Statement Of Financial Position [Abstract]
| Concept |
As at 2023-12-31 |
As at 2023-12-31 |
As at 2023-12-31 |
As at 2023-12-31 |
As at 2023-12-31 |
As at 2022-12-31 |
As at 2022-12-31 |
As at 2022-12-31 |
As at 2022-12-31 |
As at 2022-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of financial position [abstract] | |||||||||||||||
| Assets [abstract] | |||||||||||||||
| Property, plant and equipment | — | — | — | — |
4,435,000,000
SEK
|
3,901,000,000
SEK
|
— | — | — | — | — | — | — | — | — |
| Deferred tax assets | — | — | — | — |
1,277,000,000
SEK
|
1,040,000,000
SEK
|
— | — | — | — | — | — | — | — | — |
| Cash and cash equivalents | — | — | — | — |
8,152,000,000
SEK
|
7,212,000,000
SEK
|
— | — | — | — |
5,416,000,000
SEK
|
— | — | — | — |
| Assets | — | — | — | — |
6 422,4
SEK
|
6 220,1
SEK
|
— | — | — | — | — | — | — | — | — |
| Equity and liabilities [abstract] | |||||||||||||||
| Equity [abstract] | |||||||||||||||
| Issued capital | — | — | — | — |
12,000,000
SEK
|
12,000,000
SEK
|
— | — | — | — | — | — | — | — | — |
| Retained earnings | — | — | — | — |
1 765,9
SEK
|
1 526,2
SEK
|
— | — | — | — | — | — | — | — | — |
| Other reserves | — | — | — | — |
2,590,000,000
SEK
|
3,132,000,000
SEK
|
— | — | — | — | — | — | — | — | — |
| Equity attributable to owners of parent | — | — | — | — |
2 372,0
SEK
|
2 186,5
SEK
|
— | — | — | — | — | — | — | — | — |
| Equity |
12,000,000
SEK
|
2,590,000,000
SEK
|
1 765,9
SEK
|
3,459,000,000
SEK
|
2 372,0
SEK
|
2 186,5
SEK
|
1 526,2
SEK
|
12,000,000
SEK
|
3,132,000,000
SEK
|
3,459,000,000
SEK
|
1 717,4
SEK
|
1 293,0
SEK
|
3,459,000,000
SEK
|
773,000,000
SEK
|
12,000,000
SEK
|
| Liabilities [abstract] | |||||||||||||||
| Deferred tax liabilities | — | — | — | — |
1,200,000,000
SEK
|
1,190,000,000
SEK
|
— | — | — | — | — | — | — | — | — |
| Liabilities | — | — | — | — |
4 050,4
SEK
|
4 033,6
SEK
|
— | — | — | — | — | — | — | — | — |
| Equity and liabilities | — | — | — | — |
6 422,4
SEK
|
6 220,1
SEK
|
— | — | — | — | — | — | — | — | — |