XML 178 R164.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Income Tax - Major Components of Income Tax Expense (Detail) $ in Millions, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 TWD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 TWD ($) | Dec. 31, 2015 TWD ($)
Current tax |  |  |  |
Current tax expenses recognized for the year | $ 7,996 |  | $ 6,736 | $ 8,570
Tax on unappropriated earnings | (60) |  | (346) | 821
Income tax adjustments on prior years | (2) |  | (22) | (83)
Others | 10 |  | 15 | 15
Current tax | 7,944 |  | 6,383 | 9,323
Deferred tax |  |  |  |
Deferred tax expense recognized for the year | (101) |  | 1,404 | (222)
Income tax adjustments on prior years | 6 |  | 0 | 0
Deferred tax | (95) |  | 1,404 | (222)
Income tax expense recognized in profit or loss | $ 7,849 | $ 265 | $ 7,787 | $ 9,101

X
- Definition Other current tax expense (income). + References No definition available. + Details
Name: | cht_OtherCurrentTaxExpenseIncome
Namespace Prefix: | cht_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Tax effect of unappropriated earnings. + References No definition available. + Details
Name: | cht_TaxEffectOfUnappropriatedEarnings
Namespace Prefix: | cht_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Adjustments of tax expense (income) recognised in the period for current tax of prior periods. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 12 -IssueDate 2016-01-13 -Paragraph 80 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2016-03-30&anchor=para_80_b&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_AdjustmentsForCurrentTaxOfPriorPeriod
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Adjustments of tax expense (income) recognised in the period for the deferred tax of prior periods. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 12 -IssueDate 2016-01-13 -Paragraph 80 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2016-03-30&anchor=para_80&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_AdjustmentsForDeferredTaxOfPriorPeriods
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of income taxes payable (recoverable) in respect of the taxable profit (tax loss) for a period. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 12 -IssueDate 2016-01-13 -Paragraph 80 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2016-03-30&anchor=para_80_a&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_CurrentTaxExpenseIncome
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of current tax expense (income) and adjustments for the current tax of prior periods. [Refer: Current tax expense (income); Adjustments for current tax of prior periods] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 12 -IssueDate 2016-01-13 -Paragraph 80 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2016-03-30&anchor=para_80&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_CurrentTaxExpenseIncomeAndAdjustmentsForCurrentTaxOfPriorPeriods
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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

X
- Definition The amount of tax expense (income) relating to changes in deferred tax liabilities and deferred tax assets. [Refer: Deferred tax assets; Deferred tax liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2016-01-13 -Paragraph 81 -Subparagraph g -Clause ii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2016-03-30&anchor=para_81_g_ii&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_DeferredTaxExpenseIncome
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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

X
- Definition The amount of tax expense or income relating to changes in deferred tax liabilities and deferred tax assets, recognised in profit or loss. [Refer: Deferred tax assets; Deferred tax expense (income); Deferred tax liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2016-01-13 -Paragraph 81 -Subparagraph g -Clause ii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2016-03-30&anchor=para_81_g_ii&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_DeferredTaxExpenseIncomeRecognisedInProfitOrLoss
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition The aggregate amount included in the determination of profit (loss) for the period in respect of current tax and deferred tax that relate to continuing operations. [Refer: Continuing operations [member]; Current tax expense (income); Deferred tax expense (income)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2016-01-13 -Paragraph 23 -Subparagraph h -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=8&date=2016-03-30&anchor=para_23_h&doctype=Standard -URIDate 2016-03-31 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 26 -IssueDate 2016-01-13 -Paragraph 35 -Subparagraph b -Clause viii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=26&date=2016-03-30&anchor=para_35_b_viii&doctype=Standard -URIDate 2016-03-31 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2016-01-13 -Paragraph 79 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2016-03-30&anchor=para_79&doctype=Standard -URIDate 2016-03-31 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2016-01-13 -Paragraph 81 -Subparagraph c -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2016-03-30&anchor=para_81_c_i&doctype=Standard -URIDate 2016-03-31 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2016-01-13 -Paragraph 82 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2016-03-30&anchor=para_82_d&doctype=Standard -URIDate 2016-03-31 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2016-01-13 -Paragraph 81 -Subparagraph c -Clause ii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2016-03-30&anchor=para_81_c_ii&doctype=Standard -URIDate 2016-03-31 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2016-01-13 -Paragraph B13 -Subparagraph g -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=12&date=2016-03-30&anchor=para_B13_g&doctype=Appendix&seq=2 -URIDate 2016-03-31 + Details
Name: | ifrs-full_IncomeTaxExpenseContinuingOperations
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration