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Financial Risk Management - Summary of Maximum Exposure to Credit Risk (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2020 | Dec. 31, 2019
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Disclosure of detailed information about financial instruments [line items] |  |
Maximum exposure to credit risk | ₩ 10,731,034 | ₩ 10,873,266
Cash and cash equivalents (except for cash on hand) [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Maximum exposure to credit risk | 2,625,581 | 2,226,608
Financial assets at amortized costs [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Maximum exposure to credit risk | 5,034,621 | 5,784,228
Financial assets at fair value through other comprehensive income [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Maximum exposure to credit risk | 1,118,619 | 1,256,266
Contract assets [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Maximum exposure to credit risk | 586,438 | 557,041
Derivatives financial assets for hedging [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Maximum exposure to credit risk | 7,684 | 58,576
Financial assets at fair value through profit or loss [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Maximum exposure to credit risk | 680,453 | 541,657
Other financial assets at fair value through other comprehensive income [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Maximum exposure to credit risk | 6,570 | 7,086
Other financial assets at amortized costs [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Maximum exposure to credit risk | ₩ 671,068 | ₩ 441,804

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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. + References No definition available. + Details
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- Definition The amount that best represents the maximum exposure to credit risk without taking into account any collateral held or other credit enhancements (for example, netting agreements that do not qualify for offset in accordance with IAS 32). [Refer: Credit risk [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 35K -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_35K_a&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Note Expiry date 2021-01-01 -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 36 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_36_a&doctype=Standard&book=b -URIDate 2020-01-01 + Details
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