Financial Risk Management and Fair Values of Financial Instruments - Summary of Investments Financial Assets At Amortized Cost (Detail) - TWD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Disclosure of fair value financial assets amortised cost [line items]
Financial assets at amortized cost Bank deposits	$ 237,420	$ 268,271
Twelve months [member]
Disclosure of fair value financial assets amortised cost [line items]
Financial assets at amortized cost Bank deposits	$ 237,420	$ 268,271

The amount of financial assets at amortised cost. The amortised cost is the amount at which financial assets are measured at initial recognition minus principal repayments, plus or minus the cumulative amortisation using the effective interest method of any difference between that initial amount and the maturity amount, and adjusted for any impairment. [Refer: Financial assets]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2019-01-01
-Paragraph 8
-Subparagraph f
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2019-en-r&anchor=para_8_f&doctype=Standard
-URIDate 2019-03-27

Name:	ifrs-full_FinancialAssetsAtAmortisedCost
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant