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COMMITMENTS - Employee Benefit Plans (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Jan. 31, 2021 | Jan. 31, 2020 | Jan. 31, 2019
Employee Benefit Plans |  |  |
Company's expense for defined contribution savings plans | $ 1.9 | $ 1.7 | $ 2.4
Minimum |  |  |
Employee Benefit Plans |  |  |
Deferred period | 5 years |  |
Maximum |  |  |
Employee Benefit Plans |  |  |
Deferred period | 7 years |  |

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- Definition Period of define contribution plan deferred period, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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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. + References No definition available. + Details
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- Details
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