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CASH, CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS (Details) - Held-to-maturity Securities - USD ($) $ in Millions | 12 Months Ended
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Jan. 31, 2019 | Jan. 31, 2018
Cash and Cash Equivalents |  |
Maturity period | 250 days | 293 days
Accrued interest on held-to-maturity securities | $ 1.2 | $ 1.9
Weighted average annual interest rates of CDs (as a percent) | 2.60% | 1.50%

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- Definition Accumulated Accrued Interest On Held To Maturity Securities + References No definition available. + Details
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Balance Type: | debit
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- Definition Represents the maturity period of investments. + References No definition available. + Details
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Balance Type: | na
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- Definition Weighted average interest rate for certificates of deposit liabilities in banking offices. + References No definition available. + Details
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Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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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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