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Revenue Recognition (Details 2) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
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Apr. 30, 2020 | Apr. 30, 2019 | Apr. 30, 2020 | Apr. 30, 2019
Contract Liabilities [Member] |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |
Revenue recognized in the period from amounts included in the contract liability balance at the beginning of the period | $ 23,600 | $ 25,282 | $ 31,306 | $ 30,363

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- Definition Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045 + Details
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Balance Type: | credit
Period Type: | duration

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |