XML 61 R34.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
CASH, CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS (Details) - Held-to-maturity Securities - USD ($)
$ in Millions
 9 Months Ended 12 Months Ended
Oct. 31, 2019
Jan. 31, 2019
Cash and Cash Equivalents    
Maturity period 147 days 250 days
Accrued interest on held-to-maturity securities $ 0.1 $ 1.2
Weighted average annual interest rates of CDs (as a percent) 1.90% 2.60%