XML 112 R96.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Other Financial Assets - Additional Information (Detail) | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Disclosure of financial assets [abstract] |  |
Corporate bonds annual interest rate | 3.50% | 3.50%

X
- Definition Interest rate on unsecured subordinate corporate bonds. + References No definition available. + Details
Name: | asx_InterestRateOnUnsecuredSubordinateCorporateBonds
Namespace Prefix: | asx_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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