Risk Management - Summary of Reconciliation of Changes in Fair Value Measurement, Assets (Details) - KRW (₩) ₩ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Changes in fair value measurement, assets
Beginning balance	₩ 17,082,664
Valuation	1,032,864	₩ 1,881,382
Ending balance	17,443,120	17,082,664
Financial assets at fair value through profit or loss, category [member]
Changes in fair value measurement, assets
Beginning balance	1,992,146
Ending balance	1,475,891	1,992,146
Financial assets at fair value through other comprehensive income, category [member]
Changes in fair value measurement, assets
Beginning balance	358,559
Ending balance	435,107	358,559
At fair value
Changes in fair value measurement, assets
Valuation	1,032,864	1,881,382
At fair value \| Level 3
Changes in fair value measurement, assets
Valuation	5,797	5,692
At fair value \| Level 3 \| Financial assets at fair value through profit or loss, category [member]
Changes in fair value measurement, assets
Beginning balance	5,692	5,156
Acquisition	0	359
Reclassified category	0	0
Disposal	0	(446)
Valuation	105	623
Gains (losses) recognised in other comprehensive income on exchange differences, fair value measurement, assets	0	0
Ending balance	5,797	5,692
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	163,889	177,968
Acquisition	8,929	2,900
Reclassified category	0	0
Disposal	(13)	(1)
Valuation	(12,335)	(23,128)
Gains (losses) recognised in other comprehensive income on exchange differences, fair value measurement, assets	320	6,150
Ending balance	160,790	163,889
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	0
Acquisition	500
Reclassified category	0
Disposal	0
Valuation	0
Gains (losses) recognised in other comprehensive income on exchange differences, fair value measurement, assets	(9)
Ending balance	₩ 491	₩ 0

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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]

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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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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]

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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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