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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, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Deferred tax assets and liabilities [abstract] |  |  |
Gain (loss) on valuation of financial assets at fair value through other comprehensive income, Before recognition | ₩ 163,750 | ₩ (216,862) | ₩ 163,892
Gain (loss) on valuation of hedge instruments (loss) liabilities, Before recognition | (30,168) | (42,510) | 6,916
Remeasurements of net defined benefit liabilities, Before recognition | (179,129) | 247,162 | 74,518
Share of Gain (loss) of associates and joint ventures, and others, Before recognition | 28,715 | (14,931) | (34,909)
Exchange differences on translation for foreign operations, Before recognition | 32,376 | 23,316 | 683
Gain or loss on disposal of treasury stock, Before recognition | 402 | (59,308) | (15,657)
Total, Before recognition | 15,946 | (63,133) | 195,443
Gain (loss) on valuation of financial assets at fair value through other comprehensive income, Tax effect | (41,945) | 58,288 | (34,112)
Gain (loss) on valuation of hedge instruments (loss) liabilities, Tax effect | 7,555 | 11,180 | (1,644)
Remeasurements of net defined benefit liabilities, Tax effect | 41,664 | (65,733) | (18,696)
Share of Gain (loss) of associates and joint ventures, and others, Tax effect | (7,225) | 3,748 | 9,097
Exchange differences on translation for foreign operations, Tax effect | (8,146) | (5,852) | (178)
Gain or loss on disposal of treasury stock, Tax effect | (101) | 14,886 | 4,080
Total, Tax effect | (8,198) | 16,517 | (41,453)
Gain (loss) on valuation of financial assets at fair value through other comprehensive income, After recognition | 121,805 | (158,574) | 129,780
Gain (loss) on valuation of hedge instruments (loss) liabilities, After recognition | (22,613) | (31,330) | 5,272
Remeasurements of net defined benefit liabilities, After recognition | (137,465) | 181,429 | 55,822
Share of Gain (loss) of associates and joint ventures, and others, After recognition | 21,490 | (11,183) | (25,812)
Exchange differences on translation for foreign operations, After recognition | 24,230 | 17,464 | 505
Gain or loss on disposal of treasury stock, After recognition | 301 | (44,422) | (11,577)
Total other comprehensive income | ₩ 7,748 | ₩ (46,616) | ₩ 153,990

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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 2023-01-01 -Paragraph 91 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_91_b&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2023-01-01 -Paragraph 20 -Subparagraph a -Clause viii -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_20_a_viii&doctype=Standard -URIDate 2023-03-23 + 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, net of 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 2023-01-01 -Paragraph 91 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_91_a&doctype=Standard -URIDate 2023-03-23 + 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 12 -IssueDate 2023-01-01 -Paragraph 81 -Subparagraph ab -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2023-en-r&anchor=para_81_ab&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 90 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_90&doctype=Standard -URIDate 2023-03-23 + 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 12 -IssueDate 2023-01-01 -Paragraph 81 -Subparagraph ab -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2023-en-r&anchor=para_81_ab&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 90 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_90&doctype=Standard -URIDate 2023-03-23 + 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 12 -IssueDate 2023-01-01 -Paragraph 81 -Subparagraph ab -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2023-en-r&anchor=para_81_ab&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 90 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_90&doctype=Standard -URIDate 2023-03-23 + 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 12 -IssueDate 2023-01-01 -Paragraph 81 -Subparagraph ab -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2023-en-r&anchor=para_81_ab&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 90 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_90&doctype=Standard -URIDate 2023-03-23 + 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 [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2023-01-01 -Paragraph 81 -Subparagraph ab -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2023-en-r&anchor=para_81_ab&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 90 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_90&doctype=Standard -URIDate 2023-03-23 + 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 2023-01-01 -Paragraph 91 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_91&doctype=Standard -URIDate 2023-03-23 + 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 2023-01-01 -Paragraph 91 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_91_b&doctype=Standard -URIDate 2023-03-23 + 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 2023-01-01 -Paragraph 91 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_91_b&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 7 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_7&doctype=Standard -URIDate 2023-03-23 + 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 [member]; 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/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2023-01-01 -Paragraph 135 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_135_b&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 91 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_91_b&doctype=Standard -URIDate 2023-03-23 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 7 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_7&doctype=Standard -URIDate 2023-03-23 + Details
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