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Financial Assets at Fair Value through Other Comprehensive Income Noncurrent - Summary of Financial Assets at Fair Value through Other Comprehensive Income Noncurrent (Detail) $ in Millions, $ in Millions | Dec. 31, 2020 TWD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 TWD ($)
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Disclosure of financial assets [Line Items] |  |  |
Financial assets at fair value through other comprehensive income | $ 7,193 | $ 256 | $ 7,154
Domestic listed stocks [Member] |  |  |
Disclosure of financial assets [Line Items] |  |  |
Financial assets at fair value through other comprehensive income | 2,754 |  | 2,454
Domestic non-listed stocks [Member] |  |  |
Disclosure of financial assets [Line Items] |  |  |
Financial assets at fair value through other comprehensive income | 4,325 |  | 4,566
Foreign non-listed stocks [Member] |  |  |
Disclosure of financial assets [Line Items] |  |  |
Financial assets at fair value through other comprehensive income | $ 114 |  | $ 134

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- Definition Noncurrent financial assets at fair value through other comprehensive income. + References No definition available. + Details
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- Definition The amount of non-current financial assets at fair value through other comprehensive income. [Refer: Financial assets at fair value through other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 8 -Subparagraph h -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_8_h&doctype=Standard -URIDate 2020-01-01 + Details
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