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Financial Instruments - Sensitivity Analysis of Financial Assets and Financial Liabilities Classified as Level 3 of Fair Value Hierarchy (Detail) - Available-for-sale financial assets [member] ₩ in Millions	12 Months Ended
	Dec. 31, 2025 KRW (₩)
Fluctuation 0.5% of growth rate [member]
Disclosure of significant unobservable inputs used in fair value measurement of assets [line items]
Favorable changes	₩ 336
Unfavorable changes	(302)
Fluctuation 0.5% of discount rate [member]
Disclosure of significant unobservable inputs used in fair value measurement of assets [line items]
Favorable changes	3,474
Unfavorable changes	₩ (3,682)

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- Definition

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.

+ References

No definition available.

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- Definition

The amount of increase (decrease) in the fair value measurement of assets due to a reasonably possible decrease in an unobservable input.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 13
-IssueDate 2025-01-01
-Paragraph 93
-Subparagraph h
-Clause ii
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- Definition

The amount of increase (decrease) in the fair value measurement of assets due to a reasonably possible increase in an unobservable input.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Number 13
-IssueDate 2025-01-01
-Paragraph 93
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-URIDate 2025-03-27

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