Percentage of employees monthly wages and salaries as contributions to defined benefit plan

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The estimate of the expected contributions to be made to a defined benefit plan for the next annual reporting period. [Refer: Defined benefit plans [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of post-employment benefit expense relating to defined benefit plans. [Refer: Defined benefit plans [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details

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- Definition

The amount of deficit in a defined benefit plan. [Refer: Defined benefit plans [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details

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- Definition

The weighted average duration of a defined benefit obligation. [Refer: Weighted average [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Retirement Benefit Plans - Additional Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021 TWD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 TWD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 TWD ($)	Dec. 31, 2018 TWD ($)	Dec. 31, 2020 USD ($)
Disclosure of defined benefit plans [line items]
Percentage of monthly pension contributions			6.00%	6.00%	6.00%	6.00%
Pension costs			$ 217,186	$ 7,735	$ 277,041	$ 291,333
Expected contribution to defined benefit plans	$ 513,781	$ 18,297	533,777
Pension plans for executive managers [member]
Disclosure of defined benefit plans [line items]
Pension costs			11,184	$ 398	11,567	$ 11,137
Accrued pension liabilities			$ 346,015		$ 335,109		$ 12,322
Bottom of range [member]
Disclosure of defined benefit plans [line items]
Average duration of the defined benefit obligation			9 years	9 years	10 years
Top of range [member]
Disclosure of defined benefit plans [line items]
Average duration of the defined benefit obligation			16 years	16 years	14 years