DEBT Debt - Long Term (Details) (USD $)	Nov. 30, 2014	Aug. 31, 2014
Debt Instrument [Line Items]
Debt Instrument, Collateral, Cash	$ 24,400,000psmt_DebtInstrumentCollateralCash	$ 24,600,000psmt_DebtInstrumentCollateralCash
Debt Instrument, Collateral, Non-Cash	93,400,000psmt_DebtInstrumentCollateralNonCash	84,200,000psmt_DebtInstrumentCollateralNonCash
Long-term Debt, Current Maturities	10,932,000us-gaap_LongTermDebtCurrent	11,848,000us-gaap_LongTermDebtCurrent
Long-term Debt, Excluding Current Maturities	85,378,000us-gaap_LongTermDebtNoncurrent	79,591,000us-gaap_LongTermDebtNoncurrent
Long-term Debt	96,310,000us-gaap_LongTermDebt	91,439,000us-gaap_LongTermDebt
Proceeds from long-term debt [Member] \| HONDURAS
Debt Instrument [Line Items]
Long-term Debt, Current Maturities	1,600,000
Long-term Debt, Excluding Current Maturities	6,750,000
Long-term Debt	8,350,000
Proceeds from long-term debt [Member] \| PANAMA
Debt Instrument [Line Items]
Long-term Debt, Current Maturities	1,000,000
Long-term Debt, Excluding Current Maturities	9,000,000
Long-term Debt	10,000,000
Repayments of long-term debt [Member] \| HONDURAS \| Scotiabank [Member]
Debt Instrument [Line Items]
Long-term Debt, Current Maturities	(3,200,000)
Long-term Debt, Excluding Current Maturities	0
Long-term Debt	(3,200,000)
Repayments of long-term debt [Member] \| HONDURAS \| Banco de America Central [Member]
Debt Instrument [Line Items]
Long-term Debt, Current Maturities	0
Long-term Debt, Excluding Current Maturities	(5,000,000)
Long-term Debt	(5,000,000)
Regularly scheduled loan payments [Member]
Debt Instrument [Line Items]
Long-term Debt, Current Maturities	(316,000)
Long-term Debt, Excluding Current Maturities	(2,109,000)
Long-term Debt	(2,425,000)
Reclassifications of long-term debt [Member]
Debt Instrument [Line Items]
Long-term Debt, Current Maturities	0
Long-term Debt, Excluding Current Maturities	0
Long-term Debt	0
Other Comprehensive Income Location [Domain] \| Reclassifications of long-term debt [Member]
Debt Instrument [Line Items]
Long-term Debt, Current Maturities	0
Long-term Debt, Excluding Current Maturities	(2,854,000)
Long-term Debt	(2,854,000)
Group of Subsidiaries [Member] \| Complies with Financial convenants [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 68,500,000

Debt Instrument, Collateral, Cash

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Debt Instrument, Collateral, Non-Cash

+ References

No definition available.

+ Details

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

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-Section S99

-Paragraph 1

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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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- Definition

Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19,20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19

-Article 5

+ Details

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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