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Percentage of trade receivables.

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

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The measure of a potential loss exposure as a result of future market movements, based on a specified confidence interval and measurement horizon.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 7
-IssueDate 2025-01-01
-Paragraph 41
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2025-en-r&anchor=para_41&doctype=Standard
-URIDate 2025-03-27

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Financial Instruments - Additional Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2025 TWD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 TWD ($)	Dec. 31, 2023 TWD ($)	Dec. 31, 2025 USD ($)
Disclosure of detailed information about financial instruments [line items]
Increase percentage of significant unobservable inputs discount rate	1.00%	1.00%	0.10%
Fair value of bonds decreased	$ 26,700	$ 851	$ 157,800
Percentage of trade receivables	50.00%		47.00%		50.00%
Bottom of range [member]
Disclosure of detailed information about financial instruments [line items]
Significant unobservable inputs discount rate	15.00%	15.00%
Bottom of range [member] \| Actuarial assumption of discount rates [member]
Disclosure of detailed information about financial instruments [line items]
Significant unobservable inputs discount rate	12.30%	12.30%
Top of range [member]
Disclosure of detailed information about financial instruments [line items]
Significant unobservable inputs discount rate	30.00%	30.00%
Top of range [member] \| Actuarial assumption of discount rates [member]
Disclosure of detailed information about financial instruments [line items]
Significant unobservable inputs discount rate	17.50%	17.50%
Floating interest rate [member]
Disclosure of detailed information about financial instruments [line items]
Increase decrease in profit before tax	$ 1,833,000	$ 58,432	$ 1,049,000	$ 660,000
Currency risk [member]
Disclosure of detailed information about financial instruments [line items]
Value at risk	149,000		274,000	148,000	$ 4,750
Other price risk [member]
Disclosure of detailed information about financial instruments [line items]
Increase decrease in profit before tax	$ 50,000	$ 1,594	$ 53,000	$ 46,500
Percentage change in equity price	1.00%	1.00%	1.00%	1.00%
Increase decrease in other comprehensive income	$ 126,000	$ 4,017	$ 129,000	$ 6,000