Financial instruments - Fair values and risk management - Hedge discontinuance and ineffectiveness (Details) - EUR (€) € in Millions	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Disclosure of detailed information about hedging instruments [line items]
Total	€ 266.0	€ 31.0	€ 1,295.0
Cash Flow Hedges
Disclosure of detailed information about hedging instruments [line items]
Change in gross value used for calculating hedge ineffectiveness	€ (1.5)	€ 3,622.4	€ (1,020.9)

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

No definition available.

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- Definition

The gain (loss) on the change in fair value of the hedged item used as a basis for recognising hedge ineffectiveness. Hedge ineffectiveness is the extent to which the changes in the fair value or the cash flows of the hedging instrument are greater or less than those on the hedged item.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

A component of equity representing the accumulated portion of gain (loss) on a hedging instrument that is determined to be an effective hedge for cash flow hedges. [Refer: Cash flow hedges [member]]

+ References

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