Statement Of Changes In Equity [Abstract]
| Concept |
2021-01-01 to 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 |
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 |
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 |
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 |
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 |
As at 2019-12-31 |
As at 2019-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | |||||||||||||||||||||||||||||||
| Statement of changes in equity [line items] | |||||||||||||||||||||||||||||||
| Equity | — |
2 162,1
SEK
|
1,258,000,000
SEK
|
4,444,000,000
SEK
|
— |
2 854,0
SEK
|
— |
2 857,8
SEK
|
38,000,000
SEK
|
1,255,000,000
SEK
|
— | — | — |
1 899,2
SEK
|
138,000,000
SEK
|
1,255,000,000
SEK
|
— |
4,444,000,000
SEK
|
488,000,000
SEK
|
— |
2 517,9
SEK
|
— |
2 504,1
SEK
|
— |
4,444,000,000
SEK
|
1,484,000,000
SEK
|
42,000,000
SEK
|
2 417,4
SEK
|
1 694,9
SEK
|
2 413,2
SEK
|
1,255,000,000
SEK
|
| Changes in equity [abstract] | |||||||||||||||||||||||||||||||
| Comprehensive income [abstract] | |||||||||||||||||||||||||||||||
| Profit (loss) |
55,000,000
SEK
|
— | — | — | — | — |
5,682,000,000
SEK
|
— | — | — |
5,737,000,000
SEK
|
5,682,000,000
SEK
|
3,969,000,000
SEK
|
— | — | — |
3,967,000,000
SEK
|
— | — | — | — |
3,967,000,000
SEK
|
— |
3,000,000
SEK
|
— | — | — | — | — | — | — |
| Other comprehensive income | — | — | — | — |
770,000,000
SEK
|
— |
770,000,000
SEK
|
— | — | — |
770,000,000
SEK
|
— |
996,000,000
SEK
|
— | — | — | — | — | — |
996,000,000
SEK
|
— |
996,000,000
SEK
|
— | — | — | — | — | — | — | — | — |
| Comprehensive income | — | — | — | — | — | — | — | — | — | — |
6,507,000,000
SEK
|
— |
2,974,000,000
SEK
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Dividends recognised as distributions to owners | — | — | — | — | — | — |
1,808,000,000
SEK
|
— | — | — |
1,808,000,000
SEK
|
1,808,000,000
SEK
|
1,507,000,000
SEK
|
— | — | — |
1,507,000,000
SEK
|
— | — | — | — |
1,507,000,000
SEK
|
— | — | — | — | — | — | — | — | — |