Earnings (Loss) Per Share Attributable to Owners of the Controlling Company - Summary of Basic Earnings per Share (Detail) - KRW (₩) ₩ / shares in Units, ₩ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Basic earnings per share [abstract]
Profit (loss) attributable to owners of the Controlling Company	₩ (2,829,705)	₩ (207,239)	₩ 1,802,756
Weighted-average number of common stocks outstanding	357,815,700	357,815,700	357,815,700
Earnings (loss) per share	₩ (7,908)	₩ (579)	₩ 5,038

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).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

+ References

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