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Borrowings - Summary of Korean Won and Foreign Currency Borrowings (Detail) ₩ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2020 KRW (₩) | Dec. 31, 2020 SGD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 KRW (₩)
Disclosure of detailed information about borrowings [line items] |  |  |  |
Maturity | Jun. 5, 2025 |  |  |
Annual interest rates | 0.00% | 0.00% | 0.00% |
Borrowings | ₩ 7,316,298 | $ 284,000,000 | $ 519,598,989 | ₩ 7,298,867
The 1st CB(Private) Jun. 5, 2020 [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Borrowings | 5,623 |  |  |
Redemption premium | 2,267 |  |  |
Bond discount issuance | (4,644) |  |  |
The 1st CB(Private) Jun. 5, 2020 [member] | The 1st CB(Private) Jun. 5, 2025 [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Borrowings | ₩ 8,000 |  |  |

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