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 |
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 |
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 |
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 2020-12-31 |
2020-01-01 to 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 |
As at 2019-12-31 |
As at 2019-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | |||||||||||||||||||||||||||||||||||
| Statement of changes in equity [line items] | |||||||||||||||||||||||||||||||||||
| Equity | — |
3,947,000,000
SEK
|
4 790,6
SEK
|
— |
5 256,3
SEK
|
— |
5 211,9
SEK
|
444,000,000
SEK
|
— |
229,000,000
SEK
|
37,000,000
SEK
|
— | — | — | — |
1,113,000,000
SEK
|
358,000,000
SEK
|
2 667,4
SEK
|
2 787,2
SEK
|
32,000,000
SEK
|
— |
53,000,000
SEK
|
— | — |
2 823,0
SEK
|
— | — | — |
2 889,7
SEK
|
354,000,000
SEK
|
147,000,000
SEK
|
2 667,4
SEK
|
2 925,1
SEK
|
2,043,000,000
SEK
|
32,000,000
SEK
|
| Changes in equity [abstract] | |||||||||||||||||||||||||||||||||||
| Comprehensive income [abstract] | |||||||||||||||||||||||||||||||||||
| Profit (loss) |
99,000,000
SEK
|
— | — |
4 80,9
SEK
|
— | — | — | — | — | — | — | — |
4,908,000,000
SEK
|
4,809,000,000
SEK
|
4,203,000,000
SEK
|
— | — | — | — | — |
415 ,1
SEK
|
— | — | — | — | — |
51,000,000
SEK
|
4,151,000,000
SEK
|
— | — | — | — | — | — | — |
| Other comprehensive income |
7,000,000
SEK
|
— | — |
176,000,000
SEK
|
— |
176,000,000
SEK
|
— | — | — | — | — | — |
183,000,000
SEK
|
— |
110,000,000
SEK
|
— | — | — | — | — | — | — | — | — | — |
95,000,000
SEK
|
15,000,000
SEK
|
95,000,000
SEK
|
— | — | — | — | — | — | — |
| Comprehensive income |
106,000,000
SEK
|
— | — |
4,985,000,000
SEK
|
— |
176,000,000
SEK
|
— | — |
-
SEK
|
— | — |
-
SEK
|
5,091,000,000
SEK
|
4,809,000,000
SEK
|
4,093,000,000
SEK
|
— | — | — | — | — |
4,151,000,000
SEK
|
— |
-
SEK
|
-
SEK
|
— |
95,000,000
SEK
|
3 ,6
SEK
|
40 5,7
SEK
|
— | — | — | — | — | — | — |
| Increase (decrease) through changes in ownership interests in subsidiaries that do not result in loss of control, equity | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
11, 9
SEK
|
— | — | — | — | — |
102,000,000
SEK
|
— | — | — | — | — |
16,000,000
SEK
|
102,000,000
SEK
|
— | — | — | — | — | — | — |