Risk Management - Summary of Reconciliation of Changes in Fair Value Measurement, Assets (Details) - KRW (₩) ₩ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Changes in fair value measurement, assets
Beginning balance	₩ 25,175,820
Ending balance	26,197,311	₩ 25,175,820
At fair value
Changes in fair value measurement, assets
Beginning balance	4,214,122
Ending balance	5,542,186	4,214,122
At fair value \| Financial assets at fair value through profit or loss, category [member]
Changes in fair value measurement, assets
Beginning balance	2,711,285
Ending balance	2,176,172	2,711,285
At fair value \| Financial assets at fair value through other comprehensive income, category [member]
Changes in fair value measurement, assets
Beginning balance	502,443
Ending balance	674,850	502,443
At fair value \| Level 3 \| Financial assets at fair value through profit or loss, category [member] \| Cooperative [member]
Changes in fair value measurement, assets
Beginning balance	6,735	6,329
Acquisition	0	0
Reclassified category	22	270
Valuation	115	136
Disposal	0	0
Foreign currency translation and others	0	0
Ending balance	6,872	6,735
At fair value \| Level 3 \| Financial assets at fair value through other comprehensive income, category [member] \| Unlisted Securities [Member]
Changes in fair value measurement, assets
Beginning balance	212,762	202,243
Acquisition	4,000	9,550
Reclassified category	0	0
Valuation	88,256	5,445
Disposal	0	(5,332)
Foreign currency translation and others	4,691	856
Ending balance	309,709	212,762
At fair value \| Level 3 \| Financial assets at fair value through other comprehensive income, category [member] \| Debt securities [member]
Changes in fair value measurement, assets
Beginning balance	4,627	529
Acquisition	0	4,080
Reclassified category	0	0
Valuation	418	18
Disposal	0	0
Foreign currency translation and others	0	0
Ending balance	₩ 5,045	₩ 4,627

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The amount of assets that are: (a) cash; (b) an equity instrument of another entity; (c) a contractual right: (i) to receive cash or another financial asset from another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially favourable to the entity; or (d) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to receive a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose the entity’s own equity instruments do not include puttable financial instruments classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. [Refer: Classes of financial instruments [domain]; Financial liabilities]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The gains (losses) excluding exchange differences, recognised in other comprehensive income, on the fair value measurement of assets. [Refer: At fair value [member]; Other comprehensive income]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The gains (losses) on exchange differences, recognised in other comprehensive income, on the fair value measurement of assets. [Refer: At fair value [member]; Other comprehensive income]

+ References

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The gains (losses) excluding exchange differences, recognised in profit or loss, on the fair value measurement of assets. [Refer: At fair value [member]]

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The increase in the fair value measurement of assets resulting from purchases of those assets. [Refer: At fair value [member]]

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The decrease in the fair value measurement of assets resulting from sales. [Refer: At fair value [member]]

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The amount of transfers of assets into Level 3 of the fair value hierarchy. [Refer: Level 3 of fair value hierarchy [member]]

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