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Financial Risk and Fair Value Disclosures - Additional Information (Detail) - TWD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Accounts receivables from the top ten customers | 67.00% | 56.00% |
Profit or loss attributable to change in unrealized gains or losses for financial assets without quoted market prices held at end of period | $ (1,329) | $ (74) | $ 330
Profit or loss attributable to change in unrealized gains or losses for financial liabilities without quoted market prices held at end of period | (581) | 829 | (360)
Interest rate risk [member] |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Increase (decrease) in profit due to percentage increase in market risk | 36 | 19 | 39
Increase (decrease) in profit due to percentage decrease in market risk | $ (36) | $ (19) | $ (39)
Equity price risk [member] |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Percentage increase in market risk | 5.00% | 5.00% | 5.00%
Increase (decrease) in profit due to percentage increase in market risk | $ 270 | $ 285 | $ 393
Percentage decrease in market risk | 5.00% | 5.00% | 5.00%
Increase (decrease) in profit due to percentage decrease in market risk | $ (270) | $ (285) | $ (393)
Increase (decrease) in other comprehensive income due to percentage increase in market risk | 722 | 579 | 867
Increase (decrease) in other comprehensive income due to percentage decrease in market risk | $ (722) | $ (579) | $ (867)
Taiwan, New Dollars [member] | Currency risk [member] |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Percentage increase in market risk | 10.00% | 10.00% | 10.00%
Increase (decrease) in profit due to percentage increase in market risk | $ 620 | $ 1,305 | $ 1,104
Percentage decrease in market risk | 10.00% | 10.00% | 10.00%
Increase (decrease) in profit due to percentage decrease in market risk | $ (620) | $ (1,305) | $ (1,104)
China, Yuan Renminbi [member] | Currency risk [member] |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Percentage increase in market risk | 10.00% | 10.00% | 10.00%
Increase (decrease) in profit due to percentage increase in market risk | $ 582 | $ 572 | $ 375
Percentage decrease in market risk | 10.00% | 10.00% | 10.00%
Increase (decrease) in profit due to percentage decrease in market risk | $ (582) | $ (572) | $ (375)
Japan, Yen [member] | Currency risk [member] |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Percentage increase in market risk | 10.00% | 10.00% | 10.00%
Increase (decrease) in profit due to percentage increase in market risk | $ 290 | $ 538 | $ 434
Percentage decrease in market risk | 10.00% | 10.00% | 10.00%
Increase (decrease) in profit due to percentage decrease in market risk | $ (290) | $ (538) | $ (434)
Financial assets at fair value through profit or loss, category [member] |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Financial assets transfer from level two to level one | $ 655 |  |

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