Risk Management - Summary of Reconciliation of Changes in Fair Value Measurement, Assets (Details) - KRW (₩) ₩ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Changes in fair value measurement, assets
Beginning balance	₩ 17,443,120
Valuation	3,709,508	₩ 1,032,864
Ending balance	23,473,492	17,443,120
Financial assets at fair value through profit or loss, category [member]
Changes in fair value measurement, assets
Beginning balance	1,475,891
Ending balance	4,402,580	1,475,891
Financial assets at fair value through other comprehensive income, category [member]
Changes in fair value measurement, assets
Beginning balance	435,107
Ending balance	502,829	435,107
At fair value
Changes in fair value measurement, assets
Beginning balance	2,115,754
Valuation	3,709,508	1,032,864
Ending balance	5,230,361	2,115,754
At fair value \| Level 3
Changes in fair value measurement, assets
Valuation	6,329	5,797
At fair value \| Level 3 \| Financial assets at fair value through profit or loss, category [member]
Changes in fair value measurement, assets
Beginning balance	5,797	5,692
Acquisition	400	0
Reclassified category	0	0
Disposal	0	0
Valuation	132	105
Foreign currency translation and others	0	0
Ending balance	6,329	5,797
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	160,790	163,889
Acquisition	9,451	8,929
Reclassified category	0	0
Disposal	0	(13)
Valuation	33,237	(12,335)
Foreign currency translation and others	(1,235)	320
Ending balance	202,243	160,790
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	491	0
Acquisition	0	500
Reclassified category	0	0
Disposal	0	0
Valuation	38	0
Foreign currency translation and others	0	(9)
Ending balance	₩ 529	₩ 491

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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

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The amount of financial assets that are measured at fair value and for which gains (losses) are recognised in profit or loss. A financial asset shall be measured at fair value through profit or loss unless it is measured at amortised cost or at fair value through other comprehensive income. A gain (loss) on a financial asset measured at fair value shall be recognised in profit or loss unless it is part of a hedging relationship, it is an investment in an equity instrument for which the entity has elected to present gains and losses in other comprehensive income or it is a financial asset measured at fair value through other comprehensive income. [Refer: At fair value [member]; Financial assets]

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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

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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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- Definition

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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