INVESTMENTS (Details) - USD ($) $ in Millions	Apr. 30, 2019	Jan. 31, 2019
INVESTMENTS (Details) [Line Items]
Debt Securities, Held-to-maturity, Maturity, Rolling within One Year, Weighted Average Yield		2.29%
Big River [Member]
INVESTMENTS (Details) [Line Items]
Retained Earnings, Undistributed Earnings from Equity Method Investees	$ 12.2	$ 12.0

Weighted average yield of investment in debt security measured at amortized cost (held-to-maturity), maturing in next rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section II
-Paragraph B

Name:	us-gaap_DebtSecuritiesHeldToMaturityMaturityRollingWithinOneYearWeightedAverageYield
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant