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INCOME TAXES - Income Tax Expense Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019	Jan. 31, 2020
Federal corporate income tax rate (as percent)			21.00%		21.00%
Computed expected income tax (expense) benefit			$ (367)	$ 7,532
Net operating loss carryback			4,286
State income taxes, net of federal tax effect			(44)	490
Bad debt loss				5,016
Net operating losses deemed unrealizable			(582)	(6,112)
Foreign tax rate differential			(25)	(838)
Stock options			38	204
Adjustments and other permanent differences			(249)	640
Income tax benefit	$ (1,397)	$ 6,411	3,057	6,932
United Kingdom
Deferred tax valuation allowance		$ 6,100		$ 6,100
Increase in deferred tax valuation allowance			$ 600