Derivatives and hedge accounting - Carrying amount of hedged items in fair value hedges (Details) - of which in fair value hedges - SEK (kr) kr in Millions	Dec. 31, 2025	Dec. 31, 2024
Disclosure of detailed information about hedged items [line items]
Book value, assets	kr 27,914	kr 29,352
Fair value hedge adjustments, assets	(183)	(642)
Book value, liabilities	223,952	256,459
Fair value hedge adjustments, liabilities	1,556	378
Loans in the form of interest-bearing securities
Disclosure of detailed information about hedged items [line items]
Book value, assets	13,333	15,979
Fair value hedge adjustments, assets	(155)	(598)
Loans to credit institutions
Disclosure of detailed information about hedged items [line items]
Book value, assets	874	1,058
Fair value hedge adjustments, assets	(2)
Loans to the public
Disclosure of detailed information about hedged items [line items]
Book value, assets	13,707	12,315
Fair value hedge adjustments, assets	(26)	(44)
Debt securities issued
Disclosure of detailed information about hedged items [line items]
Book value, liabilities	223,952	256,459
Fair value hedge adjustments, liabilities	kr 1,556	kr 378

The accumulated amount of fair value hedge adjustment on a hedged item that is included in the carrying amount of the hedged item, recognised in the statement of financial position as an asset. [Refer: Hedged items [domain]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-IssueDate 2025-01-01
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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No definition available.

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The amount of a hedged item, recognised as an asset. [Refer: Hedged items [domain]]

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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