Other Financial Assets and Liabilities - Summary of Financial Assets at Fair Value Through Profit or Loss (Detail) - KRW (₩) ₩ in Millions	Dec. 31, 2020	Dec. 31, 2019
Disclosure of financial assets [line items]
Equity Instruments	₩ 809,919	₩ 632,324
Less: non-current	(276,109)	(219,026)
Current	533,810	413,298
Equity Instruments Listed [member]
Disclosure of financial assets [line items]
Equity Instruments	46,449	232
Equity Instruments Unlisted [member]
Disclosure of financial assets [line items]
Equity Instruments	83,017	90,357
Debt securities [member]
Disclosure of financial assets [line items]
Equity Instruments	₩ 680,453	541,657
Derivatives held for trading [member]
Disclosure of financial assets [line items]
Equity Instruments		₩ 78

The amount of current financial assets measured at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2020-01-01
-Paragraph 8
-Subparagraph a
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-URIDate 2020-01-01

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

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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 amount of non-current financial assets measured at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss]

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