v3.25.4
Derivatives and hedge accounting - Cash flow hedge reserve (Details) - SEK (kr)
kr in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Reconciliation of Cash Flow Hedge Reserve [Abstract]      
Balance at the beginning of the year [1] kr 24,572 kr 22,846 kr 21,575
Other comprehensive income, net of tax [1] 9 291 27
Total comprehensive income [1],[2] 1,192 1,974 1,271
Balance at the end of the year [1] 24,089 24,572 22,846
Hedge reserve      
Reconciliation of Cash Flow Hedge Reserve [Abstract]      
Balance at the beginning of the year (3) (47) (97)
Valuation gains and losses 6 126  
Tax on valuation gains and losses (1) (26)  
Transferred to the income statement (2) (71)  
Tax on transfers to the income statement 0 15  
Other comprehensive income, net of tax 3 44 50
Total comprehensive income 3 44 50
Balance at the end of the year 0 (3) kr (47)
of which relates to continuing hedges for which hedge accounting is applied 0 (3)  
of which relates to hedging relationships for which hedge accounting is no longer applied kr 0 kr 0  
[1]
1    The entire equity is attributable to the shareholder of the Parent Company.
[2]
1    The entire profit is attributable to the shareholder of the Parent Company.