Statement Of Changes In Equity [Abstract]
| Concept |
2021-01-01 to 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
2021-01-01 to 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
2021-01-01 to 2021-12-31 |
2021-01-01 to 2021-12-31 |
2020-01-01 to 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
2020-01-01 to 2020-12-31 |
As at 2020-12-31 |
2020-01-01 to 2020-12-31 |
2020-01-01 to 2020-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | |||||||||||||||||||||||||
| Statement of changes in equity [line items] | |||||||||||||||||||||||||
| Equity | — |
1,647,300,000
SEK
|
1,275,600,000
SEK
|
— |
3,303,900,000
SEK
|
3,276,500,000
SEK
|
27,400,000
SEK
|
353,600,000
SEK
|
— | — | — |
1,257,700,000
SEK
|
20,900,000
SEK
|
1,275,600,000
SEK
|
2,887,000,000
SEK
|
353,600,000
SEK
|
— |
2,907,800,000
SEK
|
— | — |
2,777,000,000
SEK
|
1,275,600,000
SEK
|
2,777,000,000
SEK
|
1,147,700,000
SEK
|
353,600,000
SEK
|
| Changes in equity [abstract] | |||||||||||||||||||||||||
| Comprehensive income [abstract] | |||||||||||||||||||||||||
| Profit (loss) |
8,700,000
SEK
|
— | — |
322,300,000
SEK
|
— | — | — | — |
331,100,000
SEK
|
322,300,000
SEK
|
291,900,000
SEK
|
— | — | — | — | — |
287,100,000
SEK
|
— |
4,800,000
SEK
|
287,100,000
SEK
|
— | — | — | — | — |
| Other comprehensive income |
300,000
SEK
|
— | — |
176,800,000
SEK
|
— | — | — | — |
177,100,000
SEK
|
176,800,000
SEK
|
218,700,000
SEK
|
— | — | — | — | — |
217,600,000
SEK
|
— |
1,100,000
SEK
|
217,600,000
SEK
|
— | — | — | — | — |
| Comprehensive income | — | — | — | — | — | — | — | — |
508,200,000
SEK
|
— |
73,200,000
SEK
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Dividends recognised as distributions to owners |
2,500,000
SEK
|
— | — |
109,600,000
SEK
|
— | — | — | — |
112,100,000
SEK
|
109,600,000
SEK
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Increase (decrease) through changes in ownership interests in subsidiaries that do not result in loss of control, equity | — | — | — | — | — | — | — | — | — | — |
57,500,000
SEK
|
— | — | — | — | — |
40,500,000
SEK
|
— |
17,200,000
SEK
|
40,500,000
SEK
|
— | — | — | — | — |