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Earnings (Loss) Per Share (Details 1) - shares shares in Thousands | 3 Months Ended | 6 Months Ended
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Jan. 31, 2019 | Jan. 31, 2018 | Jan. 31, 2019 | Jan. 31, 2018
Shares were excluded from the diluted earnings per share computations |  |  |  |
Shares excluded from the calculation of diluted earnings per share | 1,243 | 1,160 | 1,263 | 1,464
Stock options [Member] |  |  |  |
Shares were excluded from the diluted earnings per share computations |  |  |  |
Shares excluded from the calculation of diluted earnings per share | 1,243 | 1,160 | 1,243 | 1,273
Non-vested restricted Class B common stock [Member] |  |  |  |
Shares were excluded from the diluted earnings per share computations |  |  |  |
Shares excluded from the calculation of diluted earnings per share |  |  | 20 | 191

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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. + 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 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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