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Deferred Income Tax and Income Tax Expense - Summary of Tax Impacts Recognized Directly To Equity (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Deferred tax assets and liabilities [abstract] |  |  |
Gain (loss) on valuation of financial assets at fair value through other comprehensive income, Before recognition | ₩ 7,626 | ₩ 163,750 | ₩ (216,862)
Gain (loss) on valuation of hedge instruments (loss) liabilities, Before recognition | (17,707) | (30,168) | (42,510)
Remeasurements of net defined benefit liabilities, Before recognition | (159,757) | (179,129) | 247,162
Share of Gain (loss) of associates and joint ventures, and others, Before recognition | 4,715 | 28,715 | (14,931)
Exchange differences on translation for foreign operations, Before recognition | 59,053 | 32,376 | 23,316
Gain or loss on disposal of treasury stock, Before recognition | (76) | 402 | (59,308)
Total, Before recognition | (106,146) | 15,946 | (63,133)
Gain (loss) on valuation of financial assets at fair value through other comprehensive income, Tax effect | (1,932) | (41,945) | 58,288
Gain (loss) on valuation of hedge instruments (loss) liabilities, Tax effect | 4,555 | 7,555 | 11,180
Remeasurements of net defined benefit liabilities, Tax effect | 42,700 | 41,664 | (65,733)
Share of Gain (loss) of associates and joint ventures, and others, Tax effect | (1,194) | (7,225) | 3,748
Exchange differences on translation for foreign operations, Tax effect | (14,958) | (8,146) | (5,852)
Gain or loss on disposal of treasury stock, Tax effect | 19 | (101) | 14,886
Total, Tax effect | 29,190 | (8,198) | 16,517
Gain (loss) on valuation of financial assets at fair value through other comprehensive income, After recognition | 5,694 | 121,805 | (158,574)
Gain (loss) on valuation of hedge instruments (loss) liabilities, After recognition | (13,152) | (22,613) | (31,330)
Remeasurements of net defined benefit liabilities, After recognition | (117,057) | (137,465) | 181,429
Share of Gain (loss) of associates and joint ventures, and others, After recognition | 3,521 | 21,490 | (11,183)
Exchange differences on translation for foreign operations, After recognition | 44,095 | 24,230 | 17,464
Gain or loss on disposal of treasury stock, After recognition | (57) | 301 | (44,422)
Total other comprehensive income | ₩ (76,956) | ₩ 7,748 | ₩ (46,616)

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- Definition The gains (losses) on financial assets at fair value through profit or loss that were designated as such upon initial recognition or subsequently. [Refer: Financial assets at fair value through profit or loss, designated upon initial recognition or subsequently; Gains (losses) on financial assets at fair value through profit or loss] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph 20 -Subparagraph a -Clause i -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_20_a_i&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The gains (losses) recognised in other comprehensive income on financial assets measured at fair value through other comprehensive income applying paragraph 4.1.2A of IFRS 9, before tax, before reclassification adjustments. [Refer: Financial assets measured at fair value through other comprehensive income; Other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 91 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_91_b&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph 20 -Subparagraph a -Clause viii -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_20_a_viii&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of income tax relating to amounts recognised in other comprehensive income in relation to cash flow hedges. [Refer: Cash flow hedges [member]; Other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 90 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_90&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2024-01-01 -Paragraph 81 -Subparagraph ab -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2024-en-r&anchor=para_81_ab&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of income tax relating to amounts recognised in other comprehensive income. [Refer: Other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 90 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_90&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2024-01-01 -Paragraph 81 -Subparagraph ab -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2024-en-r&anchor=para_81_ab&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of income tax relating to amounts recognised in other comprehensive income in relation to exchange differences on the translation of financial statements of foreign operations. [Refer: Other comprehensive income; Reserve of exchange differences on translation] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 90 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_90&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2024-01-01 -Paragraph 81 -Subparagraph ab -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2024-en-r&anchor=para_81_ab&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of income tax relating to amounts recognised in other comprehensive income in relation to financial assets measured at fair value through other comprehensive income applying paragraph 4.1.2A of IFRS 9. [Refer: Financial assets measured at fair value through other comprehensive income; Other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 90 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_90&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2024-01-01 -Paragraph 81 -Subparagraph ab -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2024-en-r&anchor=para_81_ab&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of income tax relating to amounts recognised in other comprehensive income in relation to remeasurements of defined benefit plans. [Refer: Other comprehensive income; Reserve of remeasurements of defined benefit plans; Defined benefit plans [domain]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 90 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_90&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2024-01-01 -Paragraph 81 -Subparagraph ab -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2024-en-r&anchor=para_81_ab&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of income tax relating to an entity's share of other comprehensive income of associates and joint ventures accounted for using the equity method that will be reclassified to profit or loss. [Refer: Share of other comprehensive income of associates and joint ventures accounted for using equity method, before tax] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 91 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_91&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of other comprehensive income, before tax. [Refer: Other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 91 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_91_b&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of other comprehensive income, before tax, after reclassification adjustments, related to exchange differences on translation of financial statements of foreign operations. [Refer: Other comprehensive income, before tax] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 91 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_91_b&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 7 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_7&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of other comprehensive income, before tax, related to gains (losses) on remeasurements of defined benefit plans, which comprise actuarial gains and losses; the return on plan assets, excluding amounts included in net interest on the net defined benefit liability (asset); and any change in the effect of the asset ceiling, excluding amounts included in net interest on the net defined benefit liability (asset). [Refer: Other comprehensive income; Defined benefit plans [domain]; Plan assets [member]; Net defined benefit liability (asset)] [Contrast: Decrease (increase) in net defined benefit liability (asset) resulting from gain (loss) on remeasurement in other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 91 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_91_b&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 7 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_7&doctype=Standard -URIDate 2024-03-27 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2024-01-01 -Paragraph 135 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_135_b&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of other comprehensive income, net of tax, after reclassification adjustments, related to cash flow hedges. [Refer: Cash flow hedges [member]; Other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 91 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_91_a&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 7 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_7&doctype=Standard -URIDate 2024-03-27 + Details
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