Earnings per share - Summary of earnings per share (Details) - EUR (€) € / shares in Units, € in Thousands, shares in Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Basic earnings per share [abstract]
(Loss) / Profit from continuing operations attributable to the owners of the parent	€ (11,729)	€ 5,230	€ (26,927)	€ (46,692)
Diluted earnings per share [abstract]
(Loss) / Profit from continuing operations attributable to the owners of the parent	(11,729)	5,230	(26,927)	(46,692)
Ordinary shares
Basic earnings per share [abstract]
(Loss) / Profit from continuing operations attributable to the owners of the parent	€ (9,725)	€ 4,761	€ (23,147)	€ (42,503)
Weighted average number of basic ordinary shares outstanding (in shares)	188,546	179,449	184,818	179,449
Basic earnings / (loss) per share (in euro per share)	€ (0.05)	€ 0.03	€ (0.13)	€ (0.24)
Diluted earnings per share [abstract]
(Loss) / Profit from continuing operations attributable to the owners of the parent	€ (9,725)	€ 4,761	€ (23,147)	€ (42,503)
Weighted average number of diluted ordinary shares outstanding (in shares)	188,546	179,704	184,818	179,449
Diluted earnings / (loss) per share (in euro per share)	€ (0.05)	€ 0.03	€ (0.13)	€ (0.24)
Preference shares
Basic earnings per share [abstract]
(Loss) / Profit from continuing operations attributable to the owners of the parent	€ (2,004)	€ 469	€ (3,780)	€ (4,189)
Weighted average number of basic preference shares outstanding (in shares)	38,861	17,684	30,182	17,684
Basic earnings / (loss) per share (in euro per share)	€ (0.05)	€ 0.03	€ (0.13)	€ (0.24)
Diluted earnings per share [abstract]
(Loss) / Profit from continuing operations attributable to the owners of the parent	€ (2,004)	€ 469	€ (3,780)	€ (4,189)
Weighted average number of diluted preference shares outstanding (in shares)	38,861	17,684	30,182	17,684
Diluted earnings / (loss) per share (in euro per share)	€ (0.05)	€ 0.03	€ (0.13)	€ (0.24)

Adjusted Weighted Average Number Of Preference Shares Outstanding

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Weighted Average Number Of Preference Shares Outstanding

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The weighted average number of ordinary shares outstanding plus the weighted average number of ordinary shares that would be issued on the conversion of all the dilutive potential ordinary shares into ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]]

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The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator) divided by the weighted average number of ordinary shares outstanding during the period (the denominator).

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The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator), divided by the weighted average number of ordinary shares outstanding during the period (the denominator), both adjusted for the effects of all dilutive potential ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]]

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The profit (loss) from continuing operations attributable to ordinary equity holders of the parent entity. [Refer: Continuing operations [member]; Profit (loss) from continuing operations]

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The profit (loss) from continuing operations attributable to ordinary equity holders of the parent entity, adjusted for the effects of all dilutive potential ordinary shares. [Refer: Profit (loss) from continuing operations]

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The number of ordinary shares outstanding at the beginning of the period, adjusted by the number of ordinary shares bought back or issued during the period multiplied by a time-weighting factor.

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