Fair Value Measurements - Additional Information (Detail) - USD ($) |
3 Months Ended | ||
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Apr. 30, 2018 |
Jan. 31, 2018 |
Apr. 30, 2017 |
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| Fair Value Measurements Disclosure [Line Items] | |||
| Fair value measurements of our financial assets and liabilities | $ 13,024,000 | $ 13,008,000 | |
| Maximum maturity of marketable securities | Three months or less | ||
| Restricted cash | $ 0 | 9,000 | $ 7,000 |
| 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 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 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://www.xbrl.org/2003/role/presentationRef
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- Details
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