CASH, CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS (Details) - Held-to-maturity Securities - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Oct. 31, 2020	Jan. 31, 2020
Cash and Cash Equivalents
Maturity period	292 days	165 days
Accrued interest on held-to-maturity securities		$ 0.5
Weighted average annual interest rates of CDs (as a percent)	0.20%	1.80%