LEASES (Summary of Rental Income) (Details) - USD ($) $ in Thousands	12 Months Ended
Aug. 31, 2018	Aug. 31, 2017	Aug. 31, 2016
LEASES [Abstract]
Minimum rental receipts	$ 2,750	$ 2,654	$ 2,735
Deferred rent accruals	(26)	(17)	56
Total straight line rent income	2,724	2,637	2,791
Contingent rental receipts	130	121	112
Common maintenance area income	155	141	151
Rental income	$ 3,009	$ 2,899	$ 3,054

Represents the cash payments from the tenant related to the common area maintenance.

No definition available.

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Balance Type:	credit
Period Type:	duration

- Definition

Represents the difference between the straight-line income and the cash payments from the tenant over the life of the lease.

+ References

No definition available.

+ Details

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Namespace Prefix:	psmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the straight-line income of the lease

+ References

No definition available.

+ Details

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Namespace Prefix:	psmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_LeasesAbstract
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of contingent rental revenue recognized for the period under lease, based on the occurrences of an event or condition.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84164653&loc=d3e41551-112718

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77902458&loc=d3e39896-112707

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The total amount of lease revenue recognized for the period for which the lessee was obligated under leasing arrangements regardless of any other events or conditions. This amount excludes contingent revenue and sublease revenue.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration