Earnings per shares - Additional Information (Details) - EUR (€) € / shares in Units, € in Millions	12 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Basic and diluted earnings per share, amount	€ 11,838	€ 2,237	€ 59
Basic earnings per share	€ 0.4277	€ 0.0771	€ 0.0020
Diluted earnings per share	€ 0.4262	€ 0.0768	€ 0.0020
Increase Decrease Due to Changes In Accounting Policy and Corrections of Prior Period Errors [Member]
Basic and diluted earnings per share, amount		€ 149	€ (53)
Basic earnings per share		€ 0.0051	€ 0.0018
Diluted earnings per share		€ 0.0051	€ 0.0018

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, adjusted for the effects of all dilutive potential ordinary shares. [Refer: Profit (loss) from continuing operations]

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