Discontinued Operations - EES Business (Details) $ in Thousands	12 Months Ended
Apr. 30, 2020 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on sale of business, net of tax benefit of $76 for the year ended April 30, 2020	$ (265)
Net loss from discontinued operations	(265)
Tax expense	76
EES Business \| Disposed of by sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Tax expense	76
EES Business \| Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on sale of business, net of tax benefit of $76 for the year ended April 30, 2020	(265)
Net loss from discontinued operations	$ (265)

Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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+ Details