Income Taxes (Details) - USD ($)	3 Months Ended	12 Months Ended
Jul. 29, 2017	Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2017
Income Taxes
Domestic	$ 32,651,000	$ 50,644,000		$ 22,642,000
Foreign	(34,000)	(166,000)		(86,000)
Income from continuing operations before income taxes	32,617,000	50,478,000	$ 32,617,000	22,556,000
Equity method investment loss, net of tax	(1,283,000)	(3,944,000)	$ (1,283,000)	(119,000)
Income (loss) before income taxes	$ 31,334,000	46,534,000		$ 22,437,000
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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