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INCOME TAXES - Income Tax Expense Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended		12 Months Ended
	Oct. 31, 2020	Apr. 30, 2020	Oct. 31, 2019	Oct. 31, 2020	Oct. 31, 2019	Jan. 31, 2020
Federal corporate income tax rate (as percent)				21.00%		21.00%
Computed expected income tax (expense) benefit				$ (2,702)	$ 8,070
Net operating loss carryback		$ 4,400		4,390
Foreign tax rate differential				(77)	(766)
Stock options				66	(170)
State income taxes, net of federal tax effect				(40)	185
Net operating losses deemed unrealizable					(6,280)
Bad debt loss					5,026
Adjustments and other permanent differences				(246)	(1,129)
Income tax benefit	$ (1,666)		$ (1,996)	1,391	4,936
Tax benefit from subsidiaries				$ 100
United Kingdom
Deferred tax valuation allowance			$ 6,300		$ 6,300