Fair Value Measurements - Additional Information (Detail) - USD ($) |
3 Months Ended | 6 Months Ended | |
|---|---|---|---|
Jul. 31, 2017 |
Jul. 31, 2017 |
Jan. 31, 2017 |
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| Fair Value Measurements Disclosure [Line Items] | |||
| Fair value measurements of our financial assets and liabilities | $ 12,988,000 | $ 12,988,000 | $ 12,970,000 |
| 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 | 35,600,000 | $ 35,600,000 | 38,700,000 |
| 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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- Details
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