Share-based Payments Arrangement - Black-Scholes Model and Related Assumptions used to Evaluate Options and Fair Value of Options by CHTSC (Detail) - CHT Security Co., Ltd. (CHTSC) [Member]	Dec. 20, 2019 TWD ($) yr $ / shares
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Grant-date share price	$ 20.17
Exercise price	$ 19.085
Dividends yield	12.49%
Risk-free interest rate	0.54%
Expected life \| yr	5
Expected volatility	42.41%
Weighted average fair value of grants \| $	$ 2,470

Share price per share.

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
-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

+ 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

+ 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

+ Details

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- Definition

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

+ References

+ 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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