Earnings per share - Summary of Earnings per Share (Details) - EUR (€) € / shares in Units, € in Thousands	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Basic earnings per share [abstract]
(Loss) / Profit from continuing operations attributable to the owners of the parent	€ (95,235)	€ (432,972)	€ (3,532)
Diluted earnings per share [abstract]
(Loss) / Profit from continuing operations attributable to the owners of the parent	(95,235)	(432,972)	(3,532)
Ordinary shares
Basic earnings per share [abstract]
(Loss) / Profit from continuing operations attributable to the owners of the parent	€ (86,692)	€ (398,565)	€ (3,532)
Weighted average number of basic ordinary shares outstanding (in thousand of shares)	179,455,000	169,391,000	168,480,000
Basic earnings per share (in euro per share)	€ (0.48)	€ (2.35)	€ (0.02)
Diluted earnings per share [abstract]
(Loss) / Profit from continuing operations attributable to the owners of the parent	€ (86,692)	€ (398,565)	€ (3,532)
Weighted average number of diluted ordinary shares outstanding (in thousand of shares)	179,455,000	169,391,000	168,480,000
Diluted earnings per share (in euro per share)	€ (0.48)	€ (2.35)	€ (0.02)
Preference shares
Basic earnings per share [abstract]
(Loss) / Profit from continuing operations attributable to the owners of the parent	€ (8,543)	€ (34,407)	€ 0
Weighted average number of basic preference shares outstanding (in thousand of shares)	17,684,000	20,656,000	0
Basic earnings per share (in euro per share)	€ (0.48)	€ (1.67)	€ 0
Diluted earnings per share [abstract]
(Loss) / Profit from continuing operations attributable to the owners of the parent	€ (8,543)	€ (34,407)	€ 0
Weighted average number of diluted number of preference shares outstanding (in thousand of shares)	17,684,000	20,656,000	0
Diluted earnings per share (in euro per share)	€ (0.48)	€ (1.67)	€ 0

Adjusted Weighted Average Number Of Preference Shares Outstanding

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Weighted Average Number Of Basic 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]]

+ References

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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) attributable to ordinary equity holders of the parent entity. [Refer: Profit (loss)]

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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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