LONG-TERM DEBT - INTEREST EXPENSE (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
1.50% Convertible Senior Notes
Debt Instrument
Interest Expense at Coupon or Contractual Rate	$ 1,500	$ 1,500
Amortization of Debt Discount	3,226	3,061
Amortization of Deferred Debt Issuance Costs	304	289
Total Interest Expense	5,030	4,850
Credit Agreements
Debt Instrument
Interest Expense at Coupon or Contractual Rate	4,513	4,645
Amortization of Debt Discount	18	16
Amortization of Deferred Debt Issuance Costs	391	374
Derivative Instruments, gains (losses) Reclassified from Accumulated OCI into Income, Effective Portion, Net	591	0
Total Interest Expense	$ 5,513	$ 5,035