Risk Management - Summary of Reconciliation of Changes in Fair Value Measurement, Assets (Details) - KRW (₩) ₩ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Changes in fair value measurement, assets
Beginning balance	₩ 23,473,492
Ending balance	25,175,820	₩ 23,473,492
At fair value
Changes in fair value measurement, assets
Beginning balance	5,230,361
Ending balance	4,214,122	5,230,361
At fair value \| Level 3 \| Financial assets at fair value through profit or loss, category [member]
Changes in fair value measurement, assets
Beginning balance	6,329	5,797
Acquisition	0	400
Reclassified category	270	0
Valuation	136	132
Disposal	0	0
Foreign currency translation and others	0	0
Ending balance	6,735	6,329
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	202,243	160,790
Acquisition	9,550	9,451
Reclassified category	0	0
Valuation	5,445	33,237
Disposal	(5,332)	0
Foreign currency translation and others	856	(1,235)
Ending balance	212,762	202,243
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	529	491
Acquisition	4,080	0
Reclassified category	0	0
Valuation	18	38
Disposal	0	0
Foreign currency translation and others	0	0
Ending balance	₩ 4,627	₩ 529

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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: Financial instruments, class [member]; Financial liabilities]

+ References

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

The gains (losses) including 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/2003/role/disclosureRef
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- Definition

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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-Name IFRS
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- Definition

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

+ References

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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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