Business Combinations - Summary of Divestments Transactions (Detail) - Divestments 2022-2024 [member] - SEK (kr) kr in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disclosure Of Divestitures [Line Items]
Cash and cash equivalents	kr 0	kr (633)	kr 20
Shares in associated companies	0	0	298
Proceeds	0	(633)	318
Net assets disposed of
Property, plant and equipment	0	121	0
Investments in associates	0	0	82
Other assets	0	0	23
Provisions, incl. post-employment benefits	0	0	(42)
Other liabilities	(39)	35	(101)
Total net assets	(39)	156	(38)
Net gains/losses from divestments	39	(789)	356
Shares in associated companies	0	0	(298)
Cash flow effect	kr 0	kr (633)	kr 20

Cash proceeds from divestures.

No definition available.

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- Definition

Disclosure Of Divestitures [line items]

+ References

No definition available.

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- Definition

Disposal of provisions including post-employement benefits.

+ References

No definition available.

+ Details

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- Definition

Effect on cash flow due to divestment.

+ References

No definition available.

+ Details

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- Definition

Equity interest received from divestures.

+ References

No definition available.

+ Details

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- Definition

Net Assets Disposal Of [abstract].

+ References

No definition available.

+ Details

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- Definition

Net assets liabilities in subsidiary or businesses disposed.

+ References

No definition available.

+ Details

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- Definition

Proceeds from divestiture.

+ References

No definition available.

+ Details

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- Definition

Adjustments for gain (loss) on disposals investments in subsidiaries, joint ventures and associates to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Total for all associates [member]; Total for all joint ventures [member]; Total for all subsidiaries [member]; Investments in subsidiaries, joint ventures and associates reported in separate financial statements; Profit (loss)]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 7
-IssueDate 2024-01-01
-Paragraph 20
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2024-en-r&anchor=para_20&doctype=Standard
-URIDate 2024-03-27

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- Definition

The amount of assets, other than cash or cash equivalents, in subsidiaries or other businesses over which control is obtained or lost. [Refer: Total for all subsidiaries [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
-IssueDate 2024-01-01
-Paragraph 40
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- Definition

The decrease in property, plant and equipment resulting from disposals. [Refer: Property, plant and equipment]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 16
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-URIDate 2024-03-27

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- Definition

The gains (losses) on disposals of investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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- Definition

The amount of liabilities in subsidiaries or other businesses over which control is obtained or lost. [Refer: Total for all subsidiaries [member]]

+ References

+ Details

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