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Share-based Payments Arrangement - Black-Scholes Model and Related Assumptions used to Evaluate Options and Fair Value of Options by CHPT (Detail) - Chunghwa Precision Test Tech. Co., Ltd. (CHPT) [Member] | Sep. 18, 2017 TWD ($) d $ / shares | Mar. 10, 2016 TWD ($) d $ / shares
--- | --- | ---
Disclosure of terms and conditions of share-based payment arrangement [Line Items] |  |
Grant-date share price | $ / shares | $ 1,295.00 | $ 302.46
Exercise price | $ 1,267.33 | $ 360.00
Dividends yield | 0.00% | 0.00%
Risk-free interest rate | 0.35% | 0.37%
Expected life | d | 4 | 12
Expected volatility | 28.30% | 37.43%
Weighted average fair value of grants | $ 31.60 | $ 0.04

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- Definition Share price per share. + References No definition available. + Details
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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 -Name IFRS -Number 2 -IssueDate 2016-01-13 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2016-03-30&anchor=para_47_a_i&doctype=Standard -URIDate 2016-03-31 + Details
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- Definition The option life of share options granted. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2016-01-13 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2016-03-30&anchor=para_47_a_i&doctype=Standard -URIDate 2016-03-31 + Details
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- Definition 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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2016-01-13 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2016-03-30&anchor=para_47_a_i&doctype=Standard -URIDate 2016-03-31 + Details
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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 exercise price of share options granted. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2016-01-13 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2016-03-30&anchor=para_47_a_i&doctype=Standard -URIDate 2016-03-31 + Details
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- Definition The percentage of an expected dividend used to calculate the fair value of share options granted. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2016-01-13 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2016-03-30&anchor=para_47_a_i&doctype=Standard -URIDate 2016-03-31 + Details
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- Definition The weighted average fair value of share options granted during the period at the measurement date. [Refer: Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2016-01-13 -Paragraph 47 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2016-03-30&anchor=para_47_a&doctype=Standard -URIDate 2016-03-31 + Details
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