Condensed Consolidated Balance Sheets (Parenthetical) $ in Thousands	Oct. 31, 2020 USD ($) shares	Oct. 31, 2020 € / shares	Apr. 30, 2020 USD ($) shares	Apr. 30, 2020 € / shares
Statement of Financial Position [Abstract]
Allowance for credit losses \| $	$ 1,505		$ 1,247
Ordinary shares, par value (€ / share) \| € / shares		€ 0.01		€ 0.01
Ordinary shares, shares authorized (in shares)	165,000,000		165,000,000
Ordinary shares, shares issued (in shares)	87,204,991		82,856,978
Ordinary shares, shares outstanding (in shares)	87,204,991		82,856,978
Convertible Preference Shares
Convertible preference shares, par value (€ / share) \| € / shares		€ 0.01		€ 0.01
Convertible preference shares authorized (in shares)	165,000,000		165,000,000
Convertible preference shares issued (in shares)	0		0
Convertible preference shares outstanding (in shares)	0		0

Amount of allowance for credit loss on accounts receivable, classified as current.

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