Income Taxes	9 Months Ended
May 31, 2012
Notes to Condensed Consolidated Financial Statements [Abstract]
Income Taxes	Income Taxes We determine our interim income tax provision by estimating our effective income tax rate expected to be applicable for the full fiscal year. Our effective income tax rate is dependent upon several factors, such as tax rates in state and foreign jurisdictions and the relative amount of income we earn in such jurisdictions. In determining our full year estimate, we do not include the estimated impact of unusual and/or infrequent items, which may cause significant variations in the customary relationship between income tax expense and income before income taxes. We exercise significant judgment in determining our income tax provision due to transactions, credits and calculations where the ultimate tax determination is uncertain. The decrease in the current portion of our net deferred tax assets as of May 31, 2012 compared to August 31, 2011 was principally attributable to the reversal of a deferred tax asset related to our $145.0 million settlement payment associated with the Securities Class Action (Policeman’s Annuity and Benefit Fund of Chicago) matter, which became deductible in the third quarter of fiscal year 2012. Refer to Note 15, Commitments and Contingencies. We are subject to numerous ongoing audits by federal, state, local and foreign tax authorities. Although we believe our tax accruals to be reasonable, the final determination of tax audits in the U.S. or abroad and any related litigation could be materially different from our historical income tax provisions and accruals.

Income Taxes

9 Months Ended

May 31, 2012

Notes to Condensed Consolidated Financial Statements [Abstract]

We determine our interim income tax provision by estimating our effective income tax rate expected to be applicable for the full fiscal year. Our effective income tax rate is dependent upon several factors, such as tax rates in state and foreign jurisdictions and the relative amount of income we earn in such jurisdictions. In determining our full year estimate, we do not include the estimated impact of unusual and/or infrequent items, which may cause significant variations in the customary relationship between income tax expense and income before income taxes. We exercise significant judgment in determining our income tax provision due to transactions, credits and calculations where the ultimate tax determination is uncertain.

The decrease in the current portion of our net deferred tax assets as of May 31, 2012 compared to August 31, 2011 was principally attributable to the reversal of a deferred tax asset related to our $145.0 million settlement payment associated with the Securities Class Action (Policeman’s Annuity and Benefit Fund of Chicago) matter, which became deductible in the third quarter of fiscal year 2012. Refer to Note 15, Commitments and Contingencies.

We are subject to numerous ongoing audits by federal, state, local and foreign tax authorities. Although we believe our tax accruals to be reasonable, the final determination of tax audits in the U.S. or abroad and any related litigation could be materially different from our historical income tax provisions and accruals.