Related Party Transactions (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	1 Months Ended	3 Months Ended			3 Months Ended					3 Months Ended		3 Months Ended
	Nov. 30, 2011 Immediate Family Member of Management or Principal Owner [Member]	Nov. 30, 2010 Corporate Joint Venture [Member]	Nov. 30, 2010 Corporate Joint Venture [Member]	Nov. 30, 2011 Corporate Joint Venture [Member]	Aug. 31, 2011 Corporate Joint Venture [Member]	Nov. 30, 2011 Corporate Joint Venture [Member]	Nov. 30, 2010 Corporate Joint Venture [Member]	Nov. 30, 2011 Maximum [Member] Immediate Family Member of Management or Principal Owner [Member]	Aug. 31, 2011 Maximum [Member] Immediate Family Member of Management or Principal Owner [Member]	Nov. 30, 2010 Maximum [Member] Immediate Family Member of Management or Principal Owner [Member]	Nov. 30, 2011 Maximum [Member] Corporate Joint Venture [Member]	Nov. 30, 2011 Partnership Interest [Member] store	Nov. 30, 2011 Partnership Interest [Member] Auto Parts Business Segment President [Member]	Nov. 30, 2010 Partnership Interest [Member] Auto Parts Business Segment President [Member]	Nov. 30, 2011 Partnership Interest [Member] Property One [Member] Auto Parts Business Segment President [Member]	Nov. 30, 2011 Partnership Interest [Member] Property One [Member] Maximum [Member] Auto Parts Business Segment President [Member]	Nov. 30, 2010 Partnership Interest [Member] Property One [Member] Maximum [Member] Auto Parts Business Segment President [Member]	Nov. 30, 2011 Partnership Interest [Member] Property Two [Member] Auto Parts Business Segment President [Member]	Nov. 30, 2011 Partnership Interest [Member] Property Two [Member] Maximum [Member] Auto Parts Business Segment President [Member]	Nov. 30, 2010 Partnership Interest [Member] Property Two [Member] Maximum [Member] Auto Parts Business Segment President [Member]	Nov. 30, 2011 Partnership Interest [Member] Property Three [Member] Auto Parts Business Segment President [Member]	Nov. 30, 2011 Partnership Interest [Member] Property Three [Member] Maximum [Member] Auto Parts Business Segment President [Member]	Nov. 30, 2011 Amix Salvage And Sales Ltd [Member] Minority Shareholder Of Subsidiary [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction						$ 10	$ 10
Payments for Advance to Affiliate			(1)								(1)
Due to Affiliate				3	2
Investments in and Advances to Affiliates, at Fair Value, Gross Additions		2
Related Party Transaction, Expenses from Transactions with Related Party																							3
Related Party Noncontrolling Ownership Percentage By Noncontrolling Owners													25.00%
Related Party Noncontrolling Ownership Percentage By Parent													75.00%
Related Party Number Of Stores												4
Related Party Transaction Related Party Share Of Profit													1	1
Related Party Transaction Rent Expense																1	1		1	1		1
Related Party Transaction Lease Term															5 years			5 years
Related Party Transaction, Lease Term, Extension Period																					6 months
Related Party Transaction Percentage Of Shared Legal And Consulting Costs	50.00%
Accounts Payable, Related Parties								(1)
Accounts Receivable, Related Parties									$ 1	$ 1