Fair Value Measurements - Schedule of Contractual Maturities Available-for-Sale Debt Securities (Detail) $ in Thousands |
Jan. 31, 2018
USD ($)
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| Fair Value Disclosures [Abstract] | |
| Maturity of one year or less | $ 3,991 |
| Maturity between one and five years | 4,449 |
| Total | $ 8,440 |
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- Definition Fair value of available-for-sale debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value of available-for-sale debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of debt securities categorized neither as held-to-maturity nor trading. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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