Investments in Associates and Joint Ventures - Details of Cumulative Unrecognized Equity Method Losses (Detail) ₩ in Millions	12 Months Ended
Dec. 31, 2018 KRW (₩)
Disclosure of associates [Line Items]
Unrecognized loss (profit)	₩ 14,528
Unrecognized loss (profit), cumulative loss	21,944
Unrecognized change in equity	0
Unrecognized change in equity, cumulative loss	365
Wave City Development Co., Ltd. [member]
Disclosure of associates [Line Items]
Unrecognized loss (profit)	4,434
Unrecognized loss (profit), cumulative loss	6,534
Unrecognized change in equity	0
Daehan Kanggun BcN Co., Ltd. and others [member]
Disclosure of associates [Line Items]
Unrecognized loss (profit)	10,094
Unrecognized loss (profit), cumulative loss	15,410
Unrecognized change in equity	0
Unrecognized change in equity, cumulative loss	₩ 365

The cumulative amount of the unrecognised share of losses of associates if the entity has stopped recognising its share of losses when applying the equity method. [Refer: Associates [member]; Unrecognised share of losses of associates]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2018-01-01
-Paragraph 22
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=12&date=2018-03-01&anchor=para_22_c&doctype=Standard
-URIDate 2018-03-16

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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.

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The amount of the unrecognised share of associates' losses if the entity has stopped recognising its share of losses when applying the equity method. [Refer: Associates [member]]

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- Definition

Cumulative unrecognized change in equity of associates.

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Unrecognized change in equity of associates.

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