XML 173 R159.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Net Income and Other Comprehensive Income (Loss) - Impairment Loss (Reversal of Impairment Loss) on Financial Instruments and Non-financial Assets (Detail) $ in Millions, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 TWD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 TWD ($) | Dec. 31, 2015 TWD ($)
Disclosure Of Impairment Loss And Reversal Of Impairment Loss [Abstract] |  |  |  |
Trade notes and accounts receivable | $ 578 |  | $ 943 | $ 480
Other receivables | 65 |  | (2) | 39
Available-for-sale financial assets | 0 | $ 0 | 577 | 107
Inventories | 52 | 2 | 192 | 198
Impairment losses | 0 | 0 | 596 | 138
Impairment loss on investments accounted for using equity method | 0 | 0 | 0 | 8
Investment properties | (11) | 0 | (148) | (142)
Impairment loss on intangible assets | $ 9 | $ 0 | $ 0 | $ 0

X
- Definition Impairment loss on investments accounted for using equity method. + References No definition available. + Details
Name: | cht_ImpairmentLossOnInvestmentsAccountedForUsingEquityMethod
Namespace Prefix: | cht_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Impairment loss (reversal of impairment loss) recognised in profit or loss available-for-sale financial assets. + References No definition available. + Details
Name: | cht_ImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossAvailableforsaleFinancialAssets
Namespace Prefix: | cht_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Impairment loss (reversal of impairment loss) recognised in profit or loss other receivables. + References No definition available. + Details
Name: | cht_ImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossOtherReceivables
Namespace Prefix: | cht_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | ifrs-full_DisclosureOfImpairmentLossAndReversalOfImpairmentLossAbstract
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of impairment loss recognised in profit or loss for intangible assets and goodwill. [Refer: Impairment loss recognised in profit or loss; Intangible assets and goodwill] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 38 -IssueDate 2016-01-13 -Paragraph 118 -Subparagraph e -Clause iv -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=38&date=2016-03-30&anchor=para_118_e_iv&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_ImpairmentLossRecognisedInProfitOrLossIntangibleAssetsAndGoodwill
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of impairment loss recognised in profit or loss for property, plant and equipment. [Refer: Impairment loss recognised in profit or loss; Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2016-01-13 -Paragraph 73 -Subparagraph e -Clause v -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=16&date=2016-03-30&anchor=para_73_e_v&doctype=Standard -URIDate 2016-03-31 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2016-01-13 -Paragraph 98 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2016-03-30&anchor=para_98_a&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_ImpairmentLossRecognisedInProfitOrLossPropertyPlantAndEquipment
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of impairment loss or reversal of impairment loss recognised in profit or loss for trade receivables. [Refer: Impairment loss recognised in profit or loss; Reversal of impairment loss recognised in profit or loss; Trade receivables] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2016-01-13 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2016-03-30&anchor=para_112_c&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_ImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossTradeReceivables
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of expense recognised related to the write-down of inventories to net realisable value. [Refer: Inventories] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 2 -IssueDate 2016-01-13 -Paragraph 36 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=2&date=2016-03-30&anchor=para_36_e&doctype=Standard -URIDate 2016-03-31 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2016-01-13 -Paragraph 98 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2016-03-30&anchor=para_98_a&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_InventoryWritedown2011
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of reversal of impairment loss recognised in profit or loss for investment property. [Refer: Reversal of impairment loss recognised in profit or loss; Investment property] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 40 -IssueDate 2016-01-13 -Paragraph 76 -Subparagraph g -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2016-03-30&anchor=para_76_g&doctype=Standard -URIDate 2016-03-31 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 40 -IssueDate 2016-01-13 -Paragraph 79 -Subparagraph d -Clause v -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2016-03-30&anchor=para_79_d_v&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_ReversalOfImpairmentLossRecognisedInProfitOrLossInvestmentProperty
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration