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Fair Value - Summary of Available-for-sale Financial Assets Measured at Cost (Detail) - Available-for-sale [member] - KRW (₩) ₩ in Millions | Dec. 31, 2017 | Dec. 31, 2016
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Disclosure of fair value measurement of assets [Line Items] |  |
Available-for-sale financial assets measured at cost | ₩ 61,551 | ₩ 105,773
K- Bank [Member] |  |
Disclosure of fair value measurement of assets [Line Items] |  |
Available-for-sale financial assets measured at cost |  | 36,500
IBK-AUCTUS Green Growth Private Equity Fund [Member] |  |
Disclosure of fair value measurement of assets [Line Items] |  |
Available-for-sale financial assets measured at cost | 8,518 | 9,506
CBC II Fund [Member] |  |
Disclosure of fair value measurement of assets [Line Items] |  |
Available-for-sale financial assets measured at cost | 4,670 | 4,710
TRANSLINK No.2 Fund [Member] |  |
Disclosure of fair value measurement of assets [Line Items] |  |
Available-for-sale financial assets measured at cost | 9,395 | 9,395
WALDEN No.6 Fund [Member] |  |
Disclosure of fair value measurement of assets [Line Items] |  |
Available-for-sale financial assets measured at cost | 8,453 | 7,550
Storm IV Fund [Member] |  |
Disclosure of fair value measurement of assets [Line Items] |  |
Available-for-sale financial assets measured at cost | 7,298 | 8,601
Others [Member] |  |
Disclosure of fair value measurement of assets [Line Items] |  |
Available-for-sale financial assets measured at cost | ₩ 23,217 | ₩ 29,511

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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 The amount of financial assets at amortised cost. The amortised cost is the amount at which financial assets are measured at initial recognition minus principal repayments, plus or minus the cumulative amortisation using the effective interest method of any difference between that initial amount and the maturity amount, and adjusted for any impairment. [Refer: Financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2018-01-01 -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 8 -Subparagraph f -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_8_f&doctype=Standard -URIDate 2017-03-09 + Details
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