Fair Value Measurements - Additional Information (Detail) - USD ($) |
3 Months Ended | 9 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|---|
Oct. 31, 2017 |
Oct. 31, 2016 |
Oct. 31, 2017 |
Oct. 31, 2016 |
Jan. 31, 2017 |
Aug. 01, 2017 |
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| Fair Value Measurements Disclosure [Line Items] | ||||||
| Fair value measurements of our financial assets and liabilities | $ 13,025,000 | $ 13,025,000 | $ 12,970,000 | |||
| Impairment charge | 0 | 0 | ||||
| Loss on impairment of long-lived assets held for sale | $ 100,000 | $ 100,000 | 300,000 | |||
| Impairment charges related to goodwill, intangible assets, long-lived assets or cost-method investments | 0 | $ 0 | ||||
| Maximum maturity of marketable securities | Three months or less | |||||
| Cash equivalents and marketable securities | 36,600,000 | $ 36,600,000 | 38,700,000 | |||
| DCC Labs [Member] | ||||||
| Fair Value Measurements Disclosure [Line Items] | ||||||
| Fair value of reporting unit | $ 64,200,000 | |||||
| Impairment charge | 0 | |||||
| Fair Value, Inputs, Level 3 [Member] | ||||||
| Fair Value Measurements Disclosure [Line Items] | ||||||
| Fair value measurements of our financial assets and liabilities | $ 0 | $ 0 | $ 0 | |||
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- Definition Aggregate cash, cash equivalents, short term investments and restricted cash. No definition available.
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- Definition Cash Equivalents Maximum Maturity Period No definition available.
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- Definition Fair Value Measurements Disclosure [Line Items] No definition available.
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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value of asset after deduction of liability. No definition available.
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- Definition Fair value portion of asset representing the 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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- Definition Amount of loss from the write-down of an asset representing the 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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- Definition The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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