Employee Benefits (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Aug. 31, 2013	Aug. 31, 2012	Aug. 31, 2011	Oct. 01, 2012
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]
Defined Contribution Plan, Period Contributions	$ 2	$ 3	$ 3
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	17	17
Defined Benefit Plan, Benefit Obligation	15	18
Defined Benefit Plan, Funded Status of Plan	3	(1)
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	4.73%	3.67%
Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	17	16
Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		1
Multiemployer Plans
Defined Benefit Plan Disclosure [Line Items]
Number of Multiemployer Plans	13
Multiemployer Plan, Period Contributions	4	4	3
Steelworkers Western Independent Shops Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date	Mar. 31, 2016
Multiemployer Plans, Annual Contribution Rate Increase	0.06
IRC 412(e) Funded Ratio				72.30%
Multiemployer Plan, Period Contributions	3	2	2
Supplemental Employee Retirement Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	2	2
Defined Benefit Plan, Benefit Obligation	3	4
Defined Benefit Plan, Funded Status of Plan	(3)	(4)
Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months	1
Minimum | Steelworkers Western Independent Shops Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Rehabilitation Plan Contributions As A Percent Of Total Contributions	5.00%	5.00%	5.00%
Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months	$ 3