Income Taxes - Summary of Geographical Breakdown of Income (Loss) Before Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2018
Income Tax Disclosure [Abstract]
Dutch	$ (173,338)	$ (121,803)	$ (58,810)
Foreign	4,196	23,888	9,459
Loss before income taxes	$ (169,142)	$ (97,915)	$ (49,351)

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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+ Details