Net Defined Benefit Liabilities (Assets) - Schedule of Sensitivity of the Defined Benefit Obligations (Details) ₩ in Millions	Dec. 31, 2025 KRW (₩)
Discount rate
Disclosure of sensitivity analysis for actuarial assumptions [Line items]
Changes in assumption	0.50%
Increase in assumption	₩ (72,199)
Decrease in assumption	₩ 78,104
Salary growth rate
Disclosure of sensitivity analysis for actuarial assumptions [Line items]
Changes in assumption	0.50%
Increase in assumption	₩ 75,203
Decrease in assumption	₩ (70,258)

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-IssueDate 2025-01-01
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-URIDate 2025-03-27

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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

Percentage of reasonably possible increase decrease in actuarial assumption.

+ References

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