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Employee Benefits - Changes to Defined Benefit Obligation Due to Reasonably Possible Changes to one of the Relevant Actuarial Assumptions (Detail) ₩ in Millions	Dec. 31, 2025 KRW (₩)
Discount rate [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Affect on defined benefit obligation due to reasonably possible 1% increase in actuarial assumption	₩ (164,782)
Affect on defined benefit obligation due to reasonably possible 1% decrease in actuarial assumption	₩ 190,289
Percentage of reasonably possible 1% decrease in actuarial assumption	7.20%
Percentage of reasonably possible 1% increase decrease in actuarial assumption	(6.30%)
Expected future increase in salaries [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Affect on defined benefit obligation due to reasonably possible 1% increase in actuarial assumption	₩ 186,448
Affect on defined benefit obligation due to reasonably possible 1% decrease in actuarial assumption	₩ (165,385)
Percentage of reasonably possible 1% increase in actuarial assumption	7.10%
Percentage of reasonably possible 1% increase decrease in actuarial assumption	(6.30%)

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- Definition

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+ References

No definition available.

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- Definition

The increase (decrease) in a defined benefit obligation that would have been caused by a decrease in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [domain]]

+ References

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- Definition

The increase (decrease) in a defined benefit obligation that would have been caused by an increase in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [domain]]

+ References

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- Definition

The reasonably possible percentage of the decrease in the actuarial assumption used to determine the present value of defined benefit obligation. [Refer: Actuarial assumptions [domain]]

+ References

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- Definition

The reasonably possible percentage of the increase in the actuarial assumption used to determine the present value of defined benefit obligation. [Refer: Actuarial assumptions [domain]]

+ References

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Percentage of reasonably possible increase decrease in actuarial assumption.

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