Statement Of Changes In Equity [Abstract]
| Concept |
2020-04-01 to 2021-03-31 |
2020-04-01 to 2021-03-31 |
2020-04-01 to 2021-03-31 |
2020-04-01 to 2021-03-31 |
2020-04-01 to 2021-03-31 |
2020-04-01 to 2021-03-31 |
2019-04-01 to 2020-03-31 |
2019-04-01 to 2020-03-31 |
2019-04-01 to 2020-03-31 |
2019-04-01 to 2020-03-31 |
2019-04-01 to 2020-03-31 |
2019-04-01 to 2020-03-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | ||||||||||||
| Statement of changes in equity [line items] | ||||||||||||
| Increase (decrease) through transactions with owners, equity |
103,000,000
EUR
|
3,036,000,000
EUR
|
2,299,000,000
EUR
|
635,000,000
EUR
|
1,000,000
EUR
|
2,298,000,000
EUR
|
159,000,000
EUR
|
2,000,000
EUR
|
2,893,000,000
EUR
|
4,288,000,000
EUR
|
2,895,000,000
EUR
|
1,236,000,000
EUR
|
| Purchase of treasury shares | — |
4,000,000
EUR
|
529,000,000
EUR
|
525,000,000
EUR
|
— |
529,000,000
EUR
|
— | — |
1,216,000,000
EUR
|
9,000,000
EUR
|
1,216,000,000
EUR
|
1,207,000,000
EUR
|
| Cancellation of treasury shares | — |
1,160,000,000
EUR
|
— |
1,160,000,000
EUR
|
— | — | — | — | — |
2,435,000,000
EUR
|
— |
2,435,000,000
EUR
|