Statement Of Changes In Equity [Abstract]
| Concept |
2021-01-01 to 2021-12-31 |
2021-01-01 to 2021-12-31 |
2021-01-01 to 2021-12-31 |
2021-01-01 to 2021-12-31 |
2020-01-01 to 2020-12-31 |
2020-01-01 to 2020-12-31 |
2020-01-01 to 2020-12-31 |
|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | |||||||
| Statement of changes in equity [line items] | |||||||
| Increase (decrease) through exercise of options, equity |
1,000,000
SEK
|
443,000,000
SEK
|
444,000,000
SEK
|
— | — | — | — |
| Increase (decrease) through conversion of convertible instruments, equity |
1,000,000
SEK
|
922,000,000
SEK
|
923,000,000
SEK
|
— |
0
SEK
|
23,000,000
SEK
|
23,000,000
SEK
|
| Purchase of treasury shares | — | — |
300,000,000
SEK
|
300,000,000
SEK
|
— |
10,000,000
SEK
|
10,000,000
SEK
|
| Sale or issue of treasury shares | — | — |
371,000,000
SEK
|
371,000,000
SEK
|
— | — | — |