Retirement Benefit Plans - Summary of Fair Value of the Plan Assets by Major Categories (Detail) $ in Thousands, $ in Thousands |
Dec. 31, 2025
TWD ($)
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Dec. 31, 2025
USD ($)
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Dec. 31, 2024
TWD ($)
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| Disclosure of fair value of plan assets [abstract] | |||
| Cash | $ 2,409,488 | $ 76,809 | $ 2,394,070 |
| Equity instruments | 3,810,844 | 121,480 | 3,305,989 |
| Debt instruments | 1,370,940 | 43,702 | 1,246,361 |
| Others | 227,873 | 7,264 | 307,890 |
| Total | $ 7,819,145 | $ 249,255 | $ 7,254,310 |
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- Definition The amount cash and cash equivalents contribute to the fair value of defined benefit plan assets. [Refer: Cash and cash equivalents; Plan assets, at fair value; Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition The amount instruments representing debt (rather than equity) contribute to the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- References No definition available.
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- Definition The amount instruments representing equity (rather than debt) contribute to the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition The amount other types of assets not separately disclosed contribute to the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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