XML 132 R113.htm IDEA: XBRL DOCUMENT v3.21.1

Lease Arrangements - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2020
Land [member] | Bottom of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Lease Term	1 year
Land [member] | Top of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Lease Term	54 years
Buildings [member] | Bottom of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Lease Term	1 year
Buildings [member] | Top of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Lease Term	30 years

X

- Definition

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_
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Period Type:	duration

X

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

X

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

X

- Details

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

X

- Details

Name:	ifrs-full_ClassesOfPropertyPlantAndEquipmentAxis=ifrs-full_BuildingsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: