Contents of Significant Accounts - Financial Liabilities at Fair Value through Profit or Loss, Current (Detail) - Dec. 31, 2020 $ in Thousands, $ in Thousands	TWD ($)	USD ($)
Current Financial Assets At Fair Value Through Profit Or Loss [Line Items]
Forward contracts	$ 2,326	$ 83
Forward exchange contracts [member]
Current Financial Assets At Fair Value Through Profit Or Loss [Line Items]
Forward contracts	$ 2,326

The amount of current financial liabilities measured at fair value through profit or loss. [Refer: Financial liabilities at fair value through profit or loss]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2020-01-01
-Paragraph 8
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_8_e&doctype=Standard
-URIDate 2020-01-01

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant