Employee benefit expenses - Summary of Employee benefit expenses (Detail) - TWD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Classes of employee benefits expense [abstract]
Salaries	$ 5,139,741	$ 4,741,380	$ 5,302,234
Directors' remuneration	22,718	23,980	28,621
Labor and health insurance	477,338	432,568	449,223
Pension	215,840	195,359	205,671
Other personnel expenses	594,897	442,781	480,554
Total Employee benefit expenses	$ 6,450,534	$ 5,836,068	$ 6,466,303

No definition available.

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- Definition

The amount of remuneration paid or payable to the entity's directors.

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The expense of all forms of consideration given by an entity in exchange for a service rendered by employees or for the termination of employment.

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The amount of employee expenses that the entity does not separately disclose in the same statement or note.

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- Definition

The amount of expense from employee benefits (other than termination benefits), which are expected to be settled wholly within twelve months after the end of the annual reporting period in which the employees render the related services, that the entity does not separately disclose in the same statement or note. [Refer: Employee benefits expense]

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The amount of post-employment benefit expense included in profit or loss relating to defined benefit plans. [Refer: Profit (loss); Defined benefit plans [domain]] [Contrast: Increase (decrease) in net defined benefit liability (asset) resulting from expense (income) in profit or loss]

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- Definition

A class of employee benefits expense that represents wages and salaries. [Refer: Employee benefits expense]

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