Income Taxes (Details) - USD ($)	12 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2018
Income Taxes
Domestic	$ 52,730,000	$ 50,644,000	$ 32,651,000
Foreign	(60,000)	(166,000)	(34,000)
Income from continuing operations before income taxes	52,670,000	50,478,000	32,617,000
Equity method investment loss, net of tax	(5,487,000)	(3,944,000)	(1,283,000)
Income (loss) before income taxes	47,183,000	$ 46,534,000	$ 31,334,000
Deferred tax liabilities for income taxes on undistributed earnings	$ 0

Amount of deferred tax liability attributable to taxable temporary differences from undistributed earnings of subsidiary and other recognized entity not within country of domicile. Includes, but is not limited to, other basis differences.

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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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