v3.26.1
Financial instruments - Fair values and risk management - Contractual undiscounted cash flows (Details) - EUR (€)
€ in Millions
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities € 4,473.0 € 5,565.4 € 5,324.2
Derivative financial instruments (2,226.3) (109.8) (352.8)
Derivatives and Non derivatives, contractual undiscounted cash flows 4,505.7 5,681.1 5,502.4
Less than one year      
Disclosure of detailed information about financial instruments [line items]      
Derivative financial instruments (2,133.9) (94.4) (349.5)
Derivatives and Non derivatives, contractual undiscounted cash flows 4,216.6 3,819.2 2,725.8
Later than one year and not later than two years      
Disclosure of detailed information about financial instruments [line items]      
Derivatives and Non derivatives, contractual undiscounted cash flows 50.8 1,259.0 936.6
Later than two years and not later than three years      
Disclosure of detailed information about financial instruments [line items]      
Derivatives and Non derivatives, contractual undiscounted cash flows 33.6 51.0 1,266.6
Later than three years and not later than four years      
Disclosure of detailed information about financial instruments [line items]      
Derivatives and Non derivatives, contractual undiscounted cash flows 163.6 41.0 51.5
Thereafter      
Disclosure of detailed information about financial instruments [line items]      
Derivatives and Non derivatives, contractual undiscounted cash flows 41.1 510.9 521.9
Long and short term debt and lease liabilities      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities 1,491.5 2,682.7 2,746.8
Non-derivative financial liabilities, undiscounted cash flows 1,542.0 2,811.9 2,935.0
Long and short term debt and lease liabilities | Less than one year      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows 1,257.4 939.1 151.7
Long and short term debt and lease liabilities | Later than one year and not later than two years      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows 46.6 1,265.4 936.7
Long and short term debt and lease liabilities | Later than two years and not later than three years      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows 33.3 54.8 1,266.8
Long and short term debt and lease liabilities | Later than three years and not later than four years      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows 163.6 41.3 56.4
Long and short term debt and lease liabilities | Thereafter      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows 41.1 511.3 523.4
Long and short term debt | Fixed rate      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities 1,198.8 2,044.7 2,092.2
Non-derivative financial liabilities, undiscounted cash flows € 1,209.3 € 2,092.0 € 2,172.7
Long and short term debt | Fixed rate | Average      
Disclosure of detailed information about financial instruments [line items]      
Interest rate percentage 0.88% 1.70% 1.67%
Long and short term debt | Fixed rate | Less than one year      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows € 1,209.3 € 882.7 € 85.0
Long and short term debt | Fixed rate | Later than one year and not later than two years      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows   1,209.3 878.3
Long and short term debt | Fixed rate | Later than two years and not later than three years      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows     1,209.4
Long and short term debt | Floating rate      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities 147.8 488.9 490.0
Non-derivative financial liabilities, undiscounted cash flows € 164.8 € 556.3 € 579.2
Long and short term debt | Floating rate | Average      
Disclosure of detailed information about financial instruments [line items]      
Interest rate percentage 2.44% 2.67% 4.30%
Long and short term debt | Floating rate | Less than one year      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows € 3.7 € 13.3 € 21.2
Long and short term debt | Floating rate | Later than one year and not later than two years      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows 3.7 13.4 21.3
Long and short term debt | Floating rate | Later than two years and not later than three years      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows 3.7 13.2 21.3
Long and short term debt | Floating rate | Later than three years and not later than four years      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows 153.7 13.2 21.5
Long and short term debt | Floating rate | Thereafter      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows   503.2 493.9
Lease liabilities - right of use      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities 144.9 149.1 164.6
Non-derivative financial liabilities, undiscounted cash flows 167.9 163.6 183.1
Lease liabilities - right of use | Less than one year      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows 44.4 43.1 45.5
Lease liabilities - right of use | Later than one year and not later than two years      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows 42.9 42.7 37.1
Lease liabilities - right of use | Later than two years and not later than three years      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows 29.6 41.6 36.1
Lease liabilities - right of use | Later than three years and not later than four years      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows 9.9 28.1 34.9
Lease liabilities - right of use | Thereafter      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows 41.1 8.1 29.5
Lease liabilities - right of use | Fixed rate      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities € 144.9 € 149.1 € 164.6
Lease liabilities - right of use | Fixed rate | Average      
Disclosure of detailed information about financial instruments [line items]      
Interest rate percentage 4.89% 4.89% 4.43%
Lease liabilities - right of use | Fixed rate | Less than one year      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities € 39.8 € 37.4 € 39.4
Lease liabilities - right of use | Fixed rate | Later than one year and not later than two years      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities 39.1 37.9 31.9
Lease liabilities - right of use | Fixed rate | Later than two years and not later than three years      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities 27.3 38.8 32.1
Lease liabilities - right of use | Fixed rate | Later than three years and not later than four years      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities 8.6 27.1 32.7
Lease liabilities - right of use | Fixed rate | Thereafter      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities 30.1 7.9 28.5
Foriegn currency forward contracts      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities 79.6 2.7 3.3
Foreign currency forward contract outflows      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities 79.6 2.7 3.3
Derivatives, contractual undiscounted cash flows 2,470.7 508.6 188.3
Foreign currency forward contract outflows | Less than one year      
Disclosure of detailed information about financial instruments [line items]      
Derivatives, contractual undiscounted cash flows 2,297.5 51.6 7.0
Foreign currency forward contract outflows | Later than one year and not later than two years      
Disclosure of detailed information about financial instruments [line items]      
Derivatives, contractual undiscounted cash flows 139.9 327.3 10.6
Foreign currency forward contract outflows | Later than two years and not later than three years      
Disclosure of detailed information about financial instruments [line items]      
Derivatives, contractual undiscounted cash flows 26.6 116.5 10.0
Foreign currency forward contract outflows | Later than three years and not later than four years      
Disclosure of detailed information about financial instruments [line items]      
Derivatives, contractual undiscounted cash flows 6.7 7.0 133.6
Foreign currency forward contract outflows | Thereafter      
Disclosure of detailed information about financial instruments [line items]      
Derivatives, contractual undiscounted cash flows   6.2 27.1
Foreign currency forward contract inflows      
Disclosure of detailed information about financial instruments [line items]      
Derivatives, contractual undiscounted cash flows (2,408.9) (519.4) (195.0)
Foreign currency forward contract inflows | Less than one year      
Disclosure of detailed information about financial instruments [line items]      
Derivatives, contractual undiscounted cash flows (2,240.2) (51.5) (7.0)
Foreign currency forward contract inflows | Later than one year and not later than two years      
Disclosure of detailed information about financial instruments [line items]      
Derivatives, contractual undiscounted cash flows (135.7) (333.7) (10.7)
Foreign currency forward contract inflows | Later than two years and not later than three years      
Disclosure of detailed information about financial instruments [line items]      
Derivatives, contractual undiscounted cash flows (26.3) (120.3) (10.2)
Foreign currency forward contract inflows | Later than three years and not later than four years      
Disclosure of detailed information about financial instruments [line items]      
Derivatives, contractual undiscounted cash flows (6.7) (7.3) (138.5)
Foreign currency forward contract inflows | Thereafter      
Disclosure of detailed information about financial instruments [line items]      
Derivatives, contractual undiscounted cash flows   (6.6) (28.6)
Commodity forward contracts      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities 70.5 224.5 178.8
Derivatives, contractual undiscounted cash flows 70.5 224.5 178.8
Commodity forward contracts | Less than one year      
Disclosure of detailed information about financial instruments [line items]      
Derivatives, contractual undiscounted cash flows 70.5 224.5 178.8
Trade payables      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities 609.8 702.0 792.2
Non-derivative financial liabilities, undiscounted cash flows 609.8 702.0 792.2
Trade payables | Less than one year      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows 609.8 702.0 792.2
Accrued expenses      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities 2,221.6 1,953.5 1,603.1
Non-derivative financial liabilities, undiscounted cash flows 2,221.6 1,953.5 1,603.1
Accrued expenses | Less than one year      
Disclosure of detailed information about financial instruments [line items]      
Non-derivative financial liabilities, undiscounted cash flows 2,221.6 1,953.5 1,603.1
Debt      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities 147.8 1,685.2 2,532.2
Debt | Fixed rate      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities € 1,198.8 € 2,044.7 € 2,092.2
Debt | Fixed rate | Average      
Disclosure of detailed information about financial instruments [line items]      
Interest rate percentage 0.88% 1.70% 1.67%
Debt | Fixed rate | Less than one year      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities € 1,198.8 € 848.4 € 50.0
Debt | Fixed rate | Later than one year and not later than two years      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities   € 1,196.3 843.4
Debt | Fixed rate | Later than two years and not later than three years      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities     € 1,198.8