Fair Value Measurements - Additional Information (Detail) |
Apr. 30, 2019
USD ($)
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| Fair Value Measurements Disclosure [Line Items] | |
| Marketable securities fair value, mature between one and three years | $ 4,600,000 |
| Fair Value, Inputs, Level 3 [Member] | |
| Fair Value Measurements Disclosure [Line Items] | |
| Fair value measurements of our financial assets | $ 0 |
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- Definition Fair value of available for sale investments that mature between one and three years. No definition available.
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- Definition Fair Value Measurements Disclosure [Line Items] No definition available.
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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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