| **Stock Repurchase Plan**                        | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
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| **Payments for Repurchase of Equity [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| Stock Repurchase Plan                            | Stock Repurchase PlanOn March 9, 2006, the Company’s Board of Directors approved the repurchase of up to 3,000,000 shares of common stock and on July 16, 2008 approved an increase of the Company’s common stock repurchase authorization by an additional 3,000,000 shares. The Company did not repurchase any shares of common stock during the years ended July 31, 2014 and 2013. Since inception of this stock repurchase program through July 31, 2014, the Company has repurchased 4,949,111 shares at a cost of approximately $193.2 million. As of July 31, 2014, 1,050,889 shares remained available to repurchase under the existing repurchase authorization. Shares of common stock purchased pursuant to the repurchase program will be held as treasury shares and may be used for issuance under the Company’s employee share award plan. |

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| - Definition
Tabular disclosure of treasury stock, including, but not limited to, average cost per share, description of share repurchase program, shares repurchased, shares held for each class of treasury stock.
+ References
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