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Investment Properties - Summary of Investment Properties Provided as Collateral (Detail) - Land and buildings [member] - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Deposits 1 [member] |  |
Disclosure of detailed information about investment property [line items] |  |
Carrying amount | ₩ 548,567 | ₩ 583,778
Secured amount | ₩ 66,551 | ₩ 74,963
Related account | Deposits | Deposits
Related amount | ₩ 59,492 | ₩ 63,923
Borrowings [member] |  |
Disclosure of detailed information about investment property [line items] |  |
Carrying amount | 5,292 | 7,897
Secured amount | ₩ 3,987 | ₩ 7,905
Related account | Borrowings | Borrowings
Related amount | ₩ 3,322 | ₩ 5,270

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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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- Details
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- Details
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