XML 142 R126.htm IDEA: XBRL DOCUMENT v3.8.0.1

Retirement Benefit Plans - Additional Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017 TWD ($) yr	Dec. 31, 2017 USD ($) yr	Dec. 31, 2016 TWD ($) yr	Dec. 31, 2015 TWD ($)	Dec. 31, 2017 USD ($)
Disclosure of defined benefit plans [line items]
Percentage of monthly pension contributions	6.00%	6.00%
Pension costs	$ 266,267	$ 8,983	$ 394,741	$ 413,490
Expected contribution to defined benefit plans	$ 521,324	$ 9,208	$ 272,911
Bottom of range [member]
Disclosure of defined benefit plans [line items]
Average duration of the defined benefit obligation	8	8	8
Top of range [member]
Disclosure of defined benefit plans [line items]
Average duration of the defined benefit obligation	14	14	15
Pension plans for executive managers [member]
Disclosure of defined benefit plans [line items]
Pension costs	$ 3,171	$ 107	$ 6,872	2,302
Pension payments	0	$ 0	0	$ 2,549
Accrued pension liabilities	$ 209,637		$ 206,467		$ 7,073

X

- Definition

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

+ References

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.

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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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X

- Definition

The decrease (increase) in the net defined benefit liability (asset) resulting from payments from the plan. [Refer: Net defined benefit liability (asset)]

+ References

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

- 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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- 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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- Definition

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

+ References

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