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Related Party Transactions - Summary of Related Parties Outstanding Balances of Receivables and Payables (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Trade receivables [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables | ₩ 2,078 | ₩ 2,249
Trade receivables [member] | K-Realty CR-REITs No.1 [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables | 674 | 778
Trade receivables [member] | MOS GS Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables |  | 17
Trade receivables [member] | MOS Daegu Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables |  | 1
Trade receivables [member] | MOS Chungcheong Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables |  | 1
Trade receivables [member] | MOS Gangnam Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables |  | 6
Trade receivables [member] | MOS GB Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables |  | 17
Trade receivables [member] | MOS BS Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables |  | 34
Trade receivables [member] | MOS Honam Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables |  | 2
Trade receivables [member] | K Bank Inc. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables | 627 | 1,338
Trade receivables [member] | NgeneBio [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables |  | 1
Trade receivables [member] | Others [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables | 777 | 54
Loans and receivables [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables | 44,570 | 2,510
Loans and receivables [member] | K-Realty CR-REITs No.1 [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables | 30,910 |
Loans and receivables [member] | K Bank Inc. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables | 12,435 |
Loans and receivables [member] | NgeneBio [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables |  | 2,510
Loans and receivables [member] | Others [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables | 1,225 |
Other receivables [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables | 4 | 43,369
Other receivables [member] | K-Realty CR-REITs No.1 [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables |  | 33,800
Other receivables [member] | MOS Chungcheong Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables |  | 290
Other receivables [member] | MOS Gangnam Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables |  | 1
Other receivables [member] | MOS GB Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables |  | 1
Other receivables [member] | MOS BS Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables |  | 1
Other receivables [member] | MOS Honam Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables |  | 1
Other receivables [member] | K Bank Inc. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables |  | 7,994
Other receivables [member] | Others [member] |  |
Disclosure of transactions between related parties [line items] |  |
Receivables | 4 | 1,281
Other payables [member] |  |
Disclosure of transactions between related parties [line items] |  |
Payables | 1,412 | 7,536
Other payables [member] | MOS GS Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Payables |  | 392
Other payables [member] | MOS Daegu Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Payables |  | 1,388
Other payables [member] | MOS Chungcheong Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Payables |  | 1,827
Other payables [member] | MOS Gangnam Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Payables |  | 287
Other payables [member] | MOS GB Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Payables |  | 778
Other payables [member] | MOS BS Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Payables |  | 46
Other payables [member] | MOS Honam Co., Ltd. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Payables |  | 384
Other payables [member] | K Bank Inc. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Payables | 296 | 296
Other payables [member] | NgeneBio [member] |  |
Disclosure of transactions between related parties [line items] |  |
Payables |  | 3
Other payables [member] | Others [member] |  |
Disclosure of transactions between related parties [line items] |  |
Payables | ₩ 1,116 | ₩ 2,135

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