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Summary of Significant Accounting Policies - Additional Information (Detail) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Feb. 17, 2019 USD ($) warehouse states | Feb. 18, 2018 USD ($) | Feb. 17, 2019 USD ($) warehouse states | Feb. 18, 2018 USD ($) | Sep. 02, 2018 USD ($)
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Number of warehouses operated | warehouse | 769 |  | 769 |  |
Number of states in country | states | 44 |  | 44 |  |
Total Revenue | $ 35,396 | $ 32,995 | $ 70,465 | $ 64,804 |
Reduction In Sales | 364 | 329 | 714 | 646 |
Revenue Recognition, Sales Returns, Reserve for Sales Returns | 731 |  | 731 |  | $ 649
Merchandise costs | 30,720 | 28,733 | 61,343 | 56,350 |
Gross Margin (1) | 3,908 |  | 7,596 |  |
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets | 16 |  | 16 |  |
Membership fees |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Total Revenue | 768 | 716 | 1,526 | 1,408 |
Deferred Revenue, Current |  |  | 1,144 |  |
Net Sales |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Total Revenue | 34,628 | $ 32,279 | 68,939 | $ 63,396 |
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Merchandise costs | 183 |  | 514 |  |
Gross Margin (1) | (4) |  | 5 |  |
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Net Sales |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Total Revenue | 179 |  | 519 |  |
Calculated under Revenue Guidance in Effect before Topic 606 [Member] |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Merchandise costs | 30,537 |  | 60,829 |  |
Gross Margin (1) | 3,912 |  | 7,591 |  |
Calculated under Revenue Guidance in Effect before Topic 606 [Member] | Net Sales |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Total Revenue | $ 34,449 |  | $ 68,420 |  |
UNITED STATES |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Number of warehouses operated | warehouse | 534 |  | 534 |  |
CANADA |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Number of warehouses operated | warehouse | 100 |  | 100 |  |
MEXICO |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Number of warehouses operated | warehouse | 39 |  | 39 |  |
UNITED KINGDOM |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Number of warehouses operated | warehouse | 28 |  | 28 |  |
JAPAN |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Number of warehouses operated | warehouse | 26 |  | 26 |  |
KOREA |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Number of warehouses operated | warehouse | 15 |  | 15 |  |
TAIWAN |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Number of warehouses operated | warehouse | 13 |  | 13 |  |
AUSTRALIA |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Number of warehouses operated | warehouse | 10 |  | 10 |  |
SPAIN |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Number of warehouses operated | warehouse | 2 |  | 2 |  |
ICELAND |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Number of warehouses operated | warehouse | 1 |  | 1 |  |
FRANCE |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Number of warehouses operated | warehouse | 1 |  | 1 |  |

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