XML 232 R121.htm IDEA: XBRL DOCUMENT v3.20.1

Investment Properties - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2019
Bottom of range [member]
Disclosure of detailed information about investment property [line items]
Operating lease Term	1 year
Top of range [member]
Disclosure of detailed information about investment property [line items]
Operating lease Term	15 years

X

- Definition

Operating lease Term

+ References

No definition available.

+ Details

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Namespace Prefix:	asx_
Data Type:	xbrli:durationItemType
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

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

X

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_RangeAxis=ifrs-full_TopOfRangeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: