Earnings per Share - Summary of Basic Earnings Per Share (Detail) - KRW (₩) ₩ / shares in Units, ₩ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Basic earnings per share attributable to owners of the Parent Company:
Profit attributable to owners of the Parent Company	₩ 3,127,887	₩ 2,599,829	₩ 1,675,967
Interest on hybrid bonds	(15,803)	(16,840)	(16,840)
Profit attributable to owners of the Parent Company on common shares	₩ 3,112,084	₩ 2,582,989	₩ 1,659,127
Weighted average number of common shares outstanding	70,622,976	70,609,160	70,609,160
Basic earnings per share (in won)	₩ 44,066	₩ 36,582	₩ 23,497

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).

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The profit (loss) attributable to ordinary equity holders of the parent equity. [Refer: Profit (loss)]

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The profit (loss) from continuing and discontinued operations attributable to owners of the parent. [Refer: Profit (loss)]

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The number of ordinary shares outstanding at the beginning of the period, adjusted by the number of ordinary shares bought back or issued during the period multiplied by a time-weighting factor.

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Interest on hybrid bonds.

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