Fair Value Measurements - Additional Information (Detail) - USD ($) |
3 Months Ended | 9 Months Ended | ||
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Jul. 31, 2018 |
Oct. 31, 2018 |
Jan. 31, 2018 |
Oct. 31, 2017 |
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| Fair Value Measurements Disclosure [Line Items] | ||||
| Fair value measurements of our financial assets and liabilities | $ 13,117,000 | $ 13,008,000 | ||
| Impairment charges on goodwill | $ 0 | |||
| Impairment charges on other long-lived assets | $ 0 | |||
| Maximum maturity of marketable securities | 90 days or less | |||
| Cash equivalents and marketable securities | $ 32,400,000 | 52,100,000 | ||
| Restricted cash | 543,000 | 9,000 | $ 8,000 | |
| Fair Value, Inputs, Level 3 [Member] | ||||
| Fair Value Measurements Disclosure [Line Items] | ||||
| Fair value measurements of our financial assets and liabilities | $ 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 Fair value of asset after deduction of liability. No definition available.
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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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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