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Commitments and Contingencies - Summary of Guarantees Received from Financial Institutions (Detail) - Dec. 31, 2020 $ in Thousands, ₩ in Millions | KRW (₩) | USD ($)
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Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | ₩ 1,205,141 | $ 72,045
Performance guarantee [member] | Seoul Guarantee Insurance and others [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | 208,386 |
Performance guarantee [member] | Korea Development Bank and others [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | $ |  | 8,569
Performance guarantee [member] | Seoul guarantee insurance [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | 9,690 |
Guarantee for import letters of credit [member] | Industrial Bank of Korea and others [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | $ |  | 5,000
Guarantee for payment in foreign currency [member] | KEB Hana Bank and others [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | $ |  | 40,840
Comprehensive credit line [member] | KEB Hana Bank and others [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | 41,100 | 8,700
Bid guarantee [member] | KEB Hana Bank [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | $ |  | 400
Bid guarantee [member] | Korea Software Financial Cooperative and others [Member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | 80,246 |
Performance guarantee/Warrant guarantee [member] | Korea Software Financial Cooperative and others [Member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | 393,019 |
Guarantee for advance payments/others [member] | Korea Software Financial Cooperative and others [Member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | 388,656 |
Guarantees for licensing [member] | Seoul guarantee insurance [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | 7,748 |
Warranty guarantee [member] | Seoul guarantee insurance [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | 1,305 |
Merchant business guarantee insurance [member] | Seoul guarantee insurance [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | 237 |
Guarantee for payment in won currency [Member] | Shinhan Bank and others [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | 70,962 |
Refund guarantee for advances received [Member] | Korea Development Bank [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | $ |  | $ 8,536
Guarantees for depositions [Member] | Seoul guarantee insurance [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Guarantees limit | ₩ 3,792 |

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