The amount received or receivable from the issuance of the entity's shares in excess of nominal value and amounts received from other transactions involving the entity's stock or stockholders.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
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-IssueDate 2019-01-01
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-URIDate 2019-03-27

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The amount of treasury stock cancelled during the period. [Refer: Treasury shares]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 106
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_106_d&doctype=Standard
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The decrease in equity resulting from a reduction in issued capital. [Refer: Issued capital]

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Cash distribution from capital surplus.

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No definition available.

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Increase (decrease) through issuance of restricted shares, equity.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Capital Surplus and Retained Earnings - Details of Capital Surplus (Detail) $ in Thousands, $ in Thousands	5 Months Ended	12 Months Ended
	Aug. 06, 2019 TWD ($)	Dec. 31, 2019 TWD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 TWD ($)	Dec. 31, 2017 TWD ($)
Statement [LineItems]
Beginning balance		$ 6,263,553
Share-based payments		822		$ 41,043	$ 123,021
Cash distribution from capital surplus					(599,728)
Capital reduction				(1,284,223)	0
Cancellation of treasury stock	$ 962,503
Ending balance		6,050,787	$ 202,300	6,263,553
Capital surplus [member]
Statement [LineItems]
Beginning balance		6,263,553		6,271,448	6,888,826
Share-based payments		(412)		(7,967)	(17,650)
Cash distribution from capital surplus					(599,728)
Capital reduction				72
Cancellation of treasury stock		(212,354)
Ending balance		6,050,787		6,263,553	6,271,448
Share premium [member] \| Capital surplus [member]
Statement [LineItems]
Beginning balance		5,873,743		5,873,743	6,473,471
Cash distribution from capital surplus					(599,728)
Cancellation of treasury stock		(199,501)
Ending balance		5,674,242		5,873,743	5,873,743
Employee restricted shares [member] \| Capital surplus [member]
Statement [LineItems]
Beginning balance		382,506		390,401	408,051
Share-based payments		(412)		(7,967)	(17,650)
Capital reduction				72
Cancellation of treasury stock		(12,853)
Ending balance		369,241		382,506	390,401
Others [member] \| Capital surplus [member]
Statement [LineItems]
Beginning balance		7,304		7,304	7,304
Ending balance		$ 7,304		$ 7,304	$ 7,304