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Borrowings - Summary of Short-term Borrowing (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 0.00% |
Short-term borrowings | ₩ 95,789 | ₩ 83,500
NongHyup Bank [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Short-term borrowings | 40,189 | 15,000
Shinhan Bank [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Short-term borrowings | 22,500 | 57,500
Korea Development Bank [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Short-term borrowings | 10,000 | 10,000
SooHyup Bank [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Short-term borrowings |  | ₩ 1,000
Woori Bank [Member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Short-term borrowings | 1,900 |
Industrial Bank Of Korea [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Short-term borrowings | 200 |
Hana Bank [Member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Short-term borrowings | ₩ 11,000 |
Short-term borrowings [member] | NongHyup Bank [member] | Bottom of range [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 1.74% |
Short-term borrowings [member] | NongHyup Bank [member] | Top of range [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 2.36% |
Short-term borrowings [member] | Shinhan Bank [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 1.431% |
Annual interest rates description | CD91+1.431% |
Short-term borrowings [member] | Shinhan Bank [member] | Bottom of range [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 2.46% |
Short-term borrowings [member] | Shinhan Bank [member] | Top of range [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 2.96% |
Short-term borrowings [member] | Korea Development Bank [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 3.34% |
Short-term borrowings [member] | Woori Bank [Member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 3.57% |
Short-term borrowings [member] | Industrial Bank Of Korea [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 1.74% |
Short-term borrowings [member] | Hana Bank [Member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Annual interest rates | 4.20% |

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- Definition The basis (reference rate) used for calculation of the interest rate on borrowings. [Refer: Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 7 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_7&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The amount of current borrowings. [Refer: Borrowings] + 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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