STOCKHOLDERS' EQUITY (Schedule of Components of Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Loss) (Details) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended 12 Months Ended
May 31, 2021
May 31, 2020
May 31, 2021
May 31, 2020
Aug. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]          
Balance, Attributable to PriceSmart     $ 831,719    
Other comprehensive income (loss), Attributable to PriceSmart $ (2,557) $ (15,411) (457) $ (23,590)  
Balance, Attributable to PriceSmart 898,803   898,803   $ 831,719
Balance 875,251 818,867 832,732 798,279 798,279
Balance 899,784 819,603 899,784 819,603 832,732
Accumulated Other Comprehensive Loss [Member]          
Accumulated Other Comprehensive Income (Loss) [Line Items]          
Balance, Attributable to PriceSmart     (176,820) (144,339) (144,339)
Other comprehensive income (loss), Attributable to PriceSmart (2,590) (15,446) (548) (23,680)  
Balance, Attributable to PriceSmart (177,368) (168,019) (177,368) (168,019) (176,820)
Balance (174,778) (152,573) (176,820) (144,339) (144,339)
Balance (177,368) (168,019) (177,368) (168,019) (176,820)
Foreign Currency Translation Adjustments [Member]          
Accumulated Other Comprehensive Income (Loss) [Line Items]          
Other comprehensive income (loss), Attributable to PriceSmart     (2,577) (19,981) (29,413)
Defined Benefit Pension Plans [Member]          
Accumulated Other Comprehensive Income (Loss) [Line Items]          
Other comprehensive income (loss), Attributable to PriceSmart [1]     164 53 (79)
Derivative Instruments [Member]          
Accumulated Other Comprehensive Income (Loss) [Line Items]          
Other comprehensive income (loss), Attributable to PriceSmart [2]     1,865 (3,752) (5,803)
AOCI Attributable to Noncontrolling Interest [Member]          
Accumulated Other Comprehensive Income (Loss) [Line Items]          
Balance     134 20 20
Balance 225 110 225 110 134
Accumulated Foreign Currency Adjustment Attributable to Noncontrolling Interest [Member]          
Accumulated Other Comprehensive Income (Loss) [Line Items]          
Other comprehensive income (loss)     91 90 114
Reclassification From Other Comprehensive Income (Loss) Attributable To Noncontrolling Interest [Member]          
Accumulated Other Comprehensive Income (Loss) [Line Items]          
Amount reclassified from accumulated other comprehensive income (loss), Attributable to PriceSmart         2,814
AOCI Including Portion Attributable to Noncontrolling Interest [Member]          
Accumulated Other Comprehensive Income (Loss) [Line Items]          
Balance     (176,686) (144,319) (144,319)
Balance $ (177,143) $ (167,909) (177,143) (167,909) (176,686)
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest [Member]          
Accumulated Other Comprehensive Income (Loss) [Line Items]          
Other comprehensive income (loss)     (2,486) (19,891) (29,299)
Accumulated Defined Benefit Plans Adjustment Including Portion Attributable to Noncontrolling Interest [Member]          
Accumulated Other Comprehensive Income (Loss) [Line Items]          
Other comprehensive income (loss) [1]     164 53 (79)
Accumulated Derivative Instruments Including Portion Attributable To Noncontrolling Interest [Member]          
Accumulated Other Comprehensive Income (Loss) [Line Items]          
Other comprehensive income (loss) [2]     $ 1,865 $ (3,752) (5,803)
Reclassification From Other Comprehensive Income (Loss) Including Portion Attributable To Noncontrolling Interest [Member]          
Accumulated Other Comprehensive Income (Loss) [Line Items]          
Amounts reclassified from accumulated other comprehensive income (loss)         $ 2,814
[1] Amounts reclassified from accumulated other comprehensive income (loss) related to the minimum pension liability are included in warehouse club and other operations in the Company's consolidated statements of income.
[2] Refer to Note 8 - Derivative Instruments and Hedging Activities.