PROPERTY AND EQUIPMENT, NET Property Plant and Equipment (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Nov. 30, 2014	Nov. 30, 2013	Aug. 31, 2014
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 584,496us-gaap_PropertyPlantAndEquipmentGross		$ 572,374us-gaap_PropertyPlantAndEquipmentGross
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(151,624)		(146,049)
Property, Plant and Equipment, Net	432,872us-gaap_PropertyPlantAndEquipmentNet		426,325us-gaap_PropertyPlantAndEquipmentNet
Depreciation and amortization expense	7,797	6,654
Total interest capitalized	6,332psmt_CapitalizedInterestAtPeriodEnd		6,542psmt_CapitalizedInterestAtPeriodEnd
Interest expense capitalized	616us-gaap_InterestCostsCapitalized	299us-gaap_InterestCostsCapitalized
Accounts Payable, Current	282,435us-gaap_AccountsPayableCurrent		223,559us-gaap_AccountsPayableCurrent
Accrued Liabilities, Current	25,052us-gaap_AccruedLiabilitiesCurrent		21,030us-gaap_AccruedLiabilitiesCurrent
Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	131,133		124,082
Building and Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life, Minimum	10 years
Property, Plant and Equipment, Gross	263,067		244,485
Furniture, Fixtures and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life, Minimum	3 years
Property, Plant and Equipment, Gross	157,698		148,143
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	32,598		55,664
Accounts Payable, Current	2,500		4,100
Accrued Liabilities, Current	$ 1,900		$ 0
End of Useful Life [Member] \| Building and Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life, Minimum	25 years
End of Useful Life [Member] \| Furniture, Fixtures and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life, Minimum	15 years

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Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Amount of interest capitalized during the period.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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