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Description of Business and Summary of Significant Accounting Policies (Details Textual) $ in Thousands | 12 Months Ended |
--- | --- | ---
Jul. 31, 2019 USD ($) Segment Customer | Jul. 31, 2018 USD ($) Segment Customer | Jul. 31, 2017 USD ($) Customer | Aug. 01, 2019 USD ($)
Description of Business and Summary of Significant Accounting Policies (Textual) |  |  |  |
Number of reportable segments | Segment | 2 | 2 |  |
Investments accounted for using the equity method | $ 5,400 | $ 4,700 |  |
Investments accounted for using the cost method |  | 1,900 |  |
Restricted cash and cash equivalents | 13,400 | 10,700 |  |
Advertising expense | 17,700 | 16,300 | $ 17,400 |
Amortization expense related to capitalized software | 16,300 | 16,100 | $ 14,200 |
Unamortized capitalized internal use software costs | $ 21,900 | $ 24,900 |  |
Tax position ultimate settlement, percentage | 50.00% |  |  |
Concentration risk, description | No single customer accounted for more than 10% of consolidated revenues. |  |  |
Operating lease liability |  |  |  | $ 12,400
Customer Lists [Member] | Sales Revenue, Net [Member] |  |  |  |
Description of Business and Summary of Significant Accounting Policies (Textual) |  |  |  |
Number of customers | Customer | 5 | 5 | 5 |
Concentration risk, percentage | 13.60% | 12.50% | 12.40% |
Customer Lists [Member] | Accounts Receivable [Member] |  |  |  |
Description of Business and Summary of Significant Accounting Policies (Textual) |  |  |  |
Number of customers | Customer | 5 | 5 |  |
Concentration risk, percentage | 20.60% | 18.70% |  |
Equipment [Member] |  |  |  |
Description of Business and Summary of Significant Accounting Policies (Textual) |  |  |  |
Estimated useful lives of long-lived assets | 7 years |  |  |
Computer Software [Member] |  |  |  |
Description of Business and Summary of Significant Accounting Policies (Textual) |  |  |  |
Estimated useful lives of long-lived assets | 3 years |  |  |
Furniture and Fixtures [Member] |  |  |  |
Description of Business and Summary of Significant Accounting Policies (Textual) |  |  |  |
Estimated useful lives of long-lived assets | 7 years |  |  |
Software and Software Development Costs [Member] |  |  |  |
Description of Business and Summary of Significant Accounting Policies (Textual) |  |  |  |
Estimated useful lives of internal-use software | Capitalizes the cost of internal-use software that has a useful life in excess of one year. |  |  |
Minimum [Member] | Equipment [Member] |  |  |  |
Description of Business and Summary of Significant Accounting Policies (Textual) |  |  |  |
Estimated useful lives of long-lived assets | 5 years |  |  |
Minimum [Member] | Computer Software [Member] |  |  |  |
Description of Business and Summary of Significant Accounting Policies (Textual) |  |  |  |
Estimated useful lives of long-lived assets | 2 years |  |  |
Minimum [Member] | Furniture and Fixtures [Member] |  |  |  |
Description of Business and Summary of Significant Accounting Policies (Textual) |  |  |  |
Estimated useful lives of long-lived assets | 5 years |  |  |
Maximum [Member] | Equipment [Member] |  |  |  |
Description of Business and Summary of Significant Accounting Policies (Textual) |  |  |  |
Estimated useful lives of long-lived assets | 20 years |  |  |
Maximum [Member] | Computer Software [Member] |  |  |  |
Description of Business and Summary of Significant Accounting Policies (Textual) |  |  |  |
Estimated useful lives of long-lived assets | 5 years |  |  |
Maximum [Member] | Furniture and Fixtures [Member] |  |  |  |
Description of Business and Summary of Significant Accounting Policies (Textual) |  |  |  |
Estimated useful lives of long-lived assets | 10 years |  |  |

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