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Equity - Unrealized Gain or Loss on Financial Assets at FVOCI (Detail) - TWD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017
Effect of retrospective application of IFRS 9 |  | $ 883
Unrealized gain or loss for the year |  |
Equity instruments | $ (345) |
Ending balance | 538 |
IFRS 9 [Member] |  |
Beginning balance | $ 883 |

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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 2018-01-01 -Paragraph 42L -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_42L_b&doctype=Standard -URIDate 2018-03-16 + Details
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- Details
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