Income Taxes (Details) (USD $)	3 Months Ended								12 Months Ended
	Aug. 31, 2011	May 31, 2011	Feb. 28, 2011	Nov. 30, 2010	Aug. 31, 2010	May 31, 2010	Feb. 28, 2010	Nov. 30, 2009	Aug. 31, 2011	Aug. 31, 2010	Aug. 31, 2009
Geographical sources of income from continuing operations [Abstract]
United States									$ 1,213,353,000	$ 1,227,794,000	$ 1,085,704,000
Foreign									(259,406,000)	(226,726,000)	(18,777,000)
Income from continuing operations before income taxes	228,558,000	343,110,000	(23,596,000)	405,875,000	140,597,000	299,842,000	170,216,000	390,413,000	953,947,000	1,001,068,000	1,066,927,000
Current:
Federal									350,640,000	458,375,000	377,911,000
State									11,372,000	131,284,000	93,350,000
Foreign									1,129,000	(218,000)	(1,025,000)
Total current									363,141,000	589,441,000	470,236,000
Deferred:
Federal									62,474,000	(106,834,000)	(8,667,000)
State									10,214,000	(7,574,000)	(4,872,000)
Foreign									(15,191,000)	(10,970,000)	23,000
Total deferred									57,497,000	(125,378,000)	(13,516,000)
Total provision for income taxes	44,622,000	130,385,000	76,052,000	169,579,000	122,628,000	122,390,000	69,064,000	149,981,000	420,638,000	464,063,000	456,720,000
Deferred tax assets:
Allowance for doubtful accounts	44,364,000				72,344,000				44,364,000	72,344,000
Deferred rent and tenant improvement allowances	25,198,000				28,921,000				25,198,000	28,921,000
Net operating loss carry-forward	10,718,000				17,629,000				10,718,000	17,629,000
Litigation charge	61,502,000				70,383,000				61,502,000	70,383,000
Share-based compensation	67,697,000				63,168,000				67,697,000	63,168,000
Other	59,001,000				73,821,000				59,001,000	73,821,000
Gross deferred tax assets	268,480,000				326,266,000				268,480,000	326,266,000
Valuation allowance	(10,446,000)				(14,645,000)				(10,446,000)	(14,645,000)
Deferred tax assets, net of valuation allowance	258,034,000				311,621,000				258,034,000	311,621,000
Deferred tax liabilities:
Fixed assets	57,314,000				39,276,000				57,314,000	39,276,000
Intangible assets	30,738,000				40,069,000				30,738,000	40,069,000
Other	1,296,000				5,531,000				1,296,000	5,531,000
Gross deferred tax liabilities	89,348,000				84,876,000				89,348,000	84,876,000
Net deferred income taxes	168,686,000				226,745,000				168,686,000	226,745,000
Unrecognized tax benefits rollforward [Abstract]
Beginning balance				166,048,000				84,861,000	166,048,000	84,861,000
Additions based on tax positions taken in the current year									4,503,000	99,590,000
Additions for tax positions taken in prior years									15,570,000	18,323,000
Settlement with tax authorities									(110,980,000)	(20,665,000)
Reductions for tax positions of prior years									(45,231,000)	(11,733,000)
Reductions due to lapse of applicable statute of limitations									(4,099,000)	(4,328,000)
Ending balance	25,811,000				166,048,000				25,811,000	166,048,000	84,861,000
Unrecognized assets in unrecognized tax benefits	1,200,000				44,400,000				1,200,000	44,400,000
Uncertain tax position interest and penalties expense									(1,700,000)	(10,400,000)	4,400,000
Uncertain tax position interest and penalties accrued	3,700,000				5,400,000				3,700,000	5,400,000
Unrecognized tax benefits that would impact tax rate	18,400,000								18,400,000
Effective income tax rate reconciliation [Abstract]
Statutory U.S. federal income tax rate									35.00%	35.00%	35.00%
State income taxes, net of federal benefit									1.80%	6.30%	5.10%
Non-deductible compensation, net									0.30%	(1.10%)	0.40%
Foreign taxes									0.80%	1.10%	0.60%
Litigation charge									(1.00%)	0.00%	0.90%
Goodwill impairments									7.40%	5.80%	0.00%
Meritus closure									(0.80%)	0.00%	0.00%
Other, net									0.60%	(0.70%)	0.80%
Effective income tax rate									44.10%	46.40%	42.80%
United States [Member]
Net operating loss carry-forwards [Line Items]
Net operating loss carry-forwards	17,500,000								17,500,000
Foreign [Member]
Net operating loss carry-forwards [Line Items]
Net operating loss carry-forwards	$ 20,700,000								$ 20,700,000