Earnings per Share - Summary of Basic and Diluted Earnings per Share from Operations (Detail) - KRW (₩) ₩ / shares in Units, ₩ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Basic earnings per share [abstract]
Profit (loss) attributable to ordinary shares of owners of the Controlling Company	₩ 1,259,686	₩ 1,354,537	₩ 700,889
Weighted average number of ordinary shares outstanding	242,235,332	235,201,782	245,207,307
Basic earnings per share (In Korean won)	₩ 5,200	₩ 5,759	₩ 2,858
Profit attributable to ordinary shares of owners of the Controlling Company (In millions of Korean won)	₩ 1,259,686	₩ 1,354,537	₩ 700,889
Adjustment to net income attributable to ordinary shares (in millions of Korean won)	(496)	0	0
Diluted profit attributable to ordinary shares (In millions of Korean won)	₩ 1,259,190	₩ 1,354,537	₩ 700,889
Number of dilutive potential ordinary shares outstanding	91,931	483,760	69,598
Weighted average number of ordinary shares outstanding	242,327,263	235,685,542	245,276,905
Diluted earnings per share (In Korean won)	₩ 5,196	₩ 5,747	₩ 2,858

The weighted average number of ordinary shares outstanding plus the weighted average number of ordinary shares that would be issued on the conversion of all the dilutive potential ordinary shares into ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]]

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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 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]]

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The number of dilutive potential ordinary shares that relate to the assumed conversion of the entity's convertible instruments.

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

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The profit (loss) attributable to ordinary equity holders of the parent entity, adjusted for the effects of all dilutive potential ordinary shares. [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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