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Other Financial Assets and Liabilities - Summary of Hedging instruments (Detail) - Derivatives [member] - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023
Disclosure of detailed information about hedging instruments [line items] |  |
Contract amount | ₩ 2,788,941 | ₩ 2,672,113
Assets | 445,471 | 159,211
Liabilities | 3 | 24,547
Changes in fair value to calculate the ineffective portion of hedges | 363,978 | 45,339
USD |  |
Disclosure of detailed information about hedging instruments [line items] |  |
Foreign currency | 2,150,937 | 2,011,509
Contract amount | 2,658,775 | 2,417,473
Assets | 444,786 | 157,681
Liabilities | 0 | 23,465
Changes in fair value to calculate the ineffective portion of hedges | 362,588 | 44,413
JPY |  |
Disclosure of detailed information about hedging instruments [line items] |  |
Foreign currency |  | 400,000
Contract amount |  | 4,357
Assets |  | 0
Liabilities |  | 660
Changes in fair value to calculate the ineffective portion of hedges |  | (162)
EUR |  |
Disclosure of detailed information about hedging instruments [line items] |  |
Foreign currency | 6,900 | 7,700
Contract amount | 10,166 | 10,283
Assets | 333 | 0
Liabilities | 0 | 231
Changes in fair value to calculate the ineffective portion of hedges | 548 | 381
KRW |  |
Disclosure of detailed information about hedging instruments [line items] |  |
Foreign currency | 0 | 0
Contract amount | 120,000 | 240,000
Assets | 352 | 1,530
Liabilities | 3 | 191
Changes in fair value to calculate the ineffective portion of hedges | ₩ 842 | ₩ 707

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- Definition The gain (loss) on the change in fair value of the hedging instrument used as a basis for recognising hedge ineffectiveness. Hedge ineffectiveness is the extent to which the changes in the fair value or the cash flows of the hedging instrument are greater or less than those on the hedged item. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph 24A -Subparagraph c -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_24A_c&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of a hedging instrument, recognised as an asset. [Refer: Hedging instruments [domain]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph 24A -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_24A_a&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of a hedging instrument, recognised as a liability. [Refer: Hedging instruments [domain]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph 24A -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_24A_a&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The nominal amount of the hedging instruments in hedging relationships to which the entity is applying the exceptions in the scope of the amendments for interest rate benchmark reform. [Refer: Nominal amount of hedging instrument] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph 24H -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_24H_e&doctype=Standard -URIDate 2024-03-27 + Details
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