Average Grant-Date Fair Value [Roll Forward]
Share-based compensation expense		11,000,000	8,000,000	15,000,000
Other [Member]
Weighted-Average Grant-Date Fair Value [Roll Forward]
Share-based compensation expense		$ 6,000,000	$ 6,000,000	$ 5,000,000
Omnibus Plan [Member]
Stock Options Authorized and Available for Future Grant [Roll Forward]
Outstanding shares at beginning of period (in shares)		48,352,242
Newly authorized options (in shares)		0
Granted (in shares)		(8,649,296)
Cancellation and forfeitures (in shares)		5,059,061
Plan termination (in shares)		1,409,063
Outstanding shares at end of period (in shares)		46,171,070	48,352,242
Outstanding Shares [Roll Forward]
Outstanding shares at beginning of period (in shares)		48,352,242
Granted (in shares)		(8,649,296)
Forfeited (in shares)		(5,059,061)
Outstanding shares at end of period (in shares)		46,171,070	48,352,242
Omnibus Plan [Member] | Stock Options [Member]
Outstanding Stock Options [Roll Forward]
Outstanding at beginning of period (in shares)		31,916,824
Granted (in shares)		4,119,972
Exercised (in shares)		(10,007,975)
Expired/Forfeited (in shares)		(3,754,248)
Outstanding at end of period (in shares)		22,274,573	31,916,824
Vested or expected to vest at end of period (in shares)		21,879,917
Exercisable at end of period (in shares)		8,825,638
Weighted Average Exercise Price [Abstract]
Outstanding at beginning of period (in dollars per share)		$ 39.28
Granted (in dollars per share)		64.19
Exercised (in dollars per share)		35.22
Expired/Forfeited (in dollars per share)		53.72
Outstanding at end of period (in dollars per share)		43.52	$ 39.28
Vested or expected to vest at end of period (in dollars per share)		43.20
Exercisable at end of period (in dollars per share)		$ 32.42
Weighted Average Remaining Contractual Terms [Abstract]
Outstanding		6 years 3 months 14 days	6 years 4 months 24 days
Vested or expected to vest at end of period		6 years 3 months
Exercisable at end of period		4 years 11 days
Aggregate Intrinsic Value [Abstract]
Outstanding at beginning of period		$ 674,000,000
Outstanding at end of period		959,000,000	$ 674,000,000
Vested or expected to vest at end of period		948,000,000
Exercisable at end of period		$ 478,000,000
Omnibus Plan [Member] | Restricted Stock Units [Member]
Stock Options Authorized and Available for Future Grant [Roll Forward]
Outstanding shares at beginning of period (in shares)		3,280,067
Granted (in shares)		1,157,312
Cancellation and forfeitures (in shares)		636,244
Outstanding shares at end of period (in shares)		3,334,452	3,280,067
Outstanding Shares [Roll Forward]
Outstanding shares at beginning of period (in shares)		3,280,067
Granted (in shares)		1,157,312
Dividends (in shares)		64,796
Forfeited (in shares)		(636,244)
Vested (in shares)		(531,479)
Outstanding shares at end of period (in shares)		3,334,452	3,280,067
Weighted-Average Grant-Date Fair Value [Roll Forward]
Outstanding at beginning of period (in dollars per share)		$ 45.40
Granted (in dollars per share)		66.26
Dividends (in dollars per share)		0
Forfeited (in dollars per share)		52.68
Vested (in dollars per share)		52.29
Outstanding at end of period (in dollars per share)		$ 50.85	$ 45.40
Omnibus Plan [Member] | Performance Shares [Member]
Stock Options Authorized and Available for Future Grant [Roll Forward]
Outstanding shares at beginning of period (in shares)		2,063,132
Granted (in shares)		483,174
Cancellation and forfeitures (in shares)		444,961
Outstanding shares at end of period (in shares)		1,445,780	2,063,132
Outstanding Shares [Roll Forward]
Outstanding shares at beginning of period (in shares)		2,063,132
Granted (in shares)		483,174
Performance adjustment (in shares)	[5]	(615,445)
Forfeited (in shares)		(444,961)
Vested (in shares)		(40,120)
Outstanding shares at end of period (in shares)		1,445,780	2,063,132
Weighted-Average Grant-Date Fair Value [Roll Forward]
Outstanding at beginning of period (in dollars per share)		$ 44.85
Granted (in dollars per share)		65.31
Performance adjustment (in dollars per share)	[5]	35.30
Forfeited (in dollars per share)		55.00
Vested (in dollars per share)		44.00
Outstanding at end of period (in dollars per share)		$ 50.78	$ 44.85

[1] Represents the U.S. Treasury security rates for the expected term of the option.

[2] Represents the period of time that options granted are expected to be outstanding. The Company analyzed separate groups of employees with similar exercise behavior to determine the expected term.

[3] Volatility was based on historical and implied volatility of the Company's common stock.

[4] Represents the Company's forecasted cash dividend for the expected term.

[5] Represents the adjustment to previously granted shares based on performance criteria.