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Equity - Unrealized Gain or Loss on Financial Assets at FVOCI (Detail) - TWD ($) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Jan. 01, 2019 | Jan. 01, 2018
Beginning balance | $ 538 | $ 0 |  |
Effect of retrospective application of IFRS 9 |  |  | $ 0 | $ 883
Unrealized gain (loss) for the year |  |  |  |
Equity instruments | 197 | (345) |  |
Ending balance | 735 | 538 |  |
IFRS 9 [Member] |  |  |  |
Beginning balance | $ 538 | 883 |  |
Unrealized gain (loss) for the year |  |  |  |
Ending balance |  | $ 538 |  |

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- Definition Unrealized gain or loss for the year. + References No definition available. + Details
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- Definition Unrealized gain (loss) on equity instrument. + References No definition available. + Details
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- Definition Unrealized gain or loss on financial assets at fair value through other comprehensive income. + References No definition available. + Details
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- Definition The increase (decrease) in financial assets arising from a change in measurement attribute on the entity's transition to IFRS 9. [Refer: Financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2019-01-01 -Paragraph 42L -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2019-en-r&anchor=para_42L_b&doctype=Standard -URIDate 2019-03-27 + Details
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- Details
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