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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, 2021 | Dec. 31, 2020
Disclosure of detailed information about hedging instruments [line items] |  |
Contract amount | ₩ 2,904,327 | ₩ 2,771,700
Assets | 99,453 | 7,684
Liabilities | 18,126 | 127,929
Changes in fair value to calculate the ineffective portion of hedges | 197,369 | (154,528)
USD |  |
Disclosure of detailed information about hedging instruments [line items] |  |
Foreign currency | 2,016,350 | 1,768,912
Contract amount | 2,322,085 | 2,037,568
Assets | 93,948 | 2,111
Liabilities | 77 | 100,623
Changes in fair value to calculate the ineffective portion of hedges | 186,130 | (136,852)
JPY |  |
Disclosure of detailed information about hedging instruments [line items] |  |
Foreign currency | 30,000,000 | 46,000,000
Contract amount | 326,751 | 488,924
Assets | 0 | 5,573
Liabilities | 18,049 | 13,839
Changes in fair value to calculate the ineffective portion of hedges | (7,199) | (4,065)
SGD |  |
Disclosure of detailed information about hedging instruments [line items] |  |
Foreign currency | 284,000 | 284,000
Contract amount | 245,208 | 245,208
Assets | 5,431 | 0
Liabilities | 0 | 13,467
Changes in fair value to calculate the ineffective portion of hedges | 18,387 | ₩ (13,611)
EUR |  |
Disclosure of detailed information about hedging instruments [line items] |  |
Foreign currency | 7,700 |
Contract amount | 10,283 |
Assets | 74 |
Liabilities | 0 |
Changes in fair value to calculate the ineffective portion of hedges | ₩ 51 |

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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 2021-01-01 -Paragraph 24A -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2021-en-r&anchor=para_24A_c&doctype=Standard -URIDate 2021-03-24 + Details
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- Definition The amount of a hedging instrument, recognised as an asset. [Refer: Hedging instruments [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2021-01-01 -Paragraph 24A -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2021-en-r&anchor=para_24A_a&doctype=Standard -URIDate 2021-03-24 + Details
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- Definition The amount of a hedging instrument, recognised as a liability. [Refer: Hedging instruments [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2021-01-01 -Paragraph 24A -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2021-en-r&anchor=para_24A_a&doctype=Standard -URIDate 2021-03-24 + 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 2021-01-01 -Paragraph 24H -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2021-en-r&anchor=para_24H_e&doctype=Standard -URIDate 2021-03-24 + Details
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