XML 151 R132.htm IDEA: XBRL DOCUMENT
v3.19.1

Borrowings - Summary of Long-term Bills Payable (Detail) $ in Thousands, $ in Thousands | Dec. 31, 2018 USD ($) | Dec. 31, 2018 TWD ($) | Dec. 31, 2017 TWD ($)
--- | --- | --- | ---
Disclosure of detailed information about borrowings [line items] |  |  |
Long-term bills payable | $ 101,249 | $ 3,099,232 | $ 1,999,132
Unamortized Discounts [member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Long-term bills payable | 25 | 768 | 868
Longterm Bills Payable [member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Long-term bills payable | 101,274 | 3,100,000 | 2,000,000
China Bills Finance Corporation [member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Long-term bills payable | 32,669 | 1,000,000 | 1,000,000
International Bills Finance Corporation [member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Long-term bills payable | 32,669 | 1,000,000 | $ 1,000,000
Ta Ching Bills Finance Corporation [member] |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |
Long-term bills payable | $ 35,936 | $ 1,100,000 |

X
- Definition Non-current portion of non-current bills issued. + References No definition available. + Details
Name: | asx_NoncurrentPortionOfNoncurrentBillsIssued
Namespace Prefix: | asx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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_DisclosureOfDetailedInformationAboutBorrowingsLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis=asx_UnamortizedDiscountsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_BorrowingsByNameAxis=asx_LongtermBillsPayableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CategoriesOfRelatedPartiesAxis=asx_ChinaBillsFinanceCorporationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CategoriesOfRelatedPartiesAxis=asx_InternationalBillsFinanceCorporationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CategoriesOfRelatedPartiesAxis=asx_TaChingBillsFinanceCorporationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |