Fair Value Measurements - Summary of Marketable Securities by Security Type (Detail) - USD ($) $ in Thousands |
Apr. 30, 2020 |
Jan. 31, 2020 |
|---|---|---|
| Schedule Of Available For Sale Securities [Line Items] | ||
| Amortized Cost | $ 3,367 | $ 4,564 |
| Gross Unrealized Gains | 63 | 53 |
| Fair Value | 3,430 | 4,617 |
| U.S. Treasury Notes and Bonds [Member] | ||
| Schedule Of Available For Sale Securities [Line Items] | ||
| Amortized Cost | 3,114 | 3,310 |
| Gross Unrealized Gains | 59 | 50 |
| Fair Value | 3,173 | 3,360 |
| Corporate Bonds [Member] | ||
| Schedule Of Available For Sale Securities [Line Items] | ||
| Amortized Cost | 253 | 1,254 |
| Gross Unrealized Gains | 4 | 3 |
| Fair Value | $ 257 | $ 1,257 |
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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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