Income Tax Expense - Additional Information (Detail) - TWD ($) $ in Thousands		3 Months Ended
Oct. 31, 2016	Jun. 30, 2020	Dec. 31, 2021	Dec. 31, 2020
Disclosure of income tax expense [Line Items]
Taxable temporary differences not recognized as deferred tax liaibility			$ 609,709	$ 45,005
Reduction of unappropriated retained earnings through capital transfer	$ 5,052,343
Income taxes paid (refund)		$ 138,941

The aggregate amount of temporary differences associated with investments in subsidiaries, branches and associates and interests in joint arrangements, for which deferred tax liabilities have not been recognised as a result of satisfying both of the following conditions: (a) the parent, investor, joint venturer or joint operator is able to control the timing of the reversal of the temporary difference; and (b) it is probable that the temporary difference will not reverse in the foreseeable future. [Refer: Associates [member]; Subsidiaries [member]; Temporary differences [member]; Investments in subsidiaries reported in separate financial statements]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2021-01-01
-Paragraph 81
-Subparagraph f
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2021-en-r&anchor=para_81_f&doctype=Standard
-URIDate 2021-03-24

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant