Business Combinations (Details) $ in Thousands	12 Months Ended
	Aug. 31, 2013 USD ($)	Aug. 31, 2015 USD ($)	Aug. 31, 2014 USD ($)	Nov. 30, 2013 store	Jun. 30, 2013 store	Dec. 31, 2012 store
Business Acquisition [Line Items]
Goodwill		$ 175,676	$ 325,903
Pick A Part, Inc.
Business Acquisition [Line Items]
Number of Stores | store				1
Ralphs Auto Supply (B.C.) Ltd
Business Acquisition [Line Items]
Number of Stores | store						4
U-Pick-It
Business Acquisition [Line Items]
Number of Stores | store						2
Freetown - Millis Used Auto Parts
Business Acquisition [Line Items]
Number of Stores | store						2
Bill’s Auto Parts, Inc. and Perkins Horshoe Works, Inc.
Business Acquisition [Line Items]
Number of Stores | store					1
Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Consideration Transferred	$ 26,000
Goodwill	20,000
Goodwill, Expected Tax Deductible Amount	18,000
Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual	11,000
Pro Forma Information, Operating Income (Loss) of Acquiree since Acquisition Date, Actual	$ (4,000)