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Investment Properties - Summary of Investment Properties Provided as Collateral (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Deposits 1 [Member] | Buildings [member] |  |
Disclosure of detailed information about investment property [line items] |  |
Carrying amount | ₩ 772,708 | ₩ 711,989
Secured amount | ₩ 104,861 | ₩ 98,543
Related account | Deposits | Deposits
Related amount | ₩ 90,150 | ₩ 84,334
Borrowings [Member] | Land and buildings [member] |  |
Disclosure of detailed information about investment property [line items] |  |
Carrying amount | 7,897 | 8,035
Secured amount | ₩ 7,905 | ₩ 7,891
Related account | Borrowings | Borrowings
Related amount | ₩ 5,270 | ₩ 5,260

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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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- Definition Investment property, pledged as security + References No definition available. + Details
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- Details
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- Details
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- Details
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