Goodwill and intangible assets (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Jul. 31, 2017 |
Jul. 31, 2016 |
Jul. 31, 2015 |
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| Goodwill and intangible assets (Details) [Line Items] | |||
| Goodwill | $ 7,452 | $ 7,452 | |
| Finite-Lived Intangible Asset, Useful Life | 10 years | ||
| Amortization of Intangible Assets | $ 1,520 | $ 1,677 | $ 1,770 |
| Intangible Assets, Amortization Period [Member] | |||
| Goodwill and intangible assets (Details) [Line Items] | |||
| Finite-Lived Intangible Asset, Useful Life | 2 years | ||
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- References No definition available.
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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. No definition available.
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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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