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Commitments and Contingencies - Summary of Guarantees Received from Financial Institutions (Detail) - Dec. 31, 2018 zł in Thousands, $ in Thousands, ₩ in Millions | KRW (₩) | PLN (zł) | USD ($)
--- | --- | --- | ---
Disclosure of detailed information about borrowings [line items] |  |  |
Guarantees limit | ₩ 910,105 | zł 23,000 | $ 69,346
Performance guarantee [member] | Seoul Guarantee Insurance and others [member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Guarantees limit | 299,689 |  | 1,200
Guarantee for import letters of credit [member] | Industrial Bank of Korea and others [member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Guarantees limit | $ |  |  | 5,980
Guarantee for payment in korean currency [member] | Shinhan Bank and others [member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Guarantees limit | 5 |  |
Guarantee for payment in foreign currency [member] | KEB Hana Bank and others [member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Guarantees limit |  | zł 23,000 | 51,766
Comprehensive credit line [member] | KEB Hana Bank and others [member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Guarantees limit | 40,000 |  |
Comprehensive credit line [member] | KEB Hana Bank [member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Guarantees limit | $ |  |  | 10,000
Bid guarantee [member] | KEB Hana Bank [member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Guarantees limit | 58,992 |  | $ 400
Bid guarantee [member] | Korea Software Financial Cooperative and others [Member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Guarantees limit | 350 |  |
Performance guarantee/Warrant guarantee [member] | Korea Software Financial Cooperative and others [Member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Guarantees limit | 376,420 |  |
Performance guarantee/Warrant guarantee [member] | Seoul guarantee insurance [member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Guarantees limit | 996 |  |
Guarantee for advances received/others [member] | Korea Software Financial Cooperative and others [Member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Guarantees limit | 124,901 |  |
Warrant guarantee [member] | Korea Software Financial Cooperative and others [Member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Guarantees limit | 1,037 |  |
Guarantees for licensing [member] | Korea Software Financial Cooperative and others [Member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Guarantees limit | 4,070 |  |
Guarantees for public sale [member] | Seoul guarantee insurance [member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Guarantees limit | 120 |  |
Guarantees for deposits [member] | Seoul guarantee insurance [member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Guarantees limit | ₩ 3,525 |  |

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