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
-Name IAS
-Number 19
-IssueDate 2018-01-01
-Paragraph 147
-Subparagraph b
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-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Number 19
-IssueDate 2018-01-01
-Paragraph 148
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-URIDate 2018-03-16

+ Details

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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
-Name IAS
-Number 19
-IssueDate 2018-01-01
-Paragraph 5
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-URIDate 2018-03-16

+ Details

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Balance Type:	debit
Period Type:	duration

- 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
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_55&doctype=Standard
-URIDate 2018-03-16

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2018-01-01
-Paragraph 147
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-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_147_c&doctype=Standard
-URIDate 2018-03-16

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- Details

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Retirement Benefit Plans - Additional Information (Detail) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) yr	Dec. 31, 2018 TWD ($) yr	Dec. 31, 2017 TWD ($) yr	Dec. 31, 2016 TWD ($)	Dec. 31, 2018 TWD ($)
Disclosure of defined benefit plans [line items]
Percentage of monthly pension contributions	6.00%	6.00%	6.00%	6.00%
Pension costs	$ 9,518	$ 291,333	$ 266,267	$ 394,741
Expected contribution to defined benefit plans	15,820	484,247	272,911
Pension plans for executive managers [member]
Disclosure of defined benefit plans [line items]
Pension costs	364	$ 11,137	3,171	$ 6,872
Accrued pension liabilities	$ 10,472		$ 209,637		$ 320,542
Bottom of range [member]
Disclosure of defined benefit plans [line items]
Average duration of the defined benefit obligation	9	9	8
Top of range [member]
Disclosure of defined benefit plans [line items]
Average duration of the defined benefit obligation	15	15	14