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Related Party Transactions (Details) - Straight Path [Member] - USD ($) $ in Thousands | 12 Months Ended
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Jul. 31, 2018 | Jul. 31, 2017
Estimated liability to straight path included in other current liabilities |  |
Balance at beginning of year | $ 81 | $ 133
Additional liability |  | 104
Adjustments | (46) | (51)
Payments | (35) | (105)
Balance at end of year |  | $ 81

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- Definition Change in balance of estimated liability adjustments. + References No definition available. + Details
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- Definition Change in balance of estimated liability included in other current liabilities. + References No definition available. + Details
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- Definition Change in balance of estimated liability payments. + References No definition available. + Details
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Balance Type: | debit
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- References No definition available. + Details
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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |