Business combination - Summary of the net cash outflows due to business combination (Details) ₩ in Millions	Dec. 31, 2025 KRW (₩)
ABL Life Insurance Co Ltd [Member]
Net Cash Outflows Due To Business Combination [Line Items]
Consideration paid in cash	₩ 264,946
Cash and cash equivalents acquired	327,090
Less: Total	62,144
Tongyang Life Insurance Co Ltd [Member]
Net Cash Outflows Due To Business Combination [Line Items]
Consideration paid in cash	1,281,963
Cash and cash equivalents acquired	286,417
Less: Total	₩ 995,546

The fair value, at acquisition date, of cash transferred as consideration in a business combination. [Refer: Total for all business combinations [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2025-01-01
-Paragraph B64
-Subparagraph f
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2025-en-r&anchor=para_B64_f_i&doctype=Appendix&subtype=B
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 35
-Subparagraph e
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_35_e_i&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 35
-Subparagraph e
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_35_e_i&doctype=Standard
-URIDate 2025-03-27

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