CONSOLIDATED STATEMENTS OF INCOME (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Nov. 30, 2013	Nov. 30, 2012
Revenues:
Net warehouse club sales	$ 589,694	$ 523,599
Export sales	5,721	3,073
Membership income	9,268	7,673
Other income	918	941
Total revenues	605,601	535,286
Cost of goods sold:
Net warehouse club	504,287	444,944
Export	5,441	2,835
Selling, general and administrative:
Warehouse club operations	51,772	45,842
General and administrative	11,184	11,158
Pre-opening expenses	474	737
Loss/(gain) on disposal of assets	84	57
Total operating expenses	573,242	505,573
Operating income	32,359	29,713
Other income (expense):
Interest income	181	294
Interest expense	(1,038)	(1,218)
Other income (expense), net	311	(1)
Total other expense	(546)	(925)
Income from continuing operations before provision for income taxes and loss of unconsolidated affiliates	31,813	28,788
Provision for income taxes	(10,385)	(8,779)
Income (loss) of unconsolidated affiliates	4	(4)
Net income	$ 21,432	$ 20,005
Net income per share available for distribution:
Basic net income per share from continuing operations (in dollars per share)	$ 0.71	$ 0.66
Basic net income per share (in dollars per share)	$ 0.71	$ 0.66
Diluted net income per share from continuing operations (in dollars per share)	$ 0.71	$ 0.66
Diluted net income per share (in dollars per share)	$ 0.71	$ 0.66
Shares used in per share computations:
Basic (in shares)	29,690	29,592
Diluted (in shares)	29,702	29,604
Dividends per share (in dollars per share)	$ 0.00	$ 0.60
Statement [Line Items]
Document Fiscal Year Focus	2014