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INCOME TAXES - The Tax Cuts and Jobs Act (the "Tax Act") (Details) - USD ($) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Oct. 31, 2018 | Jan. 31, 2018
INCOME TAXES |  |
Federal corporate income tax rate (as percent) | 21.00% | 35.00%
Income tax benefit |  | $ 0.8

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