Income Taxes - Components of income before taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2018
Income before taxes	$ 46,325	$ 70,041	$ 83,854
Domestic
Income before taxes	106,850	62,878	$ 83,854
Foreign
Income before taxes	$ (60,525)	$ 7,163

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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