Income Taxes (Details) - USD ($)	12 Months Ended
Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2016
Income Taxes
Domestic	$ 33,854,000	$ 20,954,000	$ 18,433,000
Foreign	(34,000)	(86,000)	81,000
Income from continuing operations before income taxes	33,820,000	20,868,000	18,514,000
Equity method investment activity, net of tax	(1,283,000)	(119,000)	(138,000)
Income (loss) before income taxes	32,537,000	$ 20,749,000	$ 18,376,000
Deferred tax liabilities for income taxes on undistributed earnings	$ 0

Amount of deferred tax liability attributable to taxable temporary differences from undistributed earnings of subsidiaries and other recognized entities not within the country of domicile of the entity.

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The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

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