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Share-based Payments Arrangement - Black-Scholes Model and Related Assumptions used to Evaluate Options and Fair Value of Options by SENAO (Detail) - Senao International Co., Ltd. (SENAO) [Member]	Nov. 17, 2017 TWD ($) d $ / shares	May 23, 2017 TWD ($) d $ / shares	May 07, 2013 TWD ($) yr $ / shares
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Grant-date share price | $ / shares	$ 51.00	$ 53.60	$ 93.00
Exercise price	$ 49.28	$ 49.28	$ 93.00
Dividends yield	0.00%	0.00%	0.00%
Risk-free interest rate	0.59%	0.59%	0.91%
Expected life	14	9	4.375
Expected volatility	9.94%	12.35%	36.22%
Weighted-average fair value of grants	$ 1.75	$ 4.33	$ 28.72

X

- Definition

Share price per share.

+ References

No definition available.

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- Definition

The expected volatility of the share price used to calculate the fair value of the share options granted. Expected volatility is a measure of the amount by which a price is expected to fluctuate during a period. The measure of volatility used in option pricing models is the annualised standard deviation of the continuously compounded rates of return on the share over a period of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-IssueDate 2016-01-13
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- Definition

The option life of share options granted.

+ References

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The implied yield currently available on zero-coupon government issues of the country in whose currency the exercise price for share options granted is expressed, with a remaining term equal to the expected term of the option being valued (based on the option's remaining contractual life and taking into account the effects of expected early exercise). [Refer: Government [member]]

+ References

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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.

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- Definition

The exercise price of share options granted.

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- Definition

The percentage of an expected dividend used to calculate the fair value of share options granted.

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The weighted average fair value of share options granted during the period at the measurement date. [Refer: Weighted average [member]]

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