INCOME TAXES - Income Tax Expense Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Jan. 31, 2020
Federal corporate income tax rate (as percent)	21.00%	21.00%	21.00%
Computed expected income tax benefit	$ 1,102	$ 6,391
Net operating loss carryback	4,175
Net operating losses deemed unrealizable	(695)	(5,316)
Foreign tax rate differential	(111)	(754)
Adjustments and other permanent differences	(17)	200
Income tax benefit	4,454	521
United Kingdom
Deferred tax valuation allowance		$ 5,300
Increase in deferred tax valuation allowance	$ 700

The amount of benefits that will be realized from the carryback of net operating loss incurred.

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Represents the amount of net operating losses deemed unrealizable.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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