XML 116 R100.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Investments Accounted for Using the Equity Method - Summary of Retrospective Adjustments (Detail) $ in Thousands, $ in Thousands | Dec. 31, 2017 TWD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 TWD ($)
--- | --- | --- | ---
Disclosure of associates and joint ventures [line items] |  |  |
Investments accounted for using the equity method | $ 48,267,237 | $ 1,628,449 | $ 49,154,140
Deca Technologies Inc. [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Investments accounted for using the equity method |  |  | 1,813,677
Deca Technologies Inc. [member] | Previously stated [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Investments accounted for using the equity method |  |  | 1,820,329
Advanced Microelectronic Products Inc. [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Investments accounted for using the equity method |  |  | 264,434
Advanced Microelectronic Products Inc. [member] | Previously stated [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Investments accounted for using the equity method |  |  | $ 266,085

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

X
- Definition The amount of investments in associates. [Refer: Associates [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 27 -IssueDate 2017-01-01 -Paragraph 10 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=27&date=2017-03-01&anchor=para_10&doctype=Standard -URIDate 2017-03-09 + Details
Name: | ifrs-full_InvestmentsInAssociates
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | ifrs-full_SignificantInvestmentsInAssociatesAxis=asx_DecaTechnologiesIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_RetrospectiveApplicationAndRetrospectiveRestatementAxis=ifrs-full_PreviouslyStatedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_SignificantInvestmentsInAssociatesAxis=asx_AdvancedMicroelectronicProductsIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |