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Net Income per Common and Common Equivalent Share Net Income per Common and Common Equivalent Share (Tables) | 12 Months Ended
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Sep. 02, 2018
Earnings Per Share [Abstract] |
Schedule of Earnings Per Share, Basic and Diluted | The following table shows the amounts used in computing net income per share and the weighted average number of shares of potentially dilutive common shares outstanding (shares in 000’s):
| 2018 |  | 2017 |  | 2016
Net income attributable to Costco | $ | 3,134 |  |  | $ | 2,679 |  |  | $ | 2,350 |
Weighted average number of common shares used in basic net income per common share | 438,515 |  |  | 438,437 |  |  | 438,585 |
RSUs and other | 3,319 |  |  | 2,500 |  |  | 2,678 |
Weighted average number of common shares and dilutive potential of common stock used in diluted net income per share | 441,834 |  |  | 440,937 |  |  | 441,263 |

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- Definition Tabular disclosure of an entity's basic and diluted earnings per share calculations, including a reconciliation of numerators and denominators of the basic and diluted per-share computations for income from continuing operations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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