XML 178 R155.htm IDEA: XBRL DOCUMENT v3.21.1

Related Party Transactions - Summary of Names of Related Parties and Relationship (Detail)	12 Months Ended
	Dec. 31, 2020
Unimos Shanghai [member]
Disclosure of transactions between related parties [Line Items]
Relationship	Associate
JMC ELECTRONICS CO., LTD. [member]
Disclosure of transactions between related parties [Line Items]
Relationship	Associate

X

- Definition

The description of the nature of the related party relationships. [Refer: Related parties [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 24
-IssueDate 2020-01-01
-Paragraph 18
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=24&code=ifrs-tx-2020-en-r&anchor=para_18&doctype=Standard
-URIDate 2020-01-01

+ Details

Name:	ifrs-full_DescriptionOfNatureOfRelatedPartyRelationship
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
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

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

X

- Details

Name:	ifrs-full_SignificantInvestmentsInAssociatesAxis=imos_UnimosShanghaiMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_SignificantInvestmentsInAssociatesAxis=imos_JMCELECTRONICSCOLTDMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: