Other Financial Assets and Liabilities - Summary of Financial Assets at Fair Value Through Profit or Loss (Detail) - KRW (₩) ₩ in Millions	Dec. 31, 2019	Dec. 31, 2018
Disclosure of financial assets [line items]
Equity Instruments	₩ 632,324	₩ 777,685
Less: non-current	(556,147)	(269,148)
Current	413,298	508,537
Equity Instruments Listed [member]
Disclosure of financial assets [line items]
Equity Instruments	232	121
Equity Instruments Unlisted [member]
Disclosure of financial assets [line items]
Equity Instruments	90,357	62,911
Debt securities [member]
Disclosure of financial assets [line items]
Equity Instruments	541,657	₩ 714,653
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 2019-01-01
-Paragraph 8
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2019-en-r&anchor=para_8_a&doctype=Standard
-URIDate 2019-03-27

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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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