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Borrowings - Summary of Borrowings (Parenthetical) (Detail) ₩ in Millions | Dec. 31, 2020 KRW (₩) | Dec. 31, 2020 SGD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 KRW (₩)
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Disclosure of detailed information about borrowings [line items] |  |  |  |
Borrowings | ₩ 7,316,298 | $ 284,000,000 | $ 519,598,989 | ₩ 7,298,867
Libor rate | 0.238% | 0.238% | 0.238% |
SOR rate | 0.185% | 0.185% | 0.185% |
Medium Term Note Programme [member] | Fixed interest rate [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Borrowings |  |  | $ 100,000,000 |
Medium Term Note Programme [member] | Top of range [member] | Fixed interest rate [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Borrowings |  |  | $ 2,000,000,000 |

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- Definition The amount of outstanding funds that the entity is obligated to repay. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_55&doctype=Standard -URIDate 2020-01-01 + Details
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