STOCK BASED COMPENSATION Schedule of shared based arrangement (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Nov. 30, 2014	Nov. 30, 2013	Aug. 31, 2014	Aug. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares Authorized	45,000,000us-gaap_CommonStockSharesAuthorized		45,000,000us-gaap_CommonStockSharesAuthorized
Options granted to directors	$ 27us-gaap_StockOptionPlanExpense	$ 29us-gaap_StockOptionPlanExpense
Restricted stock awards	1,249psmt_RestrictedStockAwardExpense	1,151psmt_RestrictedStockAwardExpense
Restricted stock units	280psmt_RestrictedStockUnitExpense	250psmt_RestrictedStockUnitExpense
Stock-based compensation expense	1,556us-gaap_ShareBasedCompensation	1,430us-gaap_ShareBasedCompensation
Remaining unrecognized compensation cost (in thousands)	18,002	24,014
Weighted average period of time over which this cost will be recognized (years)	6 years	7 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	488,416	622,425	488,416	623,424
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	0	(999)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 0.00	$ 0.00
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	$ 0.00	$ 0.00
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period, Weighted Average Grant Date Fair Value	$ 0.00	$ 53.62
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Shares Purchased for Award	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Shares Purchased for Award, Amount	$ 0	$ 0
Stock Issued During Period, Shares, Treasury Stock Reissued	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	23,000		23,000
2013 Equity Incentive Award Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares Authorized				1,531,818
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	838,766			600,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	821,124		821,124

The noncash expense that represents the cost of restricted stock award distributed to employees as compensation.

No definition available.

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- Definition

The noncash expense that represents the cost of restricted stock units distributed to employees as compensation.

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Shares Purchased for Award, Amount

+ References

No definition available.

+ Details

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(3)

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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-Publisher FASB

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-Topic 718

-SubTopic 10

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-Paragraph 2

-Subparagraph (c)(2)(iii)(3)

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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-Publisher FASB

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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-Name Accounting Standards Codification

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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-Publisher FASB

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-Topic 718

-SubTopic 10

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-Paragraph 2

-Subparagraph (a)(3)

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

The number of shares purchased on the open market during the period for issuance to employees under the plan.

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- Definition

Number of treasury shares (units) reissued during the period, excluding reissuance of shares (units) held in treasury used to satisfy equity-based compensation obligations exercised by the holders of such rights. Upon reissuance of shares (units) from treasury, either the common or preferred stock (unit) reissued is outstanding.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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- Definition

The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

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-Paragraph 28

-Subparagraph (b)

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