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Earnings per Share - Summary of Basic and Diluted Earnings per Share from Operations (Detail) - KRW (₩) ₩ / shares in Units, ₩ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Basic earnings per share [abstract] |  |  |
Profit (loss) attributable to ordinary shares | ₩ 461,559 | ₩ 708,362 | ₩ 546,361
Profit from continuing operations attributable to ordinary shares | ₩ 461,559 | ₩ 708,362 | 404,045
Profit from discontinued operations attributable to ordinary shares |  |  | ₩ 142,316
Weighted average number of ordinary shares outstanding | 245,017,175 | 244,892,313 | 244,854,364
Basic earnings per share (In Korean won) | ₩ 1,884 | ₩ 2,893 | ₩ 2,231
Basic earnings per share from continuing operations | ₩ 1,884 | ₩ 2,893 | 1,650
Basic earnings per share from discontinued operations |  |  | ₩ 581
Profit attributable to ordinary shares (In millions of Korean won) | ₩ 461,559 | ₩ 708,362 | ₩ 546,361
Adjusted net income attributable to ordinary shares |  | (67) | (75)
Diluted profit attributable to ordinary shares (In millions of Korean won) | 461,559 | 708,295 | 546,286
Diluted profit (loss) attributable to ordinary shares | 461,559 | 708,295 | 546,286
Diluted profit from continuing operations attributable to ordinary shares | ₩ 461,559 | ₩ 708,295 | 403,970
Diluted income from discontinued operations attributable to ordinary shares |  |  | ₩ 142,316
Number of dilutive potential ordinary shares outstanding | 79,880 | 84,245 | 1,104
Weighted average number of ordinary shares outstanding | 245,097,055 | 244,976,558 | 244,855,468
Diluted earnings per share (In Korean won) | ₩ 1,883 | ₩ 2,891 | ₩ 2,231
Diluted earnings per share from continuing operations | ₩ 1,883 | ₩ 2,891 | 1,650
Diluted earnings per share from discontinued operations |  |  | ₩ 581

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- Definition The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator) divided by the weighted average number of ordinary shares outstanding during the period (the denominator). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2017-01-01 -Paragraph 66 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=33&date=2017-03-01&anchor=para_66&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition Basic earnings (loss) per share from discontinued operations. [Refer: Basic earnings (loss) per share; Discontinued operations [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2017-01-01 -Paragraph 68 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=33&date=2017-03-01&anchor=para_68&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator), divided by the weighted average number of ordinary shares outstanding during the period (the denominator), both adjusted for the effects of all dilutive potential ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2017-01-01 -Paragraph 66 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=33&date=2017-03-01&anchor=para_66&doctype=Standard -URIDate 2017-03-09 + Details
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