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Retained Earnings - Summary of Retained Earnings (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2018 | Dec. 31, 2017 | Jan. 01, 2017 | Dec. 31, 2016 | Jan. 01, 2016
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Miscellaneous equity [abstract] |  |  |  |  |
Legal reserve | ₩ 782,249 | ₩ 782,249 |  |  |
Voluntary reserves | 4,651,362 | 4,651,362 |  |  |
Unappropriated retained earnings | 5,822,458 | 4,527,539 |  |  |
Total | ₩ 11,256,069 | ₩ 9,961,150 | ₩ 9,778,707 | ₩ 9,778,707 | ₩ 9,147,467

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- References No definition available. + Details
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- Definition A component of equity representing the entity's cumulative undistributed earnings or deficit. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 78 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_78_e&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph IG6 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_IG6&doctype=Implementation%20Guidance -URIDate 2018-03-16 + Details
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- Definition Unappropriated retained earnings. + References No definition available. + Details
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