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Contents of Significant Accounts - Major Components of Income Tax Expense (Detail) $ in Thousands, $ in Thousands | 12 Months Ended
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Dec. 31, 2024 TWD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 TWD ($) | Dec. 31, 2022 TWD ($)
Current income tax expense (benefit): |  |  |  |
Current income tax charge | $ 6,105,080 |  | $ 6,426,598 | $ 17,582,039
Adjustments in respect of current income tax of prior periods | (124,430) |  | (217,891) | (585,941)
Deferred income tax expense (benefit): |  |  |  |
Deferred income tax related to origination and reversal of temporary differences | 2,441,278 |  | 2,239,309 | 2,276,015
Deferred income tax related to recognition and derecognition of tax losses and unused tax credits | (34,010) |  | 0 | 60,178
Deferred income tax related to changes in tax rates | 68 |  | 0 | 0
Adjustment of prior year's deferred income tax | (3,227) |  | (120,230) | 8,611
Deferred income tax arising from write-down or reversal of write-down of deferred tax assets | (14,565) |  | (16,516) | (14,007)
Income tax expense recorded in profit or loss | 8,370,194 | $ 255,267 | 8,311,270 | 19,326,895
Income tax related to components of other comprehensive income (loss), Items that will not be reclassified subsequently to profit or loss |  |  |  |
Remeasurements of defined benefit pension plans | (37,690) |  | (80,447) | (59,361)
Unrealized gains or losses from equity instruments investments measured at fair value through other comprehensive income | 25,123 |  | (243,057) | (71,121)
Share of other comprehensive income (loss) of associates and joint ventures which will not be reclassified subsequently to profit or loss | 28,783 |  | (90,891) | 123,483
Income tax related to items that will not be reclassified subsequently to profit or loss | 16,216 | 495 | (414,395) | (6,999)
Income tax related to components of other comprehensive income (loss), Items that may be reclassified subsequently to profit or loss |  |  |  |
Exchange differences on translation of foreign operations | 153,317 |  | 386,660 | 883,238
Share of other comprehensive income (loss) of associates and joint ventures which may be reclassified subsequently to profit or loss | (24,317) |  | 3,768 | (23,672)
Income tax related to items that may be reclassified subsequently to profit or loss | 129,000 | $ 3,934 | 390,428 | 859,566
Income tax charged directly to equity |  |  |  |
Adjustments of changes in net assets of associates and joint ventures accounted for using equity method | $ 1,174 |  | $ (1,117) | $ (2,720)

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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 Deferred tax expense (income) relating to recognition and derecognition of tax losses and unused tax credits. + References No definition available. + Details
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