XML 192 R173.htm IDEA: XBRL DOCUMENT
v3.19.1

Income Tax - Summary of Unused Investment Credits (Detail) - 12 months ended Dec. 31, 2018 $ in Thousands, $ in Thousands | USD ($) | TWD ($)
--- | --- | ---
Unused tax credits [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Remaining Creditable Amount | $ 20,619 | $ 631,166
Purchase of machinery and equipment [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Expiry Year | 2022 |
Purchase of machinery and equipment [member] | Unused tax credits [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Remaining Creditable Amount | $ 19,297 | 590,694
Others [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Expiry Year | 2023 and thereafter |
Others [member] | Unused tax credits [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Remaining Creditable Amount | $ 1,322 | $ 40,472

X
- Definition Unused tax credits expiration description. + References No definition available. + Details
Name: | asx_UnusedTaxCreditsExpirationDescription
Namespace Prefix: | asx_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
Name: | ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of deferred tax liabilities net of deferred tax assets, when the absolute amount of deferred tax liabilities is greater than the absolute amount of deferred tax assets. [Refer: Deferred tax assets; Deferred tax liabilities] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 12 -IssueDate 2018-01-01 -Paragraph 81 -Subparagraph g -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2018-03-01&anchor=para_81_g_i&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_NetDeferredTaxLiabilities
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=ifrs-full_UnusedTaxCreditsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_AssetsAndLiabilitiesAxis=asx_PurchaseOfMachineryAndEquipmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_AssetsAndLiabilitiesAxis=asx_OtherTaxesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |