Statement Of Changes In Equity [Abstract]
| Concept |
As at 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 |
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 |
2020-01-01 to 2020-12-31 |
As at 2020-12-31 |
2020-01-01 to 2020-12-31 |
As at 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 |
1 784
SEK
|
6,000,000
SEK
|
441,000,000
SEK
|
— |
2 252
SEK
|
20,000,000
SEK
|
— | — | — |
1 529
SEK
|
441,000,000
SEK
|
20,000,000
SEK
|
— |
22,000,000
SEK
|
— |
1 968
SEK
|
4,000,000
SEK
|
441,000,000
SEK
|
1 501
SEK
|
1 044
SEK
|
20,000,000
SEK
|
| Changes in equity [abstract] | |||||||||||||||||||||
| Comprehensive income [abstract] | |||||||||||||||||||||
| Profit (loss) | — | — | — | — | — | — |
621,000,000
SEK
|
621,000,000
SEK
|
485,000,000
SEK
|
— | — | — |
485,000,000
SEK
|
— | — | — | — | — | — | — | — |
| Comprehensive income | — | — | — |
28,000,000
SEK
|
— | — |
649,000,000
SEK
|
621,000,000
SEK
|
467,000,000
SEK
|
— | — | — |
485,000,000
SEK
|
— |
18,000,000
SEK
|
— | — | — | — | — | — |
| Dividends recognised as distributions to owners | — | — | — | — | — | — |
168,000,000
SEK
|
168,000,000
SEK
|
— | — | — | — | — | — | — | — | — | — | — | — | — |
| Increase (decrease) through other changes, equity | — | — | — | — | — | — |
3,000,000
SEK
|
3,000,000
SEK
|
— | — | — | — | — | — | — | — | — | — | — | — | — |