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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) | Oct. 31, 2018 TWD ($) yr $ / shares | May 22, 2018 TWD ($) d $ / shares | Dec. 19, 2017 TWD ($) yr $ / shares | Sep. 18, 2017 TWD ($) d $ / shares | Oct. 22, 2015 TWD ($) yr $ / shares
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CHIEF Telecom Inc. (CHIEF) [Member] |  |  |  |  |
Disclosure of terms and conditions of share-based payment arrangement [Line Items] |  |  |  |  |
Grant-date share price | $ 166.00 | $ 156.41 | $ 95.92 |  | $ 39.55
Exercise price | $ 147.00 | $ 170.00 | $ 147.00 |  | $ 43.00
Dividends yield | 0.00% | 0.00% | 0.00% |  | 0.00%
Risk-free interest rate | 0.72% | 0.34% | 0.62% |  | 0.86%
Expected life | 5 | 7 | 5 |  | 5
Expected volatility | 16.60% | 14.33% | 17.35% |  | 21.02%
Weighted average fair value of grants | $ | $ 33,540 | $ 0 | $ 2,318 |  | $ 4,863
Chunghwa Precision Test Tech. Co., Ltd. (CHPT) [Member] |  |  |  |  |
Disclosure of terms and conditions of share-based payment arrangement [Line Items] |  |  |  |  |
Grant-date share price |  |  |  | $ 1,295.00 |
Exercise price |  |  |  | $ 1,267.33 |
Dividends yield |  |  |  | 0.00% |
Risk-free interest rate |  |  |  | 0.35% |
Expected life | d |  |  |  | 4 |
Expected volatility |  |  |  | 28.30% |
Weighted average fair value of grants | $ |  |  |  | $ 31.60 |

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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 2019-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_47_a_i&doctype=Standard -URIDate 2019-03-27 + 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 2019-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_47_a_i&doctype=Standard -URIDate 2019-03-27 + 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 2019-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_47_a_i&doctype=Standard -URIDate 2019-03-27 + 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 2019-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_47_a_i&doctype=Standard -URIDate 2019-03-27 + 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 2019-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_47_a_i&doctype=Standard -URIDate 2019-03-27 + 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 2019-01-01 -Paragraph 47 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_47_a&doctype=Standard -URIDate 2019-03-27 + Details
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- Details
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