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Commitments and Contingencies - Summary of Guarantees Received from Financial Institutions (Detail) - Dec. 31, 2017 zł in Thousands, $ in Thousands, ₩ in Millions | KRW (₩) | USD ($) | PLN (zł)
--- | --- | --- | ---
Disclosure of detailed information about borrowings [Line Items] |  |  |
Limit | ₩ 681,280 | $ 69,141 | zł 23,000
Performance guarantee [Member] | Seoul Guarantee Insurance and others [Member] |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |
Limit | 116,787 | 1,275 |
Guarantee for import letters of credit [Member] | Industrial Bank of Korea and others [Member] |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |
Limit | $ |  | 5,980 |
Guarantee for payment in foreign currency [Member] | KEB Hana Bank and others [Member] |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |
Limit |  | 54,072 | zł 23,000
Guarantee for advances received [Member] | Export-Import Bank of Korea [Member] |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |
Limit | $ |  | 7,414 |
Comprehensive credit line [Member] | KEB Hana Bank and others [Member] |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |
Limit | 55,000 |  |
Bid guarantee [Member] | KEB Hana Bank [member] |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |
Limit | $ |  | $ 400 |
Bid guarantee [Member] | Korea Software Financial Cooperative [Member] |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |
Limit | 96,911 |  |
Performance guarantee/Warrant guarantee [Member] | Korea Software Financial Cooperative [Member] |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |
Limit | 302,062 |  |
Guarantee for advances received/Others [Member] | Korea Software Financial Cooperative and others [Member] |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |
Limit | 99,228 |  |
Warrant guarantee [Member] | Seoul Guarantee Insurance [Member] |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |
Limit | 2,962 |  |
Guarantees for licensing [Member] | Seoul Guarantee Insurance [Member] |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |
Limit | 4,077 |  |
Guarantees for public sale [Member] | Seoul Guarantee Insurance [Member] |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |
Limit | 50 |  |
Guarantees for deposits [Member] | Seoul Guarantee Insurance and others [Member] |  |  |
Disclosure of detailed information about borrowings [Line Items] |  |  |
Limit | ₩ 4,203 |  |

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